QuidelOrtho 10-K 15 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2018	Feb. 08, 2019	Jun. 30, 2018
Document And Entity Information [Abstract]
Entity Registrant Name	QUIDEL CORP /DE/
Entity Central Index Key	353,569
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
Trading Symbol	QDEL
Amendment Flag	false
Entity Common Stock, Shares Outstanding		39,446,667
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 2,294,280,391
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Shell Company	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 43,695	$ 36,086
Accounts receivable, net	58,677	67,046
Inventories	67,379	67,078
Assets held for sale	0	146,644
Prepaid expenses and other current assets	23,646	14,375
Total current assets	193,397	331,229
Property, plant and equipment, net	73,901	61,585
Goodwill	337,021	337,028
Intangible assets, net	175,029	203,827
Deferred tax asset—non-current	22,192	0
Other non-current assets	4,831	1,582
Total assets	806,371	935,251
Current liabilities:
Accounts payable	25,171	27,279
Accrued payroll and related expenses	19,210	15,926
Current portion of contingent consideration	3,983	6,293
Current portion of deferred consideration	44,000	46,000
Current portion of Revolving Credit Facility	0	10,000
Current portion of Convertible Senior Notes	54,379	0
Current portion of Term Loan	0	10,184
Other current liabilities	12,992	12,666
Total current liabilities	159,735	128,348
Convertible Senior Notes	0	149,868
Term Loan	0	227,394
Revolving Credit Facility	53,188	0
Deferred consideration - non-current	143,158	177,158
Contingent consideration - non-current	15,129	18,008
Deferred tax liability - non-current	0	430
Other non-current liabilities	9,577	6,941
Commitments and contingencies (Note 8)
Stockholders’ equity:
Preferred stock, $.001 par value per share; 5,000 shares authorized; none issued or outstanding at December 31, 2018 and 2017	0	0
Common stock, $.001 par value per share; 97,500 shares authorized; 39,386 and 34,540 shares issued and outstanding at December 31, 2018 and 2017, respectively	39	35
Additional paid-in capital	363,921	239,489
Accumulated other comprehensive loss	(139)	0
Retained earnings (accumulated deficit)	61,763	(12,420)
Total stockholders’ equity	425,584	227,104
Total liabilities and stockholders’ equity	$ 806,371	$ 935,251

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value per share	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share	$ 0.001	$ 0.001
Common stock, shares authorized	97,500,000	97,500,000
Common stock, shares issued	39,386,000	34,540,000
Common stock, shares outstanding	39,386,000	34,540,000

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 522,285	$ 277,743	$ 191,603
Cost of Goods and Services Sold	206,572	121,601	79,872
Gross profit	315,713	156,142	111,731
Research and development	51,649	33,644	38,672
Sales and marketing	108,987	67,248	50,436
General and administrative	44,951	29,192	26,351
Acquisition and integration costs	14,197	16,506	711
Total operating expenses	219,784	146,590	116,170
Operating income (loss)	95,929	9,552	(4,439)
Other expense, net	(24,283)	(17,588)	(12,181)
(Loss) gain on extinguishment of debt	(8,262)	0	421
Total other expense, net	(32,545)	(17,588)	(11,760)
Income (loss) before income taxes	63,384	(8,036)	(16,199)
(Benefit) provision for income taxes	(10,799)	129	(2,391)
Net income (loss)	$ 74,183	$ (8,165)	$ (13,808)
Basic earnings (loss) per share	$ 1.95	$ (0.24)	$ (0.42)
Diluted earnings (loss) per share	$ 1.86	$ (0.24)	$ (0.42)
Shares used in basic per share calculation	37,995	33,734	32,708
Shares used in diluted per share calculation	42,554	33,734	32,708

Consolidated Statements of Comp

Consolidated Statements of Comprehensive (Loss) Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 74,183	$ (8,165)	$ (13,808)
Other comprehensive (loss) income, net of tax
Changes in cumulative translation adjustment	(139)	53	(22)
Comprehensive income (loss)	$ 74,044	$ (8,112)	$ (13,830)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock [Member]	Additional paid-in capital [Member]	Accumulated other comprehensive income (loss) [Member]	Retained earnings [Member]	Convertible Debt [Member]
Beginning Balance at Dec. 31, 2015	$ 218,676	$ 33	$ 209,121	$ (31)	$ 9,553
Beginning Balance, shares at Dec. 31, 2015		33,323
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under equity compensation plans	9,365	$ 0	9,365
Issuance of common stock under equity compensation plans, shares		755
Stock-based compensation expense	7,134		7,134
Repurchases of common stock	(20,168)	$ 0	(20,168)
Repurchase of common stock, shares		(1,181)
Changes in cumulative translation adjustment, net of tax	(22)			(22)
Net income (loss)	(13,808)				(13,808)
Ending Balance at Dec. 31, 2016	200,630	$ 33	204,905	(53)	(4,255)
Ending Balance, shares at Dec. 31, 2016		32,897
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under equity compensation plans	26,079	$ 2	26,077
Issuance of common stock under equity compensation plans, shares		1,669
Stock-based compensation expense	9,048		9,048
Repurchases of common stock	(541)	$ 0	(541)
Repurchase of common stock, shares		(26)
Changes in cumulative translation adjustment, net of tax	53			53
Net income (loss)	(8,165)				(8,165)
Ending Balance at Dec. 31, 2017	227,104	$ 35	239,489	0	(12,420)
Ending Balance, shares at Dec. 31, 2017		34,540
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock under equity compensation plans	17,047	$ 0	17,047
Issuance of common stock under equity compensation plans, shares		1,237
Stock-based compensation expense	10,078		10,078
Repurchase of Convertible Senior Notes	(547)
Repurchases of common stock	(4,344)	$ 0	(4,344)
Repurchase of common stock, shares		(90)
Changes in cumulative translation adjustment, net of tax	(139)			(139)
Issuance of shares in exchange for Convertible Senior Notes	200,219	$ 4	200,215
Number of shares of common stock issued						3,699
Tax impact from the conversion of Convertible Senior Notes	2,162		2,162
Reduction for equity component of Convertible Senior Notes exchanged	(100,726)		(100,726)
Net income (loss)	74,183				74,183
Ending Balance at Dec. 31, 2018	$ 425,584	$ 39	$ 363,921	$ (139)	$ 61,763
Ending Balance, shares at Dec. 31, 2018		39,386

Consolidated Statements of Cash

Consolidated Statements of Cash Flows $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
OPERATING ACTIVITIES
Net income (loss)	$ 74,183	$ (8,165)	$ (13,808)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, amortization and other	46,266	30,762	22,796
Stock-based compensation expense	11,709	9,061	7,986
Amortization of debt discount and deferred issuance costs	3,952	6,022	5,891
Change in fair value of acquisition contingencies	1,114	(81)	(485)
Accretion of interest on deferred consideration	10,000	2,608	0
Amortization of inventory step-up to fair value	3,650	10,950	0
Change in deferred tax assets and liabilities	(20,458)	365	(2,603)
Loss (gain) on extinguishment of debt	8,262	0	(421)
Increase (Decrease) in Operating Capital
Accounts receivable	8,236	(42,052)	(6,265)
Inventories	(3,974)	362	859
Prepaid expenses and other current and non-current assets	(12,681)	(9,113)	(489)
Accounts payable	(331)	12,956	4,323
Accrued payroll and related expenses	1,674	7,130	(375)
Other current and non-current liabilities	4,743	6,904	(5,594)
Net cash provided by operating activities	136,345	27,709	11,815
INVESTING ACTIVITIES
Acquisitions of property, equipment and intangibles	(31,689)	(17,510)	(11,909)
Acquisition of other businesses, net of cash acquired	0	(14,451)	(5,061)
Acquisition of Triage and BNP Businesses	0	(399,798)	0
Proceeds from sale of Summers Ridge Property	146,644
Net cash provided by (used for) investing activities	114,955	(431,759)	(16,970)
FINANCING ACTIVITIES
Proceeds from issuance of Term Loan	0	245,000	0
Proceeds from issuance of Revolving Credit Facility	0	10,000	0
Proceeds from issuance of common stock	17,047	25,426	8,575
Payments of debt issuance costs	(513)	(8,682)	0
Payments on lease obligation	(130)	(98)	(540)
Payments on Revolving Credit Facility	(40,000)
Repurchases of common stock	(4,344)	(541)	(20,168)
Repurchases of Convertible Senior Notes	0	0	(4,459)
Payments on acquisition contingent consideration	(6,303)	(497)	(207)
Payments of deferred consideration	(46,000)
Payments of Term Loan	(161,813)
Transaction costs related to debt exchange	(2,002)
Net cash (used for) provided by financing activities	(244,058)	270,608	(16,799)
Effect of exchange rate changes on cash	367	20	(9)
Net increase (decrease) in cash and cash equivalents	7,609	(133,422)	(21,963)
Cash and cash equivalents, beginning of period	36,086	169,508	191,471
Cash and cash equivalents, at end of period	43,695	36,086	169,508
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Cash paid during the period for interest	7,929	9,137	6,488
Cash paid during the period for income taxes	6,923	1,274	490
NON-CASH INVESTING ACTIVITIES
Purchase of property, equipment and intangibles by incurring current liabilities	1,785	1,446	3,280
NON-CASH FINANCING ACTIVITIES
Decrease of accrued payroll and related expenses upon issuance of common stock	0	903	539
Receivable for stock option exercises	0	0	251
Deferred consideration for acquisition of BNP Business		$ 220,550	$ 0
Extinguishment of Convertible Senior Notes through issuance of stock	200,219
Principal amount of Term Loan exchanged for Revolving Credit Facility	$ 83,187

Company Operations and Summary

Company Operations and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Company Operations and Summary of Significant Accounting Policies	Company Operations and Summary of Significant Accounting Policies Quidel Corporation (the “Company”) commenced operations in 1979. The Company operates in one business segment, which develops, manufactures and markets rapid diagnostic testing solutions. These diagnostic tests can be categorized in the following product categories: Rapid Immunoassay, Cardiac Immunoassay, Specialized Diagnostic Solutions and Molecular Diagnostic Solutions. The Company sells its products directly to end users and distributors, in each case, for professional use in physician offices, hospitals, clinical laboratories, reference laboratories, leading universities, retail clinics and wellness screening centers. The Company markets its products through a network of distributors and a direct sales force and temporary transition service arrangements entered into with Abbott Laboratories in connection with the acquisition of the Triage and BNP Businesses. The accompanying consolidated financial statements of the Company and its subsidiaries have been prepared in accordance with generally accepted accounting principles in the U.S. Consolidation— The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated. Cash and Cash Equivalents— The Company considers cash equivalents to be highly liquid investments with a maturity at the date of purchase of three months or less. The Company invests its cash equivalents primarily in money market funds with high quality institutions. Accounts Receivable— The Company sells its products directly to hospitals and reference laboratories as well as to distributors in the U.S. and sells directly to hospitals and labs and through distribution internationally (see Note 9 ). The Company periodically assesses the financial strength of these customers and establishes reserves for anticipated losses when necessary, which historically have not been material. The Company’s reserves primarily consist of amounts related to cash discounts and contract rebates. The balance of accounts receivable is net of reserves of $12.0 million and $12.3 million at December 31, 2018 and 2017 , respectively. Concentration of Credit Risk— Financial instruments that potentially subject the Company to significant concentrations of credit risk consists principally of trade accounts receivable. The Company performs credit evaluations of its customers’ financial condition and limits the amount of credit extended when deemed necessary, but generally requires no collateral. Credit quality is monitored regularly by reviewing credit history. The Company believes that the concentration of credit risk in its trade accounts receivables is moderated by its credit evaluation process, relatively short collection terms, the high level of credit worthiness of its customers, and letters of credit issued on the Company’s behalf. Potential credit losses are limited to the gross value of accounts receivable. Inventories— Inventories are stated at the lower of cost (first-in, first-out) or net realizable value. The Company reviews the components of its inventory on a quarterly basis for excess, obsolete and impaired inventory and makes appropriate dispositions as obsolete stock is identified. Assets Held for Sale— Assets to be disposed that meet the held for sale criteria are reported at the lower of their carrying amount and fair value, less costs to sell, and are no longer depreciated. Property, Plant and Equipment— Property, plant and equipment is recorded at cost and depreciated over the estimated useful lives of the assets ( three to fifteen years) using the straight-line method. Amortization of leasehold improvements is computed on the straight-line method over the estimated useful lives of the assets. Goodwill and Intangible Assets— Intangible assets are recorded at cost and amortized on a straight-line basis over their estimated useful lives, except for indefinite-lived intangibles such as goodwill. Software development costs associated with software to be leased or otherwise marketed are expensed as incurred until technological feasibility has been established. After technological feasibility is established, software development costs are capitalized. The capitalized cost is amortized on a straight-line basis over the estimated product life or on the ratio of current revenues to total projected product revenues, whichever is greater. Convertible Debt— The Company accounts for convertible debt instruments that may be settled in cash upon conversion (including combination settlement of cash equal to the “principal portion” and delivery of the “share amount” in excess of the conversion value over the principal portion in shares of common stock and/or cash) by separating the liability and equity components of the instruments in a manner that reflects our nonconvertible debt borrowing rate. The Company determines the carrying amount of the liability component by measuring the fair value of similar debt instruments that do not have the conversion feature. If no similar debt instrument exists, the Company estimates fair value by using assumptions that market participants would use in pricing a debt instrument, including market interest rates, credit standing, yield curves and volatilities. Determining the fair value of the debt component requires the use of accounting estimates and assumptions. These estimates and assumptions are judgmental in nature and could have a significant impact on the determination of the debt component, and the associated non-cash interest expense. See Note 3 for additional discussion of the Convertible Senior Notes issued in December 2014. Revenue Recognition— The Company records revenues primarily from product sales. These revenues are recorded net of rebates and other discounts. These rebates and discounts are estimated at the time of sale, and are largely driven by various customer program offerings, including special pricing agreements, promotions and other volume-based incentives. Revenue is recognized when control of the products is transferred to the customers in an amount that reflects the consideration the Company expects to receive from the customers in exchange for those products and services. This process involves identifying the contract with a customer, determining the performance obligations in the contract and the contract price, allocating the contract price to the distinct performance obligations in the contract and recognizing revenue when the performance obligations have been satisfied. A performance obligation is considered distinct from other obligations in a contract when it provides a benefit to the customer either on its own or together with other resources that are readily available to the customer and is separately identified in the contract. A performance obligation is considered to be satisfied once the control of a product is transferred to the customer or the service is provided to the customer, meaning the customer has the ability to use and obtain the benefit of the goods or service. The Company recognizes revenue for satisfied performance obligations only when there are no uncertainties regarding payment terms or transfer of control. A portion of product sales includes revenues for diagnostic kits, which are utilized on leased instrument systems under the Company’s “reagent rental” program. The reagent rental program provides customers the right to use the instruments at no separate cost to the customer in consideration for a multi-year agreement to purchase annual minimum amounts of consumables (“reagents” or “diagnostic kits”). When an instrument is placed with a customer under a reagent rental agreement, the Company retains title to the equipment and it remains capitalized on the Company’s Consolidated Balance Sheets as property, plant and equipment, net. The instrument is depreciated on a straight-line basis over the lesser of the lease term or life of the instrument. Depreciation expense is recorded in cost of sales included in the Consolidated Statements of Operations. Instrument and consumables under the reagent rental agreements are deemed two distinct performance obligations. Though the instrument and consumables do not have any use to customers without one another, they are not highly interdependent because they do not significantly affect each other. The Company would be able to fulfill its promise to transfer the instrument even if its customers did not purchase any consumables and the Company would be able to fulfill its promise to provide the consumables even if customers acquired instruments separately . The contract price is allocated between these two performance obligations based on the relative standalone selling prices. The instrument is considered an operating lease and revenue allocated to the instrument will be separately disclosed, if material. Royalty income from the grant of license rights is recognized during the period in which the revenue is earned and the amount is determinable from the licensee. From time to time, the Company earns income from grants for research and commercialization activities. For the year ended December 31, 2016, the Company recognized $6.5 million as grant revenue related to the Bill and Melinda Gates Foundation to develop, manufacture and validate a quantitative, low-cost, nucleic acid assay for HIV drug treatment monitoring on the integrated Savanna MDx platform for use in limited resource settings. Cash payments received were restricted as to use until expenditures contemplated in the grant were incurred or committed. As of December 31, 2016, all payment related milestones have been achieved and all of the grant revenue was fully recognized. As such, the Company recognized no grant revenue during each of the twelve months ended December 31, 2017 and 2018. Research and Development Costs— Research and development costs are charged to operations as incurred. In conjunction with certain third-party service agreements, the Company is required to make periodic payments based on achievement of certain milestones. The costs related to these research and development services are also charged to operations as incurred. Product Shipment Costs— Product shipment costs are included in sales and marketing expense in the accompanying Consolidated Statements of Operations. Shipping and handling costs were $8.3 million , $3.7 million and $3.8 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Advertising Costs— Advertising costs are expensed as incurred. Advertising costs were $0.9 million , $0.5 million and $0.3 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Deferred Rent— The Company enters into lease arrangements for office space under non-cancelable operating leases. Certain of the operating lease agreements contain rent escalation provisions, which are considered in determining the straight-line rent expense to be recorded over the lease term. The lease term begins on the date of initial possession of the leased property for purposes of recognizing lease expense on a straight-line basis over the term of the lease. The Company does not assume renewals in the determination of the lease term unless the renewals are deemed to be reasonably assured at lease inception. The difference between rent expense and amounts paid under the Company’s lease agreements are recorded as deferred rent. Income Taxes— Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes, using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. The Company’s policy is to recognize the interest expense and penalties related to income tax matters as a component of the income tax provision. Fair Value of Financial Instruments — The Company uses the fair value hierarchy established in Accounting Standards Codification (“ASC”) Topic 820 , Fair Value Measurements and Disclosures, which requires that the valuation of assets and liabilities subject to fair value measurements be classified and disclosed by the Company in one of the following three categories: Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2: Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; and Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e. supported by little or no market activity). The carrying amounts of the Company’s financial instruments, including cash and cash equivalents, accounts receivables, accounts payable and accrued liabilities approximate their fair values due to their short-term nature. Product Warranty —The Company generally sells products with a limited product warranty and certain limited indemnifications. Due to product testing, the short time between product shipment and the detection and correction of product failures and a low historical rate of payments on claims, the historical activity and the related expense were not significant for the fiscal years presented. Stock-Based Compensation —Compensation expense related to stock options granted is recognized ratably over the service vesting period for the entire option. For stock options with graded vesting, the Company ensures that the cumulative amount of compensation expense recognized at the end of any reporting period at least equals the portion of the stock option that has vested at that date. The total number of stock options expected to vest is adjusted by estimated forfeiture rates. The Company determined the estimated fair value of each stock option on the date of grant using the Black-Scholes option valuation model. The fair value of restricted stock units is determined based on the closing market price of the Company’s common stock on the grant date. Compensation expense for time-based restricted stock units is measured at the grant date and recognized ratably over the vesting period. For purposes of measuring compensation expense for performance-based restricted stock units, the number of shares ultimately expected to vest is estimated at each reporting date based on management’s expectations regarding the relevant performance criteria. The grant date of the PSUs takes place when the grant is authorized and the specific achievement goals are communicated. Comprehensive Income (loss) —Comprehensive income (loss) includes unrealized gains and losses which are related to the cumulative translation adjustments excluded from the Company’s Consolidated Statements of Operations. Use of Estimates —The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures 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. Accounting Periods —Each of the Company’s fiscal quarters end on the Sunday closest to the end of the calendar quarter. The Company’s fiscal year ends are December 30, 2018, December 31, 2017 and January 1, 2017. For ease of reference, the calendar quarter end dates are used herein. Recent Accounting Pronouncements —In May 2014, the Financial Accounting Standards Board (“FASB”) issued guidance codified in Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers , which amends the guidance in former ASC 605, Revenue Recognition (“ASU 2014-09”). The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies are required to use more judgment and make more estimates than under prior authoritative guidance. These may include identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. The FASB has issued several amendments to the new standard, which include clarification of accounting guidance related to identification of performance obligations, intellectual property licenses and principal vs. agent considerations. ASU 2014-09 and all subsequent amendments (collectively, “ASC 606”) were effective for public entities for annual reporting periods beginning after December 15, 2017, including interim periods therein. The Company adopted ASC 606 on January 1, 2018, using the modified retrospective transition method applied to those contracts which were not completed as of that date. The cumulative effect of applying the new revenue standard to all incomplete contracts as of January 1, 2018 was not material and, therefore, did not result in an adjustment to opening retained earnings. The adoption of ASC 606 did not have a material impact on the Company’s consolidated financial position, results of operations, equity or cash flows as of the adoption date or for the year ended December 31, 2018 . In February 2016, the FASB issued guidance codified in ASU 2016-02 (Topic 842), Leases . The guidance requires a lessee to recognize a lease liability for the obligation to make lease payments and a right-of-use asset representing the right to use the underlying asset for the lease term on the balance sheet. Under ASU 2016-02, adoption was required on a modified retrospective transition basis for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. In July 2018, the FASB issued ASU 2018-11, which allows for an alternative method to adopt the lease standard by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption, with no adjustment to prior comparative periods. ASU 2016-02 and all subsequent amendments (collectively, “ASC 842”) are effective for public entities for annual reporting periods beginning after December 15, 2018, including interim periods therein. The Company will adopt ASC 842 on January 1, 2019 using the alternative method of adoption. We estimate that the impact of the adoption will be to add approximately $87.0 million in operating right-of-use assets; increase the current portion of operating lease liabilities and non-current operating lease liabilities by approximately $5.0 million and $85.0 million , respectively; and decrease current and non-current deferred rent by approximately $0.5 million and $2.5 million , respectively. There are no adjustments to retained earnings. In applying ASC 842, the Company will adopt the package of practical expedients which, among other things, allows the Company to carry forward its historical lease classification. Additionally, the Company will adopt a policy to exclude short-term leases from the calculation of the right-of-use assets and lease liabilities. In January 2017, the FASB issued guidance codified in ASU 2017-04, Intangibles-Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment (“ASU 2017-04”). Under this new guidance, an entity will no longer determine goodwill impairment by calculating the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit had been acquired in a business combination. Instead, an entity will compare the fair value of a reporting unit with its carrying amount and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The guidance is effective for fiscal years beginning after December 15, 2019 including interim periods therein. The Company is currently evaluating the impact of this guidance and expects to adopt the standard in the first quarter of 2020.

Balance Sheet Account Details (

Balance Sheet Account Details (Notes)	12 Months Ended
	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Supplemental Balance Sheet Disclosures [Text Block]	Balance Sheet Account Details Prepaid expenses and other current assets The following is a summary of prepaid expenses and other current assets (in thousands): December 31, 2018 2017 Receivables under transition service agreements $ 15,507 $ 7,509 Income taxes receivable 2,703 3,806 Prepaid expenses 4,508 2,898 Other 928 162 Total prepaid expenses and other current assets $ 23,646 $ 14,375 Inventories Inventories are stated at the lower of cost (first-in, first-out) or net realizable value. The following is a summary of inventories (in thousands): December 31, 2018 2017 Raw materials $ 24,292 $ 22,252 Work-in-process (materials, labor and overhead) 21,280 22,813 Finished goods (materials, labor and overhead) 21,807 22,013 Total inventories $ 67,379 $ 67,078 Property, Plant and Equipment The following is a summary of property, plant and equipment (in thousands): December 31, 2018 2017 Equipment, furniture and fixtures $ 89,285 $ 75,728 Building and improvements 37,335 34,994 Leased instruments 42,647 32,458 Land 1,080 1,080 Total property, plant and equipment, gross 170,347 144,260 Less: accumulated depreciation and amortization (96,446 ) (82,675 ) Total property, plant and equipment, net $ 73,901 $ 61,585 The equipment, furniture and fixtures category above includes construction in progress and instruments that have not been placed at a customer under a lease agreement. These items will be reclassified when the assets are placed in service. The total expense for depreciation of fixed assets and amortization of leasehold improvements was $17.7 million , $14.6 million and $13.4 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Maintenance and minor repairs are charged to operations as incurred. Goodwill and Intangible Assets The Company had goodwill of $337.0 million as of December 31, 2018 , which remains consistent with December 31, 2017 . Amortizable intangible assets consisted of the following (dollar amounts in thousands): December 31, 2018 December 31, 2017 Description Weighted-average useful life (years) Gross assets Accumulated amortization Net Gross assets Accumulated amortization Net Purchased technology 9.1 $ 112,100 $ (57,495 ) $ 54,605 $ 112,100 $ (49,614 ) $ 62,486 Customer relationships 7.0 122,389 (27,561 ) 94,828 122,404 (10,960 ) 111,444 License agreements 9.9 6,511 (4,530 ) 1,981 6,515 (3,980 ) 2,535 Patent and trademark costs 10.8 28,740 (7,624 ) 21,116 28,740 (4,917 ) 23,823 Software development costs 5.0 6,629 (4,130 ) 2,499 6,630 (3,091 ) 3,539 Total amortizable intangible assets $ 276,369 $ (101,340 ) $ 175,029 $ 276,389 $ (72,562 ) $ 203,827 Amortization expense related to the capitalized software costs was $1.0 million , $0.8 million and $0.5 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Amortization expense (including capitalized software costs) was $28.8 million , $16.1 million and $9.5 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. The expected future annual amortization expense of the Company’s intangible assets is as follows (in thousands): For the years ending December 31, Amortization expense 2019 $ 27,542 2020 27,144 2021 26,999 2022 26,468 2023 25,758 Thereafter 41,118 Total $ 175,029 Other current liabilities The following is a summary of other current liabilities (in thousands): December 31, 2018 2017 Customer incentives $ 7,516 $ 7,165 Accrued interest 347 442 Other 5,129 5,059 Total other current liabilities $ 12,992 $ 12,666

Debt

Debt	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt Convertible Senior Notes In December 2014, the Company issued $172.5 million aggregate principal amount of 3.25% Convertible Senior Notes due 2020. Debt issuance costs of approximately $5.1 million were primarily comprised of underwriters fees, legal, accounting, and other professional fees of which $4.2 million were capitalized and are recorded as a reduction to long-term debt and are being amortized using the effective interest method to interest expense over the six -year term of the Convertible Senior Notes. The remaining $0.9 million of debt issuance costs were allocated as a component of equity in additional paid-in capital. Deferred issuance costs related to the Convertible Senior Notes were $0.5 million and $2.1 million as of December 31, 2018 and 2017 , respectively. The holders of the Convertible Senior Notes may surrender their notes for conversion, subject to specified circumstances, into cash, shares of common stock, or a combination of cash and shares of common stock, at the election of the Company, based on an initial conversion rate, subject to adjustment, of 31.1891 shares per $1,000 principal amount of the Convertible Senior Notes (which represents an initial conversion price of approximately $32.06 per share) up until the business day immediately preceding September 15, 2020. This conversion may, in the discretion of the holder, occur in the following circumstances and to the following extent: (1) during any calendar quarter commencing after the calendar quarter ending on March 31, 2015, if the last reported sales price of the Company’s common stock, for at least 20 trading days (whether or not consecutive) in the period of 30 consecutive trading days ending on the last trading day of the calendar quarter immediately preceding the calendar quarter in which the conversion occurs, is more than 130% of the conversion price of the notes in effect on each applicable trading day; (2) during the five consecutive business day period following any five consecutive trading day period in which the trading price per $1,000 principal amount of the Convertible Senior Note for each such trading day was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such day; or (3) upon the occurrence of specified events described in the indenture for the Convertible Senior Notes. On or after September 15, 2020 until the close of business on the second scheduled trading day immediately preceding the stated maturity date, holders may surrender their notes for conversion at any time, regardless of the foregoing circumstances. In general, for each $1,000 in principal, the “principal portion” of cash upon settlement is defined as the lesser of $1,000, or the conversion value during the 25 -day observation period as described in the indenture for the Convertible Senior Notes. The conversion value is the sum of the daily conversion value, which is the product of the effective conversion rate divided by 25 days and the daily volume weighted-average price (“VWAP”) of the Company’s common stock. The “share amount” is the cumulative “daily share amount” during the observation period, which is calculated by dividing the daily VWAP into the difference between the daily conversion value (i.e., conversion rate x daily VWAP) and $1,000. The Company pays 3.25% interest per annum on the principal amount of the Convertible Senior Notes semi-annually in arrears in cash on June 15 and December 15 of each year. The effective interest rate during fiscal year 2018 was 6.6% . The Convertible Senior Notes mature on December 15, 2020. During the year ended December 31, 2018 , the Company recorded total interest expense of $6.1 million related to the Convertible Senior Notes of which $3.1 million related to the amortization of the debt discount and issuance costs and $3.0 million related to the coupon due semi-annually. During the year ended December 31, 2017 , the Company recorded total interest expense of $10.9 million related to the Convertible Senior Notes of which $5.5 million related to the amortization of the debt discount and issuance costs and $5.4 million related to the coupon due semi-annually. During the year ended December 31, 2016 , the Company recorded total interest expense of $10.9 million related to the Convertible Senior Notes of which $5.4 million related to the amortization of the debt discount and issuance costs and $5.5 million related to the coupon due semi-annually. If a fundamental change, as defined in the indenture for the Convertible Senior Notes, such as certain acquisitions, mergers, or a liquidation of the Company, occurs prior to the maturity date, subject to certain limitations, holders of the Convertible Senior Notes may require the Company to repurchase all or a portion of their Convertible Senior Notes for cash at a repurchase price equal to 100% of the principal amount of the Convertible Senior Notes to be repurchased, plus any accrued and unpaid interest to, but excluding, the repurchase date. The Company accounts separately for the liability and equity components of the Convertible Senior Notes in accordance with authoritative guidance for convertible debt instruments that may be settled in cash upon conversion. The guidance requires the carrying amount of the liability component to be estimated by measuring the fair value of a similar liability that does not have an associated conversion feature. Because the Company had no outstanding non-convertible public debt, the Company determined that senior, unsecured corporate bonds traded on the market represent a similar liability to the Convertible Senior Notes without the conversion option. Based on market data available for publicly traded, senior, unsecured corporate bonds issued by companies in the same industry with similar credit ratings and with similar maturity, the Company estimated the implied interest rate of its Convertible Senior Notes to be 6.9% , assuming no conversion option. Assumptions used in the estimate represent what market participants would use in pricing the liability component, which were defined as Level 2 observable inputs. The estimated implied interest rate was applied to the Convertible Senior Notes, which resulted in a fair value of the liability component of $141.9 million upon issuance, calculated as the present value of implied future payments based on the $172.5 million aggregate principal amount. The $30.7 million difference between the cash proceeds of $172.5 million and the estimated fair value of the liability component was recorded in additional paid-in capital, net of tax and issuance costs, as the Convertible Senior Notes were not considered redeemable. During the fourth quarter of 2018, the last reported sales price of the Company’s common stock was greater than 130% of the Convertible Senior Notes conversion price for 20 or more of the 30 consecutive trading days preceding the quarter-end. Consequently, the Convertible Senior Notes were convertible as of December 31, 2018 . If the Convertible Senior Notes were converted as of December 31, 2018 , the if-converted amount would exceed the principal by $1.6 million . The Convertible Senior Notes may be settled at the Company’s option in cash or a combination of cash and shares of common stock. Because the settlement could be in cash, the Convertible Senior Notes have been classified as short-term debt as of December 31, 2018 . During the year ended December 31, 2018 , the Company entered into separate, privately negotiated exchange agreements with certain holders of the notes. In addition, certain note holders requested conversion and the Company elected to issue shares of common stock in exchange for the notes. To measure the resulting loss as of the settlement dates, the applicable interest rates were estimated using Level 2 observable inputs and applied to the converted notes using the same methodology as in the issuance date valuation. The following table summarizes information about the settlement of the Convertible Senior Notes (in thousands): Year ended December 30, 2018 Principal amount settled $ 108,811 Number of shares of common stock issued 3,699 Loss on extinguishment of debt $ 2,303 The following table summarizes information about the equity and liability components of the Convertible Senior Notes (dollars in thousands). The fair values of the respective notes outstanding were measured based on quoted market prices: December 31, 2018 2017 Principal amount of Convertible Senior Notes outstanding $ 58,503 $ 167,314 Unamortized discount of liability component (3,637 ) (15,356 ) Unamortized deferred issuance costs (487 ) (2,090 ) Net carrying amount of liability component 54,379 149,868 Less: current portion 54,379 — Long-term debt $ — $ 149,868 Carrying value of equity component, net of issuance costs $ 10,092 $ 29,211 Fair value of outstanding Convertible Senior Notes $ 85,999 $ 257,245 Remaining amortization period of discount on the liability component 2 years 3 years Credit Agreement On October 6, 2017, the Company entered into a Credit Agreement (the “Credit Agreement”), which provided the Company with a $245.0 million senior secured term loan facility (the “Term Loan”) and a $25.0 million Revolving Credit Facility (“Revolving Credit Facility”) together (the “Senior Credit Facility”). On the closing date of the Credit Agreement, the Company borrowed the entire amount of the Term Loan and $10.0 million under the Revolving Credit Facility. The Company used the proceeds of the Term Loan along with its cash on hand, to pay (i) the consideration for the Triage Business and (ii) the fees and expenses incurred in connection with the acquisition of the Triage and BNP Businesses. During the first three quarters of 2018, the Company used cash on hand of $161.8 million to pay down a portion of the existing Term Loan. Separately, the Company also repaid the entire outstanding $10.0 million balance on its Revolving Credit Facility under the Credit Agreement. On August 31, 2018, the Company entered into an Amended and Restated Credit Agreement to replace the prior Credit Agreement. The Amended and Restated Credit Agreement provides the Company with a $175.0 million Revolving Credit Facility. In connection with the closing of the Amended and Restated Credit Agreement, the Company borrowed $83.2 million under the Revolving Credit Facility to settle the outstanding Term Loan principal of $83.2 million . During the fourth quarter of 2018, Company used cash on hand to repay $30.0 million in principal of the Revolving Credit Facility. The remaining balance of $53.2 million is due upon maturity on August 31, 2023. Due to the early payments on the Term Loan and the modification of the Credit Facility, the Company recorded losses on extinguishment of debt of $6.0 million during the year ended December 31, 2018 . The Amended and Restated Credit Agreement does not include any term loan component. Loans will bear interest at a rate equal to (i) the London Interbank Offered Rate (“LIBOR”) plus the “applicable rate” or (ii) the “base rate” (defined as the highest of (a) the Bank of America prime rate, (b) the Federal Funds rate plus one-half of one percent and (c) LIBOR plus one percent) plus the “applicable rate.” The initial applicable rate was 1.00% per annum for base rate loans and 2.00% per annum for LIBOR rate loans, and thereafter will be determined in accordance with a pricing grid based on the Company’s Consolidated Leverage Ratio (as defined in the Credit Agreement) ranging from 1.75% to 2.50% per annum for LIBOR rate loans and from 0.75% to 1.50% per annum for base rate loans. In addition, the Company pays a commitment fee on the unused portion of the Credit Agreement based on the Company’s Consolidated Leverage Ratio ranging from 0.15% to 0.30% per annum. The Amended and Restated Credit Agreement is guaranteed by certain material domestic subsidiaries of the Company (the “Guarantors”) and is secured by liens on substantially all of the assets of the Company and the Guarantors, excluding real property and certain other types of excluded assets, and contains affirmative and negative covenants that are customary for credit agreements of this nature. The negative covenants include, among other things, limitations on asset sales, mergers, indebtedness, liens, dividends and other distributions, investments and transactions with affiliates. The Amended and Restated Credit Agreement contains two financial covenants: (i) maximum Consolidated Leverage Ratio (as defined in the Amended and Restated Credit Agreement) as of the last day of each fiscal quarter of 3.50 to 1.00, which ratio may be increased to 4.50 to 1.00 in case of certain qualifying acquisitions; and (ii) a minimum Consolidated Fixed Charge Coverage Ratio (as defined in the Amended and Restated Credit Agreement) of 1.25 to 1.00 as of the end of any fiscal quarter for the most recently completed four fiscal quarters. The Company was in compliance with all financial covenants as of December 31, 2018 . Interest expense recognized on the Term Loan and the Revolving Credit Facility for the year ended December 31, 2018 totaled $5.7 million for the stated interest and commitment fee. Amortization of debt issuance costs associated with the Term Loan and the Revolving Credit Facility was $0.8 million for the year ended December 31, 2018 , and was recorded to interest expense in the Company’s Consolidated Statements of Operations.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Significant components of the (benefit) provision for income taxes are as follows (in thousands): December 31, 2018 2017 2016 Current: Federal $ — $ (615 ) $ (117 ) State 755 314 246 Foreign 6,575 57 84 Total current provision (benefit) 7,330 (244 ) 213 Deferred: Federal (9,970 ) 131 (2,545 ) State (7,944 ) 238 (63 ) Foreign (215 ) 4 4 Total deferred (benefit) provision (18,129 ) 373 (2,604 ) (Benefit) provision for income taxes $ (10,799 ) $ 129 $ (2,391 ) The Company’s income (loss) before income taxes was subject to taxes in the following jurisdictions for the following periods (in thousands): December 31, 2018 2017 2016 United States $ 46,592 $ (8,198 ) $ (16,426 ) Foreign 16,792 162 227 Income (loss) before income taxes $ 63,384 $ (8,036 ) $ (16,199 ) Significant components of the Company’s deferred tax assets and deferred tax liabilities as of December 31, 2018 and 2017 are shown below (in thousands): December 31, 2018 2017 Deferred tax assets: Net operating loss carryforwards $ 711 $ 3,924 Intangible assets 3,502 2,935 Sale-leaseback, net 617 628 Allowance for returns and discounts 4,541 5,358 Stock-based compensation 5,333 5,933 Tax credit carryforwards 12,246 5,247 Other, net 6,883 4,580 Total deferred tax assets 33,833 28,605 Valuation allowance for deferred tax assets (1,830 ) (15,204 ) Total deferred tax assets, net of valuation allowance 32,003 13,401 Deferred tax liabilities: Convertible Senior Notes (636 ) (3,633 ) Intangible assets (2,165 ) (2,935 ) Property, plant and equipment (7,010 ) (7,263 ) Total deferred tax liabilities (9,811 ) (13,831 ) Net deferred tax assets (liabilities) $ 22,192 $ (430 ) Management assesses the available positive and negative evidence to estimate if sufficient future taxable income will be generated to use the existing deferred tax assets. A significant piece of objective negative evidence evaluated in prior years was 3 years of cumulative pre-tax book losses. For the three years ended December 31, 2018, however, the Company has demonstrated positive cumulative pre-tax book income. Such objective positive evidence allows the Company to consider other subjective evidence, such as the Company’s projections for future profitability, to determine the realizability of its deferred tax assets. On the basis of this evaluation, during the quarter ended December 31, 2018 , the Company released $13.4 million of valuation allowance, which is shown as a deferred tax benefit during the period. The Company maintains a valuation allowance of $1.8 million , which represents the portion of the deferred tax asset that management could not conclude was more likely than not to be realized. The amount of the deferred tax assets considered realizable could be adjusted in the future based on changes in available positive and negative evidence. As of December 31, 2018 , the Company had no federal net operating loss (“NOL”) carryforwards. The Company had state NOLs of approximately $19.3 million which will begin to expire in 2029, unless previously utilized. The Company has federal research credits of $5.8 million which will begin to expire on December 31, 2032 , unless previously utilized. The Company has federal foreign tax credits of $2.4 million which will begin to expire on December 31, 2028 unless previously utilized. The Company has state research credits of $12.8 million , of which $12.4 million do not expire. The remaining $0.4 million begin to expire in 2028, unless previously utilized. Pursuant to Internal Revenue Code Sections 382 and 383, the Company’s use of its NOL and research credit carryforwards may be limited as a result of cumulative changes in ownership of more than 50% over a three -year period. As of December 31, 2018 , the Company does not believe any historical ownership change has limited the use of its NOLs or tax credit carryforwards. The reconciliation of income tax computed at the federal statutory rate to the provision (benefit) for income taxes from continuing operations is as follows (in thousands): Year ended December 31, 2018 2017 2016 Tax expense (benefit) at statutory tax rate $ 13,311 $ (2,812 ) $ (5,775 ) State tax (benefits), net of federal tax 1,526 (239 ) (390 ) Permanent differences 635 327 129 Federal and state research credits—current year (3,628 ) (484 ) (979 ) Accrual of uncertain tax positions — 142 43 Stock-based compensation (9,286 ) (5,851 ) — Impact of change in federal and state tax rate on revaluing deferred tax assets — 3,357 (4 ) Change in valuation allowance (13,374 ) 5,799 4,687 Foreign Derived Intangible Income Deduction (FDII) (786 ) — — Other 803 (110 ) (102 ) (Benefit) provision for income taxes $ (10,799 ) $ 129 $ (2,391 ) On December 22, 2017, the Tax Cuts and Jobs Act (the “Tax Act”) was enacted into legislation, which includes a broad range of provisions affecting businesses. The Tax Act significantly revises how companies compute their U.S corporate tax liability by, among other provisions, reducing the corporate tax rate from 35% to 21% for tax years beginning after December 31, 2017, implementing a territorial tax system, and requiring a mandatory one-time tax on U.S. owned undistributed foreign earnings and profits known as the transition tax. Pursuant to the SEC Staff Accounting Bulletin No. 118, Income Tax Accounting Implications of the Tax Cuts and Jobs Act (“SAB 118”), a company may select between one of three scenarios to determine a reasonable estimate arising from the Tax Act. Those scenarios are (i) a final estimate which effectively closes the measurement window; (ii) a reasonable estimate leaving the measurement window open for future revisions; and (iii) no estimate as the law is still being analyzed. The Company was able to provide a reasonable estimate for the provisional revaluation of deferred taxes and the effects of the transition tax on undistributed foreign earnings and profits for the period ended December 31, 2017 . During the quarter ended December 31, 2018 the Company completed its accounting for the impacts of the Tax Act. Additionally, the Company has elected to treat global intangible low taxed income (GILTI) as a period cost and will expense GILTI in the period it is incurred. Because of the Company’s current operational structure, there is minimal expected GILTI impacts for the year ended December 31, 2018 and future years. The Company recognizes liabilities for uncertain tax positions based on a two-step process. The first step is to evaluate the tax position for recognition by determining if the weight of available evidence indicates that it is more likely than not that the position will be sustained on audit, including resolution of related appeals or litigation processes, if any. The second step is to measure the tax benefit as the largest amount that is more than 50% likely of being realized upon settlement. While the Company believes that it has appropriate support for the positions taken on its tax returns, the Company regularly assesses the potential outcome of examinations by tax authorities in determining the adequacy of its provision for income taxes. The following table summarizes the activity related to the Company’s unrecognized tax benefits (in thousands): Year ended December 31, 2018 2017 2016 Beginning balance $ 9,565 $ 8,604 $ 7,684 (Decreases) increases related to prior year tax positions (558 ) 10 (10 ) Increases related to current year tax positions 6,238 951 773 Other — — 157 Ending balance $ 15,245 $ 9,565 $ 8,604 As of December 31, 2018 and 2017 , the unrecognized tax benefits of $15.2 million and $9.6 million , respectively, of which $9.3 million and $8.1 million , respectively, would reduce the Company’s annual effective tax rate, subject to the valuation allowance. The Company does not anticipate any significant decreases in its unrecognized tax benefits over the next 12 months. The Company’s policy is to recognize the interest expense and penalties related to income tax matters as a component of the income tax provision. The Company has accrued approximately $0.3 million of interest and penalties associated with uncertain tax positions as of the years December 31, 2018 and 2017 . Interest expense, net of accrued interest (reversed), was approximately $0.1 million for both of the years ended December 31, 2018 and 2017. There was no interest expense, net of accrued interest (reversed) in 2016. The Company is subject to periodic audits by domestic and foreign tax authorities; however, there are no known audits at this time. Due to the carryforward of unutilized net operating loss and credit carryovers, the Company’s federal tax years from 2009 and forward and state tax years 2001 and forward are subject to examination by tax authorities. The Company believes that it has appropriate support for the income tax positions taken on its tax returns and that its accruals for tax liabilities are adequate for all open years based on an assessment of many factors, including past experience and interpretations of tax law applied to the facts of each matter.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2018
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock. The Company’s certificate of incorporation, as amended, authorizes the issuance of up to five million preferred shares. The Board of Directors is authorized to fix the number of shares of any series of preferred stock and to determine the designation of such shares. However, the amended certificate of incorporation specifies the initial series and the rights of that series. No shares of preferred stock were outstanding as of December 31, 2018 , 2017 or 2016 . Equity Incentive Plan. The Company grants stock options, time-based restricted stock units (“RSUs”) and performance-based restricted stock units (“PSUs”) to employees and non-employee directors under its 2018 Equity Incentive Plan (the “2018 Plan”). The Company previously granted stock options under its 2016 Equity Incentive Plan (the “2016 Plan”), Amended and Restated 2010 Equity Incentive Plan (the “2010 Plan”) and the Amended and Restated 2001 Equity Incentive Plan (the “2001 Plan”). The 2016 Plan, 2010 Plan and 2001 Plan were terminated at the time of adoption of the 2018 Plan, but the terminated Plans continue to govern outstanding options granted thereunder. The Company has stock options, RSUs and PSUs outstanding, which were issued under each of these equity incentive plans to certain employees and directors. Stock options granted under these plans have terms ranging up to ten years, have exercise prices ranging from $10.25 to $53.27 per share, and generally vest over four years. As of December 31, 2018 , approximately 3.2 million shares remained available for grant under the 2018 Plan. Restricted Stock Units. The Company grants both RSUs and PSUs to certain officers, directors and management. Until the restrictions lapse, ownership of the affected restricted stock units granted to the Company’s officers, directors and management is conditional upon continuous employment with the Company. For the years ended December 31, 2018 , 2017 and 2016 , the Company granted approximately 0.2 million , 0.3 million and 0.7 million shares, respectively, of RSUs to Board of Directors, officers and management, which either have a time-based four -year vesting provision or performance-based vesting provisions. During the years ended December 31, 2018 and 2016 , RSUs were granted to certain members of the Board of Directors in lieu of cash compensation as a part of the Company’s non-employee director’s deferred compensation program. During the year ended December 31, 2017 , common stock was issued to certain members of the Board of Directors in lieu of cash compensation for these members that elected to participate and agree to hold the stock for the elected deferral period. The compensation expense associated with these RSU grants were $0.4 million , $0.1 million and $0.4 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Employee Deferred Bonus Compensation Program. For the year ended December 31, 2017, the deferred bonus compensation program was suspended temporarily by the Board of Directors. For the years ended December 31, 2018 and 2016, certain employees of the Company were eligible to participate in the Company’s deferred bonus compensation program with respect to any payments received under the Company’s cash incentive plan. Participating employees could elect to receive 50% or 100% of the cash value of their cash bonus in the form of fully vested, restricted stock units plus an additional premium as additional restricted stock units, issued under the 2016 Plan or 2018 Plan. The premium restricted stock units are subject to a one -year vesting requirement from the date of issuance. The additional premium will be determined based on the length of time of the deferral period selected by the participating employee as follows: (i) if one year from the date of grant, a premium of 10% on the amount deferred, (ii) if two years from the date of grant, a premium of 20% on the amount deferred, or (iii) if four years from the date of grant, a premium of 30% on the amount deferred. Employee Stock Purchase Plan. Under the Company’s Amended and Restated 1983 Employee Stock Purchase Plan (the “ESPP”), full-time employees are allowed to purchase common stock through payroll deductions (which cannot exceed 10% of the employee’s compensation) at the lower of 85% of fair market value at the beginning or end of each six -month purchase period. As of December 31, 2018 , 1,321,456 shares had been sold under the Plan, leaving 178,544 shares available for future issuance. Share Repurchase Program. On January 25, 2016, the Company’s Board of Directors authorized an amendment to extend the previously announced stock repurchase program. The Board of Directors has authorized the Company to repurchase up to an aggregate of $50.0 million in shares of our common stock under our stock repurchase program. Any shares of common stock repurchased under this program will no longer be deemed outstanding upon repurchase and will be returned to the pool of authorized shares. During the year ended December 31, 2016, 1,152,386 shares of outstanding common stock were repurchased under the Company’s previously announced share repurchase program for approximately $19.6 million . There were no repurchases during 2017 and this repurchase program expired on January 25, 2018. On December 12, 2018, the Board of Directors authorized a new stock repurchase program, pursuant to which up to $50.0 million of the Company’s shares of common stock may be purchased through December 12, 2020. There were no repurchases during 2018 and at December 31, 2018, $50.0 million remained available under the new repurchase program. Shares Reserved for Future Issuance. At December 31, 2018 , approximately 5.7 million shares of common stock were reserved under the Company’s equity incentive plan and 178,544 shares were reserved for purchases under the ESPP.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation For the years ended December 31, 2018 , 2017 and 2016 stock-based compensation expense was $11.7 million , $9.1 million and $8.0 million , respectively, of which $3.4 million , $4.1 million and $4.7 million , respectively, related to stock options and $6.7 million , $4.9 million and $2.4 million , respectively, related to restricted stock units. For the years ended December 31, 2018 , 2017 and 2016 , the Company recorded $1.6 million , $0.1 million and $0.9 million in stock-based compensation expense, respectively, associated with the deferred bonus compensation program, described in Note 5 . During the years ended December 31, 2018 and 2016, $1.6 million and $0.9 million , respectively, was initially recorded as a component of accrued payroll and related expenses. Since the employee Deferred Bonus Compensation Program was suspended in 2017, there was no component of stock-based compensation recorded to accrued payroll related expenses during the year ended December 31, 2017. Stock-based compensation expense related to stock options and restricted stock units was as follows (in thousands): Year ended December 31, 2018 2017 2016 Cost of sales $ 763 $ 579 $ 617 Research and development 2,266 1,886 1,551 Sales and marketing 2,843 2,129 1,189 General and administrative 5,837 4,467 4,629 Total stock-based compensation expense $ 11,709 $ 9,061 $ 7,986 Stock-based compensation expense capitalized to inventory and compensation expense related to the Company’s ESPP were not material for the years ended December 31, 2018 , 2017 and 2016 . Stock Options Compensation expense related to stock options granted is recognized ratably over the service vesting period for the entire option award. The estimated fair value of each stock option was determined on the date of grant using the Black-Scholes option valuation model with the following weighted-average assumptions: Year ended December 31, 2018 2017 2016 Risk-free interest rate 2.49 % 2.30 % 1.47 % Expected option life (in years) 6.29 6.63 6.59 Volatility rate 36 % 36 % 36 % Dividend rate — % — % — % The computation of the expected option life is based on a weighted-average calculation combining the average life of options that have already been exercised and post-vest cancellations with the estimated life of the remaining vested and unexercised options. The expected volatility is based on the historical volatility of the Company’s stock. The risk-free interest rate is based on the U.S. Treasury yield curve over the expected term of the option. The Company has never paid any cash dividends on its common stock, and does not anticipate paying any cash dividends in the foreseeable future. Consequently, the Company uses an expected dividend yield of zero in the Black-Scholes option valuation model. The Company’s estimated forfeiture rate is based on its historical experience and future expectations. The Company’s determination of fair value is affected by the Company’s stock price as well as a number of assumptions that require judgment. The weighted-average fair value per share was $18.76 , $8.99 and $6.00 for options granted during the years ended December 31, 2018 , 2017 and 2016 , respectively. The total intrinsic value was $38.2 million , $26.8 million and $4.5 million for options exercised during the years ended December 31, 2018 , 2017 and 2016 , respectively. As of December 31, 2018 , total unrecognized compensation expense related to stock options was approximately $4.4 million and the related weighted-average period over which it is expected to be recognized is approximately 1.7 years. The maximum contractual term of the Company’s stock options is ten years. A summary of the status of stock option activity for the years ended December 31, 2016 , 2017 and 2018 is as follows (in thousands, except price data and years): Number of Shares Weighted- average exercise price per share Weighted- average remaining contractual term (in years) Aggregate intrinsic value Outstanding at January 1, 2016 3,967 $ 17.44 Granted 677 15.48 Exercised (553 ) 13.76 Cancelled (150 ) 20.86 Outstanding at December 31, 2016 3,941 17.49 Granted 263 22.21 Exercised (1,527 ) 16.38 Cancelled (18 ) 24.91 Outstanding at December 31, 2017 2,659 18.54 Granted 159 46.50 Exercised (891 ) 17.07 Cancelled (50 ) 21.19 Outstanding at December 31, 2018 1,877 $ 21.53 5.98 $ 49,976 Vested and expected to vest at December 31, 2018 1,838 $ 21.34 5.93 $ 49,302 Exercisable at December 31, 2018 1,117 $ 19.28 4.83 $ 32,374 Restricted Stock Units The Company grants both time-based restricted stock units (“RSUs”) and performance-based restricted stock units (“PSUs”). The fair value of RSUs and PSUs is determined based on the closing market price of the Company’s common stock on the grant date. Compensation expense for RSUs is measured at the grant date and recognized ratably over the vesting period. A portion of the restricted stock granted in 2018 and 2017 is performance-based and vesting is tied to achievement of specific Company goals over a three-year time period, subject to early vesting upon achievement of the performance goals. For purposes of measuring compensation expense for PSUs, the number of shares ultimately expected to vest is estimated at each reporting date based on management’s expectations regarding the relevant performance criteria. There was no stock-based compensation expense related to PSUs for the year ended December 31, 2016. A summary of the status of restricted stock unit activity for the years ended December 31, 2016 , 2017 and 2018 is as follows (in thousands, except price data): Shares Weighted-average grant date fair value Non-vested at January 1, 2016 459 $ 21.61 Granted 185 16.14 Vested (120 ) 18.50 Forfeited (23 ) 20.80 Non-vested at December 31, 2016 501 20.37 Granted 349 22.34 Vested (100 ) 23.49 Forfeited (4 ) 18.69 Non-vested at December 31, 2017 746 20.88 Granted 242 49.97 Vested (296 ) 21.70 Forfeited (16 ) 28.40 Non-vested at December 31, 2018 676 $ 30.75 Since the employee Deferred Bonus Compensation Program was suspended in 2017, there were no restricted stock units issued in exchanged for the deferred bonus liability in 2018. In 2017 and 2016 , the Company issued approximately 0.1 million restricted stock units each year in exchange for the deferred bonus liability of $0.9 million and $0.5 million , respectively. The total amount of unrecognized compensation expense related to non-vested restricted stock units as of December 31, 2018 was approximately $12.1 million , which is expected to be recognized over a weighted-average period of approximately 2.1 years.

Earnings (Loss) Per Share (Note

Earnings (Loss) Per Share (Notes)	12 Months Ended
	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Earnings Per Share [Text Block]	Earnings (Loss) Per Share Basic earnings (loss) per share (“EPS”) is computed by dividing net income (loss) by the weighted-average number of common shares outstanding. Diluted EPS is computed based on the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Potentially dilutive common shares consist of shares issuable from stock options, unvested RSUs and the 3.25% Convertible Senior Notes. Potentially dilutive common shares from outstanding stock options and unvested RSUs are determined using the average share price for each period under the treasury stock method. Potentially dilutive shares from the Convertible Senior Notes are determined using the if-converted method. Under the provisions of the if-converted method, the Convertible Senior Notes are assumed to be converted and the resulting commons shares are included in the denominator of the EPS calculation and the interest expense, net of tax, recorded in connection with the Convertible Senior Notes is added back to net income (loss). The Convertible Senior Notes have a dilutive impact when the average market price of the Company’s common stock exceeds the applicable conversion price of the notes. The Convertible Senior Notes became convertible on March 31, 2018 and remained convertible through December 31, 2018 . The following table reconciles net income (loss) and the weighted-average shares used in computing basic and diluted earnings per share in the respective periods (in thousands): Twelve months ended December 31, 2018 2017 2016 Numerator: Net income (loss) used for basic earnings per share $ 74,183 $ (8,165 ) $ (13,808 ) Interest expense on Convertible Senior Notes, net of tax 4,927 — — Net income (loss) used for diluted earnings per share, if-converted method $ 79,110 $ (8,165 ) $ (13,808 ) Basic weighted-average common shares outstanding 37,995 33,734 32,708 Potentially dilutive shares issuable from Convertible Senior Notes, if-converted 2,850 — — Potentially dilutive shares issuable from stock options and unvested RSUs 1,709 — — Diluted weighted-average common shares outstanding, if-converted 42,554 33,734 32,708 Potentially dilutive shares excluded from calculation due to anti-dilutive effect 161 37 2,770 Potentially dilutive shares excluded from the calculation above represent stock options when the combined exercise price and unrecognized stock-based compensation are greater than the average market price for the Company’s common stock because their effect is anti-dilutive. The number of potentially dilutive shares issuable under the Convertible Senior Notes that would have been included in the diluted EPS calculation if the Company had earnings amounted to 1.4 million for the year ended December 31, 2017 . Stock options and RSUs that would have been included in the diluted EPS calculation if the Company had earnings amounted to 1.4 million and 0.8 million for the years ended December 31, 2017 and 2016 . No conversion premium existed on the Convertible Senior Notes as of December 31, 2016; therefore, there was no dilutive impact from the Convertible Senior Notes to diluted EPS during the year ended December 31, 2016.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Leases The Company leases its facilities and certain equipment. Commitments for minimum rentals under non-cancelable leases at the end of 2018 are as follows (in thousands): Years ending December 31, Operating Leases Lease obligation 2019 $ 9,940 $ 956 2020 10,601 967 2021 10,502 — 2022 8,965 — 2023 8,409 — Thereafter 86,797 — Total minimum lease payments $ 135,214 $ 1,923 Operating Leases —Rent expense under operating leases totaled approximately $10.2 million for the year ended December 31, 2018 , $2.1 million for the year ended December 31, 2017 and $2.2 million for the year ended December 31, 2016 . On January 5, 2018, the Company entered into a sale and leaseback transaction for the San Diego property on Summers Ridge Road (the “Summers Ridge Property”) that was acquired as part of the Triage Business from Alere discussed in Note 12. The Summers Ridge Property was included as assets held for sale on the Consolidated Balance Sheet as of December 31, 2017. The Company sold the Summers Ridge Property for a net consideration of $146.6 million . In addition, the Company entered into a lease agreement with the buyer to lease two of the four buildings on the Summers Ridge Property for an initial term of 15 years. The Summers Ridge lease is subject to certain must-take provisions related to two additional buildings, consisting of approximately 125,000 square feet, upon the expiration of certain leases with the tenants of the other portion of the Summers Ridge Property. The initial term can be extended by the Company for two additional 5 -year terms upon satisfaction of certain conditions. The future minimum lease payments above excludes one building for which the must-take clause has not been triggered. McKellar Court Lease Obligation —During 1999, the Company completed a sale and leaseback transaction of its San Diego facility at McKellar Court. The facility was sold for $15.0 million , of which $3.8 million was capital contributed by the Company. The sale was an all-cash transaction, netting the Company approximately $7.0 million . The Company is a 25% limited partner in the partnership that acquired the facility. The transaction was deemed a financing transaction under the guidance in ASC Topic 840-40, Accounting for Sales of Real Estate . The assets sold remain on the books of the Company and will continue to be depreciated over the estimated useful life. In December 2009, the Company amended the terms of its lease agreement for the McKellar Court property, which had no significant impact on the Company’s financial statements. The amended terms included a new ten -year lease term through December 31, 2019 , with options to extend the lease for up to three additional five -year periods. In the fourth quarter of 2015, the Company amended the terms of its lease agreement to extend the lease term through December 31, 2020. The options to extend the lease for up to three additional five -year periods commence at the new lease term date of December 31, 2020. The Company is amortizing the lease obligation over the new estimated lease term, including extensions. As the Company accounts for the lease as a financing transaction, the Company adjusted the implied interest rate so that the existing lease obligation is amortized to the end of the estimated lease term, including extensions. The Company has determined that the partnership is a variable interest entity (VIE). The Company is not, however, the primary beneficiary of the VIE as it does not absorb the majority of the partnership’s expected losses or receive a majority of the partnership’s residual returns. The Company made lease payments to the partnership of approximately $0.9 million for each of the years ended December 31, 2018 , 2017 and 2016 , respectively. Purchase Commitments The Company has $ 9.1 million in firm inventory purchase commitments as of December 31, 2018 , the majority of which will be purchased within the next twelve months. Litigation and Other Legal Proceedings In Beckman Coulter Inc. v. Quidel Corporation, which was filed in the Superior Court for the County of San Diego, California (the “Trial Court”), on November 27, 2017, Beckman Coulter Inc. (“Beckman”) alleges that a provision of an agreement between Quidel and Beckman violates state antitrust laws. Our acquisition of the BNP Business consisted of assets and liabilities relating to a contractual arrangement with Beckman (the “Beckman Agreement”) for the supply of antibodies and other inputs related to, and distribution of, the Triage® BNP Test for the Beckman Coulter Access Family of Immunoassay Systems. The Beckman Agreement further provides that Beckman, for a specified period, cannot research or develop an assay for use in the diagnosis of cardiac diseases that measures or detects the presence or absence of BNP or NT-pro-BNP (a related biomarker). In the lawsuit, Beckman asserts that this provision violates certain California antitrust laws and is unenforceable. Beckman contends that it has suffered damages due to this provision and seeks a declaration that this provision is void. On December 7, 2018, the Trial Court granted Beckman’s motion for summary adjudication of its first cause of action for declaratory relief (the “Order”), finding the challenged provision void under California law. On December 18, 2018, the Trial Court stayed the effect of the Order pending our petitioning the Fourth District Court of Appeal (the “Court of Appeal”) for a stay and review of the Order. On January 18, 2019, we filed a petition for writ of mandate with the Court of Appeal, seeking immediate appellate review of the Order and requesting a stay of the Order pending review. Beckman requested and obtained an extension to file a preliminary opposition to the writ petition, which is due on February 25, 2019. We intend to file a reply to the preliminary opposition, which will be due twenty days after the filing of the opposition. On February 7, 2019, the Trial Court stayed the remaining litigation on Beckman’s second cause of action pending a decision from the Court of Appeal on whether they will hear the merits of our writ petition. The Trial Court also vacated all deadlines in the case, including the trial date. The parties are to report back to the Trial Court once the Court of Appeal issues its decision on whether to review the merits of our writ petition. We continue to deny that the contractual provision is unlawful, deny any liability with respect to this matter, and intend to continue to vigorously defend ourselves. There are multiple factors that prevent us from being able to estimate the amount of loss, if any, that may result from this matter including: (1) we are vigorously defending ourselves and believe that we have a number of meritorious legal defenses; (2) there are unresolved questions of law and fact that could be important to the ultimate resolution of this matter; and (3) discovery is in the very early stages. Accordingly, at this time, we are not able to estimate a possible loss or range of loss that may result from this matter or to determine whether such loss, if any, would have a material adverse effect on our financial condition, results of operations or liquidity. From time to time, the Company is involved in other litigation and proceedings, including matters related to product liability claims, commercial disputes and intellectual property claims, as well as regulatory, employment, and other claims related to our business. The Company accrues for legal claims when, and to the extent that, amounts associated with the claims become probable and are reasonably estimable. The actual costs of resolving legal claims may be substantially higher or lower than the amounts accrued for those claims. For those matters as to which we are not able to estimate a possible loss or range of loss, we are not able to determine whether the loss will have a material adverse effect on our business, financial condition or results of operations or liquidity. No accrual has been recorded as of December 31, 2018 and December 31, 2017 related to such matters as they are not probable and/or reasonably estimable. Management believes that all such current legal actions, in the aggregate, will not have a material adverse effect on the Company. However, the resolution of, or increase in any accruals for, one or more matters may have a material adverse effect on the Company’s results of operations and cash flows. The Company also maintains insurance, including coverage for product liability claims, in amounts which management believes are appropriate given the nature of its business. Licensing Arrangements The Company has entered into various licensing and royalty agreements, which largely require payments by the Company based on specified product sales as well as the achievement of specified milestones. The Company had royalty and license expenses relating to those agreements of approximately $0.4 million , $0.6 million and $0.8 million for the years ended December 31, 2018 , 2017 and 2016 , respectively.

Industry and Geographic Informa

Industry and Geographic Information	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Industry and Geographic Information	The Company operates in one reportable segment. Sales to customers outside the U.S. represented 32% , 18% and 17% of total revenue for the years ended December 31, 2018 , 2017 and 2016 , respectively. As of December 31, 2018 and 2017 , balances due from foreign customers were $23.4 million and $18.8 million , respectively. The Company had sales to individual customers in excess of 10% of total revenue, as follows: Year ended December 31, 2018 2017 2016 Customer: A 19 % 20 % 15 % B 13 % 13 % 13 % C 12 % 21 % 16 % 44 % 54 % 44 % As of December 31, 2018 and 2017 , accounts receivable from individual customers with balances due in excess of 10% of total accounts receivable totaled $33.3 million and $44.4 million , respectively. The following presents long-lived assets (excluding intangible assets) and total net revenue by geographic territory (in thousands): Long-lived assets as of December 31, Total revenue for the years ended December 31, 2018 2017 2018 2017 2016 Domestic $ 72,569 $ 59,833 $ 354,895 $ 227,611 $ 158,244 Foreign 1,332 1,752 167,390 50,132 33,359 Total $ 73,901 $ 61,585 $ 522,285 $ 277,743 $ 191,603 Consolidated net revenues by product category are as follows (in thousands): Year ended December 31, 2018 2017 2016 Rapid Immunoassay $ 183,160 $ 165,099 $ 121,416 Cardiac Immunoassay 266,524 47,030 — Specialized Diagnostic Solutions 53,243 51,978 60,681 Molecular Diagnostic Solutions 19,358 13,636 9,506 Total revenues $ 522,285 $ 277,743 $ 191,603

Fair Value Measurement

Fair Value Measurement	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurement	Fair Value Measurement The following table presents the Company’s hierarchy for its assets and liabilities measured at fair value on a recurring basis as of the following periods (in thousands): December 31, 2018 December 31, 2017 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Contingent consideration $ — $ — $ 19,112 $ 19,112 $ — $ — $ 24,301 $ 24,301 Deferred consideration — 187,158 — 187,158 — 223,158 — 223,158 Total liabilities measured at fair value $ — $ 187,158 $ 19,112 $ 206,270 $ — $ 223,158 $ 24,301 $ 247,459 There were no transfers of assets or liabilities between Level 1, Level 2 and Level 3 categories of the fair value hierarchy during the years ended December 31, 2018 and 2017 . In connection with the acquisition of the BNP Business, the Company will pay up to $280.0 million in cash, of which $256.0 million is guaranteed and is considered deferred consideration and $24.0 million is contingent consideration. The fair value of the deferred consideration was determined to be $220.6 million on the acquisition date based on the net present value of cash payments using an estimated borrowing rate using a quoted price for a similar liability. The Company recorded $10.0 million for the accretion of interest on the deferred consideration in 2018. The fair value of contingent consideration on the acquisition date was $19.7 million and was calculated using a discounted probability weighted valuation model. Contingent consideration related to the acquisitions of BioHelix Corporation in May 2013, AnDiaTec GmbH & Co. KG in August 2013 and Immutopics, Inc. in March 2016, was $4.6 million as of December 31, 2017 . During the year ended December 31, 2018, the Company fully paid the BioHelix Corporation and AndiaTec GmbH & Co. KG related contingent consideration and the Immutopics, Inc. related contingent consideration of $0.3 million remained as of December 31, 2018 . The Company assesses the fair value of contingent consideration to be settled in cash related to these prior acquisitions using a discounted revenue model. Significant assumptions used in the measurement include revenue projections and discount rates. This fair value measurement of contingent consideration is based on significant inputs not observed in the market and thus represent Level 3 measurements. Due to changes in the estimated payments and a shorter discounting period related to the various contingent consideration liabilities, the fair value of the contingent consideration changed during the years ended 2018 , 2017 and 2016 . These changes resulted in loss of $1.1 million for 2018 recorded to general and administrative expenses in the Consolidated Statements of Operations and gains of $0.1 million and $0.5 million for the years 2017 and 2016 , respectively, recorded to cost of sales in the Consolidated Statements of Operations. Changes in estimated fair value of contingent consideration liabilities from December 31, 2017 through December 31, 2018 are as follows (in thousands): Contingent consideration liability (Level 3 measurement) Balance at December 31, 2017 $ 24,301 Cash payments (6,303 ) Net loss recorded for fair value adjustments 1,114 Balance at December 31, 2018 $ 19,112

Employee Benefit Plan

Employee Benefit Plan	12 Months Ended
	Dec. 31, 2018
Retirement Benefits [Abstract]
Employee Benefit Plan	Note 11. Employee Benefit Plan The Company has a defined contribution 401(k) plan (the “401(k) Plan”) covering all employees who are eligible to join the 401(k) Plan upon employment. Employee contributions are subject to a maximum limit by federal law. This Plan includes an employer match of 50% on the first 6% of pay contributed by the employee. The Company contributed approximately $2.6 million , $1.5 million and $1.5 million to the 401(k) Plan during the years ended December 31, 2018 , 2017 and 2016 , respectively

Acquisition

Acquisition	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Acquisition	On October 6, 2017, the Company closed on the acquisition of the Triage and BNP Businesses. The acquisition was accounted for in conformity with ASC Topic 805, Business Combinations . In connection with the acquisition of the Triage Business, the Company paid $399.8 million in cash and assumed certain liabilities. These acquisitions enhance the Company’s revenue profile and expand the Company’s geographic footprint and product diversity. The Company used proceeds from the Term Loan (defined and discussed in Note 3 ) of $245.0 million and cash on hand to pay (i) the consideration for the Triage Business and (ii) fees and expenses incurred in connection with the acquisition of the Triage and BNP Businesses. In connection with the acquisition of the BNP Business, the Company: (i) will pay (A) $16.0 million in cash plus up to an additional $24.0 million in contingent consideration, payable in five annual installments of up to $8.0 million , the first of which was due and paid on April 2018, (B) $240.0 million in cash, payable in six annual installments of $40.0 million each, the first of which was due and paid in April 2018 and (C) $0.2 million in cash for certain inventory related adjustments; and (ii) assumed certain liabilities. The purchase price consideration is as follows (in thousands): Cash consideration—Triage Business $ 399,798 Deferred consideration—BNP Business 220,550 Contingent consideration—BNP Business 19,700 Inventory related adjustment 205 Net consideration $ 640,253 The fair value of the deferred consideration was determined to be $220.6 million on the acquisition date based on the net present value of cash payments. The discount rate utilized was based on a quoted borrowing rate for a similar liability. The fair value of contingent consideration on the acquisition date of $19.7 million was calculated using a discounted probability weighted valuation model. The components of the purchase price allocation at the acquisition date is as follows: Prepaid expenses and other current assets $ 796 Assets held for sale 146,540 Inventories 52,205 Property, plant and equipment 10,608 Intangible assets 184,900 Goodwill 245,531 Other non-current assets 182 Total assets acquired 640,762 Other current liabilities (509 ) Total net assets and liabilities acquired $ 640,253 Goodwill represents the excess of the total purchase price over the fair value of the underlying net assets, largely arising from synergies expected to be achieved by the combined Company and the expanded revenue profile and product diversity. The goodwill is fully deductible for tax purposes. The fair value of the identified intangible assets was determined primarily using an income-based approach. Intangible assets are amortized on a straight-line basis over the respective amortization periods. The following sets forth results of the amounts assigned to the identifiable intangible assets acquired (in thousands): Intangible Asset Amortization period Fair value of assets acquired Purchased technology 10 years $ 52,400 Customer relationships 7 years 115,000 Trademarks 10 years 17,500 Total intangible assets $ 184,900

Selected Quarterly Financial Da

Selected Quarterly Financial Data (unaudited)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (unaudited)	Selected Quarterly Financial Data (unaudited) First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share data) 2018 Total revenues $ 169,143 $ 103,155 $ 117,399 $ 132,588 Gross profit $ 106,271 $ 57,668 $ 69,642 $ 82,132 Operating income (loss) $ 51,093 $ 404 $ 16,894 $ 27,538 Net income (loss) $ 33,958 $ (3,076 ) $ 10,822 $ 32,479 Basic income (loss) per share $ 0.96 $ (0.08 ) $ 0.28 $ 0.82 Diluted income (loss) per share $ 0.86 $ (0.08 ) $ 0.27 $ 0.78 2017 Total revenues $ 73,692 $ 38,267 $ 50,894 $ 114,890 Gross profit (1) $ 48,499 $ 18,826 $ 29,690 $ 59,127 Operating income (loss) $ 19,229 $ (11,027 ) $ (2,537 ) $ 3,887 Net income (loss) $ 14,290 $ (11,842 ) $ (5,525 ) $ (5,088 ) Basic income (loss) per share $ 0.43 $ (0.35 ) $ (0.16 ) $ (0.15 ) Diluted income (loss) per share $ 0.42 $ (0.35 ) $ (0.16 ) $ (0.15 )

Consolidated Valuation and Qual

Consolidated Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
Consolidated Valuation and Qualifying Accounts	SCHEDULE II QUIDEL CORPORATION CONSOLIDATED VALUATION AND QUALIFYING ACCOUNTS Description Balance at beginning of period Additions charged to expense or as reductions to revenue (1) Deductions (2) Balance at end of period (in thousands) Year ended December 31, 2018: Accounts receivable allowance $ 12,309 $ 65,142 $ (65,472 ) $ 11,979 Year ended December 31, 2017: Accounts receivable allowance $ 7,165 $ 36,449 $ (31,305 ) $ 12,309 Year ended December 31, 2016: Accounts receivable allowance $ 7,488 $ 28,329 $ (28,652 ) $ 7,165 (1) Represents charges associated primarily to accruals for early payment discounts, volume discounts and contract rebates recorded as reductions to revenue. Additions to allowance for doubtful accounts are recorded to sales and marketing expenses. (2) The deductions represent actual charges against the accrual described above.

Company Operations and Summar_2

Company Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Consolidation	Consolidation— The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany accounts and transactions have been eliminated.
Cash and Cash Equivalents	Cash and Cash Equivalents— The Company considers cash equivalents to be highly liquid investments with a maturity at the date of purchase of three months or less. The Company invests its cash equivalents primarily in money market funds with high quality institutions.
Accounts Receivable	Accounts Receivable— The Company sells its products directly to hospitals and reference laboratories as well as to distributors in the U.S. and sells directly to hospitals and labs and through distribution internationally (see Note 9 ). The Company periodically assesses the financial strength of these customers and establishes reserves for anticipated losses when necessary, which historically have not been material. The Company’s reserves primarily consist of amounts related to cash discounts and contract rebates. The balance of accounts receivable is net of reserves of $12.0 million and $12.3 million at December 31, 2018 and 2017 , respectively.
Concentration of Credit Risk	Concentration of Credit Risk— Financial instruments that potentially subject the Company to significant concentrations of credit risk consists principally of trade accounts receivable. The Company performs credit evaluations of its customers’ financial condition and limits the amount of credit extended when deemed necessary, but generally requires no collateral. Credit quality is monitored regularly by reviewing credit history. The Company believes that the concentration of credit risk in its trade accounts receivables is moderated by its credit evaluation process, relatively short collection terms, the high level of credit worthiness of its customers, and letters of credit issued on the Company’s behalf. Potential credit losses are limited to the gross value of accounts receivable.
Inventories	Inventories— Inventories are stated at the lower of cost (first-in, first-out) or net realizable value. The Company reviews the components of its inventory on a quarterly basis for excess, obsolete and impaired inventory and makes appropriate dispositions as obsolete stock is identified.
Property, Plant and Equipment	Property, Plant and Equipment— Property, plant and equipment is recorded at cost and depreciated over the estimated useful lives of the assets ( three to fifteen years) using the straight-line method. Amortization of leasehold improvements is computed on the straight-line method over the estimated useful lives of the assets.
Intangible Assets	Goodwill and Intangible Assets— Intangible assets are recorded at cost and amortized on a straight-line basis over their estimated useful lives, except for indefinite-lived intangibles such as goodwill. Software development costs associated with software to be leased or otherwise marketed are expensed as incurred until technological feasibility has been established. After technological feasibility is established, software development costs are capitalized. The capitalized cost is amortized on a straight-line basis over the estimated product life or on the ratio of current revenues to total projected product revenues, whichever is greater.
Convertible Debt	Convertible Debt— The Company accounts for convertible debt instruments that may be settled in cash upon conversion (including combination settlement of cash equal to the “principal portion” and delivery of the “share amount” in excess of the conversion value over the principal portion in shares of common stock and/or cash) by separating the liability and equity components of the instruments in a manner that reflects our nonconvertible debt borrowing rate. The Company determines the carrying amount of the liability component by measuring the fair value of similar debt instruments that do not have the conversion feature. If no similar debt instrument exists, the Company estimates fair value by using assumptions that market participants would use in pricing a debt instrument, including market interest rates, credit standing, yield curves and volatilities. Determining the fair value of the debt component requires the use of accounting estimates and assumptions. These estimates and assumptions are judgmental in nature and could have a significant impact on the determination of the debt component, and the associated non-cash interest expense. See Note 3 for additional discussion of the Convertible Senior Notes issued in December 2014.
Revenue Recognition	Revenue Recognition
Research and Development Costs	Research and Development Costs— Research and development costs are charged to operations as incurred. In conjunction with certain third-party service agreements, the Company is required to make periodic payments based on achievement of certain milestones. The costs related to these research and development services are also charged to operations as incurred.
Shipping and Handling Cost, Policy [Policy Text Block]	Product Shipment Costs— Product shipment costs are included in sales and marketing expense in the accompanying Consolidated Statements of Operations.
Advertising Costs	Advertising Costs— Advertising costs are expensed as incurred.
Deferred Rent	Deferred Rent— The Company enters into lease arrangements for office space under non-cancelable operating leases. Certain of the operating lease agreements contain rent escalation provisions, which are considered in determining the straight-line rent expense to be recorded over the lease term. The lease term begins on the date of initial possession of the leased property for purposes of recognizing lease expense on a straight-line basis over the term of the lease. The Company does not assume renewals in the determination of the lease term unless the renewals are deemed to be reasonably assured at lease inception. The difference between rent expense and amounts paid under the Company’s lease agreements are recorded as deferred rent.
Income Taxes	Income Taxes— Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes, using enacted tax rates in effect for the year in which the differences are expected to reverse. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized. The Company’s policy is to recognize the interest expense and penalties related to income tax matters as a component of the income tax provision.
Fair Value of Financial Instruments	Fair Value of Financial Instruments —
Product Warranty	Product Warranty —The Company generally sells products with a limited product warranty and certain limited indemnifications. Due to product testing, the short time between product shipment and the detection and correction of product failures and a low historical rate of payments on claims, the historical activity and the related expense were not significant for the fiscal years presented.
Stock-Based Compensation	Stock-Based Compensation —Compensation expense related to stock options granted is recognized ratably over the service vesting period for the entire option. For stock options with graded vesting, the Company ensures that the cumulative amount of compensation expense recognized at the end of any reporting period at least equals the portion of the stock option that has vested at that date. The total number of stock options expected to vest is adjusted by estimated forfeiture rates. The Company determined the estimated fair value of each stock option on the date of grant using the Black-Scholes option valuation model. The fair value of restricted stock units is determined based on the closing market price of the Company’s common stock on the grant date.
Comprehensive (Loss) Income	Comprehensive Income (loss) —Comprehensive income (loss) includes unrealized gains and losses which are related to the cumulative translation adjustments excluded from the Company’s Consolidated Statements of Operations.
Use of Estimates	Use of Estimates —The preparation of financial statements in conformity with accounting principles generally accepted in the U.S. requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures 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.
Accounting Periods	Accounting Periods —Each of the Company’s fiscal quarters end on the Sunday closest to the end of the calendar quarter. The Company’s fiscal year ends are December 30, 2018, December 31, 2017 and January 1, 2017. For ease of reference, the calendar quarter end dates are used herein.
Lessee, Operating Leases [Text Block]	In February 2016, the FASB issued guidance codified in ASU 2016-02 (Topic 842), Leases . The guidance requires a lessee to recognize a lease liability for the obligation to make lease payments and a right-of-use asset representing the right to use the underlying asset for the lease term on the balance sheet. Under ASU 2016-02, adoption was required on a modified retrospective transition basis for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. In July 2018, the FASB issued ASU 2018-11, which allows for an alternative method to adopt the lease standard by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption, with no adjustment to prior comparative periods. ASU 2016-02 and all subsequent amendments (collectively, “ASC 842”) are effective for public entities for annual reporting periods beginning after December 15, 2018, including interim periods therein. The Company will adopt ASC 842 on January 1, 2019 using the alternative method of adoption. We estimate that the impact of the adoption will be to add approximately $87.0 million in operating right-of-use assets; increase the current portion of operating lease liabilities and non-current operating lease liabilities by approximately $5.0 million and $85.0 million , respectively; and decrease current and non-current deferred rent by approximately $0.5 million and $2.5 million , respectively. There are no adjustments to retained earnings. In applying ASC 842, the Company will adopt the package of practical expedients which, among other things, allows the Company to carry forward its historical lease classification. Additionally, the Company will adopt a policy to exclude short-term leases from the calculation of the right-of-use assets and lease liabilities.
Recent Accounting Pronouncements	Recent Accounting Pronouncements —In May 2014, the Financial Accounting Standards Board (“FASB”) issued guidance codified in Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers , which amends the guidance in former ASC 605, Revenue Recognition (“ASU 2014-09”). The standard’s core principle is that a company will recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. In doing so, companies are required to use more judgment and make more estimates than under prior authoritative guidance. These may include identifying performance obligations in the contract, estimating the amount of variable consideration to include in the transaction price and allocating the transaction price to each separate performance obligation. The FASB has issued several amendments to the new standard, which include clarification of accounting guidance related to identification of performance obligations, intellectual property licenses and principal vs. agent considerations. ASU 2014-09 and all subsequent amendments (collectively, “ASC 606”) were effective for public entities for annual reporting periods beginning after December 15, 2017, including interim periods therein. The Company adopted ASC 606 on January 1, 2018, using the modified retrospective transition method applied to those contracts which were not completed as of that date. The cumulative effect of applying the new revenue standard to all incomplete contracts as of January 1, 2018 was not material and, therefore, did not result in an adjustment to opening retained earnings. The adoption of ASC 606 did not have a material impact on the Company’s consolidated financial position, results of operations, equity or cash flows as of the adoption date or for the year ended December 31, 2018 . In February 2016, the FASB issued guidance codified in ASU 2016-02 (Topic 842), Leases . The guidance requires a lessee to recognize a lease liability for the obligation to make lease payments and a right-of-use asset representing the right to use the underlying asset for the lease term on the balance sheet. Under ASU 2016-02, adoption was required on a modified retrospective transition basis for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. In July 2018, the FASB issued ASU 2018-11, which allows for an alternative method to adopt the lease standard by recognizing a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption, with no adjustment to prior comparative periods. ASU 2016-02 and all subsequent amendments (collectively, “ASC 842”) are effective for public entities for annual reporting periods beginning after December 15, 2018, including interim periods therein. The Company will adopt ASC 842 on January 1, 2019 using the alternative method of adoption. We estimate that the impact of the adoption will be to add approximately $87.0 million in operating right-of-use assets; increase the current portion of operating lease liabilities and non-current operating lease liabilities by approximately $5.0 million and $85.0 million , respectively; and decrease current and non-current deferred rent by approximately $0.5 million and $2.5 million , respectively. There are no adjustments to retained earnings. In applying ASC 842, the Company will adopt the package of practical expedients which, among other things, allows the Company to carry forward its historical lease classification. Additionally, the Company will adopt a policy to exclude short-term leases from the calculation of the right-of-use assets and lease liabilities. In January 2017, the FASB issued guidance codified in ASU 2017-04, Intangibles-Goodwill and Other (Topic 350) Simplifying the Test for Goodwill Impairment (“ASU 2017-04”). Under this new guidance, an entity will no longer determine goodwill impairment by calculating the implied fair value of goodwill by assigning the fair value of a reporting unit to all of its assets and liabilities as if that reporting unit had been acquired in a business combination. Instead, an entity will compare the fair value of a reporting unit with its carrying amount and recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value. The guidance is effective for fiscal years beginning after December 15, 2019 including interim periods therein. The Company is currently evaluating the impact of this guidance and expects to adopt the standard in the first quarter of 2020.

Earnings (Loss) Per Share Earni

Earnings (Loss) Per Share Earnings per share (Policies)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Earnings Per Share, Policy [Policy Text Block]	Basic earnings (loss) per share (“EPS”) is computed by dividing net income (loss) by the weighted-average number of common shares outstanding. Diluted EPS is computed based on the sum of the weighted average number of common shares and potentially dilutive common shares outstanding during the period. Potentially dilutive common shares consist of shares issuable from stock options, unvested RSUs and the 3.25% Convertible Senior Notes. Potentially dilutive common shares from outstanding stock options and unvested RSUs are determined using the average share price for each period under the treasury stock method. Potentially dilutive shares from the Convertible Senior Notes are determined using the if-converted method. Under the provisions of the if-converted method, the Convertible Senior Notes are assumed to be converted and the resulting commons shares are included in the denominator of the EPS calculation and the interest expense, net of tax, recorded in connection with the Convertible Senior Notes is added back to net income (loss). The Convertible Senior Notes have a dilutive impact when the average market price of the Company’s common stock exceeds the applicable conversion price of the notes. The Convertible Senior Notes became convertible on March 31, 2018 and remained convertible through December 31, 2018 .

Balance Sheet Account Details_2

Balance Sheet Account Details (Tables)	12 Months Ended
	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Schedule of Other Current Assets	Prepaid expenses and other current assets The following is a summary of prepaid expenses and other current assets (in thousands): December 31, 2018 2017 Receivables under transition service agreements $ 15,507 $ 7,509 Income taxes receivable 2,703 3,806 Prepaid expenses 4,508 2,898 Other 928 162 Total prepaid expenses and other current assets $ 23,646 $ 14,375
Summary of Inventories	December 31, 2018 2017 Raw materials $ 24,292 $ 22,252 Work-in-process (materials, labor and overhead) 21,280 22,813 Finished goods (materials, labor and overhead) 21,807 22,013 Total inventories $ 67,379 $ 67,078
Property, Plant and Equipment	The following is a summary of property, plant and equipment (in thousands): December 31, 2018 2017 Equipment, furniture and fixtures $ 89,285 $ 75,728 Building and improvements 37,335 34,994 Leased instruments 42,647 32,458 Land 1,080 1,080 Total property, plant and equipment, gross 170,347 144,260 Less: accumulated depreciation and amortization (96,446 ) (82,675 ) Total property, plant and equipment, net $ 73,901 $ 61,585
Summary of Intangible Assets	Amortizable intangible assets consisted of the following (dollar amounts in thousands): December 31, 2018 December 31, 2017 Description Weighted-average useful life (years) Gross assets Accumulated amortization Net Gross assets Accumulated amortization Net Purchased technology 9.1 $ 112,100 $ (57,495 ) $ 54,605 $ 112,100 $ (49,614 ) $ 62,486 Customer relationships 7.0 122,389 (27,561 ) 94,828 122,404 (10,960 ) 111,444 License agreements 9.9 6,511 (4,530 ) 1,981 6,515 (3,980 ) 2,535 Patent and trademark costs 10.8 28,740 (7,624 ) 21,116 28,740 (4,917 ) 23,823 Software development costs 5.0 6,629 (4,130 ) 2,499 6,630 (3,091 ) 3,539 Total amortizable intangible assets $ 276,369 $ (101,340 ) $ 175,029 $ 276,389 $ (72,562 ) $ 203,827
Summary of Expected Future Annual Amortization Expense	The expected future annual amortization expense of the Company’s intangible assets is as follows (in thousands): For the years ending December 31, Amortization expense 2019 $ 27,542 2020 27,144 2021 26,999 2022 26,468 2023 25,758 Thereafter 41,118 Total $ 175,029
Schedule of Other Current Liabilities	The following is a summary of other current liabilities (in thousands): December 31, 2018 2017 Customer incentives $ 7,516 $ 7,165 Accrued interest 347 442 Other 5,129 5,059 Total other current liabilities $ 12,992 $ 12,666

Debt Tables (Tables)

Debt Tables (Tables)	12 Months Ended
	Dec. 31, 2018
Debt Disclosure [Abstract]
Schedule of Extinguishment of Debt [Table Text Block]	The following table summarizes information about the settlement of the Convertible Senior Notes (in thousands): Year ended December 30, 2018 Principal amount settled $ 108,811 Number of shares of common stock issued 3,699 Loss on extinguishment of debt $ 2,303
Schedule of Long-term Debt Instruments	The following table summarizes information about the equity and liability components of the Convertible Senior Notes (dollars in thousands). The fair values of the respective notes outstanding were measured based on quoted market prices: December 31, 2018 2017 Principal amount of Convertible Senior Notes outstanding $ 58,503 $ 167,314 Unamortized discount of liability component (3,637 ) (15,356 ) Unamortized deferred issuance costs (487 ) (2,090 ) Net carrying amount of liability component 54,379 149,868 Less: current portion 54,379 — Long-term debt $ — $ 149,868 Carrying value of equity component, net of issuance costs $ 10,092 $ 29,211 Fair value of outstanding Convertible Senior Notes $ 85,999 $ 257,245 Remaining amortization period of discount on the liability component 2 years 3 years

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Components of (Benefit) Provision for Income Taxes	Significant components of the (benefit) provision for income taxes are as follows (in thousands): December 31, 2018 2017 2016 Current: Federal $ — $ (615 ) $ (117 ) State 755 314 246 Foreign 6,575 57 84 Total current provision (benefit) 7,330 (244 ) 213 Deferred: Federal (9,970 ) 131 (2,545 ) State (7,944 ) 238 (63 ) Foreign (215 ) 4 4 Total deferred (benefit) provision (18,129 ) 373 (2,604 ) (Benefit) provision for income taxes $ (10,799 ) $ 129 $ (2,391 )
Schedule of Income before (Benefit) Provision for Income Taxes	The Company’s income (loss) before income taxes was subject to taxes in the following jurisdictions for the following periods (in thousands): December 31, 2018 2017 2016 United States $ 46,592 $ (8,198 ) $ (16,426 ) Foreign 16,792 162 227 Income (loss) before income taxes $ 63,384 $ (8,036 ) $ (16,199 )
Schedule of Deferred Tax Assets and Liabilities	Significant components of the Company’s deferred tax assets and deferred tax liabilities as of December 31, 2018 and 2017 are shown below (in thousands): December 31, 2018 2017 Deferred tax assets: Net operating loss carryforwards $ 711 $ 3,924 Intangible assets 3,502 2,935 Sale-leaseback, net 617 628 Allowance for returns and discounts 4,541 5,358 Stock-based compensation 5,333 5,933 Tax credit carryforwards 12,246 5,247 Other, net 6,883 4,580 Total deferred tax assets 33,833 28,605 Valuation allowance for deferred tax assets (1,830 ) (15,204 ) Total deferred tax assets, net of valuation allowance 32,003 13,401 Deferred tax liabilities: Convertible Senior Notes (636 ) (3,633 ) Intangible assets (2,165 ) (2,935 ) Property, plant and equipment (7,010 ) (7,263 ) Total deferred tax liabilities (9,811 ) (13,831 ) Net deferred tax assets (liabilities) $ 22,192 $ (430 )
Reconciliation of Income Tax Computed at Federal Statutory Rate	Year ended December 31, 2018 2017 2016 Tax expense (benefit) at statutory tax rate $ 13,311 $ (2,812 ) $ (5,775 ) State tax (benefits), net of federal tax 1,526 (239 ) (390 ) Permanent differences 635 327 129 Federal and state research credits—current year (3,628 ) (484 ) (979 ) Accrual of uncertain tax positions — 142 43 Stock-based compensation (9,286 ) (5,851 ) — Impact of change in federal and state tax rate on revaluing deferred tax assets — 3,357 (4 ) Change in valuation allowance (13,374 ) 5,799 4,687 Foreign Derived Intangible Income Deduction (FDII) (786 ) — — Other 803 (110 ) (102 ) (Benefit) provision for income taxes $ (10,799 ) $ 129 $ (2,391 )
Summary of Unrecognized Tax Benefits	The following table summarizes the activity related to the Company’s unrecognized tax benefits (in thousands): Year ended December 31, 2018 2017 2016 Beginning balance $ 9,565 $ 8,604 $ 7,684 (Decreases) increases related to prior year tax positions (558 ) 10 (10 ) Increases related to current year tax positions 6,238 951 773 Other — — 157 Ending balance $ 15,245 $ 9,565 $ 8,604

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation Expense Related to Stock-Based Compensation Plans	Stock-based compensation expense related to stock options and restricted stock units was as follows (in thousands): Year ended December 31, 2018 2017 2016 Cost of sales $ 763 $ 579 $ 617 Research and development 2,266 1,886 1,551 Sales and marketing 2,843 2,129 1,189 General and administrative 5,837 4,467 4,629 Total stock-based compensation expense $ 11,709 $ 9,061 $ 7,986
Estimated Fair Value of Each Stock Option Award	The estimated fair value of each stock option was determined on the date of grant using the Black-Scholes option valuation model with the following weighted-average assumptions: Year ended December 31, 2018 2017 2016 Risk-free interest rate 2.49 % 2.30 % 1.47 % Expected option life (in years) 6.29 6.63 6.59 Volatility rate 36 % 36 % 36 % Dividend rate — % — % — %
Summary of Status of Stock Option Activity	A summary of the status of stock option activity for the years ended December 31, 2016 , 2017 and 2018 is as follows (in thousands, except price data and years): Number of Shares Weighted- average exercise price per share Weighted- average remaining contractual term (in years) Aggregate intrinsic value Outstanding at January 1, 2016 3,967 $ 17.44 Granted 677 15.48 Exercised (553 ) 13.76 Cancelled (150 ) 20.86 Outstanding at December 31, 2016 3,941 17.49 Granted 263 22.21 Exercised (1,527 ) 16.38 Cancelled (18 ) 24.91 Outstanding at December 31, 2017 2,659 18.54 Granted 159 46.50 Exercised (891 ) 17.07 Cancelled (50 ) 21.19 Outstanding at December 31, 2018 1,877 $ 21.53 5.98 $ 49,976 Vested and expected to vest at December 31, 2018 1,838 $ 21.34 5.93 $ 49,302 Exercisable at December 31, 2018 1,117 $ 19.28 4.83 $ 32,374
Summary of Status of Stock Awards Activity	A summary of the status of restricted stock unit activity for the years ended December 31, 2016 , 2017 and 2018 is as follows (in thousands, except price data): Shares Weighted-average grant date fair value Non-vested at January 1, 2016 459 $ 21.61 Granted 185 16.14 Vested (120 ) 18.50 Forfeited (23 ) 20.80 Non-vested at December 31, 2016 501 20.37 Granted 349 22.34 Vested (100 ) 23.49 Forfeited (4 ) 18.69 Non-vested at December 31, 2017 746 20.88 Granted 242 49.97 Vested (296 ) 21.70 Forfeited (16 ) 28.40 Non-vested at December 31, 2018 676 $ 30.75

Earnings (Loss) Per Share (Tabl

Earnings (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]	The following table reconciles net income (loss) and the weighted-average shares used in computing basic and diluted earnings per share in the respective periods (in thousands): Twelve months ended December 31, 2018 2017 2016 Numerator: Net income (loss) used for basic earnings per share $ 74,183 $ (8,165 ) $ (13,808 ) Interest expense on Convertible Senior Notes, net of tax 4,927 — — Net income (loss) used for diluted earnings per share, if-converted method $ 79,110 $ (8,165 ) $ (13,808 ) Basic weighted-average common shares outstanding 37,995 33,734 32,708 Potentially dilutive shares issuable from Convertible Senior Notes, if-converted 2,850 — — Potentially dilutive shares issuable from stock options and unvested RSUs 1,709 — — Diluted weighted-average common shares outstanding, if-converted 42,554 33,734 32,708 Potentially dilutive shares excluded from calculation due to anti-dilutive effect 161 37 2,770
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table reconciles net income (loss) and the weighted-average shares used in computing basic and diluted earnings per share in the respective periods (in thousands): Twelve months ended December 31, 2018 2017 2016 Numerator: Net income (loss) used for basic earnings per share $ 74,183 $ (8,165 ) $ (13,808 ) Interest expense on Convertible Senior Notes, net of tax 4,927 — — Net income (loss) used for diluted earnings per share, if-converted method $ 79,110 $ (8,165 ) $ (13,808 ) Basic weighted-average common shares outstanding 37,995 33,734 32,708 Potentially dilutive shares issuable from Convertible Senior Notes, if-converted 2,850 — — Potentially dilutive shares issuable from stock options and unvested RSUs 1,709 — — Diluted weighted-average common shares outstanding, if-converted 42,554 33,734 32,708 Potentially dilutive shares excluded from calculation due to anti-dilutive effect 161 37 2,770

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments for Minimum Rentals under Non-cancelable Leases	The Company leases its facilities and certain equipment. Commitments for minimum rentals under non-cancelable leases at the end of 2018 are as follows (in thousands): Years ending December 31, Operating Leases Lease obligation 2019 $ 9,940 $ 956 2020 10,601 967 2021 10,502 — 2022 8,965 — 2023 8,409 — Thereafter 86,797 — Total minimum lease payments $ 135,214 $ 1,923

Industry and Geographic Infor_2

Industry and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Sales to Individual Customers in Excess of 10% of Total Revenue	The Company had sales to individual customers in excess of 10% of total revenue, as follows: Year ended December 31, 2018 2017 2016 Customer: A 19 % 20 % 15 % B 13 % 13 % 13 % C 12 % 21 % 16 % 44 % 54 % 44 %
Long-Lived Assets (Excluding Intangible Assets) and Total Net Revenue	The following presents long-lived assets (excluding intangible assets) and total net revenue by geographic territory (in thousands): Long-lived assets as of December 31, Total revenue for the years ended December 31, 2018 2017 2018 2017 2016 Domestic $ 72,569 $ 59,833 $ 354,895 $ 227,611 $ 158,244 Foreign 1,332 1,752 167,390 50,132 33,359 Total $ 73,901 $ 61,585 $ 522,285 $ 277,743 $ 191,603
Consolidated Net Product Revenues by Disease State	Consolidated net revenues by product category are as follows (in thousands): Year ended December 31, 2018 2017 2016 Rapid Immunoassay $ 183,160 $ 165,099 $ 121,416 Cardiac Immunoassay 266,524 47,030 — Specialized Diagnostic Solutions 53,243 51,978 60,681 Molecular Diagnostic Solutions 19,358 13,636 9,506 Total revenues $ 522,285 $ 277,743 $ 191,603

Fair Value Measurement (Tables)

Fair Value Measurement (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table presents the Company’s hierarchy for its assets and liabilities measured at fair value on a recurring basis as of the following periods (in thousands): December 31, 2018 December 31, 2017 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Contingent consideration $ — $ — $ 19,112 $ 19,112 $ — $ — $ 24,301 $ 24,301 Deferred consideration — 187,158 — 187,158 — 223,158 — 223,158 Total liabilities measured at fair value $ — $ 187,158 $ 19,112 $ 206,270 $ — $ 223,158 $ 24,301 $ 247,459
Changes in Estimated Fair Value of Contingent Consideration Liabilities	Changes in estimated fair value of contingent consideration liabilities from December 31, 2017 through December 31, 2018 are as follows (in thousands): Contingent consideration liability (Level 3 measurement) Balance at December 31, 2017 $ 24,301 Cash payments (6,303 ) Net loss recorded for fair value adjustments 1,114 Balance at December 31, 2018 $ 19,112

Acquisition (Tables)

Acquisition (Tables)	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Business Acquisition	The purchase price consideration is as follows (in thousands): Cash consideration—Triage Business $ 399,798 Deferred consideration—BNP Business 220,550 Contingent consideration—BNP Business 19,700 Inventory related adjustment 205 Net consideration $ 640,253
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed	Prepaid expenses and other current assets $ 796 Assets held for sale 146,540 Inventories 52,205 Property, plant and equipment 10,608 Intangible assets 184,900 Goodwill 245,531 Other non-current assets 182 Total assets acquired 640,762 Other current liabilities (509 ) Total net assets and liabilities acquired $ 640,253
Finite-Lived Intangible Assets Acquired as Part of Business Combination	The following sets forth results of the amounts assigned to the identifiable intangible assets acquired (in thousands): Intangible Asset Amortization period Fair value of assets acquired Purchased technology 10 years $ 52,400 Customer relationships 7 years 115,000 Trademarks 10 years 17,500 Total intangible assets $ 184,900

Selected Quarterly Financial _2

Selected Quarterly Financial Data (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data	First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share data) 2018 Total revenues $ 169,143 $ 103,155 $ 117,399 $ 132,588 Gross profit $ 106,271 $ 57,668 $ 69,642 $ 82,132 Operating income (loss) $ 51,093 $ 404 $ 16,894 $ 27,538 Net income (loss) $ 33,958 $ (3,076 ) $ 10,822 $ 32,479 Basic income (loss) per share $ 0.96 $ (0.08 ) $ 0.28 $ 0.82 Diluted income (loss) per share $ 0.86 $ (0.08 ) $ 0.27 $ 0.78 2017 Total revenues $ 73,692 $ 38,267 $ 50,894 $ 114,890 Gross profit (1) $ 48,499 $ 18,826 $ 29,690 $ 59,127 Operating income (loss) $ 19,229 $ (11,027 ) $ (2,537 ) $ 3,887 Net income (loss) $ 14,290 $ (11,842 ) $ (5,525 ) $ (5,088 ) Basic income (loss) per share $ 0.43 $ (0.35 ) $ (0.16 ) $ (0.15 ) Diluted income (loss) per share $ 0.42 $ (0.35 ) $ (0.16 ) $ (0.15 ) First Quarter Second Quarter Third Quarter Fourth Quarter (in thousands, except per share data) 2018 Total revenues $ 169,143 $ 103,155 $ 117,399 $ 132,588 Gross profit $ 106,271 $ 57,668 $ 69,642 $ 82,132 Operating income (loss) $ 51,093 $ 404 $ 16,894 $ 27,538 Net income (loss) $ 33,958 $ (3,076 ) $ 10,822 $ 32,479 Basic income (loss) per share $ 0.96 $ (0.08 ) $ 0.28 $ 0.82 Diluted income (loss) per share $ 0.86 $ (0.08 ) $ 0.27 $ 0.78 2017 Total revenues $ 73,692 $ 38,267 $ 50,894 $ 114,890 Gross profit (1) $ 48,499 $ 18,826 $ 29,690 $ 59,127 Operating income (loss) $ 19,229 $ (11,027 ) $ (2,537 ) $ 3,887 Net income (loss) $ 14,290 $ (11,842 ) $ (5,525 ) $ (5,088 ) Basic income (loss) per share $ 0.43 $ (0.35 ) $ (0.16 ) $ (0.15 ) Diluted income (loss) per share $ 0.42 $ (0.35 ) $ (0.16 ) $ (0.15 )

Company Operations and Summar_3

Company Operations and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2016USD ($)	Dec. 31, 2018USD ($)segment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of business segment | segment		1
Cash and cash equivalents maximum maturity period		3 months
Account receivable, reserves		$ 12,000	$ 12,300
Revenues		522,285	277,743	$ 191,603
Costs and Expenses		219,784	146,590	116,170
Advertising cost expensed	$ 300	900	500
Operating Lease, Right-of-Use Asset		87,000
Operating Lease, Liability, Current		5,000
Operating Lease, Liability, Noncurrent		85,000
Deferred Rent Credit, Current		500
Deferred rent		$ 2,500
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful lives of the assets		3 years
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Estimated useful lives of the assets		15 years
Grant [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues		$ 0		6,500
Shipping and Handling [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Costs and Expenses		$ 8,300	$ 3,700	$ 3,800

Balance Sheet Account Details

Balance Sheet Account Details - Prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Offsetting [Abstract]
Receivables under transition service agreements	$ 15,507	$ 7,509
Income taxes receivable	2,703	3,806
Prepaid expenses	4,508	2,898
Other	928	162
Prepaid expenses and other current assets	$ 23,646	$ 14,375

Balance Sheet Account Details_3

Balance Sheet Account Details - Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 24,292	$ 22,252
Work-in-process (materials, labor and overhead)	21,280	22,813
Finished goods (materials, labor and overhead)	21,807	22,013
Total inventories	$ 67,379	$ 67,078

Balance Sheet Account Details_4

Balance Sheet Account Details - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 170,347	$ 144,260
Less: accumulated depreciation and amortization	96,446	82,675
Property, Plant and Equipment, Net	73,901	61,585
Depreciation and amortization	17,700	14,600	$ 13,400
Equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	89,285	75,728
Building and improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	37,335	34,994
Leased instruments
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	42,647	32,458
Land
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 1,080	$ 1,080

Balance Sheet Account Details_5

Balance Sheet Account Details - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance Sheet Related Disclosures [Abstract]
Depreciation and amortization	$ 17,700	$ 14,600	$ 13,400
Amortization of Intangible Assets	28,800	16,100	$ 9,500
Goodwill	$ 337,021	$ 337,028

Balance Sheet Account Details -

Balance Sheet Account Details - Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 28,800	$ 16,100	$ 9,500
Goodwill	337,021	337,028
Gross assets	276,369	276,389
Accumulated amortization	(101,340)	(72,562)
Total	175,029	203,827
Capitalized Software Cost [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 1,000	800	$ 500
Purchased technology
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful life (years)	9 years 1 month
Gross assets	$ 112,100	112,100
Accumulated amortization	(57,495)	(49,614)
Total	$ 54,605	62,486
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful life (years)	7 years 10 days
Gross assets	$ 122,389	122,404
Accumulated amortization	(27,561)	(10,960)
Total	$ 94,828	111,444
License agreements
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful life (years)	9 years 10 months 10 days
Gross assets	$ 6,511	6,515
Accumulated amortization	(4,530)	(3,980)
Total	$ 1,981	2,535
Patent and trademark costs
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful life (years)	10 years 9 months
Gross assets	$ 28,740	28,740
Accumulated amortization	(7,624)	(4,917)
Total	$ 21,116	23,823
Software development costs
Finite-Lived Intangible Assets [Line Items]
Weighted-average useful life (years)	5 years
Gross assets	$ 6,629	6,630
Accumulated amortization	(4,130)	(3,091)
Total	$ 2,499	$ 3,539

Balance Sheet Account Details_6

Balance Sheet Account Details - Future annual amortization expense (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Balance Sheet Related Disclosures [Abstract]
2,018	$ 27,542
2,019	27,144
2,020	26,999
2,021	26,468
2,022	25,758
Thereafter	41,118
Total	$ 175,029	$ 203,827

Balance Sheet Account Details_7

Balance Sheet Account Details - Other current liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Offsetting [Abstract]
Customer incentives	$ 7,516	$ 7,165
Accrued interest	347	442
Other	5,129	5,059
Total other current liabilities	$ 12,992	$ 12,666

Debt Convertible Senior Notes (

Debt Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2018USD ($)d	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2016USD ($)	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Interest expense, Convertible Senior Notes, Amortization		$ 5,500
Interest Expense, Debt	$ 5,700	10,900	$ 10,900
Debt Instrument, Convertible, If-converted Value in Excess of Principal	1,600
Convertible Debt [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Carrying value of equity component, net of issuance costs	10,092	29,211
Convertible Debt [Member] | Other Current Assets [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Deferred financing costs	$ 487	$ 2,090
3.25% Convertible Senior Notes due 2020 [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Convertible Senior Notes, face amount				$ 172,500
Senior Credit Facility, applicable margin	3.25%			3.25%
Debt issuance cost				$ 5,100
Deferred financing costs				$ 4,200
Remaining amortization period of discount on the liability component				6 years
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs				$ 900
Convertible Senior Notes, conversion ratio	31.1891
Convertible Senior Notes, conversion price (in dollars per share) | $ / shares		$ 32.06
Convertible Senior Notes, threshold trading days | d	20
Convertible Senior Notes, threshold consecutive trading days | d	30
Convertible Senior Notes, threshold percentage of stock price trigger	130.00%
Convertible Senior Notes, threshold consecutive business days	5 years
Debt Instrument, Convertible, Threshold Consecutive Trading Days, Following Consecutive Business Days	5 years
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger, Following Consecutive Business Days	98.00%
Convertible Senior Notes, observation period	25 years
Debt Instrument, Interest Rate, Effective Percentage		6.60%		6.90%
Interest expense, Convertible Senior Notes, Amortization	$ 3,100		5,400
Interest Expense, Debt	6,100
Interest expense, Convertible Senior Notes	$ 3,000	$ 5,400	$ 5,500
Debt Conversion, Converted Instrument, Rate	100.00%
Convertible Senior Notes, fair value disclosures				$ 141,900
Proceeds from issuance				172,500
Carrying value of equity component, net of issuance costs				$ 30,700
Convertible Debt [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Extinguishment of Debt, Amount	$ 108,811

Debt Debt schedule (Details)

Debt Debt schedule (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2014
Debt Instrument [Line Items]
Less: current portion	$ 0	$ 10,184
Long-term debt	0	227,394
Convertible Debt [Member] | 3.25% Convertible Senior Notes due 2020 [Member]
Debt Instrument [Line Items]
Unamortized deferred issuance costs			$ (4,200)
Carrying value of equity component, net of issuance costs			$ 30,700
Convertible Debt [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Principal amount of Convertible Senior Notes outstanding	58,503	167,314
Unamortized deferred issuance costs	(3,637)	(15,356)
Net carrying amount of liability component	54,379	149,868
Less: current portion	54,379	0
Long-term debt	0	149,868
Carrying value of equity component, net of issuance costs	10,092	29,211
Fair value of outstanding Convertible Senior Notes	$ 85,999	$ 257,245
Remaining amortization period of discount on the liability component	2 years	3 years
Other Current Assets [Member] | Convertible Debt [Member] | Convertible Debt [Member]
Debt Instrument [Line Items]
Unamortized deferred issuance costs	$ (487)	$ (2,090)

Extinguishemnt of Debt (Detail)

Extinguishemnt of Debt (Detail) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Extinguishment of Debt [Line Items]
Loss (gain) on extinguishment of debt	$ 8,262	$ 0	$ (421)
Convertible Debt [Member]
Extinguishment of Debt [Line Items]
Number of shares of common stock issued	3,699
Loss (gain) on extinguishment of debt	$ 2,303
Convertible Debt [Member] | Convertible Debt [Member]
Extinguishment of Debt [Line Items]
Principal amount settled	$ 108,811

Debt Credit Agreement (Details)

Debt Credit Agreement (Details)	Aug. 31, 2018USD ($)	Oct. 06, 2017USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2018USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
Secured Debt		$ 245,000,000
Line of Credit Facility, Maximum Borrowing Capacity	$ 175,000,000	25,000,000
Revolving Credit Facility	$ 83,200,000				$ 53,188,000	$ 0
Repayments of Lines of Credit			$ 30,000,000	$ 10,000,000	40,000,000
Proceeds from issuance of Revolving Credit Facility		$ 10,000,000			0	10,000,000	$ 0
(Loss) gain on extinguishment of debt					(8,262,000)	0	421,000
Line of Credit Facility, Commitment Fee Percentage	0.15%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.30%
Number Of Financial Covenants	2
Consolidated Leverage Ratio	3.50
Consolidated Fixed Charge Coverage Ratio	1.25
Repayments of Debt					161,813,000
Interest Expense, Debt					5,700,000	$ 10,900,000	$ 10,900,000
Amortization of Debt Issuance Costs					$ 800,000
Federal Funds Effective Swap Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					0.005%
Base Rate [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	1.00%
London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	2.00%
Minimum [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	0.75%
Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	1.75%
Maximum [Member]
Debt Instrument [Line Items]
Consolidated Leverage Ratio	4.50
Maximum [Member] | Base Rate [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	1.50%
Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Senior Credit Facility, applicable margin	2.50%
Term Loan [Member]
Debt Instrument [Line Items]
(Loss) gain on extinguishment of debt					$ 6,000,000

Income Taxes - Components of (B

Income Taxes - Components of (Benefit) Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current:
Federal	$ 0	$ (615)	$ (117)
State	755	314	246
Foreign	6,575	57	84
Total current provision (benefit)	7,330	(244)	213
Deferred:
Federal	(9,970)	131	(2,545)
State	(7,944)	238	(63)
Foreign	(215)	4	4
Total deferred (benefit) provision	(18,129)	373	(2,604)
(Benefit) provision for income taxes	$ (10,799)	$ 129	$ (2,391)

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income before (Benefit) Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
United States	$ 46,592	$ (8,198)	$ (16,426)
Foreign	16,792	162	227
Income (loss) before income taxes	$ 63,384	$ (8,036)	$ (16,199)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 711	$ 3,924
Intangible assets	3,502	2,935
Sale-leaseback, net	617	628
Allowance for returns and discounts	4,541	5,358
Stock-based compensation	5,333	5,933
Tax credit carryforwards	12,246	5,247
Other, net	6,883	4,580
Total deferred tax assets	33,833	28,605
Valuation allowance for deferred tax assets	(1,830)	(15,204)
Total deferred tax assets	32,003	13,401
Deferred tax liabilities:
Convertible Senior Notes	(636)	(3,633)
Intangible assets	(2,165)	(2,935)
Property, plant and equipment	(7,010)	(7,263)
Deferred Tax Liabilities, Gross	(9,811)	(13,831)
Total deferred tax liabilities		$ (430)
Deferred Tax Assets, Net	$ 22,192

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Income Taxes Disclosure [Line Items]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 13,400,000
Deferred Tax Assets, Valuation Allowance	1,830,000	$ 15,204,000
Unrecognized Tax Benefits	15,245,000	9,565,000	$ 8,604,000	$ 7,684,000
Federal Net Operating Loss carryforwards	0
State Net Operating Loss carryforwards	19,300,000
Federal foreign tax credits	2,400,000
Gross research credits	$ 3,628,000	484,000	$ 979,000
Cumulative changes in ownership percentage	50.00%
Cumulative changes in ownership period	3 years
Realized upon settlement	50.00%
Unrecognized tax benefits that would impact effective tax rate	$ (9,300,000)	(8,100,000)
Accrued interest and penalties associated with uncertain tax positions	300,000
Interest expense, net of accrued interest reversed	100,000	$ 100,000
Federal research credits [Member]
Income Taxes Disclosure [Line Items]
Federal research credits	5,800,000
Gross State Research Credits [Member]
Income Taxes Disclosure [Line Items]
Gross research credits	12,800,000
State research credit - no expiry	12,400,000
State research credit - with expiry	$ 400,000

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Tax Computed at Federal Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax expense (benefit) at statutory tax rate	$ 13,311	$ (2,812)	$ (5,775)
State tax (benefits), net of federal tax	1,526	(239)	(390)
Permanent differences	635	327	129
Federal and state research credits—current year	(3,628)	(484)	(979)
Accrual of uncertain tax positions	0	142	43
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount	(9,286)	(5,851)	0
Impact of change in federal and state tax rate on revaluing deferred tax assets	0	3,357	(4)
Change in valuation allowance	(13,374)	5,799	4,687
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount	(786)
Other	803	(110)	(102)
(Benefit) provision for income taxes	$ (10,799)	$ 129	$ (2,391)

Income Taxes - Summary of Unrec

Income Taxes - Summary of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance		$ 9,565	$ 8,604
(Decreases) increases related to prior year tax positions	$ 10	558	10
Increases related to current year tax positions	773	6,238	951
Other	157	0	0
Ending balance	$ 8,604	$ 15,245	$ 9,565

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	Apr. 23, 2013	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 12, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Bonus Liability			$ 900	$ 500
Preferred stock, shares authorized		5,000,000	5,000,000	5,000,000
Preferred stock, shares outstanding			0	0
Weighted- average remaining contractual term, exercisable (in years)		4 years 9 months 29 days
Available for future grant, (in shares)		3,200,000
Restricted stock granted (in shares)		242,000	349,000	185,000
Share-based compensation expense recognized		$ 11,709	$ 9,061	$ 7,986
Deferred period of grants (Condition 1)		1 year
Percentage of premium on amount deferred (Condition 1)		10.00%
Deferred period of grants (Condition 2)		2 years
Percentage of premium on amount deferred (Condition 2)		20.00%
Deferred period of grants (Condition 3)		4 years
Percentage of premium on amount deferred (Condition 3)		30.00%
Minimum percentage of common stock under payroll deductions		10.00%
Fair value of payroll deductions		85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Period		6 years
Stock sold under the plan (in shares)		1,321,456
Capital shares reserved for future issuance (In shares)		178,544
Payments for repurchase of common stock		$ 4,344	541	20,168
Stock-based compensation expense		4,344	$ 541	$ 20,168
Authorized stock repurchase program amount					$ 50,000
Stock repurchase program remaining amount		$ 50,000
Common stock reserved for future issuance		5,700,000
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted- average remaining contractual term, exercisable (in years)		10 years
Performance-based vesting period		4 years
Restricted stock granted (in shares)		200,000	300,000	700,000
Share-based compensation expense recognized		$ 6,700	$ 4,900	$ 2,400
Employee Deferred Bonus Compensation Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized		$ 1,600	100	900
2010 Plan [Member] | Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance-based vesting period		1 year
Non-employee director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized		$ 400	$ 100	$ 400
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price (in usd per share)		$ 10.25
Percentage of deferred cash bonus		50.00%
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price (in usd per share)		$ 53.27
Percentage of deferred cash bonus		100.00%
Share Repurchase Program, Amendment [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for repurchase of common stock	$ 50,000
Repurchase of available shares under share repurchase program (in shares)			1,152,386
Stock-based compensation expense			$ 19,600
Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for purchase under ESPP (in shares)		178,544

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares 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]
Share-based compensation expense recognized	$ 11,709	$ 9,061	$ 7,986
Weighted-average grant date fair value of stock options granted (in dollars per share)	$ 18.76	$ 8.99	$ 6
Total intrinsic value for options exercised	$ 38,200	$ 26,800	$ 4,500
Total unrecognized compensation expense related to non-vested stock options	$ 4,400
Expected weighted-average period of recognition for unrecognized compensation expense	1 year 8 months 12 days
Maximum contractual term	10 years
Deferred Bonus Liability		900	500
Deferred bonus compensation program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized	$ 1,600	100	900
Recorded as a component of accrued payroll and related expenses	1,600	900
Stock options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized	3,400	4,100	4,700
Restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense recognized	$ 6,700	$ 4,900	$ 2,400
Number of restricted share units issued (in shares)	0.1
Total unrecognized compensation expense related to non-vested stock awards	$ 12,100

Stock-Based Compensation - Comp

Stock-Based Compensation - Compensation Expense Related to Stock-Based Compensation Plans (Detail) - 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]
Stock-based compensation expense	$ 11,709	$ 9,061	$ 7,986
Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	763	579	617
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	2,266	1,886	1,551
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	2,843	2,129	1,189
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 5,837	$ 4,467	$ 4,629

Stock-Based Compensation - Esti

Stock-Based Compensation - Estimated Fair Value of Each Stock Option Award (Detail)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity [Abstract]
Risk-free interest rate	2.49%	2.30%	1.47%
Expected option life (in years)	6 years 3 months 14 days	6 years 7 months 16 days	6 years 7 months 3 days
Volatility rate	36.00%	36.00%	36.00%
Dividend rate	0.00%	0.00%	0.00%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Status of Stock Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance, (in shares)	2,659	3,941	3,967
Granted, number of shares (in shares)	159	263	677
Exercised (in shares)	(891)	(1,527)	(553)
Cancelled (in shares)	(50)	(18)	(150)
Ending balance, (in shares)	1,877	2,659	3,941
Exercisable, (in shares)	1,117
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Rollforward]
Beginning balance, weighted average exercise price per share (in dollars per share)	$ 18.54	$ 17.49	$ 17.44
Granted, weighted average exercise price per share (in dollars per share)	46.50	22.21	15.48
Exercised, weighted average exercise price per share (in dollars per share)	17.07	16.38	13.76
Cancelled, weighted average exercise price per share (in dollars per share)	$ 21.19	24.91	20.86
Vested and expected to vest, (in shares)	1,838
Vested and expected to vest (in dollars per share)	$ 21.34
Exercisable (in usd per share)	19.28
Ending balance, weighted average exercise price per share (in dollars per share)	$ 21.53	$ 18.54	$ 17.49
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted- average remaining contractual term, outstanding (in years)	5 years 11 months 23 days
Weighted- average remaining contractual term, vested and expected to vest (in years)	5 years 11 months 6 days
Weighted- average remaining contractual term, exercisable (in years)	4 years 9 months 29 days
Aggregate intrinsic value, outstanding	$ 49,976
Aggregate intrinsic value, vested and expected to vest	49,302
Aggregate intrinsic value, available for future grant	$ 32,374

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Status of Stock Awards Activity (Detail) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Beginning Balance (in shares)	746	501	459
Granted (in shares)	242	349	185
Vested (in shares)	(296)	(100)	(120)
Forfeited (in shares)	(16)	(4)	(23)
Ending Balance (in shares)	676	746	501
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Rollforward]
Beginning Balance, Weighted Average Grant Date Fair Value (in dollars per share)	$ 20.88	$ 20.37	$ 21.61
Granted, Weighted Average Grant Date Fair Value (in dollars per share)	49,970	22.34	16.14
Vested, Weighted Average Grant Date Fair Value (in dollars per share)	21,700	23.49	18.50
Forfeited, Weighted Average Grant Date Fair Value (in dollars per share)	28,400	18.69	20.80
Ending Balance, Weighted Average Grant Date Fair Value (in dollars per share)	$ 30,750	$ 20.88	$ 20.37

Earnings (Loss) Per Share Compu

Earnings (Loss) Per Share Computation of earnings per share (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, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share Reconciliation [Abstract]
Net Income (Loss) Attributable to Parent	$ 32,479	$ 10,822	$ (3,076)	$ 33,958	$ (5,088)	$ (5,525)	$ (11,842)	$ 14,290	$ 74,183	$ (8,165)	$ (13,808)
Dilutive Securities, Effect on Basic Earnings Per Share, Dilutive Convertible Securities									4,927	0	0
Net Income (Loss) Available to Common Stockholders, Diluted									$ 79,110	$ (8,165)	$ (13,808)

Earnings (Loss) Per Share Weigh

Earnings (Loss) Per Share Weighted-average shares outstanding (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Basic weighted-average common shares outstanding	37,995	33,734	32,708
Potentially dilutive shares issuable from Convertible Senior Notes, if-converted	2,850	0	0
Potentially dilutive shares issuable from stock options and unvested RSUs	1,709	0	0
Diluted weighted-average common shares outstanding, if-converted	42,554	33,734	32,708
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	161	37	2,770
Convertible Debt [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		1,400
Stock options and RSUs [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		1,400	800

Commitments and Contingencies -

Commitments and Contingencies - Commitments for Minimum Rentals under Non-cancelable Leases (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, 2019	$ 9,940
Operating Leases, 2020	10,601
Operating Leases, 2021	10,502
Operating Leases, 2022	8,965
Operating Leases, 2023	8,409
Operating Leases, Thereafter	86,797
Operating Leases, Minimum Payments, Total	135,214
Lease Obligation, 2019	956
Lease Obligation, 2020	967
Lease Obligation, 2021	0
Lease Obligation, 2022	0
Lease Obligation, 2023	0
Lease Obligation, Thereafter	0
Lease Obligation, Minimum Payments, Total	$ 1,923

Commitments and Contingencies_2

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	Jan. 05, 2018USD ($)ft²buildingoption	Dec. 31, 2016USD ($)	Dec. 31, 2018USD ($)Lease	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Leases [Abstract]
Rent expense under operating leases		$ 2,200	$ 10,200	$ 2,100
Sale Leaseback Transaction [Line Items]
Lessee, Sale Leaseback, Renewal Term	5 years
Sale Leaseback Transaction, Gross Proceeds, Investing Activities	$ 146,600		146,644
Number Of Buildings | building	4
Sale Leaseback Transaction, Number Of Buildings | building	2
Lessee, Operating Lease, Term of Contract	15 years
Area under new operating lease | ft²	125,000
Lessee, Sale Leaseback, Option To Extend, Number | option	2
Facility sold			15,000
Capital contributed			3,800
Cash transaction, netting			$ 7,000
Partnership that acquired the facility			25.00%
Lease payments			$ 900
Purchase commitment			9,100
Royalty And License Expense			$ 400	$ 600	$ 800
San Diego [Member]
Sale Leaseback Transaction [Line Items]
Number of extension | Lease			3
Lessee, Finance Lease, Term of Contract			10 years
Amended terms			P5Y

Commitments and Contingencies C

Commitments and Contingencies Contingent Consideration (Acquisitions) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition, Contingent Consideration [Line Items]
Current portion of contingent consideration	$ 3,983	$ 6,293
Contingent consideration non-current portion	15,129	18,008
Bio Helix
Business Acquisition, Contingent Consideration [Line Items]
Contingent consideration—BNP Business		4,600
Fair Value, Inputs, Level 3 [Member]
Business Acquisition, Contingent Consideration [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	$ 1,114	$ 100	$ 500

Industry and Geographic Infor_3

Industry and Geographic Information - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)segment	Dec. 31, 2017USD ($)	Dec. 31, 2016
Revenue, Major Customer [Line Items]
Number of reportable segments | segment	1
Sales [Member]
Revenue, Major Customer [Line Items]
Percentage of risk concentration by major customer	10.00%
Customer Concentration Risk [Member] | Sales [Member]
Revenue, Major Customer [Line Items]
Percentage of risk concentration by major customer	44.00%	54.00%	44.00%
Customer Concentration Risk [Member] | Sales [Member] | Non-US [Member]
Revenue, Major Customer [Line Items]
Percentage of risk concentration by major customer	32.00%	18.00%	17.00%
Geographic Concentration Risk [Member] | Non-US [Member]
Revenue, Major Customer [Line Items]
Accounts receivable	$ 23.4	$ 18.8
Credit Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Accounts receivable	$ 33.3	$ 44.4
Credit Concentration Risk [Member] | Accounts Receivable [Member] | Minimum [Member]
Revenue, Major Customer [Line Items]
Percentage of risk concentration by major customer	10.00%	10.00%

Industry and Geographic Infor_4

Industry and Geographic Information - Sales to Individual Customers in Excess of 10% of Total Revenue (Detail) - Sales [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue, Major Customer [Line Items]
Sales percentage	10.00%
Customer Concentration Risk [Member]
Revenue, Major Customer [Line Items]
Sales percentage	44.00%	54.00%	44.00%
Customer Concentration Risk [Member] | Customer A [Member]
Revenue, Major Customer [Line Items]
Sales percentage	19.00%	20.00%	15.00%
Customer Concentration Risk [Member] | Customer B [Member]
Revenue, Major Customer [Line Items]
Sales percentage	13.00%	13.00%	13.00%
Customer Concentration Risk [Member] | Customer C [Member]
Revenue, Major Customer [Line Items]
Sales percentage	12.00%	21.00%	16.00%

Industry and Geographic Infor_5

Industry and Geographic Information - Long-lived Assets (Excluding Intangible Assets) and Total Net Revenue (Detail) - 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
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	$ 73,901				$ 61,585				$ 73,901	$ 61,585
Revenue from Contract with Customer, Including Assessed Tax	132,588	$ 117,399	$ 103,155	$ 169,143	114,890	$ 50,894	$ 38,267	$ 73,692	522,285	277,743	$ 191,603
Federal [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	72,569				59,833				72,569	59,833
Revenue from Contract with Customer, Including Assessed Tax									354,895	227,611	158,244
Foreign [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets, Total	$ 1,332				$ 1,752				1,332	1,752
Revenue from Contract with Customer, Including Assessed Tax									$ 167,390	$ 50,132	$ 33,359

Industry and Geographic Infor_6

Industry and Geographic Information - Consolidated Net Product Revenues by Disease State (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 522,285	$ 277,743	$ 191,603
Infectious Disease [Member]
Segment Reporting Information [Line Items]
Revenues	183,160	165,099	121,416
Cardiac Immunoassay [Member]
Segment Reporting Information [Line Items]
Revenues	266,524	47,030	0
Specialized Diagnostic Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	53,243	51,978	60,681
Molecular Diagnostic Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	$ 19,358	$ 13,636	$ 9,506

Fair Value Measurement - Assets

Fair Value Measurement - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 206,270	$ 247,459
Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,112	24,301
Deferred consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	187,158	223,158
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Level 1 [Member] | Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Level 1 [Member] | Deferred consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	187,158	223,158
Level 2 [Member] | Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Level 2 [Member] | Deferred consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	187,158	223,158
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,112	24,301
Level 3 [Member] | Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	19,112	24,301
Level 3 [Member] | Deferred consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0

Fair Value Measurement - Additi

Fair Value Measurement - Additional Information (Detail) - USD ($) $ in Thousands	Oct. 06, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low		$ 256,000
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction			$ 220,550	$ 0
Accretion of interest on deferred consideration		10,000	2,608	0
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings		1,114	100	$ 500
Triage Business
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		280,000
Contingent consideration—BNP Business	$ 19,700
Business Combination, Consideration Transferred, Liabilities Incurred	220,600
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction		0
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	19,700
Bio Helix
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent consideration—BNP Business			$ 4,600
Immutopics, Inc
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent consideration—BNP Business		300
Consideration A [Member] | Triage Business
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	$ 16,000
Contingent consideration—BNP Business		$ 24,000

Fair Value Measurement - Change

Fair Value Measurement - Changes in Estimated Fair Value of Contingent Consideration Liabilities (Detail) - Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance	$ 24,301
Cash payments	(6,303)
Net loss recorded for fair value adjustments	(1,114)	$ (100)	$ (500)
Balance		$ 24,301
Contingent consideration
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance	$ 19,112

Employee Benefit Plan - Additio

Employee Benefit Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Compensation Related Costs [Abstract]
Pay contributed by employer	50.00%
Pay contributed by employee	6.00%
Contribution to 401 (K) Plan	$ 2.6	$ 1.5	$ 1.5

- Additional Information (Detai

- Additional Information (Detail) $ in Thousands	Oct. 06, 2017USD ($)payment	Dec. 31, 2018USD ($)payment	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Secured Debt	$ 245,000
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low		$ 256,000
Deferred consideration for acquisition of BNP Business			$ 220,550	$ 0
Triage Business
Business Acquisition [Line Items]
Cash consideration	399,798
Contingent consideration—BNP Business	19,700
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		280,000
Deferred consideration for acquisition of BNP Business		0
Change in amount of contingent consideration, liability	19,700
Consideration A [Member] | Triage Business
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	$ 16,000
Contingent consideration—BNP Business		24,000
Business Combination, Contingent Consideration Arrangements, Number Of Installment Payments | payment	5
Business Combination, Contingent Consideration Arrangements, Amount Of Installment Payment	$ 8,000
Consideration B [Member] | Triage Business
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High		$ 240,000
Business Combination, Contingent Consideration Arrangements, Number Of Installment Payments | payment		6
Business Combination, Contingent Consideration Arrangements, Amount Of Installment Payment		$ 40,000
Consideration C [Member] | Triage Business
Business Acquisition [Line Items]
Inventory related adjustment	$ 205

Acquisition - Consideration (De

Acquisition - Consideration (Details) - USD ($) $ in Thousands	Oct. 06, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Deferred consideration for acquisition of BNP Business			$ 220,550	$ 0
Net consideration		$ 0	$ 14,451	$ 5,061
Triage Business
Business Acquisition [Line Items]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 220,600
Cash consideration	399,798
Deferred consideration for acquisition of BNP Business		$ 0
Contingent consideration—BNP Business	19,700
Net consideration	$ 640,253

Acquisition - Purchase price al

Acquisition - Purchase price allocation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Oct. 06, 2017
Business Acquisition [Line Items]
Goodwill	$ 337,021	$ 337,028
Triage Business
Business Acquisition [Line Items]
Prepaid expenses and other current assets			$ 796
Assets held for sale			146,540
Inventories			52,205
Property, plant and equipment			10,608
Intangible assets			184,900
Goodwill			245,531
Other non-current assets			182
Total assets acquired			640,762
Other current liabilities			(509)
Total net assets and liabilities acquired			$ 640,253

Acquisition - Intangible assets

Acquisition - Intangible assets acquired (Details) - USD ($) $ in Thousands	Oct. 06, 2017	Dec. 31, 2018
Triage Business
Business Acquisition [Line Items]
Intangible Asset	$ 184,900
Purchased technology
Business Acquisition [Line Items]
Weighted-average useful life (years)		9 years 1 month
Purchased technology | Triage Business
Business Acquisition [Line Items]
Intangible Asset	$ 52,400
Weighted-average useful life (years)	10 years
Customer relationships
Business Acquisition [Line Items]
Weighted-average useful life (years)		7 years 10 days
Customer relationships | Triage Business
Business Acquisition [Line Items]
Intangible Asset	$ 115,000
Weighted-average useful life (years)	7 years
Trademarks | Triage Business
Business Acquisition [Line Items]
Intangible Asset	$ 17,500
Weighted-average useful life (years)	10 years

Selected Quarterly Financial _3

Selected Quarterly Financial Data (unaudited) - Quarterly Financial Data (Detail) - 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	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Revenue from Contract with Customer, Including Assessed Tax	$ 132,588	$ 117,399	$ 103,155	$ 169,143	$ 114,890	$ 50,894	$ 38,267	$ 73,692				$ 522,285	$ 277,743	$ 191,603
Cost of Goods and Services Sold												206,572	121,601	79,872
Gross profit	82,132	69,642	57,668	106,271	59,127				$ 29,690	$ 18,826	$ 48,499	315,713	156,142	111,731
Operating income (loss)	27,538	16,894	404	51,093	3,887				(2,537)	(11,027)	19,229	95,929	9,552	(4,439)
Net income (loss)	$ 32,479	$ 10,822	$ (3,076)	$ 33,958	$ (5,088)				$ (5,525)	$ (11,842)	$ 14,290	$ 74,183	$ (8,165)	$ (13,808)
Basic and diluted loss per share	$ 0.82	$ 0.28	$ (0.08)	$ 0.96	$ (0.15)				$ (0.16)	$ (0.35)	$ 0.43
Diluted net earnings (loss) per share	$ 0.78	$ 0.27	$ (0.08)	$ 0.86	$ (0.15)				$ (0.16)	$ (0.35)	$ 0.42	$ 1.86	$ (0.24)	$ (0.42)

Consolidated Valuation and Qu_2

Consolidated Valuation and Qualifying Accounts (Detail) - SEC Schedule, 12-09, Allowance, Credit Loss [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 12,309	$ 7,165	$ 7,488
Additions charged to expense or as reductions to revenue	65,142	36,449	28,329
Deductions	(65,472)	(31,305)	(28,652)
Ending Balance	$ 11,979	$ 12,309	$ 7,165