Document and Entity Information - USD ($) $ in Billions	12 Months Ended
Document and Entity Information - USD ($) $ in Billions	Dec. 31, 2018	Feb. 26, 2019	Jun. 29, 2018
Document Information [Abstract]
Entity Registrant Name	MERIT MEDICAL SYSTEMS INC
Entity Central Index Key	0000856982
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		54,902,835
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	No
Entity Public Float			$ 2.5

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Cash and cash equivalents	$ 67,359	$ 32,336
Trade receivables — net of allowance for uncollectible accounts — 2018 — $2,355 and 2017 — $1,769	137,174	105,536
Other receivables	11,879	9,429
Inventories	197,536	155,288
Prepaid expenses and other assets	11,326	9,096
Prepaid income taxes	3,627	3,225
Income tax refund receivables	933	1,211
Total current assets	429,834	316,121
PROPERTY AND EQUIPMENT:
Land and land improvements	26,801	19,877
Buildings	151,251	147,356
Manufacturing equipment	221,029	197,651
Furniture and fixtures	54,765	49,528
Leasehold improvements	33,678	31,161
Construction-in-progress	53,491	32,896
Total property and equipment	541,015	478,469
Less accumulated depreciation	(209,563)	(185,649)
Property and equipment — net	331,452	292,820
OTHER ASSETS:
Goodwill	335,433	238,147
Deferred income tax assets	3,001	2,359
Other assets	57,579	35,040
Total other assets	858,726	502,870
TOTAL	1,620,012	1,111,811
CURRENT LIABILITIES:
Trade payables	54,024	34,931
Accrued expenses	96,173	58,932
Current portion of long-term debt	22,000	19,459
Income taxes payable	3,146	2,298
Total current liabilities	175,343	115,620
LONG-TERM DEBT	373,152	259,013
DEFERRED INCOME TAX LIABILITIES	56,363	23,289
LONG-TERM INCOME TAXES PAYABLE	392	4,846
LIABILITIES RELATED TO UNRECOGNIZED TAX BENEFITS	3,013	2,746
DEFERRED COMPENSATION PAYABLE	11,219	11,181
DEFERRED CREDITS	2,261	2,403
OTHER LONG-TERM OBLIGATIONS	65,494	16,379
Total liabilities	687,237	435,477
COMMITMENTS AND CONTINGENCIES (Notes 3, 8, 9, and 10)
STOCKHOLDERS’ EQUITY:
Preferred stock — 5,000 shares authorized as of December 31, 2018 and 2017; no shares issued	0	0
Common stock, no par value; shares authorized — 2018 and 2017 - 100,000; issued and outstanding as of December 31, 2018 - 54,893 and December 31, 2017 - 50,248	571,383	353,392
Retained earnings	363,425	321,408
Accumulated other comprehensive income (loss)	(2,033)	1,534
Total stockholders’ equity	932,775	676,334
TOTAL	1,620,012	1,111,811
Developed technology — net of accumulated amortization — 2018 — $102,357 and 2017 — $72,420
OTHER ASSETS:
Intangible assets	383,147	167,771
Other — net of accumulated amortization — 2018 — $49,136 and 2017 — $38,127
OTHER ASSETS:
Intangible assets	$ 79,566	$ 59,553

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
CURRENT ASSETS:
Trade receivables, allowances	$ 2,355	$ 1,769
STOCKHOLDERS’ EQUITY:
Preferred stock shares authorized (in shares)	5,000,000	5,000,000
Preferred stock shares issued (in shares)	0	0
Common stock shares authorized (in shares)	100,000,000	100,000,000
Common stock shares issued (in shares)	54,893,000	50,248,000
Common stock shares outstanding (in shares)	54,893,000	50,248,000
Other
OTHER ASSETS:
Intangibles, accumulated amortization	$ 49,136	$ 38,127
Developed technology
OTHER ASSETS:
Intangibles, accumulated amortization	$ 102,357	$ 72,420

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
NET SALES	$ 882,753,000	$ 727,852,000	$ 603,838,000
COST OF SALES	487,983,000	401,599,000	338,813,000
GROSS PROFIT	394,770,000	326,253,000	265,025,000
OPERATING EXPENSES:
Selling, general and administrative	276,018,000	229,134,000	184,398,000
Research and development	59,532,000	51,403,000	45,229,000
Intangible asset impairment charges	657,000	809,000	0
Contingent consideration expense (benefit)	(698,000)	(298,000)	61,000
Acquired in-process research and development	644,000	12,136,000	461,000
Total operating expenses	336,153,000	293,184,000	230,149,000
INCOME FROM OPERATIONS	58,617,000	33,069,000	34,876,000
OTHER INCOME (EXPENSE):
Interest income	1,199,000	381,000	81,000
Interest expense	(10,360,000)	(7,736,000)	(8,798,000)
Gain on bargain purchase	0	11,039,000	0
Other income (expense) - net	63,000	(872,000)	(773,000)
Other income (expense) — net	(9,098,000)	2,812,000	(9,490,000)
INCOME BEFORE INCOME TAXES	49,519,000	35,881,000	25,386,000
INCOME TAX EXPENSE	7,502,000	8,358,000	5,265,000
NET INCOME	$ 42,017,000	$ 27,523,000	$ 20,121,000
EARNINGS PER COMMON SHARE:
Basic (in dollars per share)	$ 0.80	$ 0.56	$ 0.45
Diluted (in dollars per share)	$ 0.78	$ 0.55	$ 0.45
AVERAGE COMMON SHARES:
Basic (in shares)	52,268	48,805	44,408
Diluted (in shares)	53,931	50,101	44,862

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 42,017	$ 27,523	$ 20,121
Other comprehensive income (loss):
Cash flow hedges	64
Cash flow hedges		901	4,784
Less income tax (expense)	(16)
Less income tax (expense)		(350)	(1,861)
Foreign currency translation adjustment	(3,606)	3,117	878
Less income tax (expense)	(9)	(252)	(196)
Total other comprehensive income (loss)	(3,567)	3,416	3,605
Total comprehensive income	$ 38,450	$ 30,939	$ 23,726

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2015	$ 466,103	$ 197,826	$ 273,764	$ (5,487)
Beginning balance (in shares) at Dec. 31, 2015		44,267
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	20,121		20,121
Other comprehensive income (loss)	3,605			3,605
Excess tax benefits from stock-based compensation	669	$ 669
Stock-based compensation expense	2,506	2,506
Options exercised	4,923	$ 4,923
Options exercised (in shares)		362
Issuance of common stock under Employee Stock Purchase Plans	694	$ 694
Issuance of common stock under Employee Stock Purchase Plans (in shares)		34
Shares surrendered in exchange for payment of payroll tax liabilities	(86)	$ (86)
Shares surrendered in exchange for payment of payroll tax liabilities (in shares)		(4)
Shares surrendered in exchange for exercise of stock options	(346)	$ (346)
Shares surrendered in exchange for the exercise of stock options (in shares)		(14)
Ending balance at Dec. 31, 2016	498,189	$ 206,186	293,885	(1,882)
Ending balance (in shares) at Dec. 31, 2016		44,645
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,523		27,523
Other comprehensive income (loss)	3,416			3,416
Stock-based compensation expense	4,075	$ 4,075
Options exercised	5,689	$ 5,689
Options exercised (in shares)		404
Issuance of common stock under Employee Stock Purchase Plans	836	$ 836
Issuance of common stock under Employee Stock Purchase Plans (in shares)		24
Issuance of common stock, net of offering costs	136,606	$ 136,606
Issuance of common stock, net of offering costs (in shares)		5,175
Shares surrendered in exchange for exercise of stock options	0
Shares surrendered in exchange for the exercise of stock options (in shares)		0
Ending balance at Dec. 31, 2017	$ 676,334	$ 353,392	321,408	1,534
Ending balance (in shares) at Dec. 31, 2017	50,248	50,248
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 42,017		42,017
Other comprehensive income (loss)	(3,567)			(3,567)
Stock-based compensation expense	6,117	$ 6,117
Options exercised	$ 10,634	$ 10,634
Options exercised (in shares)	690	690
Issuance of common stock under Employee Stock Purchase Plans	$ 1,087	$ 1,087
Issuance of common stock under Employee Stock Purchase Plans (in shares)		22
Issuance of common stock, net of offering costs	205,030	$ 205,030
Issuance of common stock, net of offering costs (in shares)		4,025
Shares surrendered in exchange for payment of payroll tax liabilities	(2,616)	$ (2,616)
Shares surrendered in exchange for payment of payroll tax liabilities (in shares)		(49)
Shares surrendered in exchange for exercise of stock options	(2,261)	$ (2,261)
Shares surrendered in exchange for the exercise of stock options (in shares)		(43)
Ending balance at Dec. 31, 2018	$ 932,775	$ 571,383	$ 363,425	$ (2,033)
Ending balance (in shares) at Dec. 31, 2018	54,893	54,893

CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	12 Months Ended
CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 42,017	$ 27,523	$ 20,121
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	69,546	53,582	43,755
Gain on bargain purchase	0	(11,039)	0
Losses on sales and/or abandonment of property and equipment	625	427	530
Write-off of patents and intangible assets	814	988	101
Acquired in-process research and development	644	12,136	461
Amortization of deferred credits	(142)	(147)	(170)
Amortization of long-term debt issuance costs	804	685	952
Deferred income taxes	2,052	(1,304)	(962)
Excess tax benefits from stock-based compensation	0	0	(669)
Stock-based compensation expense	6,117	4,075	2,506
Changes in operating assets and liabilities, net of effects from acquisitions:
Trade receivables	(27,522)	(12,844)	(6,816)
Other receivables	(2,754)	(3,557)	1,161
Inventories	(28,172)	(17,834)	(3,656)
Prepaid expenses and other current assets	(2,000)	(1,236)	271
Prepaid income taxes	(444)	(611)	404
Income tax refund receivables	232	(588)	406
Other assets	315	(3,735)	(3,763)
Trade payables	15,726	417	(6,835)
Accrued expenses	12,706	6,461	3,242
Income taxes payable	918	21	1,451
Long-term income taxes payable	(4,454)	4,846	0
Liabilities related to unrecognized tax benefits	267	(19)	597
Deferred compensation payable	39	1,970	712
Other long-term obligations	(801)	2,510	(200)
Total adjustments	44,516	35,204	33,478
Net cash provided by operating activities	86,533	62,727	53,599
Capital expenditures for:
Property and equipment	(63,324)	(38,623)	(32,837)
Intangible assets	(3,012)	(2,577)	(2,217)
Proceeds from sale of cost method investment	0	0	1,089
Proceeds from the sale of property and equipment	55	21	19
Issuance of notes receivable	(10,750)	0	0
Cash paid in acquisitions, net of cash acquired	(301,789)	(105,582)	(125,161)
Net cash used in investing activities	(378,820)	(146,761)	(159,107)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock	214,993	143,810	5,271
Offering costs	(366)	(816)	0
Proceeds from issuance of long-term debt	639,108	197,214	219,505
Payments on long-term debt	(522,608)	(243,214)	(102,098)
Excess tax benefits from stock-based compensation	0	0	669
Long-term debt issuance costs	0	(416)	(1,948)
Contingent payments related to acquisitions	(231)	(61)	(218)
Payment of taxes related to an exchange of common stock	(2,616)	0	(86)
Net cash provided by financing activities	328,280	96,517	121,095
EFFECT OF EXCHANGE RATES ON CASH	(970)	682	(593)
NET INCREASE IN CASH AND CASH EQUIVALENTS	35,023	13,165	14,994
CASH AND CASH EQUIVALENTS:
Beginning of year	32,336	19,171	4,177
End of year	67,359	32,336	19,171
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest (net of capitalized interest of $647, $513 and $460, respectively)	10,324	7,707	8,872
Income taxes	8,692	6,049	2,318
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Property and equipment purchases in accounts payable	4,989	1,992	2,398
Contingent receivable in exchange for sale of equity investment	0	0	711
Receivable for issuance of common stock associated with option exercises	0	137	0
Acquisition purchases in accrued expenses and other long-term obligations	72,209	10,488	0
Merit common stock surrendered (43, 0 and 14 shares, respectively) in exchange for exercise of stock options	$ 2,261	$ 0	$ 346

Organization and Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization and Summary of Significant Accounting Policies

ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Organization. Merit Medical Systems, Inc. (“Merit,” “we,” or “us”) designs, develops, manufactures and markets single-use medical products for interventional and diagnostic procedures. For financial reporting purposes, we report our operations in two operating segments: cardiovascular and endoscopy. Our cardiovascular segment consists of cardiology and radiology medical device products which assist in diagnosing and treating coronary artery disease, peripheral vascular disease and other non-vascular diseases and includes embolotherapeutic, cardiac rhythm management, electrophysiology, critical care, and interventional oncology and spine devices. Our endoscopy segment consists of gastroenterology and pulmonology devices which assist in the palliative treatment of expanding esophageal, tracheobronchial and biliary strictures caused by malignant tumors. Within those two operating segments, we offer products focused in six core product groups: peripheral intervention, cardiac intervention, interventional oncology and spine, cardiovascular and critical care, breast cancer localization and guidance, and endoscopy.

We manufacture our products in plants located in the U.S., Mexico, The Netherlands, Ireland, France, Brazil, Australia, and Singapore. We export sales to dealers and have direct or modified direct sales forces in the U.S., Canada, Western Europe, Australia, Brazil, Russia, Japan, China, Malaysia, South Korea, UAE, India, New Zealand and South Africa (see Note 13). Our consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States. The following is a summary of the more significant of such policies.

Use of Estimates in Preparing Financial Statements. The preparation of financial statements in conformity with accounting principles generally accepted in the United States ("U.S. GAAP") requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Principles of Consolidation. The consolidated financial statements include our wholly owned subsidiaries. Intercompany balances and transactions have been eliminated.

Cash and Cash Equivalents. For purposes of the statements of cash flows, we consider interest bearing deposits with an original maturity date of three months or less to be cash equivalents.

Receivables. Trade accounts receivable are recorded at the net invoice value and are not interest bearing. An allowance for uncollectible accounts receivable is recorded based on our historical bad debt experience and on management’s evaluation of our ability to collect individual outstanding balances. Once collection efforts have been exhausted and a receivable is deemed to be uncollectible, such balance is charged against the allowance for uncollectible accounts.

Inventories. We value our inventories at the lower of cost, at approximate costs determined on a first-in, first-out method, or net realizable value. Net realizable value is the estimated selling price in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. Inventory costs include material, labor and manufacturing overhead. We review inventories on hand at least quarterly and record provisions for estimated excess, slow moving and obsolete inventory, as well as inventory with a carrying value in excess of net realizable value. The regular and systematic inventory valuation reviews include a current assessment of future product demand, historical experience and product expiration.

Goodwill and Intangible Assets. We test goodwill balances for impairment on an annual basis as of July 1 or whenever impairment indicators arise. We utilize several reporting units in evaluating goodwill for impairment. We assess the estimated fair value of reporting units using a combination of a guideline public company market-based approach and a discounted cash flow income-based approach. If the carrying amount of a reporting unit exceeds the fair value of the reporting unit, an impairment charge is recognized in an amount equal to the excess of the carrying amount of the reporting unit goodwill over the implied fair value of that goodwill.

Finite-lived intangible assets including developed technology, customer lists, distribution agreements, license agreements, trademarks, covenants not to compete and patents are subject to amortization. Intangible assets are amortized over their estimated useful life on a straight-line basis, except for customer lists, which are generally amortized on an accelerated basis. Estimated useful lives are determined considering the period the assets are expected to contribute to future cash flows. We evaluate the recoverability of our finite-lived intangible assets periodically and take into account events or circumstances that warrant revised estimates of useful lives or that indicate impairment exists.

In-process technology intangible assets, which are not subject to amortization until projects reach commercialization, are assessed for impairment at least annually and more frequently if events occur that would indicate a potential reduction in the fair value of the assets below their carrying value. An impairment charge would be recognized to the extent the carrying amount of the in-process technology exceeded its fair value.

Long-Lived Assets. We periodically review the carrying amount of our depreciable long-lived assets for impairment. An asset is considered impaired when estimated future cash flows are less than the carrying amount of the asset. In the event the carrying amount of such asset is not considered recoverable, the asset is adjusted to its fair value. Fair value is generally determined based on discounted future cash flow.

Property and Equipment. Property and equipment is stated at the historical cost of construction or purchase. Construction costs include interest costs capitalized during construction. Maintenance and repairs of property and equipment are charged to operations as incurred. Leasehold improvements are amortized over the lesser of the base term of the lease or estimated life of the leasehold improvements. Construction-in-process consists of new buildings and various production equipment being constructed internally and externally. Assets in construction-in-process will commence depreciating once the asset has been placed in service. Depreciation is computed using the straight-line method over estimated useful lives as follows:



Buildings	40 years
Manufacturing equipment	4	-	20 years
Furniture and fixtures	3	-	20 years
Land improvements	10	-	20 years
Leasehold improvements	4	-	25 years

Depreciation expense related to property and equipment for the years ended December 31, 2018, 2017 and 2016 was approximately $28.3 million, $26.8 million, and $24.5 million, respectively.

Deferred Compensation. We have a deferred compensation plan that permits certain management employees to defer a portion of their salary until the future. We established a Rabbi trust to finance obligations under the plan with corporate-owned variable life insurance contracts. The cash surrender value totaled approximately $11.7 million and $11.7 million at December 31, 2018 and 2017, respectively, which is included in other assets in our consolidated balance sheets. We have recorded a deferred compensation payable of approximately $11.2 million and $11.2 million at December 31, 2018 and 2017, respectively, to reflect the liability to our employees under this plan.

Other Assets. Other assets consist of our deferred compensation plan cash surrender value discussed above, unamortized issuance costs on revolving debt, investments in privately-held companies, notes receivable issued to third-parties, a long-term income tax refund receivable, deposits related to various leases, and the long-term assets related to derivatives.

We analyze our investments to determine if they should be accounted for using the equity method based on our ability to exercise significant influence over operating and financial policies of the investment. Our share of earnings associated with equity method investments is reported within other income (expense) in our consolidated statements of income. Investments not accounted for under the equity method of accounting are accounted for under the cost method of accounting wherein impairment charges are recognized if circumstances suggest that the value of the investment has changed.

Deferred Credits. Deferred credits consist of grant money received from the Irish government. Grant money is received for a percentage of expenditures on eligible property and equipment, specific research and development projects and costs of hiring and training employees. Amounts related to the acquisition of property and equipment are amortized as a reduction of depreciation expense over the lives of the corresponding property and equipment.

Revenue Recognition. We sell our medical products through a direct sales force in the U.S. and through OEM relationships, custom procedure tray manufacturers and a combination of direct sales force and independent distributors in international markets. Revenue is recognized when a customer obtains control of promised goods based on the consideration we expect to receive in exchange for these goods. This core principle is achieved through the following steps:

Identify the contract with the customer. A contract with a customer exists when (i) we enter into an enforceable contract with a customer that defines each party’s rights regarding the goods to be transferred and identifies the payment terms related to these goods, (ii) the contract has commercial substance and, (iii) we determine that collection of substantially all consideration for services that are transferred is probable based on the customer’s intent and ability to pay the promised consideration. We do not

have significant costs to obtain contracts with customers. For commissions on product sales, we have elected the practical expedient to expense the costs as incurred if the amortization period would have been one year or less.

Identify the performance obligations in the contract. Generally, our contracts with customers do not include multiple performance obligations to be completed over a period of time. Our performance obligations generally relate to delivering single-use medical products to a customer, subject to the shipping terms of the contract. Limited warranties are provided, under which we typically accept returns and provide either replacement parts or refunds. We do not have significant returns. We do not typically offer extended warranty or service plans.

Determine the transaction price. Payment by the customer is due under customary fixed payment terms, and we evaluate if collectability is reasonably assured. None of our contracts as of December 31, 2018 contained a significant financing component. Revenue is recorded at the net sales price, which includes estimates of variable consideration such as product returns, rebates, discounts, and other adjustments. The estimates of variable consideration are based on historical payment experience, historical and projected sales data, and current contract terms. Variable consideration is included in revenue only to the extent that it is probable that a significant reversal of the revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. Taxes collected from customers relating to product sales and remitted to governmental authorities are excluded from revenues.

Allocate the transaction price to performance obligations in the contract. We typically do not have multiple performance obligations in our contracts with customers. As such, we generally recognize revenue upon transfer of the product to the customer's control at contractually stated pricing.

Recognize revenue when or as we satisfy a performance obligation. We generally satisfy performance obligations at a point in time upon either shipment or delivery of goods, in accordance with the terms of each contract with the customer. We do not have significant service revenue.

Reserves are recorded as a reduction in net sales and are not considered material to our consolidated statements of income for the years ended December 31, 2018, 2017 and 2016. In addition, we invoice our customers for taxes assessed by governmental authorities such as sales tax and value added taxes. We present these taxes on a net basis.

Shipping and Handling. We bill our customers for shipping and handling charges, which are included in net sales for the applicable period, and the corresponding shipping and handling expense is reported in cost of sales.

Cost of Sales. We include product costs (i.e. material, direct labor and overhead costs), shipping and handling expense, product royalty expense, developed technology amortization expense, production-related depreciation expense and product license agreement expense in cost of sales.

Research and Development. Research and development costs are expensed as incurred.

Income Taxes. Under our accounting policies, we initially recognize a tax position in our financial statements when it becomes more likely than not that the position will be sustained upon examination by the tax authorities. Such tax positions are initially and subsequently measured as the largest amount of tax positions that has a greater than 50% likelihood of being realized upon ultimate settlement with the tax authorities assuming full knowledge of the position and all relevant facts. Although we believe our provisions for unrecognized tax positions are reasonable, we can make no assurance that the final tax outcome of these matters will not be different from that which we have reflected in our income tax provisions and accruals. The tax law is subject to varied interpretations, and we have taken positions related to certain matters where the law is subject to interpretation. Such differences could have a material impact on our income tax provisions and operating results in the period(s) in which we make such determination.

Earnings per Common Share. Net income per common share is computed by both the basic method, which uses the weighted average number of our common shares outstanding, and the diluted method, which includes the dilutive common shares from stock options and warrants, as calculated using the treasury stock method.

Fair Value Measurements. The fair value of a financial instrument is the amount that could be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Financial assets are marked to bid prices and financial liabilities are marked to offer prices. Fair value measurements do not include transaction costs. A fair value hierarchy is used to prioritize the quality and reliability of the information used to determine fair values. Categorization within the fair value hierarchy is based on the lowest level of input that is significant to the fair value measurement. The fair value hierarchy is defined in the following three categories:

Level 1: Quoted market prices in active markets for identical assets or liabilities.

Level 2: Observable market-based inputs or inputs that are corroborated by market data.

Level 3: Unobservable inputs that are not corroborated by market data.

Stock-Based Compensation. We recognize the fair value compensation cost relating to stock-based payment transactions in accordance with ASC 718, Compensation — Stock Compensation. Under the provisions of ASC 718, stock-based compensation cost is measured at the grant date, based on the fair value of the award, and is recognized over the employee’s requisite service period, which is generally the vesting period. The fair value of our stock options is estimated using a Black-Scholes option valuation model. Stock-based compensation expense for the years ended December 31, 2018, 2017 and 2016 was approximately $6.1 million, $4.1 million and $2.5 million, respectively.

Concentration of Credit Risk. Financial instruments that potentially subject us to concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. We provide credit, in the normal course of business, primarily to hospitals and independent third-party custom procedure tray manufacturers and distributors. We perform ongoing credit evaluations of our customers and maintain allowances for potential credit losses. Sales to our single largest customer accounted for approximately 2%, 2%, and 3% of net sales for the years ended December 31, 2018, 2017 and 2016, respectively.

Foreign Currency. The financial statements of our foreign subsidiaries are measured using local currencies as the functional currency, with the exception of our subsidiaries in Ireland and Mexico, which each use the U.S. Dollar as its functional currency. Assets and liabilities are translated into U.S. Dollars at year-end rates of exchange and results of operations are translated at average rates for the year. Gains and losses resulting from these translations are included in accumulated other comprehensive income (loss) as a separate component of stockholders’ equity. Foreign currency transactions denominated in a currency other than the entity’s functional currency are included in determining net income for the period.

Accumulated Other Comprehensive Income (Loss). As of December 31, 2018, accumulated other comprehensive loss included approximately $3.5 million (net of tax of $(2.2) million) related to cash flow hedges and $(5.6) million (net of tax of $(9,000)) related to foreign currency translation. As of December 31, 2017, accumulated other comprehensive income included approximately $3.5 million (net of tax of $(2.2) million) related to cash flow hedges and $(1.9) million (net of tax of $0) related to foreign currency translation.

New Financial Accounting Standards.

Recently Adopted

In October 2016, the FASB issued Accounting Standards Update ("ASU") No. 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other than Inventory, which requires the recognition of the income tax consequences of an intra-entity transfer of an asset, other than inventory, when the transfer occurs. ASU 2016-16 became effective for us as of January 1, 2018. The adoption of ASU 2016-16 did not have a material impact on our consolidated financial statements for the year ended December 31, 2018.

In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230): Classification of Certain Cash Receipts and Cash Payments, which addresses eight specific cash flow issues with the objective of reducing the existing diversity in practice in how certain cash receipts and cash payments are presented and classified in the statement of cash flows. ASU 2016-15 became effective for us on January 1, 2018. The adoption of ASU 2016-15 did not have a material impact on our consolidated financial statements for the year ended December 31, 2018.

In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall: Recognition and Measurement of Financial Assets and Financial Liabilities, which amends the guidance regarding the classification and measurement of financial instruments. Changes to the current guidance primarily affect the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. In addition, ASU 2016-01 clarifies guidance related to the valuation allowance assessment when recognizing deferred tax assets resulting from unrealized losses on

available-for-sale debt securities. We adopted ASU 2016-01 on January 1, 2018. The adoption of ASU 2016-01 did not have a material impact on our consolidated financial statements for the year ended December 31, 2018.

The FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which provides a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers. We adopted this ASU (and all subsequent ASUs that modified Topic 606) effective January 1, 2018 on a modified retrospective basis. Adoption of this standard did not result in significant changes to our accounting policies, business processes, systems or controls, or have a material impact on our financial position, results of operations or cash flows. As such, prior period amounts are not adjusted and continue to be reported under accounting standards then in effect, and we did not record a cumulative adjustment to the opening equity balance of retained earnings as of January 1, 2018. However, additional disclosures have been added in accordance with the requirements of Topic 606 and are reflected in Note 2.

Not Yet Adopted

In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), ("ASC 842"). The objective of the guidance in ASC 842 is to increase transparency and comparability among organizations by recognizing lease assets and liabilities in the balance sheet and disclosing key information. ASC 842 amends previous lease guidance to require a lessee to recognize a lease liability and a right-of-use asset on the entity’s balance sheet for all leases with terms that exceed one year. ASC 842 is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. ASC 842 provides that lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented.

We have completed our assessment of all our leases, and we estimate that the impact of the adoption of ASC 842 will result in recognition of operating right-of-use assets and lease liabilities of approximately $80 million. We do not expect the adoption to have a material impact on our statements of operations or cash flows. ASC 842 allows for several practical expedients which permit the following: no reassessment of lease classification or initial direct costs; use of the standard’s effective date as the date of initial application; and no separation of non-lease components from the related lease components and, instead, to account for those components as a single lease component if certain criteria are met. We expect to elect these practical expedients and adopt ASC 842 on January 1, 2019 using the effective date as our date of initial application. Therefore, financial information and disclosures under ASC 842 will not be provided for periods prior to January 1, 2019.

In February 2018, the FASB issued ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income, which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act enacted in December 2017. ASU 2018-02 is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. We do not believe that the adoption of ASU 2018-02 will have a material impact on our consolidated financial statements.

In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities, which expands and refines hedge accounting for both financial and non-financial risk components, aligns the recognition and presentation of the effects of hedging instruments and hedge items in the financial statements, and includes certain targeted improvements to ease the application of current guidance related to the assessment of hedge effectiveness. ASU 2017-12 is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. We do not anticipate the impact of adopting ASU 2017-12 will be material to our consolidated financial statements.

All other issued and not yet effective accounting standards are not relevant to our financial statements.

Revenues

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Revenues

REVENUES

The following table presents sales by operating segment disaggregated based on type of product and geographic region for the years ended December 31, 2018, 2017 and 2016.



	Year Ended December 31, 2018						Year Ended December 31, 2017						Year Ended December 31, 2016
	United States		International		Total		United States		International		Total		United States		International		Total
Cardiovascular
Stand-alone devices	$	202,129	$	159,484	$	361,613	$	148,620	$	126,836	$	275,456	$	105,250	$	85,877	$	191,127
Cianna Medical	6,292		—		6,292		—		—		—		—		—		—
Custom kits and procedure trays	92,975		41,781		134,756		92,474		33,615		126,089		93,109		26,138		119,247
Inflation devices	31,717		60,702		92,419		31,848		48,027		79,875		35,506		38,410		73,916
Catheters	68,708		86,817		155,525		62,284		65,463		127,747		56,899		56,468		113,367
Embolization devices	20,433		29,605		50,038		22,374		27,158		49,532		24,075		21,960		46,035
CRM/EP	41,970		6,864		48,834		36,746		5,168		41,914		32,561		3,898		36,459
Total	464,224		385,253		849,477		394,346		306,267		700,613		347,400		232,751		580,151

Endoscopy
Endoscopy devices	32,189		1,087		33,276		26,357		882		27,239		22,950		737		23,687

Total	$	496,413	$	386,340	$	882,753	$	420,703	$	307,149	$	727,852	$	370,350	$	233,488	$	603,838

Note: Certain revenue categories for 2017 and 2016 have been adjusted from prior disclosures to reflect changes in product classifications to be consistent with updates in management of our product portfolios during 2018. Also note that Cianna Medical is a new category in 2018 as a result of the acquisition in November 2018 (see Note 3).

Acquisitions

12 Months Ended

Dec. 31, 2018

Business Combinations [Abstract]

Acquisitions

ACQUISITIONS

On December 14, 2018, we consummated an acquisition transaction contemplated by an asset purchase agreement with Vascular Insights, LLC and VI Management, Inc. (combined "Vascular Insights") and acquired Vascular Insight's intellectual property rights, inventory and certain other assets, including, the ClariVein® IC system and the ClariVein OC system. The ClariVein systems are specialty infusion and occlusion catheter systems with rotating wire tips designed for the controlled 360-degree dispersion of physician-specified agents to the targeted treatment area. We accounted for this acquisition as a business combination. The purchase consideration included an upfront payment of $40 million, and we are obligated to pay up to an additional $20 million based on achieving certain revenue milestones specified in the asset purchase agreement. The sales and results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date and were not material. Acquisition-related costs associated with the Vascular Insights acquisition, which were included in selling, general and administrative expenses in our consolidated statements of income, were not material. Given the circumstances of this acquisition, which closed in December 2018, as well as the complexity of the transaction, the purchase price allocation disclosed herein is considered provisional at this time and subject to adjustment. We are in the process of finalizing the net working capital adjustment pursuant to the asset purchase agreement and the valuation of the acquired intangible assets and contingent consideration. The purchase price was preliminarily allocated as follows (in thousands):



Inventories	$	1,308
Intangibles
Developed technology	32,830
Customer list	840
Trademarks	1,410
Goodwill	21,832

Total assets acquired	$	58,220

We are amortizing the developed technology intangible assets over 12 years, the related trademarks over nine years and the customer list on an accelerated basis over eight years. The total weighted-average amortization period for these acquired intangible assets is approximately 11.8 years.

On November 13, 2018 we consummated an acquisition transaction contemplated by a merger agreement to acquire Cianna Medical, Inc. ("Cianna Medical"). The purchase consideration consisted of an upfront payment of $135 million plus an

initial working capital adjustment of $1 million in cash, with potential earn-out payments of an additional $15 million for achievement of supply chain and scalability metrics, and up to an additional $50 million for achievement of sales milestones. Cianna Medical developed the first non-radioactive, wire-free breast cancer localization system. Its SCOUT® and SAVI® Brachy technologies are FDA-cleared and address unmet needs in the delivery of radiation therapy, tumor localization and surgical guidance. We accounted for this acquisition as a business combination. During the year ended December 31, 2018, our net sales of Cianna Medical products were approximately $6.3 million. It is not practical to separately report earnings related to the products acquired from Cianna Medical, as we cannot split out sales costs related solely to the products we acquired from Cianna Medical, principally because our sales representatives sell multiple products (including the products we acquired from Cianna Medical) in our cardiovascular business segment. Acquisition-related costs associated with the Cianna Medical acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were approximately $3.5 million for the year ended December 31, 2018. The following table summarizes the preliminary purchase price allocated to the net assets acquired from Cianna Medical (in thousands):



Assets Acquired
Trade receivables	$	6,151
Inventories	5,803
Prepaid expenses and other assets	315
Property and equipment	1,047
Other long-term assets	14
Intangibles
Developed technology	134,510
Customer lists	3,330
Trademarks	7,080
Goodwill	65,885
Total assets acquired	224,135

Liabilities Assumed
Trade payables	(1,497		)
Accrued expenses	(2,384		)
Other long-term liabilities	(1,527		)
Deferred tax liabilities	(30,363		)
Total liabilities assumed	(35,771		)

Total net assets acquired	$	188,364

We are amortizing the developed technology intangible assets over 11 years, the related trademarks over ten years and the customer lists on an accelerated basis over eight years. The total weighted-average amortization period for these acquired intangible assets is approximately 10.7 years.

During July 2018, we purchased 1,786,000 preferred limited liability company units of Cagent Vascular, LLC, a medical device company ("Cagent"), for approximately $2.2 million. We had previously purchased 3,000,000 preferred limited liability company units for approximately $3.0 million during 2016 and 2017. Our investment has been recorded as an equity investment accounted for at cost and reflected within other assets in the accompanying consolidated balance sheets because we are not able to exercise significant influence over the operations of Cagent. Our total current investment in Cagent represents an ownership of approximately 19.5% of the outstanding stock.

On May 23, 2018, we entered into an asset purchase agreement with DirectACCESS Medical, LLC (“DirectACCESS”) to acquire its assets, including, certain product distribution agreements for the FirstChoice™ Ultra High Pressure PTA Balloon Catheter. We accounted for this acquisition as a business combination. The purchase price for the assets was approximately $7.3 million. The sales and results of operations related to the acquisition have been included in our cardiovascular segment since the acquisition date and were not material. Acquisition-related costs associated with the DirectACCESS acquisition, which were included in selling, general and administrative expenses in our consolidated statements of income, were not material. The purchase price was preliminarily allocated as follows (in thousands):



Inventories	$	971
Intangibles
Developed technology	4,840
Customer list	120
Trademarks	400
Goodwill	938

Total assets acquired	$	7,269

We are amortizing the developed technology intangible asset over ten years, the related trademarks over ten years and the customer list on an accelerated basis over five years. The total weighted-average amortization period for these acquired intangible assets is approximately 9.9 years.

On May 18, 2018, we paid $750,000 for a distribution agreement with QXMédical, LLC ("QXMédical") for the Q50® PLUS Stent Graft Balloon Catheter. We accounted for this acquisition as an asset purchase. We are amortizing the distribution

agreement intangible asset over a period of ten years.

On April 6, 2018, we entered into long-term agreements with NinePoint Medical, Inc. (“NinePoint”), pursuant to which we (a) became the exclusive worldwide distributor for the NvisionVLE® Imaging System with Real-time Targeting™ using Optical Coherence Tomography (OCT) and (b) acquired an option to purchase up to 100% of the outstanding equity in NinePoint throughout a three-month period commencing 18 months subsequent to the agreement date, both in exchange for total consideration of $10 million. We accounted for this transaction as an asset purchase. In addition, we made a loan to NinePoint for $10.5 million with a maturity date of April 6, 2023, at which time the loan, together with accrued interest thereon, will be due and payable. The loan bears interest at a rate of 9.0% and is collateralized by NinePoint's rights, interest and title to the NvisionVLE® Imaging System and any other product owned or licensed by NinePoint utilizing OCT. This loan has been recorded as a note receivable within other long-term assets in our consolidated balance sheets.

We utilized the consolidation of variable interest entities guidance to determine whether or not NinePoint was a variable interest entity ("VIE"), and if so, whether we are the primary beneficiary of NinePoint. As of December 31, 2018, we concluded that NinePoint is a VIE based on the fact that the equity investment at risk in NinePoint is not sufficient to finance its activities. We have also determined that Merit is not the primary beneficiary of NinePoint as we do not have the power to direct NinePoint's most significant activities. Our exposure to loss related to our transaction with NinePoint is the carrying value of the amounts paid to and due from NinePoint. The results of operations related to the NinePoint distribution agreement have been included in our endoscopy segment since the acquisition date. During the year ended December 31, 2018, our net sales of NinePoint products were approximately $3.0 million. We believe the NinePoint products will enhance the product offerings of our Endotek operating segment and will be another step in our strategy to add therapy and disease-state products to our portfolio.

On February 14, 2018, we acquired certain divested assets from Becton, Dickinson and Company ("BD"), for an aggregate purchase price of $100.3 million. We also recorded a contingent consideration liability of $1.6 million related to milestone payments payable pursuant to the terms of the acquired contract with Sontina Medical LLC. The assets acquired include the soft tissue core needle biopsy products sold under the tradenames of Achieve® Programmable Automatic Biopsy System, Temno® Biopsy System, Tru-Cut® Biopsy Needles as well as Aspira® Pleural Effusion Drainage Kits, and the Aspira® Peritoneal Drainage System. We accounted for this acquisition as a business combination.

During the year ended December 31, 2018, our net sales of BD products were approximately $42.1 million. It is not practical to separately report earnings related to the products acquired from BD, as we cannot split out sales costs related solely to the products we acquired from BD, principally because our sales representatives sell multiple products (including the products we acquired from BD) in our cardiovascular business segment. Acquisition-related costs associated with the BD acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were approximately $1.8 million for the year ended December 31, 2018. During the measurement period, which ended in December 2018, adjustments were made to finalize the allocation of purchase price related to intangible assets, goodwill and contingent liabilities. The following table summarizes the purchase price allocated to the assets acquired from BD (in thousands):



Inventories	$	5,804
Property and equipment	748
Intangibles
Developed technology	74,000
Customer list	4,200
Trademarks	4,900
In-process technology	2,500
Goodwill	9,728

Total assets acquired	$	101,880

We are amortizing the developed technology intangible assets over eight years, the related trademarks over nine years, and the customer lists on an accelerated basis over seven years. The total weighted-average amortization period for these acquired intangible assets is approximately 8 years.

On October 2, 2017 we acquired a custom procedure pack business located in Melbourne, Australia from ITL Healthcare Pty Ltd. ("ITL"), for an aggregate purchase price of $11.3 million. We accounted for this acquisition as a business combination. The following table summarizes the aggregate purchase price allocated to the assets acquired from ITL (in thousands):



Assets Acquired
Trade receivables	$	1,287
Other receivables	56
Inventories	1,808
Prepaid expenses and other assets	65
Property and equipment	1,053
Intangibles
Customer lists	5,940
Goodwill	3,945
Total assets acquired	14,154

Liabilities Assumed
Trade payables	(216		)
Accrued expenses	(747		)
Deferred tax liabilities	(1,901		)
Total liabilities assumed	(2,864		)

Total net assets acquired	$	11,290

We are amortizing the customer list on an accelerated basis over seven years. Acquisition-related costs associated with the ITL acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were not material. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018 and 2017, our net sales of ITL products were approximately $8.0 million and $3.3 million, respectively. It is not practical to separately report the earnings related to the ITL acquisition, as we cannot split out sales costs related solely to the products we acquired from ITL, principally because our sales representatives sell multiple products (including the products we acquired from ITL) in our cardiovascular business segment.

On September 1, 2017, we acquired intellectual property rights associated with a steerable guidewire system from IntelliMedical Technologies Pty. Ltd. ("IntelliMedical"). We made an initial payment of approximately $11.9 million in September 2017, and we are obligated to pay up to an additional A$15.0 million (Australian dollars) if certain milestones set forth in the share purchase agreement with IntelliMedical are achieved. We are also required to pay royalties equal to 6% of net sales, commencing upon the first commercial sale of the product and throughout the term of the applicable patents. We accounted for this transaction as an asset purchase. The initial payment has been included in the accompanying consolidated statements of income as acquired

in-process research and development expense for the year ended December 31, 2017, because both technological feasibility of the underlying research and development project had not yet been reached and such technology had no identified future alternative use as of the date of acquisition.

On August 4, 2017 we acquired from Laurane Medical S.A.S. ("Laurane") and its shareholders inventories and the intellectual property rights associated with certain manual bone biopsy devices, manual bone marrow needles and muscle biopsy kits for an aggregate purchase price of $16.5 million. We also recorded a contingent consideration liability of $5.5 million related to royalties potentially payable to Laurane's shareholders pursuant to the terms of an intellectual property purchase agreement. We accounted for this acquisition as a business combination. The following table summarizes the aggregate purchase price (including contingent royalty payment liabilities) allocated to the assets acquired from Laurane (in thousands):



Inventories	$	594
Intangibles
Developed technology	14,920
Customer list	120
Goodwill	6,366

Total net assets acquired	$	22,000

We are amortizing the developed technology intangible asset over 12 years and the customer list on an accelerated basis over one year. The total weighted-average amortization period for these acquired intangible assets is 11.9 years. The sales and results of operations related to the acquisition have been included in our cardiovascular segment since the acquisition date and were not material. Acquisition-related costs associated with the Laurane acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were not material.

On July 3, 2017, we acquired from Osseon LLC (“Osseon”) substantially all the assets related to Osseon’s vertebral augmentation products. We accounted for this acquisition as a business combination. The purchase price for the assets was approximately $6.8 million. Acquisition-related costs associated with the Osseon acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were not material. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018 and 2017, our net sales of Osseon products were approximately $2.1 million and $942,000, respectively. It is not practical to separately report the earnings related to the Osseon acquisition, as we cannot split out sales costs related solely to the products we acquired from Osseon, principally because our sales representatives sell multiple products (including the products we acquired from Osseon) in our cardiovascular business segment. The following table summarizes the purchase price allocated to the assets acquired (in thousands):



Inventories	$	979
Property and equipment	58
Intangibles
Developed technology	5,400
Customer list	200
Goodwill	203

Total net assets acquired	$	6,840

We are amortizing the developed technology intangible asset over nine years and customer lists on an accelerated basis over eight years. The total weighted-average amortization period for these acquired intangible assets is approximately 9.0 years.

On July 1, 2017, we entered into an exclusive license agreement with Pleuratech ApS ("Pleuratech") to acquire the rights to manufacture and sell the KatGuide^TM chest tube insertion tool. As of December 31, 2018, we had paid $2.0 million in connection with this agreement. We are obligated to pay an additional $5.0 million if certain milestones set forth in the license agreement are met. We are also required to pay royalties equal to 6% of net sales throughout the term of the license agreement. We accounted for this transaction as an asset purchase. We recorded the amount paid upon closing as a license agreement intangible asset, which we are amortizing over 15 years.

On June 16, 2017, we acquired from Lazarus Medical Technologies, LLC the patent rights and other intellectual property related to the Repositionable Chest Tube^TM and related devices. As of December 31, 2018, we had paid $620,000 in connection

with this agreement. We are also obligated to pay an additional $700,000 if certain milestones set forth in the purchase agreement are met. We are also required to pay royalties equal to 6% of net sales throughout the term of the purchase agreement. We accounted for this transaction as an asset purchase. We recorded the amount paid upon closing as a license agreement intangible asset, which we are amortizing over 15 years.

On May 23, 2017, we paid $2.5 million to acquire 182,000 shares of preferred stock of Fusion Medical, Inc. ("Fusion"), a developer of medical devices designed primarily for clot removal. The shares of preferred stock we acquired, which represent an ownership interest of approximately 19.5%, have been accounted for as an equity method investment of $2.5 million reflected within other assets in the accompanying consolidated balance sheets because we may be deemed to exercise significant influence over the operations of Fusion.

On May 19, 2017, we terminated our distribution agreement with Sheen Man Co., Ltd. and Sugan Co, Ltd., ("Sugan"), a Japanese medical device distributor and entered into a business purchase agreement, distribution agreement and a supply agreement with Sugan. Pursuant to these agreements, we acquired the customer list Sugan used in the distribution of our products in Japan. The purchase price is recorded as a customer list intangible asset of approximately $1.2 million. We are amortizing the customer list intangible asset on an accelerated basis over five years. In addition, we granted to Sugan the right to continue to distribute a limited number of our products, related to fluid administration, through December 31, 2021 and to manufacture and sell to Sugan certain contrast injector products during a term of four years, subject to extensions.

On May 1, 2017, we entered into an agreement and plan of merger with Vascular Access Technologies, Inc. ("VAT"), pursuant to which we acquired the SAFECVAD™ device. We accounted for this acquisition as a business combination. The purchase price for the business was $5.0 million. We also recorded $4.9 million of contingent consideration related to royalties potentially payable to VAT pursuant to the merger agreement. The following table summarizes the purchase price allocated to the net assets acquired and liabilities assumed (in thousands):



Intangibles
Developed technology	$	7,800
In-process technology	920
Goodwill	4,281
Deferred tax liabilities	(3,101		)

Total net assets acquired	$	9,900

We are amortizing the developed technology intangible asset over 15 years. The sales and results of operations related to the acquisition have been included in our cardiovascular segment since the acquisition date and were not material. Acquisition-related costs associated with the VAT acquisition, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were not material.

On January 31, 2017, we acquired Argon’s critical care division, including a manufacturing facility in Singapore, the related commercial operations in Europe and Japan, and certain inventories and intellectual property rights within the U.S. We made an initial payment of approximately $10.9 million and received a subsequent reduction to the purchase price of approximately $797,000 related to a working capital adjustment according to the terms of the purchase agreement. We accounted for the acquisition as a business combination.

Acquisition-related costs associated with the acquisition of the Argon critical care division during the year ended December 31, 2017, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were approximately $2.6 million. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018 and 2017, our net sales of the Argon critical care products were approximately $45.5 million and $41.2 million, respectively. It is not practical to separately report the earnings related to the Argon critical care acquisition, as we cannot split out sales costs related solely to the products we acquired from Argon, principally because our sales representatives sell multiple products (including the products we acquired from Argon) in our cardiovascular business segment.

The assets and liabilities in the purchase price allocation for the Argon critical care acquisition are stated at fair value based on estimates of fair value using available information and making assumptions our management believes are reasonable. The following table summarizes the purchase price allocated to the net tangible and intangible assets acquired and liabilities assumed (in thousands):



	Assets Acquired
	Cash and cash equivalents	$	1,436
	Trade receivables	8,351
	Inventories	11,222
	Prepaid expenses and other assets	1,275
	Income tax refund receivable	165
	Property and equipment	2,319
	Deferred tax assets	202
	Intangibles
	Developed technology	2,200
	Customer lists	1,500
	Trademarks	900
	Total assets acquired	29,570

	Liabilities Assumed
	Trade payables	(2,414		)
	Accrued expenses	(5,083		)
	Income taxes payable	—
	Deferred income tax liabilities	(934		)
	Total liabilities assumed	(8,431		)

	Total net assets acquired	21,139
	Gain on bargain purchase ⁽¹⁾	(11,039		)
	Total purchase price	$	10,100

(1)	The total fair value of the net assets acquired from Argon exceeded the purchase price, resulting in a gain on bargain purchase which was recorded within other income (expense) in our consolidated statements of income. We believe the reason for the gain on bargain purchase was a result of the divestiture of a non-strategic, slow-growth critical care business for Argon. It is our understanding that the divestiture allows Argon to focus on its higher growth interventional portfolio.

With respect to the Argon critical care assets, we are amortizing developed technology over seven years and customer lists on an accelerated basis over five years. While U.S. trademarks can be renewed indefinitely, we currently estimate that we will generate cash flow from the acquired trademarks for a period of five years from the acquisition date. The total weighted-average amortization period for these acquired intangible assets is 6.0 years.

On January 31, 2017, we acquired substantially all the assets, including intellectual property covered by approximately 40 patents and pending applications, and assumed certain liabilities, of Catheter Connections, Inc. (“Catheter Connections”), in exchange for payment of $38.0 million. Catheter Connections, based in Salt Lake City, Utah, developed and marketed the DualCap® System, an innovative family of disinfecting products designed to protect patients from intravenous infections resulting from infusion therapy. We accounted for this acquisition as a business combination.

Acquisition-related costs associated with the Catheter Connections acquisition during the year ended December 31, 2017, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were approximately $482,000. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018 and 2017, our net sales of the products acquired from Catheter Connections were approximately $13.7 million and $10.0 million, respectively. It is not practical to separately report the earnings related to the products acquired from Catheter Connections, as we cannot split out sales costs related solely to those products, principally because our sales representatives sell multiple products (including the DualCap System) in the cardiovascular business segment. The purchase price was allocated as follows (in thousands):



Assets Acquired
Trade receivables	$	958
Inventories	2,157
Prepaid expenses and other assets	85
Property and equipment	1,472
Intangibles
Developed technology	21,100
Customer lists	700
Trademarks	2,900
Goodwill	8,989
Total assets acquired	38,361

Liabilities Assumed
Trade payables	(338		)
Accrued expenses	(23		)
Total liabilities assumed	(361		)

Net assets acquired	$	38,000

We are amortizing the Catheter Connections developed technology asset over 12 years, the related trademarks over ten years, and the associated customer list over eight years. We have estimated the weighted average life of the intangible Catheter Connections assets acquired to be approximately 11.7 years.

On December 19, 2016, we paid $5.0 million for 1,251,878 shares of common stock and a distribution agreement with Bluegrass Vascular Technologies, Inc. ("Bluegrass"). The common stock, which represents an ownership interest of approximately 19.5%, has been accounted for as a cost method investment of $4.0 million reflected within other assets in the accompanying consolidated balance sheets because we are not able to exercise significant influence over the operations of Bluegrass. The distribution agreement intangible asset was valued at $1.0 million and will be amortized over a period of three years.

On July 6, 2016, we acquired all of the issued and outstanding shares of DFINE Inc. ("DFINE"). The DFINE acquisition added a line of vertebral augmentation products for the treatment of vertebral compression fractures ("VCF") as well as medical devices used to treat metastatic spine tumors. We made an initial payment of $97.5 million to certain DFINE stockholders on July 6, 2016 and paid approximately $578,000 related to a net working capital adjustment subject to review by Merit and the preferred stockholders of DFINE. We accounted for the acquisition as a business combination. In the three-month period ended December 31, 2016, we negotiated the final net working capital adjustment resulting in a reduction to the purchase price of approximately $1.1 million. As a result, we recorded measurement period adjustments to reduce inventories by approximately $89,000, reduce property and equipment by approximately $109,000, reduce goodwill by approximately $1.2 million, reduce accrued expenses by approximately $407,000 and increase the associated deferred tax liabilities by approximately $113,000. Under U.S. GAAP, measurement period adjustments are recognized on a prospective basis in the period of change, instead of restating prior periods. There was no impact to reported earnings in connection with these measurement period adjustments.

Acquisition-related costs during the year ended December 31, 2016, which are included in selling, general, and administrative expenses in the accompanying consolidated statements of income, were approximately $1.6 million. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018, 2017 and 2016, our net sales of DFINE products were approximately $26.6 million, $27.0 million and $13.5 million, respectively. It is not practical to separately report the earnings related to the DFINE acquisition, as we cannot split out sales costs related to DFINE products, principally because our sales representatives are selling multiple products (including DFINE products) in the cardiovascular business segment.

The purchase price was allocated to the net tangible and intangible assets acquired and liabilities assumed, based on estimated fair values, as follows (in thousands):



Assets Acquired
Trade receivables	$	4,054
Other receivables	6
Inventories	8,585
Prepaid expenses	630
Property and equipment	1,630
Other long-term assets	145
Intangibles
Developed technology	67,600
Customer lists	2,400
Trademarks	4,400
Goodwill	24,818
Total assets acquired	114,268

Liabilities Assumed
Trade payables	(1,790		)
Accrued expenses	(5,298		)
Deferred income tax liabilities - current	(701		)
Deferred income tax liabilities - noncurrent	(10,844		)
Total liabilities assumed	(18,633		)

Net assets acquired, net of cash received of $1,327	$	95,635

The gross amount of trade receivables we acquired in the acquisition was approximately $4.3 million, of which approximately $224,000 was expected to be uncollectible or returned. With respect to the DFINE assets, we are amortizing developed technology over 15 years and customer lists on an accelerated basis over nine years. While U.S. trademarks can be renewed indefinitely, we currently estimate that we will generate cash flow from the acquired trademarks for a period of 15 years from the acquisition date. The total weighted-average amortization period for these acquired intangible assets is 14.8 years.

On February 4, 2016, we purchased the HeRO® Graft device and other related assets from CryoLife, Inc., a developer of medical devices based in Kennesaw, Georgia ("CryoLife"). The HeRO Graft is a fully subcutaneous vascular access system intended for use in maintaining long-term vascular access for chronic hemodialysis patients who have failing fistulas, grafts or are catheter dependent due to a central venous blockage. The purchase price was $18.5 million, which was paid in full during 2016. We accounted for this acquisition as a business combination. The purchase price was allocated as follows (in thousands):



Assets Acquired
Inventories	$	2,455
Property and equipment	290
Intangibles
Developed technology	12,100
Trademarks	700
Customers Lists	400
Goodwill	2,555

Total assets acquired	$	18,500

We are amortizing the developed HeRO Graft technology asset over ten years, the related trademarks over 5.5 years, and the associated customer lists over 12 years. We have estimated the weighted average life of the intangible HeRO Graft assets acquired to be approximately 9.8 years. Acquisition-related costs related to the HeRO Graft device and other related assets during the year ended December 31, 2016, which are included in selling, general and administrative expenses in the accompanying consolidated statements of income, were not material. The results of operations related to this acquisition have been included in our cardiovascular segment since the acquisition date. During the years ended December 31, 2018, 2017 and 2016, our net sales of the products acquired from CryoLife were approximately $9.1 million, $8.6 million and $7.1 million, respectively. It is not practical to separately

report the earnings related to the products acquired from CryoLife, as we cannot split out sales costs related to those products, principally because our sales representatives are selling multiple products (including the HeRO Graft device) in the cardiovascular business segment.

The following table summarizes our consolidated results of operations for the years ended December 31, 2018, 2017 and 2016, as well as unaudited pro forma consolidated results of operations as though the DFINE acquisition had occurred on January 1, 2015, the acquisition of the Argon critical care division had occurred on January 1, 2016 and the acquisition of Cianna Medical and Vascular Insights had occurred on January 1, 2017 (in thousands, except per common share amounts):



	2018				2017					2016
	As Reported		Pro Forma		As Reported		Pro Forma			As Reported		Pro Forma
Net sales	$	882,753	$	928,336	$	727,852	$	768,571		$	603,838	$	664,366
Net income (loss)	42,017		20,699		27,523		(13,720		)	20,121		23,054
Earnings per common share:
Basic	$	0.80	$	0.40	$	0.56	$	(0.28	)	$	0.45	$	0.52
Diluted	$	0.78	$	0.38	$	0.55	$	(0.27	)	$	0.45	$	0.51

The unaudited pro forma information set forth above is for informational purposes only and includes adjustments related to the

step-up of acquired inventories, amortization expense of acquired intangible assets, stock-based compensation for cancelled or forfeited options, interest expense on long-term debt and changes in the timing of the recognition of the gain on bargain purchase. The pro forma information should not be considered indicative of actual results that would have been achieved if the acquisition of Cianna Medical and Vascular Insights had occurred on January 1, 2017, the acquisition of the Argon critical care division had occurred on January 1, 2016, or the acquisition of DFINE had occurred on January 1, 2015, or results that may be obtained in any future period. The pro forma consolidated results of operations do not include the acquisition of assets from BD because it was deemed impracticable to obtain information to determine net income associated with the acquired product lines which represent a small product line of a large, consolidated company without standalone financial information. The pro forma consolidated results of operations do not include the DirectACCESS, ITL, Laurane, Osseon, VAT, Catheter Connections or HeRO Graft acquisitions as we do not deem the pro forma effect of these transactions to be material.

The goodwill arising from the acquisitions discussed above consists largely of the synergies and economies of scale we hope to achieve from combining the acquired assets and operations with our historical operations (see Note 5). The goodwill recognized from certain acquisitions is expected to be deductible for income tax purposes.

Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

GOODWILL AND INTANGIBLE ASSETS

The changes in the carrying amount of goodwill for the years ended December 31, 2018 and 2017, are as follows (in thousands):



	2018			2017
Goodwill balance at January 1	$	238,147		$	211,927
Effect of foreign exchange	(1,304		)	2,641
Additions as the result of acquisitions	98,590			23,579
Goodwill balance at December 31	$	335,433		$	238,147

Total accumulated goodwill impairment losses aggregated to $8.3 million as of December 31, 2018 and 2017. We did not have any goodwill impairments for the years ended December 31, 2018, 2017 and 2016. The total goodwill balance as of December 31, 2018 and 2017, is related to our cardiovascular segment.

Other intangible assets at December 31, 2018 and 2017, consisted of the following (in thousands):



	2018
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Patents	$	19,378	$	(5,012	)	$	14,366
Distribution agreements	8,012		(5,766		)	2,246
License agreements	26,930		(7,411		)	19,519
Trademarks	29,998		(6,586		)	23,412
Covenants not to compete	1,028		(1,000		)	28
Customer lists	39,936		(23,361		)	16,575
In-process technology	3,420		—			3,420

Total	$	128,702	$	(49,136	)	$	79,566



	2017
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Patents	$	16,528	$	(3,737	)	$	12,791
Distribution agreements	7,262		(4,686		)	2,576
License agreements	23,783		(5,568		)	18,215
Trademarks	16,224		(4,686		)	11,538
Covenants not to compete	1,028		(968		)	60
Customer lists	31,935		(18,482		)	13,453
In-process technology	920		—			920

Total	$	97,680	$	(38,127	)	$	59,553

Aggregate amortization expense for the years ended December 31, 2018, 2017 and 2016 was approximately $41.2 million, $26.8 million and $19.3 million, respectively.

We evaluate long-lived assets, including amortizing intangible assets, for impairment whenever events or changes in circumstances indicate that their carrying amounts may not be recoverable. We perform the impairment analysis at the asset group for which the lowest level of identifiable cash flows are largely independent of the cash flows of other assets and liabilities. We compare the carrying value of the amortizing intangible assets acquired to the undiscounted cash flows expected to result from the asset group and determine whether the carrying amount is recoverable. We determine the fair value of our amortizing assets based on estimated future cash flows discounted back to their present value using a discount rate that reflects the risk profiles of the underlying activities. During the years ended December 31, 2018 and 2017, we recorded impairment charges of $657,000, related to our July 2015 acquisition of certain assets from Quellent, LLC, and $809,000, related to our July 2015 acquisition of certain assets from Distal Access, LLC, respectively, all of which pertained to our cardiovascular segment. Some of the factors that influenced our estimated cash flows were slower than anticipated sales growth in the products acquired from our Quellent and Distal Access acquisitions and uncertainty about future sales growth. We did not record any impairment charges during the year ended December 31, 2016.

Estimated amortization expense for the developed technology and other intangible assets for the next five years consists of the following as of December 31, 2018 (in thousands):



Year Ending December 31
2019	$	58,035
2020	55,341
2021	48,084
2022	46,648
2023	45,417

Income Taxes

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Income Taxes

INCOME TAXES

On December 22, 2017, U.S. federal tax legislation, commonly referred to as the Tax Cuts and Jobs Act (“TCJA”) was signed into law. Significant provisions that have impacted (and will in the future impact) our effective tax rate include the reduction in the corporate tax rate from 35% to 21%, effective in 2018; a one-time deemed repatriation (“transition tax”) on earnings of certain foreign subsidiaries that were previously tax deferred; and new taxes on certain foreign sourced earnings. At December 31, 2017, we had not completed our accounting for the tax effects of the TCJA; however, in certain cases, as described below, we made reasonable estimates of the effects on our existing deferred tax balances and impact of the one-time transition tax. In accordance with SEC Staff Accounting Bulletin 118 (“SAB 118”), income tax effects of the TCJA may be refined upon obtaining, preparing, and/or analyzing additional information during the measurement period and such changes could be material. During the measurement period, provisional amounts may also be adjusted for the effects, if any, of interpretative guidance issued after December 31, 2017, by U.S. regulatory and standard-setting bodies.

As of December 31, 2017, we were able to determine a reasonable estimate and recognize the provisional impacts of the rate reduction on our existing deferred tax balances and the impact of the transition tax. The reduction in the U.S. corporate tax rate resulted in a net tax benefit of approximately $8.4 million related to the revaluation of our U.S. net deferred tax liability. The transition tax resulted in a one-time tax expense of approximately $10.6 million.

As of December 31, 2018, we have revised these estimated amounts based upon further analysis of the TCJA and notices and regulations issued and proposed by the U.S. Department of Treasury and the Internal Revenue Service. We recognized an additional tax benefit of approximately $71,000 on the difference between the 2017 U.S. enacted tax rate of 35%, and the 2018 enacted tax rate of 21%. We recognized a tax benefit of approximately $3.3 million from the revised transition tax calculation, which included the completion of our calculation of the total post-1986 foreign earnings and profits (“E&P”) of our foreign subsidiaries, and related foreign tax credits. We elected to pay our transition tax over the eight-year period provided by the TCJA.

For tax years beginning after December 31, 2017, the TCJA introduces new provisions of U.S. taxation of certain Global Intangible Low-Tax Income (“GILTI”). The FASB provided guidance that companies should make an accounting policy election to either treat taxes on GILTI as period costs or use the deferred method. We have elected to treat taxes on GILTI as period costs and recognized tax expense of approximately $347,000 in December 2018.

As of December 31, 2018, we have completed our accounting for the tax effects of the enactment of the TCJA; however, we continue to expect U.S. regulatory and standard-setting bodies to issue guidance and regulations that could have a material financial statement impact on our effective tax rate in future periods.

We have historically asserted indefinite reinvestment of the earnings of certain non-U.S. subsidiaries outside the U.S. The TCJA eliminated certain material tax effects on the repatriation of cash to the U.S. As such, future repatriation of cash and other property held by our foreign subsidiaries will generally not be subject to U.S. federal income tax. Therefore, after reevaluation of the permanent reinvestment assertion, we no longer consider our foreign earnings to be permanently reinvested as of December 31, 2018. As a result of the change in the assertion, during 2018 we recorded tax expense of approximately $5.6 million for foreign withholding taxes on unremitted foreign earnings as of December 31, 2018.

For the years ended December 31, 2018, 2017 and 2016, income before income taxes is broken out between U.S. and foreign-sourced operations and consisted of the following (in thousands):



	2018		2017		2016
Domestic	$	21,084	$	14,531	$	6,174
Foreign	28,435		21,350		19,212
Total	$	49,519	$	35,881	$	25,386

The components of the provision for income taxes for the years ended December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018			2017			2016
Current expense (benefit):
Federal	$	(1,132	)	$	3,849		$	1,933
State	582			645			492
Foreign	6,000			5,168			3,802
Total current expense	5,450			9,662			6,227

Deferred expense (benefit):
Federal	4,400			(314		)	(144		)
State	(667		)	(216		)	(195		)
Foreign	(1,681		)	(774		)	(623		)
Total deferred (benefit) expense	2,052			(1,304		)	(962		)

Total income tax expense	$	7,502		$	8,358		$	5,265

The difference between the income tax expense reported and amounts computed by applying the statutory federal rate of 21.0% to pretax income for the year ended December 31, 2018, and 35% for years ended December 31, 2017 and 2016, consisted of the following (in thousands):



	2018			2017			2016
Computed federal income tax expense at applicable statutory rate	$	10,399		$	12,559		$	8,885
State income taxes	(59		)	279			193
Tax credits	(1,734		)	(1,377		)	(1,164		)
Production activity deduction	—			—			(53		)
Foreign tax rate differential	(1,361		)	(3,329		)	(3,717		)
Uncertain tax positions	267			(19		)	597
Deferred compensation insurance assets	186			(479		)	(307		)
Transaction-related expenses	223			90			274
U.S. transition tax	(3,271		)	10,612			—
TCJA remeasurement of deferred taxes	(71		)	(8,383		)	—
Stock-based payments	(4,278		)	(2,264		)	—
Bargain purchase gain	—			(1,570		)	—
In-process research and development	—			1,486			—
Net GILTI	347			—			—
Foreign withholding tax	5,590			—			—
Other — including the effect of graduated rates	1,264			753			557
Total income tax expense	$	7,502		$	8,358		$	5,265

Deferred income tax assets and liabilities at December 31, 2018 and 2017, consisted of the following temporary differences and carry-forward items (in thousands):



	2018			2017
Deferred income tax assets:
Allowance for uncollectible accounts receivable	$	606		$	467
Accrued compensation expense	7,414			5,154
Inventory differences	1,269			2,505
Net operating loss carryforwards	20,226			15,741
Deferred revenue	46			58
Stock-based compensation expense	2,833			2,281
Other	9,243			8,986
Total deferred income tax assets	41,637			35,192

Deferred income tax liabilities:
Prepaid expenses	(1,142		)	(930		)
Property and equipment	(20,045		)	(20,352		)
Intangible assets	(58,883		)	(28,588		)
Foreign withholding tax	(5,590		)	—
Other	(4,350		)	(1,830		)
Total deferred income tax liabilities	(90,010		)	(51,700		)
Valuation allowance	(4,989		)	(4,422		)
Net deferred income tax assets (liabilities)	$	(53,362	)	$	(20,930	)

Reported as:
Deferred income tax assets - Long-term	$	3,001		$	2,359
Deferred income tax liabilities - Long-term	(56,363		)	(23,289		)
Net deferred income tax liabilities	$	(53,362	)	$	(20,930	)

The long-term deferred income tax balances are not netted as they represent deferred amounts applicable to different taxing jurisdictions. Deferred income tax balances reflect the temporary differences between the carrying amounts of assets and liabilities and their tax basis and are stated at enacted tax rates expected to be in effect when taxes are actually paid or recovered.

The valuation allowance is primarily related to state credit carryforwards, non-US net operating loss carryforwards, and capital loss carryforwards for which we believe it is more likely than not that the deferred tax assets will not be realized. The valuation allowance increased by approximately $567,000, $636,000 and $1.8 million during the years ended December 31, 2018, 2017 and 2016, respectively.

As of December 31, 2018 and 2017, we had U.S federal net operating loss carryforwards of approximately $86.3 million and $67.9 million, respectively, which were generated by Cianna Medical, VAT, DFINE and Biosphere Medical, Inc. prior to our acquisition of these companies. Cianna Medical, Inc. was acquired on November 13, 2018. These net operating loss carryforwards, which expire at various dates through 2035, are subject to an annual limitation under Internal Revenue Code Section 382. We anticipate that we will utilize the net operating loss carryforwards over the next 17 years. We utilized a total of approximately $11.9 million and $9.1 million in U.S. federal net operating loss carryforwards during the years ended December 31, 2018 and 2017, respectively.

As of December 31, 2018, we had approximately $5.9 million of non-U.S. net operating loss carryforwards, of which approximately $5.2 million have no expiration date and approximately $761,000 expire at various dates through 2027. As of December 31, 2017, we had $5.4 million of non-U.S. net operating loss carryforwards, of which approximately $4.9 million had no expiration date and approximately $526,000 expire at various dates through 2027. Non-U.S. net operating loss carryforwards utilized during the years ended December 31, 2018 and 2017 were not material.

We are subject to income taxes in the U.S. and numerous foreign jurisdictions. Significant judgment is required in determining our worldwide provision for income taxes and recording the related assets and liabilities. In the ordinary course of our business, there are many transactions and calculations where the ultimate tax determination is uncertain. In our opinion, we have made adequate provisions for income taxes for all years subject to audit. We are no longer subject to U.S. federal, state, and local income tax examinations by tax authorities for years before 2015. In foreign jurisdictions, we are no longer subject to income tax examinations for years before 2012.

Although we believe our estimates are reasonable, the final outcomes of these matters may be different from those which we have reflected in our historical income tax provisions and accruals. Such differences could have a material effect on our income tax provision and operating results in the period in which we make such determination.

The total liability for unrecognized tax benefits at December 31, 2018, including interest and penalties, was approximately $3.3 million, of which approximately $3.0 million would favorably impact our effective tax rate if recognized. The total liability for unrecognized tax benefits at December 31, 2017, including interest and penalties, was approximately $3.1 million, of which approximately $2.7 million would favorably impact our effective tax rate if recognized. As of December 31, 2018 and 2017, the total liability for uncertain tax benefits, as presented on our consolidated balance sheets, has been reduced by approximately $307,000 related to certain liabilities for unrecognized tax benefits, which, if realized, would reduce the transition tax under the TCJA by approximately $307,000. As of December 31, 2018 and 2017, we had accrued approximately $373,000 and $304,000 respectively, in total interest and penalties related to unrecognized tax benefits. We account for interest and penalties for unrecognized tax benefits as part of our income tax provision. During the years ended December 31, 2018, 2017 and 2016, we added interest and penalties of approximately $69,000, $88,000 and $30,000, respectively, to our liability for unrecognized tax benefits. It is reasonably possible that within the next 12 months the total liability for unrecognized tax benefits may change, net of potential decreases due to the expiration of statutes of limitation, up to $400,000.

A reconciliation of the beginning and ending amount of liabilities associated with uncertain tax benefits for the years ended December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



Tabular Roll-forward	2018			2017			2016

Unrecognized tax benefits, opening balance	$	2,749		$	2,549		$	1,982
Gross increases in tax positions taken in a prior year	35			80			77
Gross increases in tax positions taken in the current year	586			403			856
Lapse of applicable statute of limitations	(423		)	(283		)	(366		)
Unrecognized tax benefits, ending balance	$	2,947		$	2,749		$	2,549

The tabular roll-forward ending balance does not include interest and penalties related to unrecognized tax benefits.

Revolving Credit Facility and Long-Term Debt

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Revolving Credit Facility and Long-Term Debt

REVOLVING CREDIT FACILITY AND LONG-TERM DEBT

Principal balances outstanding under our long-term debt obligations as of December 31, 2018 and 2017, consisted of the following (in thousands):



	2018			2017
2016 Term loan	$	72,500		$	85,000
2016 Revolving credit loans	316,000			187,000
Collateralized debt facility	7,000			6,959
Less unamortized debt issuance costs	(348		)	(487		)
Total long-term debt	395,152			278,472
Less current portion	22,000			19,459
Long-term portion	$	373,152		$	259,013

Collateralized Debt Facility

On September 3, 2018, we renewed our loan agreement with HSBC Bank USA, National Association ("HSBC Bank") whereby HSBC Bank agreed to provide us with a loan in the amount of $7.0 million. As of December 31, 2018 the loan was set to mature on January 11, 2019, with an extension available at our option, subject to certain conditions. In January 2019, we entered into an agreement to extend the loan agreement through April 28, 2019. The loan agreement bears interest at the six-month London Inter-Bank Offered Rate (“LIBOR”) plus 1.0%. The loan is secured by assets equal to the currently outstanding loan balance. The loan contains covenants, representations and warranties and other terms customary for loans of this nature. As of December 31, 2018, our interest rate on the loan was a variable rate of 3.39%.

2016 Term Loan and Revolving Credit Loans

On July 6, 2016, we entered into a Second Amended and Restated Credit Agreement (as amended to date, the “Second Amended Credit Agreement”), with Wells Fargo Bank, National Association, as administrative agent, swingline lender and a lender, and Wells Fargo Securities, LLC, as sole lead arranger and sole bookrunner. In addition to Wells Fargo Bank, National Association, Bank of America, N.A., U.S. Bank, National Association, and HSBC Bank USA, National Association, are parties to the Second Amended Credit Agreement as lenders. The Second Amended Credit Agreement amends and restates in its entirety our previously outstanding Amended and Restated Credit Agreement and all amendments thereto. The Second Amended Credit Agreement was amended on September 28, 2016 to allow for a new revolving credit loan to our wholly-owned subsidiary, on March 20, 2017 to allow flexibility in how we apply net proceeds received from equity issuances to prepay outstanding indebtedness, on December 13, 2017 to increase the revolving credit commitment by $100 million up to $375 million, and on March 28, 2018 to amend certain debt covenants.

The Second Amended Credit Agreement provides for a term loan of $150 million and a revolving credit commitment up to an aggregate amount of $375 million, which includes a reserve of $25 million to make swingline loans from time to time. The term loan is payable in quarterly installments in the amounts provided in the Second Amended Credit Agreement until the maturity date of July 6, 2021, at which time the term and revolving credit loans, together with accrued interest thereon, will be due and payable. At any time prior to the maturity date, we may repay any amounts owing under all revolving credit loans, term loans, and all swingline loans in whole or in part, subject to certain minimum thresholds, without premium or penalty, other than breakage costs.

Revolving credit loans denominated in dollars and term loans made under the Second Amended Credit Agreement bear interest, at our election, at either a Base Rate or Eurocurrency Base Rate (as such terms are defined in the Second Amended Credit Agreement) plus the applicable margin, which increases as our Consolidated Total Leverage Ratio (as defined in the Second Amended Credit Agreement) increases. Revolving credit loans denominated in an Alternative Currency (as defined in the Second Amended Credit Agreement) bear interest at the Eurocurrency rate plus the applicable margin. Swingline loans bear interest at the base rate plus the applicable margin. Upon an event of default, the interest rate may be increased by 2.0%. The revolving credit commitment will also carry a commitment fee of 0.15% to 0.40% per annum on the unused portion.

The Second Amended Credit Agreement is collateralized by substantially all our assets. The Second Amended Credit Agreement contains covenants, representations and warranties and other terms customary for loans of this nature. The Second Amended Credit Agreement requires that we maintain certain financial covenants, as follows:



		Covenant Requirement
Consolidated Total Leverage Ratio (1)
	January 1, 2018 and thereafter	3.5 to 1.0
Consolidated EBITDA (2)		1.25 to 1.0
Consolidated Net Income (3)		$—
Facility Capital Expenditures (4)		$30 million

(1)	Maximum Consolidated Total Leverage Ratio (as defined in the Second Amended Credit Agreement) as of any fiscal quarter end.
(2)	Minimum ratio of Consolidated EBITDA (as defined in the Second Amended Credit Agreement and adjusted for certain expenditures) to Consolidated Fixed Charges (as defined in the Second Amended Credit Agreement) for any period of four consecutive fiscal quarters.
(3)	Minimum level of Consolidated Net Income (as defined in the Second Amended Credit Agreement) for certain periods, and subject to certain adjustments.
(4)	Maximum level of the aggregate amount of all Facility Capital Expenditures (as defined in the Second Amended Credit Agreement) in any fiscal year.

Additionally, the Second Amended Credit Agreement contains customary events of default and affirmative and negative covenants for transactions of this type. As of December 31, 2018, we believe we were in compliance with all covenants set forth in the Second Amended Credit Agreement.

Future Payments

Future minimum principal payments on our long-term debt as of December 31, 2018, are as follows (in thousands):



Years Ending	Future Minimum
December 31	Principal Payments
2019	22,000
2020	17,500
2021	356,000
Total future minimum principal payments	$	395,500

As of December 31, 2018, we had outstanding borrowings of approximately $388.5 million under the Second Amended Credit Agreement, with available borrowings of approximately $58.3 million, based on the leverage ratio required pursuant to the Second Amended Credit Agreement. Our interest rate as of December 31, 2018 was a fixed rate of 2.12% on $175.0 million as a result an interest rate swap (see Note 9) and a variable floating rate of 3.52% on $213.5 million. Our interest rate as of December 31, 2017 was a fixed rate of 2.68% on $175.0 million as a result of an interest rate swap and a variable floating rate of 2.82% on $97.0 million.

Derivatives

12 Months Ended

Dec. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivatives

DERIVATIVES

General. Our earnings and cash flows are subject to fluctuations due to changes in interest rates and foreign currency exchange rates, and we seek to mitigate a portion of these risks by entering into derivative contracts. The derivatives we use are interest rate swaps and foreign currency forward contracts. We recognize derivatives as either assets or liabilities at fair value in

the accompanying consolidated balance sheets, regardless of whether or not hedge accounting is applied. We report cash flows arising from our hedging instruments consistent with the classification of cash flows from the underlying hedged items. Accordingly, cash flows associated with our derivative programs are classified as operating activities in the accompanying consolidated statements of cash flows.

We formally document, designate and assess the effectiveness of transactions that receive hedge accounting initially and on an ongoing basis. Changes in the fair value of derivatives that qualify for hedge accounting treatment are recorded, net of applicable taxes, in accumulated other comprehensive income, a component of stockholders’ equity in the accompanying consolidated balance sheets. For the ineffective portions of qualifying hedges, the change in fair value is recorded through earnings in the period of change. Changes in the fair value of derivatives not designated as hedging instruments are recorded in earnings throughout the term of the derivative.

Interest Rate Risk. A portion of our debt bears interest at variable interest rates and, therefore, we are subject to variability in the cash paid for interest expense. In order to mitigate a portion of this risk, we use a hedging strategy to reduce the variability of cash flows in the interest payments associated with a portion of the variable-rate debt outstanding under our Second Amended Credit Agreement that is solely due to changes in the benchmark interest rate.

Derivatives Designated as Cash Flow Hedges

On August 5, 2016, we entered into a pay-fixed, receive-variable interest rate swap with a current notional amount of $175.0 million with Wells Fargo to fix the one-month LIBOR rate at 1.12%. The variable portion of the interest rate swap is tied to the one-month LIBOR rate (the benchmark interest rate). On a monthly basis, the interest rates under both the interest rate swap and the underlying debt reset, the swap is settled with the counterparty, and interest is paid. The interest rate swap is scheduled to expire on July 6, 2021.

At December 31, 2018 and 2017, our interest rate swap qualified as a cash flow hedge. The fair value of our interest rate swap at December 31, 2018 was an asset of approximately $5.8 million, which was partially offset by approximately $1.5 million in deferred taxes. The fair value of our interest rate swaps at December 31, 2017 was an asset of approximately $5.7 million, which was offset by approximately $1.5 million in deferred taxes.

Foreign Currency Risk. We operate on a global basis and are exposed to the risk that our financial condition, results of operations, and cash flows could be adversely affected by changes in foreign currency exchange rates. To reduce the potential effects of foreign currency exchange rate movements on net earnings, we enter into derivative financial instruments in the form of foreign currency exchange forward contracts with major financial institutions. Our policy is to enter into foreign currency derivative contracts with maturities of up to two years. We are primarily exposed to foreign currency exchange rate risk with respect to transactions and balances denominated in Euros, British Pounds, Chinese Renminbi, Mexican Pesos, Brazilian Reals, Australian Dollars, Hong Kong Dollars, Swiss Francs, Swedish Krona, Canadian Dollars, Danish Krone, Japanese Yen, Korea Won, and Singapore Dollars, among others. We do not use derivative financial instruments for trading or speculative purposes. We are not subject to any credit risk contingent features related to our derivative contracts, and counterparty risk is managed by allocating derivative contracts among several major financial institutions.

Derivatives Designated as Cash Flow Hedges

For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative instrument is reported as a component of other comprehensive income (loss) and reclassified into earnings in the same line item associated with the forecasted transaction and in the same period or periods during which the hedged transaction affects earnings. The remaining gain or loss on the derivative instrument in excess of the cumulative change in the present value of future cash flows of the hedged item, if any (i.e., the ineffective portion) or hedge components excluded from the assessment of effectiveness, are recognized in earnings during the current period. We entered into forward contracts on various foreign currencies to manage the risk associated with forecasted exchange rates which impact revenues, cost of sales, and operating expenses in various international markets. The objective of the hedges is to reduce the variability of cash flows associated with the forecasted purchase or sale of the associated foreign currencies.

We enter into approximately 150 cash flow foreign currency hedges every month. As of December 31, 2018, we had entered into foreign currency forward contracts, which qualified as cash flow hedges, with the following notional amounts (in thousands and in local currencies):



Currency	Symbol	Forward Notional Amount
Australian Dollar	AUD	3,000
Canadian Dollar	CAD	4,410
Swiss Franc	CHF	2,145
Chinese Renminbi	CNY	160,000
Danish Krone	DKK	17,225
Euro	EUR	20,310
British Pound	GBP	5,280
Japanese Yen	JPY	1,145,000
Korean Won	KRW	3,050,000
Mexican Peso	MXN	230,000
Swedish Krona	SEK	30,210

Derivatives Not Designated as Cash Flow Hedges

We forecast our net exposure in various receivables and payables to fluctuations in the value of various currencies, and we enter into foreign currency forward contracts to mitigate that exposure. We enter into approximately 20 foreign currency fair value hedges every month. As of December 31, 2018, we had entered into foreign currency forward contracts related to those balance sheet accounts with the following notional amounts (in thousands and in local currencies):



Currency	Symbol	Forward Notional Amount
Australian Dollar	AUD	11,400
Brazilian Real	BRL	9,000
Canadian Dollar	CAD	2,300
Swiss Franc	CHF	269
Chinese Renminbi	CNY	63,200
Danish Krone	DKK	3,237
Euro	EUR	5,927
British Pound	GBP	2,358
Hong Kong Dollar	HKD	11,000
Japanese Yen	JPY	265,000
Korean Won	KRW	5,500,000
Mexican Peso	MXN	23,000
Swedish Krona	SEK	9,627
Singapore Dollar	SGD	8,500

Balance Sheet Presentation of Derivatives. As of December 31, 2018 and 2017, all derivatives, both those designated as hedging instruments and those that were not designated as hedging instruments, were recorded gross at fair value on our consolidated balance sheets. We are not subject to any master netting agreements.

The fair value of derivative instruments on a gross basis is as follows (in thousands):



		Fair Value
	Balance Sheet Location	December 31, 2018			December 31, 2017
Derivatives designated as hedging instruments
Assets
Interest rates swaps	Other assets (long-term)	$	5,772		$	5,749
Foreign currency forward contracts	Prepaid expenses and other assets	613			363
Foreign currency forward contracts	Other assets (long-term)	151			35

Liabilities
Foreign currency forward contracts	Accrued expenses	(711		)	(468		)
Foreign currency forward contracts	Other long-term obligations	(101		)	(82		)

Derivatives not designated as hedging instruments
Assets
Foreign currency forward contracts	Prepaid expenses and other assets	$	814		$	223
Liabilities
Foreign currency forward contracts	Accrued expenses	(796		)	(841		)

Income Statement Presentation of Derivatives

Derivatives Designated as Cash Flow Hedges

Derivative instruments designated as cash flow hedges had the following effects, before income taxes, on other comprehensive income ("OCI"), accumulated other comprehensive income ("AOCI") and net earnings in our consolidated statements of income, consolidated statements of comprehensive income and consolidated balance sheets (in thousands):



	Amount of Gain/(Loss) recognized in OCI							Amount of Gain/(Loss) reclassified from AOCI
	Year ended December 31,							Year ended December 31,
	2018	2017		2016				2018	2017		2016
Derivative instrument							Location in statements of income
Interest rate swaps	$1,559	$	853	$	4,989		Interest Expense	$1,537	95		(718	)
Foreign currency forward contracts	539	491		(205		)	Revenue	136	(277	)	21
							Cost of goods sold	361	625		(26	)

The net amount recognized in earnings during the years ended December 31, 2018, 2017 and 2016 due to ineffectiveness and amounts excluded from the assessment of hedge effectiveness were not significant.

As of December 31, 2018, approximately $27,000, or $20,000 after taxes, was expected to be reclassified from accumulated other comprehensive income to earnings in revenue and cost of sales over the succeeding twelve months. As of December 31, 2018, approximately $2.5 million, or $1.9 million after taxes, was expected to be reclassified from accumulated other comprehensive income to earnings in interest expense over the succeeding twelve months.

Derivatives Not Designated as Hedging Instruments

The following gains/(losses) from these derivative instruments were recognized in our consolidated statements of income for the years presented (in thousands):



		Year ended December 31,
		2018		2017			2016
Derivative Instrument	Location in statements of income
Foreign currency forward contracts	Other expense	$	4,147	$	(4,746	)	$	69

See Note 16 for more information about our derivatives.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

COMMITMENTS AND CONTINGENCIES

We are obligated under non-terminable operating leases for manufacturing facilities, finished good distribution centers, office space, equipment and certain vehicles. Total rental expense on these operating leases for the years ended December 31, 2018, 2017 and 2016, approximated $14.5 million, $13.6 million and $11.4 million, respectively.

The future minimum lease payments for operating leases as of December 31, 2018, consisted of the following (in thousands):



Years Ending	Operating
December 31	Leases

2019	$	13,421
2020	11,319
2021	9,995
2022	8,053
2023	6,953
Thereafter	52,754

Total minimum lease payments	$	102,495

Irish Government Development Agency Grants. As of December 31, 2018, we had entered into several grant agreements with the Irish Government Development Agency. Grants related to the acquisition of property and equipment purchased in Ireland are amortized as a reduction to depreciation expense over lives corresponding to the depreciable lives of such property and equipment. The balance of deferred credits related to such grants as of December 31, 2018 and 2017, was approximately $2.3 million and $2.4 million, respectively. During the years ended December 31, 2018, 2017 and 2016, approximately $142,000, $147,000 and $170,000, respectively, of the deferred credit was amortized as a reduction of operating expenses.

We had committed to repay the Irish government for grants received if we cease production in Ireland prior to the expiration of the grant liability period. The grant liability period is usually between five and eight years from the last claim made on a grant. As of December 31, 2018, the grant liability period had expired and there was no remaining amount which the Irish government could reclaim if we were to cease production in Ireland. We have no plans to cease production in Ireland.

Royalties. As of December 31, 2018, we had entered into a number of agreements to license or acquire rights to certain intellectual property which require us to make royalty payments during the term of the agreements generally based on a percentage of sales. Total royalty expense during the years ended December 31, 2018, 2017 and 2016, approximated $5.3 million, $4.4 million and $3.2 million, respectively. Minimum contractual commitments under royalty agreements to be paid within twelve months of December 31, 2018 were not significant. See Note 3 for discussion of future royalty commitments related to acquisitions.

Litigation. In the ordinary course of business, we are involved in various claims and litigation matters. These claims and litigation matters may include actions involving product liability, intellectual property, contract disputes, and employment or other matters that are significant to our business. Based upon our review of currently available information, we do not believe that any such actions are likely to be, individually or in the aggregate, materially adverse to our business, financial condition, results of operations or liquidity.

In addition to the foregoing matters, in October 2016, we received a subpoena from the U.S. Department of Justice seeking information on certain of our marketing and promotional practices. We are in the process of responding to the subpoena, which we anticipate will continue during 2019. We have incurred, and anticipate that we will continue to incur, substantial costs in connection with the matter. The investigation is ongoing and at this stage we are unable to predict its scope, duration or outcome. Investigations such as this may result in the imposition of, among other things, significant damages, injunctions, fines or civil or criminal claims or penalties against our company or individuals.

In the event of unexpected further developments, it is possible that the ultimate resolution of any of the foregoing matters, or other similar matters, if resolved in a manner unfavorable to us, may be materially adverse to our business, financial condition, results of operations or liquidity. Legal costs for these matters, such as outside counsel fees and expenses, are charged to expense in the period incurred.

Employee Stock Purchase Plan, Stock Options and Warrants

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Employee Stock Purchase Plan Stock Options and Warrants

EMPLOYEE STOCK PURCHASE PLAN, STOCK OPTIONS AND WARRANTS.

Our stock-based compensation primarily consists of the following plans:

2018 Long-Term Incentive Plan. In June 2018, our Board of Directors adopted and our shareholders approved, the Merit Medical Systems, Inc. 2018 Long-Term Incentive Plan, which was subsequently amended effective December 14, 2018 (the “2018 Incentive Plan”) to supplement the Merit Medical Systems, Inc. 2006 Long-Term Incentive plan (the "2006 Incentive Plan"). The 2018 Incentive Plan provides for the granting of stock options, stock appreciation rights, restricted stock, stock units (including restricted stock units) and performance awards. Options may be granted to directors, officers, outside consultants and key employees and may be granted upon such terms and such conditions as the Compensation Committee of our Board of Directors determines. Options will typically vest on an annual basis over a three to five-year life with a contractual life of 7 years. As of December 31, 2018, a total of 2,900,000 shares remained available to be issued under the 2018 Incentive Plan.

2006 Long-Term Incentive Plan. In May 2006, our Board of Directors adopted and our shareholders approved, the 2006 Incentive Plan. As of December 31, 2018, the 2006 Incentive Plan was no longer being used for the granting of equity awards. However, as of December 31, 2018, options granted under this plan were still outstanding, vesting, and being exercised and will continue to be outstanding until the vesting periods end and the terms of the equity awards expire.

Employee Stock Purchase Plan. We have a non-qualified Employee Stock Purchase Plan (“ESPP”), which has an expiration date of June 30, 2026. As of December 31, 2018, the total number of shares of common stock that remained available to be issued under our non-qualified plan was 105,207 shares. ESPP participants purchase shares on a quarterly basis at a price equal to 95% of the market price of the common stock at the end of the applicable offering period.

Stock-Based Compensation Expense. The stock-based compensation expense before income tax expense for the years ended December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
Cost of goods sold	$	870	$	632	$	472
Research and development	553		376		184
Selling, general, and administrative	4,694		3,067		1,850
Stock-based compensation expense before taxes	$	6,117	$	4,075	$	2,506

We recognize stock-based compensation expense (net of a forfeiture rate) for those awards which are expected to vest on a straight-line basis over the requisite service period. We estimate the forfeiture rate based on our historical experience and expectations about future forfeitures. As of December 31, 2018, the total remaining unrecognized compensation cost related to non-vested stock options, net of expected forfeitures, was approximately $19.0 million and is expected to be recognized over a weighted average period of 3.09 years.

In applying the Black-Scholes methodology to the option grants, the fair value of our stock-based awards granted were estimated using the following assumptions for the periods indicated below:



	2018			2017			2016
Risk-free interest rate	2.63%	-	2.77%	1.77%	-	1.83%	1.15%	-	1.40%
Expected option life	5.0 years			5.0 years			5.0 years
Expected dividend yield	—%			—%			—%
Expected price volatility	34.06%	-	34.32%	33.81%	-	34.07%	34.28%	-	37.06%

The average risk-free interest rate is determined using the U.S. Treasury rate in effect as of the date of grant, based on the expected term of the stock option. We determine the expected term of the stock options using the historical exercise behavior of employees. The expected price volatility was determined using a weighted average of daily historical volatility of our stock price over the corresponding expected option life and implied volatility based on recent trends of the daily historical volatility. For options with a vesting period, compensation expense is recognized on a straight-line basis over the service period, which corresponds to the vesting period. During the years ended December 31, 2018, 2017 and 2016, approximately 692,000, 1.3 million and 880,000 stock-based compensation grants were made, respectively, for a total fair value of approximately $11.1 million, $12.4 million and $5.2 million, net of estimated forfeitures, respectively.

The table below presents information related to stock option activity for the years ended December 31, 2018, 2017 and 2016 (in thousands):



	2018		2017		2016
Total intrinsic value of stock options exercised	$	25,692	$	9,264	$	3,648
Cash received from stock option exercises	8,510		5,552		4,577
Excess tax benefit from the exercise of stock options	4,278		2,264		669

Changes in stock options for the year ended December 31, 2018, consisted of the following (shares and intrinsic value in thousands):



	Number of Shares		Weighted Average Exercise Price		Remaining Contractual Term (in years)	Intrinsic Value
Beginning balance	3,623		$	20.40
Granted	692		46.45
Exercised	(690	)	15.41
Forfeited/expired	(118	)	26.90
Outstanding at December 31	3,507		26.30		4.54	$	103,483
Exercisable	1,101		17.71		3.33	41,963
Ending vested and expected to vest	3,388		26.05		4.51	100,820

The weighted average grant-date fair value of options granted during the years ended December 31, 2018, 2017 and 2016 was $16.05, $9.57 and $5.94, respectively.

The following table summarizes information about stock options outstanding at December 31, 2018 (shares in thousands):



			Options Outstanding				Options Exercisable
Range of Exercise			Number Outstanding	Weighted Average Remaining Contractual Life (in years)	Weighted Average Exercise Price		Number Exercisable	Weighted Average Exercise Price
$9.95	-	$16.05	982	3.02	$	13.99	585	$	13.16
$16.41	-	$22.00	683	3.73	$	18.93	319	$	18.76
$28.20	-	$28.20	961	5.27	$	28.20	159	$	28.20
$34.40	-	$50.50	881	6.04	$	43.65	38	$	34.74
$9.95	-	$50.50	3,507				1,101

Segment Reporting and Foreign Operations

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Segment Reporting and Foreign Operations

SEGMENT REPORTING AND FOREIGN OPERATIONS

We report our operations in two operating segments: cardiovascular and endoscopy. Our cardiovascular segment consists of cardiology and radiology medical device products which assist in diagnosing and treating coronary artery disease, peripheral vascular disease and other non-vascular diseases and includes embolotherapeutic, cardiac rhythm management ("CRM"), electrophysiology ("EP"), critical care, Cianna Medical, interventional oncology and spine devices, and breast cancer localization and guidance. Our endoscopy segment consists of gastroenterology and pulmonology medical device products which assist in the palliative treatment of expanding esophageal, tracheobronchial and biliary strictures caused by malignant tumors. We evaluate the performance of our operating segments based on operating income (loss). See Note 2 for a detailed breakout of our sales by operating segment and product group, disaggregated between domestic and international sales.

During the years ended December 31, 2018, 2017 and 2016, we had international sales of approximately $386.3 million, $307.1 million and $233.5 million, respectively, or approximately 44%, 42% and 39%, respectively, of net sales, primarily in China, Japan, Germany, France, the United Kingdom and Russia. China represents our most significant international sales market with sales of approximately $92.7 million, $73.4 million, and $59.9 million for the years ended December 31, 2018, 2017 and 2016, respectively. International sales are attributed based on location of the customer receiving the product.

Our long-lived assets (which are comprised of our net property, plant and equipment) by geographic area at December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
United States	$	231,864	$	202,504	$	194,715
Ireland	45,283		45,671		47,337
Other foreign countries	54,305		44,645		34,521
Total	$	331,452	$	292,820	$	276,573

Financial information relating to our reportable operating segments and reconciliations to the consolidated totals for the years ended December 31, 2018, 2017 and 2016, are as follows (in thousands):



	2018			2017		2016
Net Sales
Cardiovascular	$	849,477		$	700,613	$	580,151
Endoscopy	33,276			27,239		23,687
Total net sales	882,753			727,852		603,838

Operating expenses
Cardiovascular	321,461			281,095		218,659
Endoscopy	14,692			12,089		11,490
Total operating expenses	336,153			293,184		230,149

Operating income
Cardiovascular	49,289			24,819		30,053
Endoscopy	9,328			8,250		4,823
Total operating income	58,617			33,069		34,876

Total other income (expense) - net	(9,098		)	2,812		(9,490		)
Income tax expense	7,502			8,358		5,265

Net income	$	42,017		$	27,523	$	20,121

Total assets by business segment at December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	1,588,970	$	1,103,806	$	932,927
Endoscopy	31,042		8,005		9,876
Total	$	1,620,012	$	1,111,811	$	942,803

Total depreciation and amortization by business segment for the years ended December 31, 2018, 2017, and 2016 consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	68,722	$	52,700	$	42,806
Endoscopy	824		882		949
Total	$	69,546	$	53,582	$	43,755

Total capital expenditures for property and equipment by business segment for the years ended December 31, 2018, 2017 and 2016 consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	63,032	$	38,437	$	32,613
Endoscopy	292		186		224
Total	$	63,324	$	38,623	$	32,837

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2018
Defined Contribution Plan [Abstract]
Employee Benefit Plans	EMPLOYEE BENEFIT PLANS We have a contributory 401(k) savings and profit sharing plan (the “Plan”) covering all U.S. full-time employees who are at least 18 years of age. The Plan has a 90-day minimum service requirement. We may contribute, at our discretion, matching contributions based on the employees’ compensation. Contributions we made to the Plan for the years ended December 31, 2018, 2017 and 2016, totaled approximately $3.5 million, $2.4 million and $2.3 million, respectively. We also have defined contribution plans covering some of our foreign employees. We contribute between 2% and 32% of the employee’s compensation for certain foreign non-management employees, and between 2% and 32% of the employee’s compensation for certain foreign management employees. Contributions made to these plans for the years ended December 31, 2018, 2017 and 2016, totaled approximately $3.0 million, $2.3 million and $1.1 million, respectively.

Quarterly Results of Operations (Unaudited)

12 Months Ended

Dec. 31, 2018

Quarterly Financial Information Disclosure [Abstract]

Quarterly Results of Operations (Unaudited)

QUARTERLY RESULTS OF OPERATIONS (UNAUDITED)

Quarterly data for the years ended December 31, 2018 and 2017 consisted of the following (in thousands, except per share amounts):



	Quarter Ended
	March 31		June 30		September 30			December 31
2018
Net sales	$	203,035	$	224,810	$	221,659		$	233,249
Gross profit	88,056		100,009		102,039			104,666
Income from operations	8,781		15,114		21,061			13,661
Income tax expense	1,090		624		2,766			3,022
Net income	5,269		10,941		16,619			9,188
Basic earnings per common share	0.10		0.22		0.31			0.17
Diluted earnings per common share	0.10		0.21		0.30			0.16


2017
Net sales	$	171,069	$	186,549	$	179,337		$	190,897
Gross profit	75,942		84,141		80,514			85,656
Income from operations	5,609		13,362		879			13,219
Income tax expense	690		1,830		1,364			4,474
Net income (loss)	14,803		9,483		(3,569		)	6,806
Basic earnings per common share	0.33		0.19		(0.07		)	0.14
Diluted earnings per common share	0.32		0.19		(0.07		)	0.13

Basic and diluted earnings per share are computed independently for each of the quarters presented. Therefore, the sum of the quarterly amounts may not equal the total computed for the year.

Fair Value Measurements

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Measurements

FAIR VALUE MEASUREMENTS

Our financial assets and (liabilities) carried at fair value measured on a recurring basis as of December 31, 2018 and 2017, consisted of the following (in thousands):



				Fair Value Measurements Using
	Total Fair			Quoted prices in		Significant other			Significant
	Value at			active markets		observable inputs			unobservable inputs
Description	December 31, 2018			(Level 1)		(Level 2)			(Level 3)

Interest rate contracts (1)	$	5,772		$	—	$	5,772		$	—
Foreign currency contract assets, current and long-term (2)	$	1,578		$	—	$	1,578		$	—
Foreign currency contract liabilities, current and long-term (3)	$	(1,608	)	$	—	$	(1,608	)	$	—

				Fair Value Measurements Using
	Total Fair			Quoted prices in		Significant other			Significant
	Value at			active markets		observable inputs			unobservable inputs
Description	December 31, 2017			(Level 1)		(Level 2)			(Level 3)

Interest rate contracts (1)	$	5,749		$	—	$	5,749		$	—
Foreign currency contract assets, current and long-term (2)	$	621		$	—	$	621		$	—
Foreign currency contract liabilities, current and long-term (3)	$	(1,391	)	$	—	$	(1,391	)	$	—

(1) The fair value of the interest rate contracts is determined using Level 2 fair value inputs and is recorded as other long-term assets or other long-term obligations in the consolidated balance sheets.

(2) The fair value of the foreign currency contract assets (including those designated as hedging instruments and those not designated as hedging instruments) is determined using Level 2 fair value inputs and is recorded as prepaid and other assets or other long-term assets in the consolidated balance sheets.

(3) The fair value of the foreign currency contract liabilities (including those designated as hedging instruments and those not designated as hedging instruments) is determined using Level 2 fair value inputs and is recorded as accrued expenses or other long-term obligations in the consolidated balance sheets.

Certain of our business combinations involve the potential for the payment of future contingent consideration, generally based on a percentage of future product sales or upon attaining specified future revenue milestones. See Note 3 for further information regarding these acquisitions. The contingent consideration liability is re-measured at the estimated fair value at each reporting period with the change in fair value recognized within operating expenses in the accompanying consolidated statements of income. We measure the initial liability and re-measure the liability on a recurring basis using Level 3 inputs as defined under authoritative guidance for fair value measurements. Changes in the fair value of our contingent consideration liability during the years ended December 31, 2018 and 2017, consisted of the following (in thousands):



	2018			2017
Beginning balance	$	10,956		$	683
Contingent consideration liability recorded as the result of acquisitions (see Note 3)	72,209			10,400
Fair value adjustments recorded to income during the period	(698		)	(66		)
Contingent payments made	(231		)	(61		)
Ending balance	$	82,236		$	10,956

As of December 31, 2018, approximately $58.5 million was included in other long-term obligations and approximately $23.8 million was included in accrued expenses in our consolidated balance sheet. As of December 31, 2017, approximately $10.7 million was included in other long-term obligations and $289,000 was included in accrued expenses in our consolidated balance sheet. The cash paid to settle the contingent consideration liability recognized at fair value as of the acquisition date (including measurement-period adjustments) has been reflected as a cash outflow from financing activities in the accompanying consolidated statements of cash flows.

During the year ended December 31, 2016, we sold an equity investment for cash and for the right to receive additional payments based on various contingent milestones. We determined the fair value of the contingent payments using Level 3 inputs defined under authoritative guidance for fair value measurements, and we recorded a contingent receivable asset, which as of

December 31, 2018 and 2017 had a value of approximately $607,000 and $760,000, respectively. We record any changes in fair value to operating expenses as part of our cardiovascular segment in our consolidated statements of income. For the year ended December 31, 2018, there were no significant changes to the fair value of the contingent receivable which impacted net income and we collected payments of approximately $153,000. During the year ended December 31, 2017, we recorded a gain on the contingent receivable of approximately $232,000. As of December 31, 2018, the receivable of approximately $607,000 was included in other receivables as a current asset in our consolidated balance sheet. As of December 31, 2017, approximately $319,000 was included in other long-term assets and approximately $441,000 was included in other receivables as a current asset in our consolidated balance sheet.

The recurring Level 3 measurement of our contingent consideration liability and contingent receivable includes the following significant unobservable inputs at December 31, 2018 and 2017 (amounts in thousands):



Contingent consideration asset or liability	Fair value at December 31, 2018		Valuation technique	Unobservable inputs	Range
Revenue-based royalty	$	10,661	Discounted cash flow	Discount rate	9.9% - 25%
payments contingent liability			Discounted cash flow	Projected year of payments	2018-2037

Supply chain milestone	$	13,593	Discounted cash flow	Discount rate	5.3%
contingent liability			Discounted cash flow	Probability of milestone payment	95%
				Projected year of payments	2019

Revenue milestones	$	57,982	Discounted cash flow	Discount rate	3.3% - 13%
contingent liability			Discounted cash flow	Projected year of payments	2019-2023

Contingent receivable	$	607	Discounted cash flow	Discount rate	10%
asset			Discounted cash flow	Probability of milestone payment	67%
				Projected year of payments	2019

Contingent consideration asset or liability	Fair value at December 31, 2017		Valuation technique	Unobservable inputs	Range
Revenue-based royalty	$	10,956	Discounted cash flow	Discount rate	9.9% - 15%
payments contingent liability			Discounted cash flow	Projected year of payments	2017-2037


Contingent receivable	$	760	Discounted cash flow	Discount rate	10%
asset			Discounted cash flow	Probability of milestone payment	75%
				Projected year of payments	2018-2019

The contingent consideration liability and contingent receivable are re-measured to fair value each reporting period using projected revenues, discount rates, probabilities of payment, and projected payment dates. Projected contingent payment amounts are discounted back to the current period using a discounted cash flow model. Projected revenues are based on our most recent internal operational budgets and long-range strategic plans. An increase (decrease) in either the discount rate or the time to payment, in isolation, may result in a significantly lower (higher) fair value measurement. A decrease in the probability of any milestone payment may result in lower fair value measurements. Our determination of the fair value of the contingent consideration liability and contingent receivable could change in future periods based upon our ongoing evaluation of these significant unobservable inputs. We intend to record any such change in fair value to operating expenses in our consolidated statements of income.

During the years ended December 31, 2018, 2017 and 2016, we had losses of approximately $814,000, $988,000 and $101,000, respectively, related to the measurement of non-financial assets at fair value on a nonrecurring basis subsequent to their initial recognition (see Note 5).

The carrying amount of cash and cash equivalents, receivables, and trade payables approximate fair value because of the immediate, short-term maturity of these financial instruments. The carrying amount of long-term debt approximates fair value, as determined by borrowing rates estimated to be available to us for debt with similar terms and conditions. The fair value of assets and liabilities whose carrying value approximates fair value is determined using Level 2 inputs, with the exception of cash and cash equivalents, which are Level 1 inputs.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Issuance of Common Stock	12 Months Ended
Issuance of Common Stock	Dec. 31, 2018
Equity [Abstract]
Issuance of Common Stock	ISSUANCE OF COMMON STOCK On July 30, 2018, we closed a public offering of 4,025,000 shares of common stock and received proceeds of approximately $205.0 million, which is net of approximately $12.0 million in underwriting discounts and commissions and approximately $366,000 in other direct cost incurred in connection with this equity offering. The net proceeds from the offering were used primarily to repay outstanding borrowings (principally revolving credit loans) under our Second Amended Credit Agreement. On March 28, 2017, we closed a public offering of 5,175,000 shares of common stock and received proceeds of approximately $136.6 million, which is net of approximately $8.8 million in underwriting discounts and commissions and approximately $816,000 in other direct costs incurred in connection with this equity offering. The net proceeds from the offering were used primarily to repay outstanding borrowings (including our term loan and revolving credit loans) under our Second Amended Credit Agreement.

Schedule II - Valuation and qualifying accounts

12 Months Ended

Dec. 31, 2018

SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]

Schedule II - Valuation and qualifying accounts

(2) Financial Statement Schedule.

— Schedule II - Valuation and qualifying accounts

Years Ended December 31, 2018, 2017 and 2016

(In thousands)



Description	Balance at Beginning of Year		Additions Charged to Costs and Expenses (a)		Deduction (b)	Balance at End of Year

ALLOWANCE FOR UNCOLLECTIBLE ACCOUNTS:

2016	(1,297	)	(612	)	322	(1,587	)
2017	(1,587	)	(1,012	)	830	(1,769	)
2018	(1,769	)	(1,055	)	469	(2,355	)

(a) We record a bad debt provision based upon historical experience and a review of individual customer balances.

(b) When an individual customer balance becomes impaired and is deemed uncollectible, a deduction is made against the allowance for uncollectible accounts.

Years Ended December 31, 2018, 2017 and 2016

(In thousands)



Description	Balance at Beginning of Year		Additions Charged to Costs and Expenses (c)		Deduction	Balance at End of Year

TAX VALUATION ALLOWANCE:

2016	(1,981	)	(1,805	)	—	(3,786	)
2017	(3,786	)	(636	)	—	(4,422	)
2018	(4,422	)	(567	)	—	(4,989	)

(c) We record a valuation allowance against a deferred tax asset when it is determined that it is more likely than not that the deferred tax asset will not be realized.

Organization and Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Use of Estimates in Preparing Financial Statements

Principles of Consolidation

Principles of Consolidation. The consolidated financial statements include our wholly owned subsidiaries. Intercompany balances and transactions have been eliminated.

Cash and Cash Equivalents

Cash and Cash Equivalents. For purposes of the statements of cash flows, we consider interest bearing deposits with an original maturity date of three months or less to be cash equivalents.

Receivables

Inventories

Goodwill and Intangible Assets

Long-Lived Assets

Property and Equipment



Buildings	40 years
Manufacturing equipment	4	-	20 years
Furniture and fixtures	3	-	20 years
Land improvements	10	-	20 years
Leasehold improvements	4	-	25 years

Deferred Compensation

Other Assets

Deferred Credits

Revenue Recognition/Shipping and Handling/Cost of Sales

Research and Development

Research and Development. Research and development costs are expensed as incurred.

Income Taxes

Earnings per Common Share

Fair Value Measurements

Level 1: Quoted market prices in active markets for identical assets or liabilities.

Level 2: Observable market-based inputs or inputs that are corroborated by market data.

Level 3: Unobservable inputs that are not corroborated by market data.

Stock-Based Compensation

Concentration of Credit Risk

Foreign Currency

Derivatives

Derivatives. We use forward contracts to mitigate our exposure to volatility in foreign exchange rates, and we use interest rate swaps to hedge changes in the benchmark interest rate related to our Second Amended Credit Agreement described in Note 8. All derivatives are recognized in the consolidated balance sheets at fair value. Classification of each hedging instrument is based upon whether the maturity of the instrument is less than or greater than 12 months. We do not purchase or hold derivative financial instruments for speculative or trading purposes (see Note 9).Foreign Currency Risk. We operate on a global basis and are exposed to the risk that our financial condition, results of operations, and cash flows could be adversely affected by changes in foreign currency exchange rates. To reduce the potential effects of foreign currency exchange rate movements on net earnings, we enter into derivative financial instruments in the form of foreign currency exchange forward contracts with major financial institutions. Our policy is to enter into foreign currency derivative contracts with maturities of up to two years. We are primarily exposed to foreign currency exchange rate risk with respect to transactions and balances denominated in Euros, British Pounds, Chinese Renminbi, Mexican Pesos, Brazilian Reals, Australian Dollars, Hong Kong Dollars, Swiss Francs, Swedish Krona, Canadian Dollars, Danish Krone, Japanese Yen, Korea Won, and Singapore Dollars, among others. We do not use derivative financial instruments for trading or speculative purposes. We are not subject to any credit risk contingent features related to our derivative contracts, and counterparty risk is managed by allocating derivative contracts among several major financial institutions.

Derivatives Designated as Cash Flow Hedges

New Financial Accounting Standards

New Financial Accounting Standards.

Recently Adopted

Not Yet Adopted

All other issued and not yet effective accounting standards are not relevant to our financial statements.

Revenues (Tables)

12 Months Ended

Dec. 31, 2018

Revenue from Contract with Customer [Abstract]

Schedule of Disaggregation of Revenue

The following table presents sales by operating segment disaggregated based on type of product and geographic region for the years ended December 31, 2018, 2017 and 2016.



	Year Ended December 31, 2018						Year Ended December 31, 2017						Year Ended December 31, 2016
	United States		International		Total		United States		International		Total		United States		International		Total
Cardiovascular
Stand-alone devices	$	202,129	$	159,484	$	361,613	$	148,620	$	126,836	$	275,456	$	105,250	$	85,877	$	191,127
Cianna Medical	6,292		—		6,292		—		—		—		—		—		—
Custom kits and procedure trays	92,975		41,781		134,756		92,474		33,615		126,089		93,109		26,138		119,247
Inflation devices	31,717		60,702		92,419		31,848		48,027		79,875		35,506		38,410		73,916
Catheters	68,708		86,817		155,525		62,284		65,463		127,747		56,899		56,468		113,367
Embolization devices	20,433		29,605		50,038		22,374		27,158		49,532		24,075		21,960		46,035
CRM/EP	41,970		6,864		48,834		36,746		5,168		41,914		32,561		3,898		36,459
Total	464,224		385,253		849,477		394,346		306,267		700,613		347,400		232,751		580,151

Endoscopy
Endoscopy devices	32,189		1,087		33,276		26,357		882		27,239		22,950		737		23,687

Total	$	496,413	$	386,340	$	882,753	$	420,703	$	307,149	$	727,852	$	370,350	$	233,488	$	603,838

Acquisitions (Tables)

12 Months Ended

Dec. 31, 2018

Business Combinations [Abstract]

Schedule of Recognized Identified Assets Acquired and Liabilities Assumed

The purchase price was allocated as follows (in thousands):



Assets Acquired
Trade receivables	$	958
Inventories	2,157
Prepaid expenses and other assets	85
Property and equipment	1,472
Intangibles
Developed technology	21,100
Customer lists	700
Trademarks	2,900
Goodwill	8,989
Total assets acquired	38,361

Liabilities Assumed
Trade payables	(338		)
Accrued expenses	(23		)
Total liabilities assumed	(361		)

Net assets acquired	$	38,000

The purchase price was preliminarily allocated as follows (in thousands):



Inventories	$	1,308
Intangibles
Developed technology	32,830
Customer list	840
Trademarks	1,410
Goodwill	21,832

Total assets acquired	$	58,220

The following table summarizes the purchase price allocated to the net tangible and intangible assets acquired and liabilities assumed (in thousands):



	Assets Acquired
	Cash and cash equivalents	$	1,436
	Trade receivables	8,351
	Inventories	11,222
	Prepaid expenses and other assets	1,275
	Income tax refund receivable	165
	Property and equipment	2,319
	Deferred tax assets	202
	Intangibles
	Developed technology	2,200
	Customer lists	1,500
	Trademarks	900
	Total assets acquired	29,570

	Liabilities Assumed
	Trade payables	(2,414		)
	Accrued expenses	(5,083		)
	Income taxes payable	—
	Deferred income tax liabilities	(934		)
	Total liabilities assumed	(8,431		)

	Total net assets acquired	21,139
	Gain on bargain purchase ⁽¹⁾	(11,039		)
	Total purchase price	$	10,100

(1)	The total fair value of the net assets acquired from Argon exceeded the purchase price, resulting in a gain on bargain purchase which was recorded within other income (expense) in our consolidated statements of income. We believe the reason for the gain on bargain purchase was a result of the divestiture of a non-strategic, slow-growth critical care business for Argon. It is our understanding that the divestiture allows Argon to focus on its higher growth interventional portfolio.

The following table summarizes the aggregate purchase price (including contingent royalty payment liabilities) allocated to the assets acquired from Laurane (in thousands):



Inventories	$	594
Intangibles
Developed technology	14,920
Customer list	120
Goodwill	6,366

Total net assets acquired	$	22,000

The purchase price was allocated to the net tangible and intangible assets acquired and liabilities assumed, based on estimated fair values, as follows (in thousands):



Assets Acquired
Trade receivables	$	4,054
Other receivables	6
Inventories	8,585
Prepaid expenses	630
Property and equipment	1,630
Other long-term assets	145
Intangibles
Developed technology	67,600
Customer lists	2,400
Trademarks	4,400
Goodwill	24,818
Total assets acquired	114,268

Liabilities Assumed
Trade payables	(1,790		)
Accrued expenses	(5,298		)
Deferred income tax liabilities - current	(701		)
Deferred income tax liabilities - noncurrent	(10,844		)
Total liabilities assumed	(18,633		)

Net assets acquired, net of cash received of $1,327	$	95,635

The purchase price was preliminarily allocated as follows (in thousands):



Inventories	$	971
Intangibles
Developed technology	4,840
Customer list	120
Trademarks	400
Goodwill	938

Total assets acquired	$	7,269

The following table summarizes the aggregate purchase price allocated to the assets acquired from ITL (in thousands):



Assets Acquired
Trade receivables	$	1,287
Other receivables	56
Inventories	1,808
Prepaid expenses and other assets	65
Property and equipment	1,053
Intangibles
Customer lists	5,940
Goodwill	3,945
Total assets acquired	14,154

Liabilities Assumed
Trade payables	(216		)
Accrued expenses	(747		)
Deferred tax liabilities	(1,901		)
Total liabilities assumed	(2,864		)

Total net assets acquired	$	11,290

The purchase price was allocated as follows (in thousands):



Assets Acquired
Inventories	$	2,455
Property and equipment	290
Intangibles
Developed technology	12,100
Trademarks	700
Customers Lists	400
Goodwill	2,555

Total assets acquired	$	18,500

The following table summarizes the purchase price allocated to the assets acquired from BD (in thousands):



Inventories	$	5,804
Property and equipment	748
Intangibles
Developed technology	74,000
Customer list	4,200
Trademarks	4,900
In-process technology	2,500
Goodwill	9,728

Total assets acquired	$	101,880

The following table summarizes the purchase price allocated to the net assets acquired and liabilities assumed (in thousands):



Intangibles
Developed technology	$	7,800
In-process technology	920
Goodwill	4,281
Deferred tax liabilities	(3,101		)

Total net assets acquired	$	9,900

The following table summarizes the purchase price allocated to the assets acquired (in thousands):



Inventories	$	979
Property and equipment	58
Intangibles
Developed technology	5,400
Customer list	200
Goodwill	203

Total net assets acquired	$	6,840

The following table summarizes the preliminary purchase price allocated to the net assets acquired from Cianna Medical (in thousands):



Assets Acquired
Trade receivables	$	6,151
Inventories	5,803
Prepaid expenses and other assets	315
Property and equipment	1,047
Other long-term assets	14
Intangibles
Developed technology	134,510
Customer lists	3,330
Trademarks	7,080
Goodwill	65,885
Total assets acquired	224,135

Liabilities Assumed
Trade payables	(1,497		)
Accrued expenses	(2,384		)
Other long-term liabilities	(1,527		)
Deferred tax liabilities	(30,363		)
Total liabilities assumed	(35,771		)

Total net assets acquired	$	188,364

Business Acquisition, Pro Forma Information



	2018				2017					2016
	As Reported		Pro Forma		As Reported		Pro Forma			As Reported		Pro Forma
Net sales	$	882,753	$	928,336	$	727,852	$	768,571		$	603,838	$	664,366
Net income (loss)	42,017		20,699		27,523		(13,720		)	20,121		23,054
Earnings per common share:
Basic	$	0.80	$	0.40	$	0.56	$	(0.28	)	$	0.45	$	0.52
Diluted	$	0.78	$	0.38	$	0.55	$	(0.27	)	$	0.45	$	0.51

Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2018

Goodwill and Intangible Assets Disclosure [Abstract]

Changes in carrying amount of goodwill

The changes in the carrying amount of goodwill for the years ended December 31, 2018 and 2017, are as follows (in thousands):



	2018			2017
Goodwill balance at January 1	$	238,147		$	211,927
Effect of foreign exchange	(1,304		)	2,641
Additions as the result of acquisitions	98,590			23,579
Goodwill balance at December 31	$	335,433		$	238,147

Other intangible assets

Other intangible assets at December 31, 2018 and 2017, consisted of the following (in thousands):



	2018
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Patents	$	19,378	$	(5,012	)	$	14,366
Distribution agreements	8,012		(5,766		)	2,246
License agreements	26,930		(7,411		)	19,519
Trademarks	29,998		(6,586		)	23,412
Covenants not to compete	1,028		(1,000		)	28
Customer lists	39,936		(23,361		)	16,575
In-process technology	3,420		—			3,420

Total	$	128,702	$	(49,136	)	$	79,566



	2017
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Patents	$	16,528	$	(3,737	)	$	12,791
Distribution agreements	7,262		(4,686		)	2,576
License agreements	23,783		(5,568		)	18,215
Trademarks	16,224		(4,686		)	11,538
Covenants not to compete	1,028		(968		)	60
Customer lists	31,935		(18,482		)	13,453
In-process technology	920		—			920

Total	$	97,680	$	(38,127	)	$	59,553

Estimated amortization expense

Estimated amortization expense for the developed technology and other intangible assets for the next five years consists of the following as of December 31, 2018 (in thousands):



Year Ending December 31
2019	$	58,035
2020	55,341
2021	48,084
2022	46,648
2023	45,417

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Schedule of Income before Income Tax, Domestic and Foreign

For the years ended December 31, 2018, 2017 and 2016, income before income taxes is broken out between U.S. and foreign-sourced operations and consisted of the following (in thousands):



	2018		2017		2016
Domestic	$	21,084	$	14,531	$	6,174
Foreign	28,435		21,350		19,212
Total	$	49,519	$	35,881	$	25,386

Schedule of Components of Income Tax Expense (Benefit)

The components of the provision for income taxes for the years ended December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018			2017			2016
Current expense (benefit):
Federal	$	(1,132	)	$	3,849		$	1,933
State	582			645			492
Foreign	6,000			5,168			3,802
Total current expense	5,450			9,662			6,227

Deferred expense (benefit):
Federal	4,400			(314		)	(144		)
State	(667		)	(216		)	(195		)
Foreign	(1,681		)	(774		)	(623		)
Total deferred (benefit) expense	2,052			(1,304		)	(962		)

Total income tax expense	$	7,502		$	8,358		$	5,265

Schedule of Effective Income Tax Rate Reconciliation



	2018			2017			2016
Computed federal income tax expense at applicable statutory rate	$	10,399		$	12,559		$	8,885
State income taxes	(59		)	279			193
Tax credits	(1,734		)	(1,377		)	(1,164		)
Production activity deduction	—			—			(53		)
Foreign tax rate differential	(1,361		)	(3,329		)	(3,717		)
Uncertain tax positions	267			(19		)	597
Deferred compensation insurance assets	186			(479		)	(307		)
Transaction-related expenses	223			90			274
U.S. transition tax	(3,271		)	10,612			—
TCJA remeasurement of deferred taxes	(71		)	(8,383		)	—
Stock-based payments	(4,278		)	(2,264		)	—
Bargain purchase gain	—			(1,570		)	—
In-process research and development	—			1,486			—
Net GILTI	347			—			—
Foreign withholding tax	5,590			—			—
Other — including the effect of graduated rates	1,264			753			557
Total income tax expense	$	7,502		$	8,358		$	5,265

Schedule of Deferred Tax Assets and Liabilities

Deferred income tax assets and liabilities at December 31, 2018 and 2017, consisted of the following temporary differences and carry-forward items (in thousands):



	2018			2017
Deferred income tax assets:
Allowance for uncollectible accounts receivable	$	606		$	467
Accrued compensation expense	7,414			5,154
Inventory differences	1,269			2,505
Net operating loss carryforwards	20,226			15,741
Deferred revenue	46			58
Stock-based compensation expense	2,833			2,281
Other	9,243			8,986
Total deferred income tax assets	41,637			35,192

Deferred income tax liabilities:
Prepaid expenses	(1,142		)	(930		)
Property and equipment	(20,045		)	(20,352		)
Intangible assets	(58,883		)	(28,588		)
Foreign withholding tax	(5,590		)	—
Other	(4,350		)	(1,830		)
Total deferred income tax liabilities	(90,010		)	(51,700		)
Valuation allowance	(4,989		)	(4,422		)
Net deferred income tax assets (liabilities)	$	(53,362	)	$	(20,930	)

Reported as:
Deferred income tax assets - Long-term	$	3,001		$	2,359
Deferred income tax liabilities - Long-term	(56,363		)	(23,289		)
Net deferred income tax liabilities	$	(53,362	)	$	(20,930	)

Summary of Income Tax Contingencies



Tabular Roll-forward	2018			2017			2016

Unrecognized tax benefits, opening balance	$	2,749		$	2,549		$	1,982
Gross increases in tax positions taken in a prior year	35			80			77
Gross increases in tax positions taken in the current year	586			403			856
Lapse of applicable statute of limitations	(423		)	(283		)	(366		)
Unrecognized tax benefits, ending balance	$	2,947		$	2,749		$	2,549

Revolving Credit Facility and Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2018

Debt Disclosure [Abstract]

Schedule of Long-term Debt Instruments

Principal balances outstanding under our long-term debt obligations as of December 31, 2018 and 2017, consisted of the following (in thousands):



	2018			2017
2016 Term loan	$	72,500		$	85,000
2016 Revolving credit loans	316,000			187,000
Collateralized debt facility	7,000			6,959
Less unamortized debt issuance costs	(348		)	(487		)
Total long-term debt	395,152			278,472
Less current portion	22,000			19,459
Long-term portion	$	373,152		$	259,013

Schedule of Long-term Debt Covenants

The Second Amended Credit Agreement requires that we maintain certain financial covenants, as follows:



		Covenant Requirement
Consolidated Total Leverage Ratio (1)
	January 1, 2018 and thereafter	3.5 to 1.0
Consolidated EBITDA (2)		1.25 to 1.0
Consolidated Net Income (3)		$—
Facility Capital Expenditures (4)		$30 million

(1)	Maximum Consolidated Total Leverage Ratio (as defined in the Second Amended Credit Agreement) as of any fiscal quarter end.
(2)	Minimum ratio of Consolidated EBITDA (as defined in the Second Amended Credit Agreement and adjusted for certain expenditures) to Consolidated Fixed Charges (as defined in the Second Amended Credit Agreement) for any period of four consecutive fiscal quarters.
(3)	Minimum level of Consolidated Net Income (as defined in the Second Amended Credit Agreement) for certain periods, and subject to certain adjustments.
(4)	Maximum level of the aggregate amount of all Facility Capital Expenditures (as defined in the Second Amended Credit Agreement) in any fiscal year.

Schedule of Maturities of Long-term Debt

Future minimum principal payments on our long-term debt as of December 31, 2018, are as follows (in thousands):



Years Ending	Future Minimum
December 31	Principal Payments
2019	22,000
2020	17,500
2021	356,000
Total future minimum principal payments	$	395,500

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21506-112644

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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+ Details

Derivatives (Tables)

12 Months Ended

Dec. 31, 2018

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions



Currency	Symbol	Forward Notional Amount
Australian Dollar	AUD	11,400
Brazilian Real	BRL	9,000
Canadian Dollar	CAD	2,300
Swiss Franc	CHF	269
Chinese Renminbi	CNY	63,200
Danish Krone	DKK	3,237
Euro	EUR	5,927
British Pound	GBP	2,358
Hong Kong Dollar	HKD	11,000
Japanese Yen	JPY	265,000
Korean Won	KRW	5,500,000
Mexican Peso	MXN	23,000
Swedish Krona	SEK	9,627
Singapore Dollar	SGD	8,500



Currency	Symbol	Forward Notional Amount
Australian Dollar	AUD	3,000
Canadian Dollar	CAD	4,410
Swiss Franc	CHF	2,145
Chinese Renminbi	CNY	160,000
Danish Krone	DKK	17,225
Euro	EUR	20,310
British Pound	GBP	5,280
Japanese Yen	JPY	1,145,000
Korean Won	KRW	3,050,000
Mexican Peso	MXN	230,000
Swedish Krona	SEK	30,210

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value

The fair value of derivative instruments on a gross basis is as follows (in thousands):



		Fair Value
	Balance Sheet Location	December 31, 2018			December 31, 2017
Derivatives designated as hedging instruments
Assets
Interest rates swaps	Other assets (long-term)	$	5,772		$	5,749
Foreign currency forward contracts	Prepaid expenses and other assets	613			363
Foreign currency forward contracts	Other assets (long-term)	151			35

Liabilities
Foreign currency forward contracts	Accrued expenses	(711		)	(468		)
Foreign currency forward contracts	Other long-term obligations	(101		)	(82		)

Derivatives not designated as hedging instruments
Assets
Foreign currency forward contracts	Prepaid expenses and other assets	$	814		$	223
Liabilities
Foreign currency forward contracts	Accrued expenses	(796		)	(841		)

Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss)



	Amount of Gain/(Loss) recognized in OCI							Amount of Gain/(Loss) reclassified from AOCI
	Year ended December 31,							Year ended December 31,
	2018	2017		2016				2018	2017		2016
Derivative instrument							Location in statements of income
Interest rate swaps	$1,559	$	853	$	4,989		Interest Expense	$1,537	95		(718	)
Foreign currency forward contracts	539	491		(205		)	Revenue	136	(277	)	21
							Cost of goods sold	361	625		(26	)

Derivative Instruments, Gain (Loss)

The following gains/(losses) from these derivative instruments were recognized in our consolidated statements of income for the years presented (in thousands):



		Year ended December 31,
		2018		2017			2016
Derivative Instrument	Location in statements of income
Foreign currency forward contracts	Other expense	$	4,147	$	(4,746	)	$	69

Employee Stock Purchase Plan, Stock Options and Warrants (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

The stock-based compensation expense before income tax expense for the years ended December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
Cost of goods sold	$	870	$	632	$	472
Research and development	553		376		184
Selling, general, and administrative	4,694		3,067		1,850
Stock-based compensation expense before taxes	$	6,117	$	4,075	$	2,506

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

In applying the Black-Scholes methodology to the option grants, the fair value of our stock-based awards granted were estimated using the following assumptions for the periods indicated below:



	2018			2017			2016
Risk-free interest rate	2.63%	-	2.77%	1.77%	-	1.83%	1.15%	-	1.40%
Expected option life	5.0 years			5.0 years			5.0 years
Expected dividend yield	—%			—%			—%
Expected price volatility	34.06%	-	34.32%	33.81%	-	34.07%	34.28%	-	37.06%

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding and Exercisable

The table below presents information related to stock option activity for the years ended December 31, 2018, 2017 and 2016 (in thousands):



	2018		2017		2016
Total intrinsic value of stock options exercised	$	25,692	$	9,264	$	3,648
Cash received from stock option exercises	8,510		5,552		4,577
Excess tax benefit from the exercise of stock options	4,278		2,264		669

Schedule of Share-based Compensation, Stock Options, Activity

Changes in stock options for the year ended December 31, 2018, consisted of the following (shares and intrinsic value in thousands):



	Number of Shares		Weighted Average Exercise Price		Remaining Contractual Term (in years)	Intrinsic Value
Beginning balance	3,623		$	20.40
Granted	692		46.45
Exercised	(690	)	15.41
Forfeited/expired	(118	)	26.90
Outstanding at December 31	3,507		26.30		4.54	$	103,483
Exercisable	1,101		17.71		3.33	41,963
Ending vested and expected to vest	3,388		26.05		4.51	100,820

Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range

The following table summarizes information about stock options outstanding at December 31, 2018 (shares in thousands):



			Options Outstanding				Options Exercisable
Range of Exercise			Number Outstanding	Weighted Average Remaining Contractual Life (in years)	Weighted Average Exercise Price		Number Exercisable	Weighted Average Exercise Price
$9.95	-	$16.05	982	3.02	$	13.99	585	$	13.16
$16.41	-	$22.00	683	3.73	$	18.93	319	$	18.76
$28.20	-	$28.20	961	5.27	$	28.20	159	$	28.20
$34.40	-	$50.50	881	6.04	$	43.65	38	$	34.74
$9.95	-	$50.50	3,507				1,101

Segment Reporting and Foreign Operations (Tables)

12 Months Ended

Dec. 31, 2018

Segment Reporting [Abstract]

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas

Our long-lived assets (which are comprised of our net property, plant and equipment) by geographic area at December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
United States	$	231,864	$	202,504	$	194,715
Ireland	45,283		45,671		47,337
Other foreign countries	54,305		44,645		34,521
Total	$	331,452	$	292,820	$	276,573

Schedule of Segment Reporting Information, by Segment

Total depreciation and amortization by business segment for the years ended December 31, 2018, 2017, and 2016 consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	68,722	$	52,700	$	42,806
Endoscopy	824		882		949
Total	$	69,546	$	53,582	$	43,755

Total capital expenditures for property and equipment by business segment for the years ended December 31, 2018, 2017 and 2016 consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	63,032	$	38,437	$	32,613
Endoscopy	292		186		224
Total	$	63,324	$	38,623	$	32,837

Financial information relating to our reportable operating segments and reconciliations to the consolidated totals for the years ended December 31, 2018, 2017 and 2016, are as follows (in thousands):



	2018			2017		2016
Net Sales
Cardiovascular	$	849,477		$	700,613	$	580,151
Endoscopy	33,276			27,239		23,687
Total net sales	882,753			727,852		603,838

Operating expenses
Cardiovascular	321,461			281,095		218,659
Endoscopy	14,692			12,089		11,490
Total operating expenses	336,153			293,184		230,149

Operating income
Cardiovascular	49,289			24,819		30,053
Endoscopy	9,328			8,250		4,823
Total operating income	58,617			33,069		34,876

Total other income (expense) - net	(9,098		)	2,812		(9,490		)
Income tax expense	7,502			8,358		5,265

Net income	$	42,017		$	27,523	$	20,121

Reconciliation of Assets from Segment to Consolidated

Total assets by business segment at December 31, 2018, 2017 and 2016, consisted of the following (in thousands):



	2018		2017		2016
Cardiovascular	$	1,588,970	$	1,103,806	$	932,927
Endoscopy	31,042		8,005		9,876
Total	$	1,620,012	$	1,111,811	$	942,803

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

Our financial assets and (liabilities) carried at fair value measured on a recurring basis as of December 31, 2018 and 2017, consisted of the following (in thousands):



				Fair Value Measurements Using
	Total Fair			Quoted prices in		Significant other			Significant
	Value at			active markets		observable inputs			unobservable inputs
Description	December 31, 2018			(Level 1)		(Level 2)			(Level 3)

Interest rate contracts (1)	$	5,772		$	—	$	5,772		$	—
Foreign currency contract assets, current and long-term (2)	$	1,578		$	—	$	1,578		$	—
Foreign currency contract liabilities, current and long-term (3)	$	(1,608	)	$	—	$	(1,608	)	$	—

				Fair Value Measurements Using
	Total Fair			Quoted prices in		Significant other			Significant
	Value at			active markets		observable inputs			unobservable inputs
Description	December 31, 2017			(Level 1)		(Level 2)			(Level 3)

Interest rate contracts (1)	$	5,749		$	—	$	5,749		$	—
Foreign currency contract assets, current and long-term (2)	$	621		$	—	$	621		$	—
Foreign currency contract liabilities, current and long-term (3)	$	(1,391	)	$	—	$	(1,391	)	$	—

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation

Changes in the fair value of our contingent consideration liability during the years ended December 31, 2018 and 2017, consisted of the following (in thousands):



	2018			2017
Beginning balance	$	10,956		$	683
Contingent consideration liability recorded as the result of acquisitions (see Note 3)	72,209			10,400
Fair value adjustments recorded to income during the period	(698		)	(66		)
Contingent payments made	(231		)	(61		)
Ending balance	$	82,236		$	10,956

Fair Value Inputs, Liabilities, Quantitative Information



Contingent consideration asset or liability	Fair value at December 31, 2018		Valuation technique	Unobservable inputs	Range
Revenue-based royalty	$	10,661	Discounted cash flow	Discount rate	9.9% - 25%
payments contingent liability			Discounted cash flow	Projected year of payments	2018-2037

Supply chain milestone	$	13,593	Discounted cash flow	Discount rate	5.3%
contingent liability			Discounted cash flow	Probability of milestone payment	95%
				Projected year of payments	2019

Revenue milestones	$	57,982	Discounted cash flow	Discount rate	3.3% - 13%
contingent liability			Discounted cash flow	Projected year of payments	2019-2023

Contingent receivable	$	607	Discounted cash flow	Discount rate	10%
asset			Discounted cash flow	Probability of milestone payment	67%
				Projected year of payments	2019

Contingent consideration asset or liability	Fair value at December 31, 2017		Valuation technique	Unobservable inputs	Range
Revenue-based royalty	$	10,956	Discounted cash flow	Discount rate	9.9% - 15%
payments contingent liability			Discounted cash flow	Projected year of payments	2017-2037


Contingent receivable	$	760	Discounted cash flow	Discount rate	10%
asset			Discounted cash flow	Probability of milestone payment	75%
				Projected year of payments	2018-2019

Organization and Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Depreciation	$ 28.3	$ 26.8	$ 24.5
Buildings
Property, Plant and Equipment [Line Items]
Useful life	40 years
Minimum \| Manufacturing equipment
Property, Plant and Equipment [Line Items]
Useful life	4 years
Minimum \| Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	3 years
Minimum \| Land improvements
Property, Plant and Equipment [Line Items]
Useful life	10 years
Minimum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Useful life	4 years
Maximum \| Manufacturing equipment
Property, Plant and Equipment [Line Items]
Useful life	20 years
Maximum \| Furniture and fixtures
Property, Plant and Equipment [Line Items]
Useful life	20 years
Maximum \| Land improvements
Property, Plant and Equipment [Line Items]
Useful life	20 years
Maximum \| Leasehold improvements
Property, Plant and Equipment [Line Items]
Useful life	25 years

Organization and Summary of Significant Accounting Policies - Concentration of Credit Risk (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Customer concentration risk \| Sales \| One Customer
Product Information [Line Items]
Concentration for largest customer	2.00%	2.00%	3.00%

Organization and Summary of Significant Accounting Policies - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accumulated other comprehensive income (loss), interest rate swaps, net of tax	$ (3,500)	$ 3,500
Accumulated other comprehensive income (loss), interest rate swap, tax benefit	(2,200)	(2,200)
Accumulated other comprehensive income (loss) related to foreign currency translation, net of tax	(5,600)	(1,900)
Accumulated other comprehensive income (loss), foreign currency translation, tax benefit	$ (9)	$ 0

Organization and Summary of Significant Accounting Policies - New Financial Accounting Standards (Details) - Accounting Standards Update 2016-02 - Pro Forma $ in Millions	Dec. 31, 2018 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating right-of-use assets	$ 80
Lease liabilities	$ 80

Revenues - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net Sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
United States
Disaggregation of Revenue [Line Items]
Net Sales									496,413	420,703	370,350
International
Disaggregation of Revenue [Line Items]
Net Sales									386,340	307,149	233,488
Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									849,477	700,613	580,151
Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									464,224	394,346	347,400
Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									385,253	306,267	232,751
Endoscopy
Disaggregation of Revenue [Line Items]
Net Sales									33,276	27,239	23,687
Stand-alone devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									361,613	275,456	191,127
Stand-alone devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									202,129	148,620	105,250
Stand-alone devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									159,484	126,836	85,877
Cianna Medical \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									6,292	0	0
Cianna Medical \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									6,292	0	0
Cianna Medical \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									0	0	0
Custom kits and procedure trays \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									134,756	126,089	119,247
Custom kits and procedure trays \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									92,975	92,474	93,109
Custom kits and procedure trays \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									41,781	33,615	26,138
Inflation devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									92,419	79,875	73,916
Inflation devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									31,717	31,848	35,506
Inflation devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									60,702	48,027	38,410
Catheters \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									155,525	127,747	113,367
Catheters \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									68,708	62,284	56,899
Catheters \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									86,817	65,463	56,468
Embolization devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									50,038	49,532	46,035
Embolization devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									20,433	22,374	24,075
Embolization devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									29,605	27,158	21,960
CRM/EP \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									48,834	41,914	36,459
CRM/EP \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									41,970	36,746	32,561
CRM/EP \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									6,864	5,168	3,898
Endoscopy devices \| Endoscopy
Disaggregation of Revenue [Line Items]
Net Sales									33,276	27,239	23,687
Endoscopy devices \| Endoscopy \| United States
Disaggregation of Revenue [Line Items]
Net Sales									32,189	26,357	22,950
Endoscopy devices \| Endoscopy \| International
Disaggregation of Revenue [Line Items]
Net Sales									$ 1,087	$ 882	$ 737

Acquisitions - Narrative (Details) $ in Millions																					1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
Acquisitions - Narrative (Details) $ in Millions	Dec. 14, 2018 USD ($)	Nov. 13, 2018 USD ($)	Jul. 31, 2018 USD ($) shares	May 23, 2018 USD ($)	May 18, 2018 USD ($)	Apr. 06, 2018 USD ($)	Feb. 14, 2018 USD ($)	Oct. 02, 2017 USD ($)	Sep. 01, 2017	Aug. 04, 2017 USD ($)	Jul. 03, 2017 USD ($)	Jul. 01, 2017 USD ($)	Jun. 16, 2017 USD ($)	May 23, 2017 USD ($) shares	May 19, 2017 USD ($)	May 01, 2017 USD ($)	Jan. 31, 2017 USD ($) patent	Dec. 19, 2016 USD ($) shares	Jul. 06, 2016 USD ($)	Feb. 04, 2016 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares	Sep. 30, 2017 AUD ($)
Business Acquisition [Line Items]
Payments to acquire intangible assets																								$ 3,012,000	$ 2,577,000	$ 2,217,000
Loan for long-term agreement																								10,750,000	0	0
QX Medical, LLC
Business Acquisition [Line Items]
Payments to acquire intangible assets					$ 750,000
NinePoint Medical, Inc.
Business Acquisition [Line Items]
Net sales related to acquisition																							$ 3,000,000.0
Option to purchase outstanding equity, up to						100.00%
Consideration received, option to purchase remaining equity						$ 10,000,000
Loan for long-term agreement						$ 10,500,000
Interest rate on loan						9.00%
Fusion Medical, Inc.
Business Acquisition [Line Items]
Ownership interest (percent)														19.50%
Total purchase price														$ 2,500,000
Equity method investment														$ 2,500,000
Fusion Medical, Inc. \| Preferred Stock
Business Acquisition [Line Items]
Shares acquired (in shares) \| shares														182,000
Sugan Co, Ltd.
Business Acquisition [Line Items]
Term of right to manufacture and sell certain products															4 years
Bluegrass Vascular Technologies, Inc. \| Investee
Business Acquisition [Line Items]
Payments to acquire investment																		$ 5,000,000.0
Number of units acquired \| shares																		1,251,878
Percent owned																		19.50%
Cost method investment																		$ 4,000,000.0
Cagent Vascular, LLC \| Limited Liability Company
Business Acquisition [Line Items]
Payments to acquire investment																									$ 3,000,000	$ 3,000,000.0
Number of units acquired \| shares																						3,000,000			3,000,000	3,000,000
Developed technology
Business Acquisition [Line Items]
Intangible assets																							383,147,000	383,147,000	$ 167,771,000
Customer Lists
Business Acquisition [Line Items]
Intangible assets																							16,575,000	16,575,000	13,453,000
Customer Lists \| Sugan Co, Ltd.
Business Acquisition [Line Items]
Useful life															5 years
Consideration payable															$ 1,200,000
License agreements
Business Acquisition [Line Items]
Intangible assets																							19,519,000	19,519,000	18,215,000
License agreements \| Pleuratech ApS
Business Acquisition [Line Items]
Useful life												15 years
Payments to acquire intangible assets																								2,000,000.0
Contingent liability												$ 5,000,000.0
Current royalty rate												6.00%
Intellectual Property \| IntelliMedical Technologies Pty Ltd
Business Acquisition [Line Items]
Total purchase price																					$ 11,900,000
Contingent liability																											$ 15.0
Current royalty rate									6.00%
Intellectual Property \| Lazarus Medical Technologies, LLC
Business Acquisition [Line Items]
Useful life													15 years
Payments to acquire intangible assets																								620,000
Contingent liability													$ 700,000
Current royalty rate													6.00%
Trademarks
Business Acquisition [Line Items]
Intangible assets																							23,412,000	23,412,000	11,538,000
Distribution agreements
Business Acquisition [Line Items]
Intangible assets																							$ 2,246,000	2,246,000	2,576,000
Distribution agreements \| QX Medical, LLC
Business Acquisition [Line Items]
Useful life					10 years
Distribution agreements \| Bluegrass Vascular Technologies, Inc. \| Investee
Business Acquisition [Line Items]
Useful life																		3 years
Intangible assets																		$ 1,000,000.0
Cagent Vascular, LLC
Business Acquisition [Line Items]
Preferred limited liability company units (in units) \| shares			1,786,000
Payments to purchase preferred limited liability company units			$ 2,200,000
Ownership interest (percent)			19.50%
Vascular Insights
Business Acquisition [Line Items]
Cash paid for merger at closing	$ 40,000,000
Weighted average useful life	11 years 9 months 18 days
Contingent liability	$ 20,000,000
Vascular Insights \| Developed technology
Business Acquisition [Line Items]
Useful life	12 years
Vascular Insights \| Customer Lists
Business Acquisition [Line Items]
Useful life	8 years
Vascular Insights \| Trademarks
Business Acquisition [Line Items]
Useful life	9 years
Cianna Medical, Inc.
Business Acquisition [Line Items]
Cash paid for merger at closing		$ 135,000,000
Weighted average useful life		10 years 8 months 12 days
Net sales related to acquisition																								6,300,000
Acquisition-related costs																								3,500,000
Total purchase price		$ 1,000,000
Cianna Medical, Inc. \| Developed technology
Business Acquisition [Line Items]
Useful life		11 years
Cianna Medical, Inc. \| Customer Lists
Business Acquisition [Line Items]
Useful life		8 years
Cianna Medical, Inc. \| Trademarks
Business Acquisition [Line Items]
Useful life		10 years
Cianna Medical, Inc. \| Achievement of Supply Chain and Scalability Metrics
Business Acquisition [Line Items]
Earn-out payment payable upon certain milestones		$ 15,000,000
Cianna Medical, Inc. \| Annual Net Sales Milestone
Business Acquisition [Line Items]
Earn-out payment payable upon certain milestones		$ 50,000,000
DirectACCESS Medical, LLC
Business Acquisition [Line Items]
Weighted average useful life				9 years 10 months 24 days
Total purchase price				$ 7,300,000
DirectACCESS Medical, LLC \| Developed technology
Business Acquisition [Line Items]
Useful life				10 years
DirectACCESS Medical, LLC \| Customer Lists
Business Acquisition [Line Items]
Useful life				5 years
DirectACCESS Medical, LLC \| Trademarks
Business Acquisition [Line Items]
Useful life				10 years
Becton, Dickinson and Company
Business Acquisition [Line Items]
Weighted average useful life							8 years
Net sales related to acquisition																								42,100,000
Acquisition-related costs																								1,800,000
Total purchase price							$ 100,300,000
Contingent liability							$ 1,600,000
Becton, Dickinson and Company \| Developed technology
Business Acquisition [Line Items]
Useful life							8 years
Becton, Dickinson and Company \| Customer Lists
Business Acquisition [Line Items]
Useful life							7 years
Becton, Dickinson and Company \| Trademarks
Business Acquisition [Line Items]
Useful life							9 years
ITL Healthcare Pty Ltd
Business Acquisition [Line Items]
Net sales related to acquisition																								8,000,000.0	3,300,000
Total purchase price								$ 11,300,000
ITL Healthcare Pty Ltd \| Customer Lists
Business Acquisition [Line Items]
Useful life								7 years
Laurane Medical S.A.S.
Business Acquisition [Line Items]
Weighted average useful life										11 years 10 months 24 days
Total purchase price										$ 16,500,000
Contingent liability										$ 5,500,000
Laurane Medical S.A.S. \| Developed technology
Business Acquisition [Line Items]
Useful life										12 years
Laurane Medical S.A.S. \| Customer Lists
Business Acquisition [Line Items]
Useful life										1 year
Osseon LLC
Business Acquisition [Line Items]
Weighted average useful life											9 years
Net sales related to acquisition																								2,100,000	942,000
Total purchase price											$ 6,800,000
Osseon LLC \| Developed technology
Business Acquisition [Line Items]
Useful life											9 years
Osseon LLC \| Customer Lists
Business Acquisition [Line Items]
Useful life											8 years
Vascular Access Technologies, Inc.
Business Acquisition [Line Items]
Total purchase price																$ 5,000,000.0
Contingent liability																$ 4,900,000
Vascular Access Technologies, Inc. \| Developed technology
Business Acquisition [Line Items]
Useful life																15 years
Argon Medical Devices, Inc.
Business Acquisition [Line Items]
Weighted average useful life																	6 years
Net sales related to acquisition																								45,500,000	41,200,000
Total purchase price																	$ 10,100,000
Total purchase price																	(797,000)
Argon Medical Devices, Inc. \| Cardiovascular Segment
Business Acquisition [Line Items]
Acquisition-related costs																									2,600,000
Argon Medical Devices, Inc. \| Previously Reported
Business Acquisition [Line Items]
Total purchase price																	$ 10,900,000
Argon Medical Devices, Inc. \| Developed technology
Business Acquisition [Line Items]
Useful life																	7 years
Argon Medical Devices, Inc. \| Customer Lists
Business Acquisition [Line Items]
Useful life																	5 years
Argon Medical Devices, Inc. \| Trademarks
Business Acquisition [Line Items]
Useful life																	5 years
Catheter Connections, Inc.
Business Acquisition [Line Items]
Weighted average useful life																	11 years 8 months 12 days
Net sales related to acquisition																								13,700,000	10,000,000.0
Total purchase price																	$ 38,000,000.0
Number of patents acquired \| patent																	40
Catheter Connections, Inc. \| Cardiovascular Segment
Business Acquisition [Line Items]
Acquisition-related costs																									482,000
Catheter Connections, Inc. \| Developed technology
Business Acquisition [Line Items]
Useful life																	12 years
Catheter Connections, Inc. \| Customer Lists
Business Acquisition [Line Items]
Useful life																	8 years
Catheter Connections, Inc. \| Trademarks
Business Acquisition [Line Items]
Useful life																	10 years
DFINE, Inc.
Business Acquisition [Line Items]
Weighted average useful life																			14 years 9 months 18 days
Net sales related to acquisition																								26,600,000	27,000,000.0	$ 13,500,000
Total purchase price																			$ 97,500,000
Total purchase price																						$ 1,100,000
Consideration paid related to net working capital adjustment																			578,000
Inventories																						89,000
Property and equipment																						109,000
Goodwill																						1,200,000
Measurement period adjustment, reduction in accrued expenses																						407,000
Measurement period adjustment, increase in deferred tax liabilities																						$ 113,000
Trade receivables acquired, gross																			4,300,000
Trade receivables, expected to be uncollectible																			$ 224,000
DFINE, Inc. \| Cardiovascular Segment
Business Acquisition [Line Items]
Acquisition-related costs																										1,600,000
DFINE, Inc. \| Developed technology
Business Acquisition [Line Items]
Useful life																			15 years
DFINE, Inc. \| Customer Lists
Business Acquisition [Line Items]
Useful life																			9 years
DFINE, Inc. \| Trademarks
Business Acquisition [Line Items]
Useful life																			15 years
HeRO®Graft
Business Acquisition [Line Items]
Weighted average useful life																				9 years 9 months 18 days
Total purchase price																				$ 18,500,000
Income since acquisition date																								$ 9,100,000	$ 8,600,000	$ 7,100,000
HeRO®Graft \| Developed technology
Business Acquisition [Line Items]
Useful life																				10 years
HeRO®Graft \| Customer Lists
Business Acquisition [Line Items]
Useful life																				12 years
HeRO®Graft \| Trademarks
Business Acquisition [Line Items]
Useful life																				5 years 6 months

Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Thousands										12 Months Ended
	May 23, 2018	Feb. 14, 2018	Oct. 02, 2017	Aug. 04, 2017	Jul. 03, 2017	May 01, 2017	Jan. 31, 2017	Jul. 06, 2016	Feb. 04, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 14, 2018	Nov. 13, 2018	Jan. 31, 2018
Assets Acquired
Goodwill										$ 335,433	$ 238,147	$ 211,927
Liabilities Assumed
Gain on bargain purchase										$ 0	$ (11,039)	$ 0
Vascular Insights
Assets Acquired
Inventories													$ 1,308
Goodwill													21,832
Total assets acquired													58,220
Vascular Insights \| Developed technology
Assets Acquired
Intangibles													32,830
Vascular Insights \| Customer lists
Assets Acquired
Intangibles													840
Vascular Insights \| Trademarks
Assets Acquired
Intangibles													$ 1,410
Cianna Medical, Inc.
Assets Acquired
Trade receivables														$ 6,151
Inventories														5,803
Prepaid expenses and other assets														315
Property and equipment														1,047
Other long-term assets														14
Goodwill														65,885
Total assets acquired														224,135
Liabilities Assumed
Trade payables														(1,497)
Accrued expenses														(2,384)
Deferred income tax liabilities														(30,363)
Other long-term liabilities														(1,527)
Total liabilities assumed														(35,771)
Total net assets acquired														188,364
Cianna Medical, Inc. \| Developed technology
Assets Acquired
Intangibles														134,510
Cianna Medical, Inc. \| Customer lists
Assets Acquired
Intangibles														3,330
Cianna Medical, Inc. \| Trademarks
Assets Acquired
Intangibles														$ 7,080
DirectACCESS Medical, LLC
Assets Acquired
Inventories	$ 971
Goodwill	938
Total assets acquired	7,269
Liabilities Assumed
Total purchase price	7,300
DirectACCESS Medical, LLC \| Developed technology
Assets Acquired
Intangibles	4,840
DirectACCESS Medical, LLC \| Customer lists
Assets Acquired
Intangibles	120
DirectACCESS Medical, LLC \| Trademarks
Assets Acquired
Intangibles	$ 400
Becton, Dickinson and Company
Assets Acquired
Inventories		$ 5,804
Property and equipment		748
Goodwill		9,728
Total assets acquired		101,880
Liabilities Assumed
Total purchase price		100,300
Becton, Dickinson and Company \| Developed technology
Assets Acquired
Intangibles		74,000
Becton, Dickinson and Company \| Customer lists
Assets Acquired
Intangibles		4,200
Becton, Dickinson and Company \| Trademarks
Assets Acquired
Intangibles		4,900
Becton, Dickinson and Company \| In Process Research and Development
Assets Acquired
Intangibles		$ 2,500
ITL Healthcare Pty Ltd
Assets Acquired
Trade receivables			$ 1,287
Other receivables			56
Inventories			1,808
Prepaid expenses and other assets			65
Property and equipment			1,053
Goodwill			3,945
Total assets acquired			14,154
Liabilities Assumed
Trade payables			(216)
Accrued expenses			(747)
Deferred income tax liabilities			(1,901)
Total liabilities assumed			(2,864)
Total net assets acquired			11,290
Total purchase price			11,300
ITL Healthcare Pty Ltd \| Customer lists
Assets Acquired
Intangibles			$ 5,940
Laurane Medical S.A.S.
Assets Acquired
Inventories				$ 594
Goodwill				6,366
Total assets acquired				22,000
Liabilities Assumed
Total purchase price				16,500
Laurane Medical S.A.S. \| Developed technology
Assets Acquired
Intangibles				14,920
Laurane Medical S.A.S. \| Customer lists
Assets Acquired
Intangibles				$ 120
Osseon LLC
Assets Acquired
Inventories					$ 979
Property and equipment					58
Goodwill					203
Total assets acquired					6,840
Liabilities Assumed
Total purchase price					6,800
Osseon LLC \| Developed technology
Assets Acquired
Intangibles					5,400
Osseon LLC \| Customer lists
Assets Acquired
Intangibles					$ 200
Vascular Access Technologies, Inc.
Assets Acquired
Goodwill						$ 4,281
Total assets acquired						9,900
Liabilities Assumed
Deferred income tax liabilities						(3,101)
Total purchase price						5,000
Vascular Access Technologies, Inc. \| Developed technology
Assets Acquired
Intangibles						7,800
Vascular Access Technologies, Inc. \| In Process Research and Development
Assets Acquired
Intangibles						$ 920
Argon Medical Devices, Inc.
Assets Acquired
Cash and cash equivalents							$ 1,436
Trade receivables							8,351
Inventories							11,222
Prepaid expenses and other assets							1,275
Income tax refund receivable							165
Property and equipment							2,319
Deferred tax assets							202
Total assets acquired							29,570
Liabilities Assumed
Trade payables							(2,414)
Accrued expenses							(5,083)
Income taxes payable							0
Deferred income tax liabilities							(934)
Total liabilities assumed							(8,431)
Total net assets acquired							21,139
Gain on bargain purchase							(11,039)
Total purchase price							10,100
Argon Medical Devices, Inc. \| Developed technology
Assets Acquired
Intangibles							2,200
Argon Medical Devices, Inc. \| Customer lists
Assets Acquired
Intangibles							1,500
Argon Medical Devices, Inc. \| Trademarks
Assets Acquired
Intangibles							900
Catheter Connections, Inc.
Assets Acquired
Trade receivables															$ 958
Inventories															2,157
Prepaid expenses and other assets															85
Property and equipment															1,472
Goodwill															8,989
Total assets acquired															38,361
Liabilities Assumed
Trade payables															(338)
Accrued expenses															(23)
Total liabilities assumed															(361)
Total net assets acquired															38,000
Total purchase price							$ 38,000
Catheter Connections, Inc. \| Developed technology
Assets Acquired
Intangibles															21,100
Catheter Connections, Inc. \| Customer lists
Assets Acquired
Intangibles															700
Catheter Connections, Inc. \| Trademarks
Assets Acquired
Intangibles															$ 2,900
DFINE, Inc.
Assets Acquired
Trade receivables								$ 4,054
Other receivables								6
Inventories								8,585
Prepaid expenses and other assets								630
Property and equipment								1,630
Other long-term assets								145
Goodwill								24,818
Total assets acquired								114,268
Liabilities Assumed
Trade payables								(1,790)
Accrued expenses								(5,298)
Deferred income tax liabilities								(701)
Deferred income tax liabilities - noncurrent								(10,844)
Total liabilities assumed								(18,633)
Total net assets acquired								95,635
Total purchase price								97,500
Cash received								1,327
DFINE, Inc. \| Developed technology
Assets Acquired
Intangibles								67,600
DFINE, Inc. \| Customer lists
Assets Acquired
Intangibles								2,400
DFINE, Inc. \| Trademarks
Assets Acquired
Intangibles								$ 4,400
HeRO®Graft
Assets Acquired
Inventories									$ 2,455
Property and equipment									290
Goodwill									2,555
Total assets acquired									18,500
Liabilities Assumed
Total purchase price									18,500
HeRO®Graft \| Developed technology
Assets Acquired
Intangibles									12,100
HeRO®Graft \| Customer lists
Assets Acquired
Intangibles									400
HeRO®Graft \| Trademarks
Assets Acquired
Intangibles									$ 700

Acquisitions - Summary of Unaudited Consolidated Results of Operations, Including Proforma Results (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
As Reported
Net Sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
Net income	$ 9,188	$ 16,619	$ 10,941	$ 5,269	$ 6,806	$ (3,569)	$ 9,483	$ 14,803	$ 42,017	$ 27,523	$ 20,121
Basic (in dollars per share)	$ 0.17	$ 0.31	$ 0.22	$ 0.10	$ 0.14	$ (0.07)	$ 0.19	$ 0.33	$ 0.80	$ 0.56	$ 0.45
Diluted (in dollars per share)	$ 0.16	$ 0.30	$ 0.21	$ 0.10	$ 0.13	$ (0.07)	$ 0.19	$ 0.32	$ 0.78	$ 0.55	$ 0.45
Pro Forma
Net Sales, Pro Forma									$ 928,336	$ 768,571	$ 664,366
Net Income, Pro Forma									$ 20,699	$ (13,720)	$ 23,054
Basic, Pro Forma (in dollars per share)									$ 0.40	$ (0.28)	$ 0.52
Diluted, Pro Forma (in dollars per share)									$ 0.38	$ (0.27)	$ 0.51

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Inventory Disclosure [Abstract]
Finished goods	$ 117,703	$ 86,555
Work-in-process	14,380	12,799
Raw materials	65,453	55,934
Total	$ 197,536	$ 155,288

Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill balance at January 1	$ 238,147	$ 211,927
Effect of foreign exchange	(1,304)	2,641
Additions as the result of acquisitions	98,590	23,579
Goodwill balance at December 31	$ 335,433	$ 238,147

Goodwill and Intangible Assets - Other Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 128,702	$ 97,680
Accumulated Amortization	(49,136)	(38,127)
Net Carrying Amount	79,566	59,553
Patents
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	19,378	16,528
Accumulated Amortization	(5,012)	(3,737)
Net Carrying Amount	14,366	12,791
Distribution agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,012	7,262
Accumulated Amortization	(5,766)	(4,686)
Net Carrying Amount	2,246	2,576
License agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	26,930	23,783
Accumulated Amortization	(7,411)	(5,568)
Net Carrying Amount	19,519	18,215
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	29,998	16,224
Accumulated Amortization	(6,586)	(4,686)
Net Carrying Amount	23,412	11,538
Covenants not to compete
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,028	1,028
Accumulated Amortization	(1,000)	(968)
Net Carrying Amount	28	60
Customer lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	39,936	31,935
Accumulated Amortization	(23,361)	(18,482)
Net Carrying Amount	16,575	13,453
In-process technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,420	920
Accumulated Amortization	0	0
Net Carrying Amount	$ 3,420	$ 920

Goodwill and Intangible Assets - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Accumulated impairment loss	$ 8,300,000	$ 8,300,000
Aggregate amortization expense	41,200,000	26,800,000	$ 19,300,000
Intangible asset impairment charges	657,000	809,000	$ 0
Quellent, LLC
Finite-Lived Intangible Assets [Line Items]
Intangible asset impairment charges	$ 657,000
Distal Access, LLC
Finite-Lived Intangible Assets [Line Items]
Intangible asset impairment charges		$ 809,000

Goodwill and Intangible Assets - Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2019	$ 58,035
2020	55,341
2021	48,084
2022	46,648
2023	$ 45,417

Income Taxes - Domestic and Foreign (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Domestic	$ 21,084	$ 14,531	$ 6,174
Foreign	28,435	21,350	19,212
INCOME BEFORE INCOME TAXES	$ 49,519	$ 35,881	$ 25,386

Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current expense (benefit):
Federal									$ (1,132)	$ 3,849	$ 1,933
State									582	645	492
Foreign									6,000	5,168	3,802
Total current expense									5,450	9,662	6,227
Deferred expense (benefit):
Federal									4,400	(314)	(144)
State									(667)	(216)	(195)
Foreign									(1,681)	(774)	(623)
Total deferred (benefit) expense									2,052	(1,304)	(962)
Total income tax expense	$ 3,022	$ 2,766	$ 624	$ 1,090	$ 4,474	$ 1,364	$ 1,830	$ 690	$ 7,502	$ 8,358	$ 5,265

Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Computed federal income tax expense at applicable statutory rate									$ 10,399	$ 12,559	$ 8,885
State income taxes									(59)	279	193
Tax credits									(1,734)	(1,377)	(1,164)
Production activity deduction									0	0	(53)
Foreign tax rate differential									(1,361)	(3,329)	(3,717)
Uncertain tax positions									267	(19)	597
Deferred compensation insurance assets									186	(479)	(307)
Transaction-related expenses									223	90	274
U.S. transition tax									(3,271)	10,612	0
TCJA remeasurement of deferred taxes									(71)	(8,383)	0
Stock-based payments									(4,278)	(2,264)	0
Bargain purchase gain									0	(1,570)	0
In-process research and development									0	1,486	0
Net GILTI									347	0	0
Foreign withholding tax									5,590	0	0
Other — including the effect of graduated rates									1,264	753	557
Total income tax expense	$ 3,022	$ 2,766	$ 624	$ 1,090	$ 4,474	$ 1,364	$ 1,830	$ 690	$ 7,502	$ 8,358	$ 5,265

Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred income tax assets:
Allowance for uncollectible accounts receivable	$ 606	$ 467
Accrued compensation expense	7,414	5,154
Inventory differences	1,269	2,505
Net operating loss carryforwards	20,226	15,741
Deferred revenue	46	58
Stock-based compensation expense	2,833	2,281
Other	9,243	8,986
Total deferred income tax assets	41,637	35,192
Deferred income tax liabilities:
Prepaid expenses	(1,142)	(930)
Property and equipment	(20,045)	(20,352)
Intangible assets	(58,883)	(28,588)
Foreign withholding tax	(5,590)	0
Other	(4,350)	(1,830)
Total deferred income tax liabilities	(90,010)	(51,700)
Valuation allowance	(4,989)	(4,422)
Net deferred income tax liabilities	(53,362)	(20,930)
Reported as:
Deferred income tax assets - Long-term	3,001	2,359
Deferred income tax liabilities - Long-term	(56,363)	(23,289)
Net deferred income tax liabilities	$ (53,362)	$ (20,930)

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net tax benefit related to reduction in U.S. corporate tax rate		$ 8,400,000
One-time tax expense resulting from transition tax		10,600,000
TCJA remeasurement of deferred taxes	$ 71,000	8,383,000	$ 0
U.S. transition tax	(3,271,000)	10,612,000	0
Net GILTI	347,000	0	0
Foreign withholding tax	$ 5,590,000	$ 0	$ 0
Statutory federal rate	21.00%	35.00%	35.00%
Increase in valuation allowance	$ 567,000	$ 636,000	$ 1,800,000
U.S federal net operating loss carryforwards	$ 86,300,000	67,900,000
Period to utilize the net operating loss carryforwards	17 years
NOL carryforward used in period	$ 11,900,000	9,100,000
Foreign operating loss carryforwards	5,900,000	5,400,000
Foreign operating loss carryforward, no expiration	5,200,000	4,900,000
Foreign operating loss carryforward, expiring	761,000	526,000
Unrecognized tax benefits including interest and penalties	3,300,000	3,100,000
Unrecognized tax benefits that would impact effective rate	3,000,000.0	2,700,000
Reduction of uncertain tax benefits related to certain liabilities for unrecognized tax benefits	307,000
Accrued interest and penalties	373,000	304,000
Income tax penalties and interest expense	69,000	$ 88,000	$ 30,000
Maximum
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Estimated decrease in unrecognized tax benefit in next twelve months	$ 400,000

Income Taxes - Summary of Income Tax Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, opening balance	$ 2,749	$ 2,549	$ 1,982
Gross increases in tax positions taken in a prior year	35	80	77
Gross increases in tax positions taken in the current year	586	403	856
Lapse of applicable statute of limitations	(423)	(283)	(366)
Unrecognized tax benefits, ending balance	$ 2,947	$ 2,749	$ 2,549

Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Payroll and related liabilities	$ 37,396	$ 30,225
Current portion of contingent liabilities	23,760	289
Advances from employees	540	796
Other accrued expenses	34,477	27,622
Total	$ 96,173	$ 58,932

Revolving Credit Facility and Long-Term Debt - Principal Balances under Long-term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 03, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Total long-term debt	$ 395,152		$ 278,472
Collateralized debt facility	7,000	$ 7,000	6,959
Less unamortized debt issuance costs	(348)		(487)
Less current portion	22,000		19,459
Long-term portion	373,152		259,013
Term Loan
Line of Credit Facility [Line Items]
Total long-term debt	72,500		85,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Total long-term debt	$ 316,000		$ 187,000

Revolving Credit Facility and Long-Term Debt - Narrative (Details) - USD ($)		12 Months Ended
	Sep. 03, 2018	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Collateralized debt facility	$ 7,000,000.0	$ 7,000,000	$ 6,959,000
Variable rate on loan		3.39%
Outstanding borrowings		$ 395,500,000
LIBOR
Line of Credit Facility [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Credit Agreement
Line of Credit Facility [Line Items]
Outstanding borrowings		388,500,000
Remaining borrowing capacity on line of credit		$ 58,300,000
Fixed interest rate percent			2.68%
Debt subject to fixed interest rate			$ 175,000,000.0
Credit Agreement \| Variable Rate 1
Line of Credit Facility [Line Items]
Variable interest rate percent		3.52%	2.82%
Debt subject to variable interest rate		$ 213,500,000	$ 97,000,000.0
Credit Agreement \| Interest Rate Swap 2
Line of Credit Facility [Line Items]
Fixed interest rate percent		2.12%
Debt subject to fixed interest rate		$ 175,000,000.0
Revolving Credit Facility \| Credit Agreement
Line of Credit Facility [Line Items]
Increase to revolving credit commitment			100,000,000
Maximum borrowing capacity			375,000,000
Interest rate increase if in event of default		2.00%
Revolving Credit Facility \| Credit Agreement \| Minimum
Line of Credit Facility [Line Items]
Commitment fee percentage		0.15%
Revolving Credit Facility \| Credit Agreement \| Maximum
Line of Credit Facility [Line Items]
Commitment fee percentage		0.40%
Term Loan \| Credit Agreement
Line of Credit Facility [Line Items]
Debt instrument, face amount			150,000,000
Bridge Loan \| Credit Agreement
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 25,000,000

Revolving Credit Facility and Long-Term Debt - Financial Covenants (Details) - Credit Agreement	12 Months Ended
	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Consolidated EBITDA	1.25
Consolidated Net Income	$ 0
Facility Capital Expenditures	$ 30,000,000
January 1, 2018 and thereafter
Debt Instrument [Line Items]
Consolidated Total Leverage Ratio	3.5

Revolving Credit Facility and Long-Term Debt - Future Minimum Payments on Long-term Debt (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Debt Disclosure [Abstract]
2019	$ 22,000
2020	17,500
2021	356,000
Total future minimum principal payments	$ 395,500

Derivatives - Narrative (Details) € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, £ in Thousands, kr in Thousands, kr in Thousands, SFr in Thousands, R$ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) hedge	Dec. 31, 2018 AUD ($) hedge	Dec. 31, 2018 CNY (¥) hedge	Dec. 31, 2018 DKK (kr) hedge	Dec. 31, 2018 MXN ($) hedge	Dec. 31, 2018 CHF (SFr) hedge	Dec. 31, 2018 KRW (₩) hedge	Dec. 31, 2018 CAD ($) hedge	Dec. 31, 2018 GBP (£) hedge	Dec. 31, 2018 JPY (¥) hedge	Dec. 31, 2018 SGD ($) hedge	Dec. 31, 2018 SEK (kr) hedge	Dec. 31, 2018 EUR (€) hedge	Dec. 31, 2018 HKD ($) hedge	Dec. 31, 2018 BRL (R$) hedge	Dec. 31, 2017 USD ($)	Aug. 05, 2016 USD ($)
Derivative [Line Items]
Deferred taxes used to offset fair value of interest rate swap	$ (2,200)															$ (2,200)
Maturity of derivative contract (up to)	2 years
Revenue and cost of sales
Derivative [Line Items]
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, gross	$ 27
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, net of tax	20
Interest expense
Derivative [Line Items]
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, gross	2,500
Amount expected to be reclassified from accumulated other comprehensive income to earnings in next twelve months, net of tax	1,900
Interest rate swap
Derivative [Line Items]
Notional amount of derivative																	$ 175,000
Fixed rate																	1.12%
Deferred taxes used to offset fair value of interest rate swap	$ (1,500)															$ (1,500)
Foreign currency forward contracts \| Designated as hedging instrument
Derivative [Line Items]
Average number of contracts entered into per month \| hedge	150	150	150	150	150	150	150	150	150	150	150	150	150	150	150
Foreign currency forward contracts \| Not designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative		$ 11,400	¥ 63,200	kr 3,237	$ 23,000	SFr 269	₩ 5,500,000	$ 2,300	£ 2,358	¥ 265,000	$ 8,500	kr 9,627	€ 5,927	$ 11,000	R$ 9,000
Average number of contracts entered into per month \| hedge	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20

Derivatives - Forward Notional Contracts (Details) - Dec. 31, 2018 - Foreign currency forward contracts € in Thousands, ₩ in Thousands, ¥ in Thousands, ¥ in Thousands, £ in Thousands, kr in Thousands, kr in Thousands, SFr in Thousands, R$ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands, $ in Thousands	AUD ($)	CNY (¥)	DKK (kr)	MXN ($)	CHF (SFr)	KRW (₩)	CAD ($)	GBP (£)	JPY (¥)	SGD ($)	SEK (kr)	EUR (€)	HKD ($)	BRL (R$)
Not designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative	$ 11,400	¥ 63,200	kr 3,237	$ 23,000	SFr 269	₩ 5,500,000	$ 2,300	£ 2,358	¥ 265,000	$ 8,500	kr 9,627	€ 5,927	$ 11,000	R$ 9,000
Derivatives designated as cash flow hedges \| Designated as hedging instrument
Derivative [Line Items]
Notional amount of derivative	$ 3,000	¥ 160,000	kr 17,225	$ 230,000	SFr 2,145	₩ 3,050,000	$ 4,410	£ 5,280	¥ 1,145,000		kr 30,210	€ 20,310

Derivatives - Fair Value of Derivative Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Designated as hedging instrument \| Interest rate swap \| Other assets (long-term)
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	$ 5,772	$ 5,749
Designated as hedging instrument \| Foreign currency forward contracts \| Other assets (long-term)
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	151	35
Designated as hedging instrument \| Foreign currency forward contracts \| Prepaid expenses and other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	613	363
Designated as hedging instrument \| Foreign currency forward contracts \| Accrued expenses
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	(711)	(468)
Designated as hedging instrument \| Foreign currency forward contracts \| Other long-term obligations
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	(101)	(82)
Not designated as hedging instrument \| Foreign currency forward contracts \| Prepaid expenses and other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	814	223
Not designated as hedging instrument \| Foreign currency forward contracts \| Accrued expenses
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	$ (796)	$ (841)

Derivatives - Amount of Gain (Loss) Recognized in OCI and Income Statement (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	$ 64
Amount of Gain/(Loss) recognized in OCI		$ 901	$ 4,784
Derivatives designated as cash flow hedges \| Interest rate swap
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	1,559
Amount of Gain/(Loss) recognized in OCI		853	4,989
Derivatives designated as cash flow hedges \| Interest rate swap \| Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) reclassified from AOCI	1,537
Amount of Gain/(Loss) reclassified from AOCI		95	(718)
Derivatives designated as cash flow hedges \| Foreign currency forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent	539
Amount of Gain/(Loss) recognized in OCI		491	(205)
Derivatives designated as cash flow hedges \| Foreign currency forward contracts \| Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) reclassified from AOCI	136
Amount of Gain/(Loss) reclassified from AOCI		(277)	21
Derivatives designated as cash flow hedges \| Foreign currency forward contracts \| Cost of goods sold
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain/(Loss) reclassified from AOCI	$ 361
Amount of Gain/(Loss) reclassified from AOCI		$ 625	$ (26)

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Commitments [Line Items]
Rent expense	$ 14,500	$ 13,600	$ 11,400
Deferred credits	2,300	2,400
Property, plant, and equipment grants from Ireland	142	147	170
Royalty expense	$ 5,300	$ 4,400	$ 3,200
Minimum
Other Commitments [Line Items]
Grant period	5 years
Maximum
Other Commitments [Line Items]
Grant period	8 years

Commitments and Contingencies - Schedule of Future Minimum Rental Payments for Operating Leases (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2019	$ 13,421
2020	11,319
2021	9,995
2022	8,053
2023	6,953
Thereafter	52,754
Total minimum lease payments	$ 102,495

Earnings Per Common Share (EPS) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share, Basic and Diluted [Abstract]
Net income, basic									$ 42,017	$ 27,523	$ 20,121
Basic (in shares)									52,268	48,805	44,408
Basic (in dollars per share)	$ 0.17	$ 0.31	$ 0.22	$ 0.10	$ 0.14	$ (0.07)	$ 0.19	$ 0.33	$ 0.80	$ 0.56	$ 0.45
Effect of dilutive stock options and warrants (in shares)									1,663	1,296	454
Net income, diluted									$ 42,017	$ 27,523	$ 20,121
Diluted (in shares)									53,931	50,101	44,862
Diluted (in dollars per share)	$ 0.16	$ 0.30	$ 0.21	$ 0.10	$ 0.13	$ (0.07)	$ 0.19	$ 0.32	$ 0.78	$ 0.55	$ 0.45
Antidilutive securities excluded from EPS (in shares)									396	381	727

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

+ References

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-Name Accounting Standards Codification
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+ Details

- Definition

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

+ References

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+ Details

Employee Stock Purchase Plan, Stock Options and Warrants - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized	$ 19.0
Compensation cost not yet recognized, period of recognition	3 years 1 month 2 days
Options granted in period (in shares)	692,000	1,300,000	880,000
Fair value of options, net of forfeitures	$ 11.1	$ 12.4	$ 5.2
Options granted in period, weighted average grant date fair value (in dollars per share)	$ 16.05	$ 9.57	$ 5.94
2006 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	2,900,000
2006 Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option contractual life	7 years
2006 Incentive Plan \| Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
2006 Incentive Plan \| Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	5 years
Employee Stock Purchase Plan Qualified
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant (in shares)	105,207
Purchase price for ESPP, percent of market price	95.00%

Employee Stock Purchase Plan, Stock Options and Warrants - Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	$ 6,117	$ 4,075	$ 2,506
Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	870	632	472
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	553	376	184
Selling, general, and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	$ 4,694	$ 3,067	$ 1,850

Employee Stock Purchase Plan, Stock Options and Warrants - Fair Value Calculation Assumptions (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate, minimum	2.63%	1.77%	1.15%
Risk-free interest rate, maximum	2.77%	1.83%	1.40%
Expected option life	5 years	5 years	5 years
Expected dividend yield	0.00%	0.00%	0.00%
Expected price volatility, minimum	34.06%	33.81%	34.28%
Expected price volatility, maximum	34.32%	34.07%	37.06%

Employee Stock Purchase Plan, Stock Options and Warrants - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total intrinsic value of stock options exercised	$ 25,692	$ 9,264	$ 3,648
Cash received from stock option exercises	8,510	5,552	4,577
Excess tax benefit from the exercise of stock options	$ 4,278	$ 2,264	$ 669
Number of Shares
Beginning balance (in shares)	3,623
Granted (in shares)	692
Exercised (in shares)	(690)
Forfeited/expired (in shares)	(118)
Outstanding at December 31 (in shares)	3,507	3,623
Exercisable (in shares)				1,101
Ending vested and expected to vest (in shares)				3,388
Weighted Average Exercise Price
Beginning balance (in dollars per share)	$ 26.30	$ 20.40		$ 26.30
Granted (in dollars per share)	46.45
Exercised (in dollars per share)	15.41
Forfeited/expired (in dollars per share)	26.90
Outstanding at December 31 (in dollars per share)	$ 26.30	$ 20.40
Exercisable (in dollars per share)				17.71
Ending vested and expected to vest (in dollars per share)				$ 26.05
Outstanding, remaining contractual term	4 years 6 months 14 days
Exercisable, remaining contractual term	3 years 3 months 29 days
Ending vested and expected to vest, remaining contractual term	4 years 6 months 3 days
Outstanding, intrinsic value				$ 103,483
Exercisable, intrinsic value				41,963
Ending vested and expected to vest, intrinsic value				$ 100,820

Employee Stock Purchase Plan, Stock Options and Warrants - Options Outstanding (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2018 $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise, lower (in dollars per share)	$ 9.95
Range of exercise, upper (in dollars per share)	$ 50.50
Number outstanding (in shares) \| shares	3,507
Number exercisable (in shares) \| shares	1,101
$9.95 - $13.99
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise, lower (in dollars per share)	$ 9.95
Range of exercise, upper (in dollars per share)	$ 16.05
Number outstanding (in shares) \| shares	982
Weighted Average Remaining Contractual Life (in years)	3 years 7 days
Weighted average exercise price (in dollars per share)	$ 13.99
Number exercisable (in shares) \| shares	585
Weighted average exercise price (in dollars per share)	$ 13.16
$16.05 - $21.98
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise, lower (in dollars per share)	16.41
Range of exercise, upper (in dollars per share)	$ 22.00
Number outstanding (in shares) \| shares	683
Weighted Average Remaining Contractual Life (in years)	3 years 8 months 23 days
Weighted average exercise price (in dollars per share)	$ 18.93
Number exercisable (in shares) \| shares	319
Weighted average exercise price (in dollars per share)	$ 18.76
$22.00 - $34.4
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise, lower (in dollars per share)	28.20
Range of exercise, upper (in dollars per share)	$ 28.20
Number outstanding (in shares) \| shares	961
Weighted Average Remaining Contractual Life (in years)	5 years 3 months 7 days
Weighted average exercise price (in dollars per share)	$ 28.20
Number exercisable (in shares) \| shares	159
Weighted average exercise price (in dollars per share)	$ 28.20
$38.35 - $38.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise, lower (in dollars per share)	34.40
Range of exercise, upper (in dollars per share)	$ 50.50
Number outstanding (in shares) \| shares	881
Weighted Average Remaining Contractual Life (in years)	6 years 14 days
Weighted average exercise price (in dollars per share)	$ 43.65
Number exercisable (in shares) \| shares	38
Weighted average exercise price (in dollars per share)	$ 34.74

Segment Reporting and Foreign Operations - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting [Abstract]
Number of operating segments \| segment									2
Segment Reporting Information [Line Items]
Net Sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
Foreign sales as a percent of total sales	44.00%				42.00%				44.00%	42.00%	39.00%
International
Segment Reporting Information [Line Items]
Net Sales									$ 386,340	$ 307,149	$ 233,488
Foreign sales									$ 92,700	$ 73,400	$ 59,900

Segment Reporting and Foreign Operations - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net Sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
United States
Disaggregation of Revenue [Line Items]
Net Sales									496,413	420,703	370,350
International
Disaggregation of Revenue [Line Items]
Net Sales									386,340	307,149	233,488
Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									849,477	700,613	580,151
Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									464,224	394,346	347,400
Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									385,253	306,267	232,751
Endoscopy
Disaggregation of Revenue [Line Items]
Net Sales									33,276	27,239	23,687
Stand-alone devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									361,613	275,456	191,127
Stand-alone devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									202,129	148,620	105,250
Stand-alone devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									159,484	126,836	85,877
Custom kits and procedure trays \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									134,756	126,089	119,247
Custom kits and procedure trays \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									92,975	92,474	93,109
Custom kits and procedure trays \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									41,781	33,615	26,138
Inflation devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									92,419	79,875	73,916
Inflation devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									31,717	31,848	35,506
Inflation devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									60,702	48,027	38,410
Catheters \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									155,525	127,747	113,367
Catheters \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									68,708	62,284	56,899
Catheters \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									86,817	65,463	56,468
Embolization devices \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									50,038	49,532	46,035
Embolization devices \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									20,433	22,374	24,075
Embolization devices \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									29,605	27,158	21,960
CRM/EP \| Cardiovascular
Disaggregation of Revenue [Line Items]
Net Sales									48,834	41,914	36,459
CRM/EP \| Cardiovascular \| United States
Disaggregation of Revenue [Line Items]
Net Sales									41,970	36,746	32,561
CRM/EP \| Cardiovascular \| International
Disaggregation of Revenue [Line Items]
Net Sales									6,864	5,168	3,898
Endoscopy devices \| Endoscopy
Disaggregation of Revenue [Line Items]
Net Sales									33,276	27,239	23,687
Endoscopy devices \| Endoscopy \| United States
Disaggregation of Revenue [Line Items]
Net Sales									32,189	26,357	22,950
Endoscopy devices \| Endoscopy \| International
Disaggregation of Revenue [Line Items]
Net Sales									$ 1,087	$ 882	$ 737

Segment Reporting and Foreign Operations - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 331,452	$ 292,820	$ 276,573
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	231,864	202,504	194,715
Ireland
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	45,283	45,671	47,337
Other foreign countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 54,305	$ 44,645	$ 34,521

Segment Reporting and Foreign Operations - Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Net Sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
Operating expenses									336,153	293,184	230,149
Operating income (loss)	13,661	21,061	15,114	8,781	13,219	879	13,362	5,609	58,617	33,069	34,876
Total other income (expense) - net									(9,098)	2,812	(9,490)
Income tax expense	3,022	2,766	624	1,090	4,474	1,364	1,830	690	7,502	8,358	5,265
NET INCOME	$ 9,188	$ 16,619	$ 10,941	$ 5,269	$ 6,806	$ (3,569)	$ 9,483	$ 14,803	42,017	27,523	20,121
Cardiovascular
Segment Reporting Information [Line Items]
Net Sales									849,477	700,613	580,151
Operating expenses									321,461	281,095	218,659
Operating income (loss)									49,289	24,819	30,053
Endoscopy
Segment Reporting Information [Line Items]
Net Sales									33,276	27,239	23,687
Operating expenses									14,692	12,089	11,490
Operating income (loss)									$ 9,328	$ 8,250	$ 4,823

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Segment Reporting and Foreign Operations - Assets, Depreciation, Amortization and Capital Expenditures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 1,620,012	$ 1,111,811	$ 942,803
Depreciation and amortization	69,546	53,582	43,755
Capital expenditures	63,324	38,623	32,837
Cardiovascular
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	1,588,970	1,103,806	932,927
Depreciation and amortization	68,722	52,700	42,806
Capital expenditures	63,032	38,437	32,613
Endoscopy
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	31,042	8,005	9,876
Depreciation and amortization	824	882	949
Capital expenditures	$ 292	$ 186	$ 224

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Employee Benefit Plans (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Contribution Plan Disclosure [Line Items]
Minimum age for participation (in years)	18 years
Minimum time at the company for participation (in days)	90 days
Total paid into 401(k)	$ 3.5	$ 2.4	$ 2.3
Foreign Plan
Defined Contribution Plan Disclosure [Line Items]
Total paid into 401(k)	$ 3.0	$ 2.3	$ 1.1
Foreign Plan \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Employer matching, percent of gross pay	2.00%
Foreign Plan \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Employer matching, percent of gross pay	32.00%
Foreign Plan \| Management \| Minimum
Defined Contribution Plan Disclosure [Line Items]
Employer matching, percent of gross pay	2.00%
Foreign Plan \| Management \| Maximum
Defined Contribution Plan Disclosure [Line Items]
Employer matching, percent of gross pay	32.00%

Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 233,249	$ 221,659	$ 224,810	$ 203,035	$ 190,897	$ 179,337	$ 186,549	$ 171,069	$ 882,753	$ 727,852	$ 603,838
Gross profit	104,666	102,039	100,009	88,056	85,656	80,514	84,141	75,942	394,770	326,253	265,025
Income from operations	13,661	21,061	15,114	8,781	13,219	879	13,362	5,609	58,617	33,069	34,876
Income tax expense	3,022	2,766	624	1,090	4,474	1,364	1,830	690	7,502	8,358	5,265
Net income	$ 9,188	$ 16,619	$ 10,941	$ 5,269	$ 6,806	$ (3,569)	$ 9,483	$ 14,803	$ 42,017	$ 27,523	$ 20,121
Basic (in dollars per share)	$ 0.17	$ 0.31	$ 0.22	$ 0.10	$ 0.14	$ (0.07)	$ 0.19	$ 0.33	$ 0.80	$ 0.56	$ 0.45
Diluted (in dollars per share)	$ 0.16	$ 0.30	$ 0.21	$ 0.10	$ 0.13	$ (0.07)	$ 0.19	$ 0.32	$ 0.78	$ 0.55	$ 0.45

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Fair Value Measurements - Financial Assets and (Liabilities) Carried at Fair Value (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate contracts	$ 0	$ 0
Foreign currency contract liabilities, current and long-term	0	0
Foreign currency contract liabilities, current and long-term	0	0
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate contracts	5,772	5,749
Foreign currency contract liabilities, current and long-term	1,578	621
Foreign currency contract liabilities, current and long-term	(1,608)	(1,391)
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate contracts	0	0
Foreign currency contract liabilities, current and long-term	0	0
Foreign currency contract liabilities, current and long-term	0	0
Estimate of Fair Value, Fair Value Disclosure
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest rate contracts	5,772	5,749
Foreign currency contract liabilities, current and long-term	1,578	621
Foreign currency contract liabilities, current and long-term	$ (1,608)	$ (1,391)

Fair Value Measurements - Liability Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - Contingent Consideration - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 10,956	$ 683
Contingent consideration liability recorded as the result of acquisitions	72,209	10,400
Fair value adjustments recorded to income during the period	(698)	(66)
Contingent payments made	(231)	(61)
Ending balance	$ 82,236	$ 10,956

Fair Value Measurements - Fair Value Inputs, Liabilities, Quantitative Information (Details) $ in Thousands	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Contingent Consideration
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration liability	$ 82,236	$ 10,956	$ 683
Revenue-based Payments \| Contingent Consideration
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration liability	10,661	10,956
Supply chain milestone \| Contingent Consideration
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration liability	13,593
Revenue milestones
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration liability	57,982
Other Payments
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration asset	$ 607
Other Payments \| Contingent Consideration
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Contingent consideration asset		$ 760
Measurement Input, Discount Rate \| Revenue-based Payments \| Minimum \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.099	0.099
Measurement Input, Discount Rate \| Revenue-based Payments \| Maximum \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.25	0.15
Measurement Input, Discount Rate \| Supply chain milestone \| Contingent Consideration \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.053
Measurement Input, Discount Rate \| Revenue milestones \| Minimum \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.03
Measurement Input, Discount Rate \| Revenue milestones \| Maximum \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.13
Measurement Input, Discount Rate \| Other Payments \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent receivable asset	0.10
Measurement Input, Discount Rate \| Other Payments \| Contingent Consideration \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent receivable asset		0.10
Milestone Payment Probability \| Supply chain milestone \| Contingent Consideration \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent liability	0.95
Milestone Payment Probability \| Other Payments \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent receivable asset	0.67
Milestone Payment Probability \| Other Payments \| Contingent Consideration \| Discounted Cash Flow \| Fair Value, Inputs, Level 3
Fair Value Measurements Inputs and Valuation Techniques [Line Items]
Unobservable inputs, contingent receivable asset		0.75

Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of other assets	$ 814	$ 988	$ 101
Other Payments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Remaining contingent receivable asset	607
Other Payments \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Remaining contingent receivable asset		760
Contingent Receivable \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payments collected	153
Gain (loss) on contingent receivable		(232)
Other Long-term Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability, noncurrent	58,500	10,700
Accrued expenses
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability, current	23,800	289
Other assets (long-term) \| Contingent Receivable \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Remaining contingent receivable asset		319
Other Current Assets \| Contingent Receivable \| Contingent Consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Remaining contingent receivable asset	$ 607	$ 441

Issuance of Common Stock (Details) - USD ($) $ in Thousands			12 Months Ended
Issuance of Common Stock (Details) - USD ($) $ in Thousands	Jul. 30, 2018	Mar. 28, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity [Abstract]
Common stock shares issued (in shares)	4,025,000	5,175,000	54,893,000	50,248,000
Proceeds from issuance of common stock	$ 205,000	$ 136,600	$ 214,993	$ 143,810	$ 5,271
Underwriting discounts and commissions	12,000	8,800
Other direct costs incurred	$ 366	$ 816	$ 366	$ 816	$ 0

Schedule II - Valuation and qualifying accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ (1,769)	$ (1,587)	$ (1,297)
Additions Charged to Costs and Expenses	(1,055)	(1,012)	(612)
Deduction	469	830	322
Balance at End of Year	(2,355)	(1,769)	(1,587)
Tax Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	(4,422)	(3,786)	(1,981)
Additions Charged to Costs and Expenses	(567)	(636)	(1,805)
Deduction	0	0	0
Balance at End of Year	$ (4,989)	$ (4,422)	$ (3,786)

Organization and Summary of Significant Accounting Policies - Organization (Details)	12 Months Ended
	Dec. 31, 2018 product_group segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating segments \| segment	2
Number of core product groups \| product_group	6

Organization and Summary of Significant Accounting Policies - Deferred Compensation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Cash surrender value of life insurance	$ 11,700	$ 11,700
Deferred compensation cost	$ 11,219	$ 11,181