Merit Medical Systems (MMSI) 10-K 1 Mar 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2018	Feb. 26, 2019	Jun. 29, 2018
Document Information [Abstract]
Entity Registrant Name	MERIT MEDICAL SYSTEMS INC
Entity Central Index Key	856,982
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	2,018
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

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 (Pa

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 INCO

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 COMP

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 STOC

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

CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
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

CONSOLIDATED STATEMENTS OF CA_2

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net capitalized interest	$ 647	$ 513	$ 460
Common Stock
Company's common stock surrendered in exchange for the exercise of stock options (in shares)	43	0	14

Organization and Summary of Sig

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. 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). 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.

Revenues

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

Acquisitions

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 c

Inventories

Inventories	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Inventories	INVENTORIES Inventories at December 31, 2018 and 2017 , consisted of the following (in thousands): 2018 2017 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 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 no t 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

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

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2018
Payables and Accruals [Abstract]
Accrued Expenses	ACCRUED EXPENSES Accrued expenses at December 31, 2018 and 2017 , consisted of the following (in thousands): 2018 2017 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 L

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

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

Commitments and Contingencies

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.

Earnings Per Common Share (EPS)

Earnings Per Common Share (EPS)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share, Basic and Diluted [Abstract]
Earnings Per Common Share (EPS)	EARNINGS PER COMMON SHARE (EPS) The computation of weighted average shares outstanding and the basic and diluted earnings per common share for the following periods consisted of the following (in thousands, except per share amounts): Net Income Shares Per Share Amount Year ended December 31, 2018: Basic EPS $ 42,017 52,268 $ 0.80 Effect of dilutive stock options and warrants 1,663 Diluted EPS $ 42,017 53,931 $ 0.78 Year ended December 31, 2017: Basic EPS $ 27,523 48,805 $ 0.56 Effect of dilutive stock options and warrants 1,296 Diluted EPS $ 27,523 50,101 $ 0.55 Year ended December 31, 2016: Basic EPS $ 20,121 44,408 $ 0.45 Effect of dilutive stock options and warrants 454 Diluted EPS $ 20,121 44,862 $ 0.45 For the years ended December 31, 2018 , 2017 and 2016 , approximately 396,000 , 381,000 and 727,000

Employee Stock Purchase Plan, S

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 O

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

Employee Benefit Plans	12 Months Ended
	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

Quarterly Results of Operations

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

Fair Value Measurements

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 Projected year of payments 2018-2037 Supply chain milestone $ 13,593 Discounted cash flow Discount rate 5.3% contingent liability Probability of milestone payment 95% Projected year of payments 2019 Revenue milestones $ 57,982 Discounted cash flow Discount rate 3.3% - 13% contingent liability Projected year of payments 2019-2023 Contingent receivable $ 607 Discounted cash flow Discount rate 10% asset 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 Projected year of payments 2017-2037 Contingent receivable $ 760 Discounted cash flow Discount rate 10% asset 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).

Issuance of Common Stock

Issuance of Common Stock	12 Months Ended
	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

Schedule II - Valuation and qua

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 Additions Charged to Deduction (b) Balance at 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 Additions Charged to Deduction Balance at TAX VALUATION ALLOWANCE: 2016 (1,981 ) (1,805 ) — (3,786 ) 2017 (3,786 ) (636 ) — (4,422 ) 2018 (4,422 ) (567 ) — (4,989 )

Organization and Summary of S_2

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	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	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 .
Receivables	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	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	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	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 . 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
Deferred Compensation	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.
Other Assets	Other Assets .
Deferred Credits	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/Shipping and Handling/Cost of Sales	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
Research and Development	Research and Development. Research and development costs are expensed as incurred.
Income Taxes	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	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	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.
Stock-Based Compensation	Stock-Based Compensation . We recognize the fair value compensation cost relating to stock-based payment transactions in accordance with ASC 718, Compensation — Stock Compensation
Concentration of Credit Risk	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.
Foreign Currency	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.
Derivatives	Derivatives . . 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 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.
New Financial Accounting Standards	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.

Organization and Summary of S_3

Organization and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Property and Equipment	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

Revenues (Tables)

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)

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 Inventories $ 1,308 Intangibles Developed technology 32,830 Customer list 840 Trademarks 1,410 Goodwill 21,832 Total assets acquired $ 58,220 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. Inventories $ 594 Intangibles Developed technology 14,920 Customer list 120 Goodwill 6,366 Total net assets acquired $ 22,000 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 Inventories $ 971 Intangibles Developed technology 4,840 Customer list 120 Trademarks 400 Goodwill 938 Total assets acquired $ 7,269 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 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 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 Intangibles Developed technology $ 7,800 In-process technology 920 Goodwill 4,281 Deferred tax liabilities (3,101 ) Total net assets acquired $ 9,900 Inventories $ 979 Property and equipment 58 Intangibles Developed technology 5,400 Customer list 200 Goodwill 203 Total net assets acquired $ 6,840 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	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

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2018
Inventory Disclosure [Abstract]
Schedule of Inventory	Inventories at December 31, 2018 and 2017 , consisted of the following (in thousands): 2018 2017 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 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)

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	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
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	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

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2018
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses at December 31, 2018 and 2017 , consisted of the following (in thousands): 2018 2017 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_2

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

Derivatives (Tables)

Derivatives (Tables)	12 Months Ended
	Dec. 31, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Notional Amounts of Outstanding Derivative Positions	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 8,500 150 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
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)	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 )
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

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	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

Earnings Per Common Share (EP_2

Earnings Per Common Share (EPS) (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share, Basic and Diluted [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The computation of weighted average shares outstanding and the basic and diluted earnings per common share for the following periods consisted of the following (in thousands, except per share amounts): Net Income Shares Per Share Amount Year ended December 31, 2018: Basic EPS $ 42,017 52,268 $ 0.80 Effect of dilutive stock options and warrants 1,663 Diluted EPS $ 42,017 53,931 $ 0.78 Year ended December 31, 2017: Basic EPS $ 27,523 48,805 $ 0.56 Effect of dilutive stock options and warrants 1,296 Diluted EPS $ 27,523 50,101 $ 0.55 Year ended December 31, 2016: Basic EPS $ 20,121 44,408 $ 0.45 Effect of dilutive stock options and warrants 454 Diluted EPS $ 20,121 44,862 $ 0.45

Employee Stock Purchase Plan,_2

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_2

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 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

Quarterly Results of Operatio_2

Quarterly Results of Operations (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	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

Fair Value Measurements (Tables

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 ) $ — (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.
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	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 Projected year of payments 2018-2037 Supply chain milestone $ 13,593 Discounted cash flow Discount rate 5.3% contingent liability Probability of milestone payment 95% Projected year of payments 2019 Revenue milestones $ 57,982 Discounted cash flow Discount rate 3.3% - 13% contingent liability Projected year of payments 2019-2023 Contingent receivable $ 607 Discounted cash flow Discount rate 10% asset 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 Projected year of payments 2017-2037 Contingent receivable $ 760 Discounted cash flow Discount rate 10% asset Probability of milestone payment 75% Projected year of payments 2018-2019

Organization and Summary of S_4

Organization and Summary of Significant Accounting Policies - Organization (Details)	12 Months Ended
	Dec. 31, 2018product_groupsegment
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 S_5

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 S_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

Organization and Summary of S_7

Organization and Summary of Significant Accounting Policies - Stock Based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Allocated share-based compensation	$ 6,117	$ 4,075	$ 2,506

Organization and Summary of S_8

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 S_9

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 _10

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

Revenues - Disaggregation of Re

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 (Detai

Acquisitions - Narrative (Details) $ in Millions

Dec. 14, 2018USD ($)

Nov. 13, 2018USD ($)

Jul. 31, 2018USD ($)shares

May 23, 2018USD ($)

May 18, 2018USD ($)

Apr. 06, 2018USD ($)

Feb. 14, 2018USD ($)

Oct. 02, 2017USD ($)

Sep. 01, 2017

Aug. 04, 2017USD ($)

Jul. 03, 2017USD ($)

Jul. 01, 2017USD ($)

Jun. 16, 2017USD ($)

May 23, 2017USD ($)shares

May 19, 2017USD ($)

May 01, 2017USD ($)

Jan. 31, 2017USD ($)patent

Dec. 19, 2016USD ($)shares

Jul. 06, 2016USD ($)

Feb. 04, 2016USD ($)

Sep. 30, 2017USD ($)

Dec. 31, 2016USD ($)shares

Dec. 31, 2018USD ($)

Dec. 31, 2018USD ($)

Dec. 31, 2017USD ($)shares

Dec. 31, 2016USD ($)shares

Sep. 30, 2017AUD ($)

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

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

Number of units acquired | shares

1,251,878

Percent owned

19.50%

Cost method investment

$ 4,000,000

Cagent Vascular, LLC | Limited Liability Company

Business Acquisition [Line Items]

Payments to acquire investment

$ 3,000,000

$ 3,000,000

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

Contingent liability

$ 5,000,000

Current royalty rate

6.00%

Intellectual Property | IntelliMedical Technologies Pty Ltd

Business Acquisition [Line Items]

Total purchase price

$ 11,900,000

Contingent liability

$ 15

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

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

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

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

Total purchase price

$ 38,000,000

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

$ 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 A

Acquisitions - Purchase Price Allocation (Details) - USD ($) $ in Thousands

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 Unaud

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)

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 Asset_2

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 Asset_3

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 Asset_4

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 Asset_5

Goodwill and Intangible Assets - Future Amortization Expense (Details) $ in Thousands	Dec. 31, 2018USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
2,019	$ 58,035
2,020	55,341
2,021	48,084
2,022	46,648
2,023	$ 45,417

Income Taxes - Domestic and For

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 In

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

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 Ass

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 (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	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	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 Incom

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)

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_3

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_4

Revolving Credit Facility and Long-Term Debt - Narrative (Details) - USD ($)	Sep. 03, 2018	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Collateralized debt facility	$ 7,000,000	$ 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
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
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
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_5

Revolving Credit Facility and Long-Term Debt - Financial Covenants (Details) - Credit Agreement	12 Months Ended
	Dec. 31, 2018USD ($)
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_6

Revolving Credit Facility and Long-Term Debt - Future Minimum Payments on Long-term Debt (Details) $ in Thousands	Dec. 31, 2018USD ($)
Debt Disclosure [Abstract]
2,019	$ 22,000
2,020	17,500
2,021	356,000
Total future minimum principal payments	$ 395,500

Derivatives - Narrative (Detail

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, 2018USD ($)hedge	Dec. 31, 2018AUD ($)hedge	Dec. 31, 2018CNY (¥)hedge	Dec. 31, 2018DKK (kr)hedge	Dec. 31, 2018MXN ($)hedge	Dec. 31, 2018CHF (SFr)hedge	Dec. 31, 2018KRW (₩)hedge	Dec. 31, 2018CAD ($)hedge	Dec. 31, 2018GBP (£)hedge	Dec. 31, 2018JPY (¥)hedge	Dec. 31, 2018SGD ($)hedge	Dec. 31, 2018SEK (kr)hedge	Dec. 31, 2018EUR (€)hedge	Dec. 31, 2018HKD ($)hedge	Dec. 31, 2018BRL (R$)hedge	Dec. 31, 2017USD ($)	Aug. 05, 2016USD ($)
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$ 9000
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

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$ 9000

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 Der

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 (L

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)

Derivatives - Gain (Loss) in th

Derivatives - Gain (Loss) in the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Not designated as hedging instrument | Foreign currency forward contracts | Other expense
Derivative [Line Items]
Gain (loss) on derivative	$ 4,147	$ (4,746)	$ 69

Commitments and Contingencies -

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_2

Commitments and Contingencies - Schedule of Future Minimum Rental Payments for Operating Leases (Details) $ in Thousands	Dec. 31, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,019	$ 13,421
2,020	11,319
2,021	9,995
2,022	8,053
2,023	6,953
Thereafter	52,754
Total minimum lease payments	$ 102,495

Earnings Per Common Share (EP_3

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

Employee Stock Purchase Plan,_3

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
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,_4

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,_5

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,_6

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,_7

Employee Stock Purchase Plan, Stock Options and Warrants - Options Outstanding (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2018$ / sharesshares
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
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_3

Segment Reporting and Foreign Operations - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Sep. 30, 2017USD ($)	Jun. 30, 2017USD ($)	Mar. 31, 2017USD ($)	Dec. 31, 2018USD ($)segment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
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_4

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_5

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_6

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

Segment Reporting and Foreign_7

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

Employee Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
	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	$ 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 Operatio_3

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

Fair Value Measurements - Finan

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 - Liabi

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

Fair Value Measurements - Fair Value Inputs, Liabilities, Quantitative Information (Details) $ in Thousands	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
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 - Narra

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 (Detai

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 q_2

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)