Company Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
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 and commercial paper. Cash equivalents are maintained with high quality institutions.
Accounts Receivable	Accounts Receivable—The Company sells its products directly to hospitals and reference laboratories in the U.S. as well as to distributors in the U.S. and internationally (see Note 7). 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 $7.2 million and $7.5 million at December 31, 2016 and 2015, 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 15 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. The total expense for depreciation of fixed assets and amortization of leasehold improvements was $13.4 million, $12.7 million and $10.3 million for the years ended December 31, 2016, 2015 and 2014, respectively. Maintenance and minor repairs are charged to operations as incurred.
Intangible Assets	The Company completed its annual evaluation for impairment of goodwill and determined that no impairment of goodwill existed as of December 31, 2016. Goodwill and Intangible Assets—Intangible assets are recorded at cost and amortized on a straight-line basis over their estimated useful lives, except for software development costs and indefinite-lived intangibles such as goodwill. Software development costs associated with software to be sold, 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.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets—The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the total book value of an asset may not be recoverable. An impairment loss is recognized when estimated undiscounted future cash flows expected to result from the use of the asset and the eventual disposition are less than its carrying amount. An impairment loss is equal to the excess of the book value of an asset over its determined fair value.
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 2 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.
Product Shipment Costs	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—Rent expense is recorded on a straight-line basis over the term of the lease. The difference between rent expense and amounts paid under the lease agreement 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 income tax expense.
Fair Value of Financial Instruments	Fair Value of Financial Instruments— The Company uses the fair value hierarchy established in ASC Topic 820, Fair Value Measurements and Disclosures, that requires the valuation of assets and liabilities subject to fair value measurements using a three tiered approach and fair value measurement 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; 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, receivables, accounts payable and accrued liabilities approximate their fair values due to their short-term nature.
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 indemnification 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. 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. Compensation expense for restricted stock units (RSUs) is measured at the grant date and recognized ratably over the vesting period. The fair value of RSUs is determined based on the closing market price of the Company’s common stock on the grant date.
Earnings Per Share	Computation of (Loss) Earnings Per Share—For the years ended December 31, 2016, 2015 and 2014, basic loss per share was computed by dividing net loss by the weighted-average number of common shares outstanding, including restricted stock units vested during the period. Diluted earnings per share (“EPS”) reflects the potential dilution that could occur if the earnings were divided by the weighted-average number of common shares and potentially dilutive common shares from outstanding stock options as well as unvested restricted stock units. Potential dilutive common shares were calculated using the treasury stock method and represent incremental shares issuable upon exercise of the Company’s outstanding stock options and unvested restricted stock units. For the years ended December 31, 2016, 2015 and 2014, there were no differences between the number of common shares used for the basic and diluted EPS computation because the Company incurred a net loss and the effect would be anti-dilutive. Stock options and shares of restricted stock that would have been included in the diluted EPS calculation if the Company had earnings amounted to 0.8 million, 1.0 million and 1.1 million for the years ended December 31, 2016, 2015 and 2014, respectively. Additionally, stock options are excluded from the calculation of diluted EPS when the combined exercise price, unrecognized stock-based compensation and expected tax benefits upon exercise are greater than the average market price for the Company’s common stock because their effect is anti-dilutive. Stock options totaling 2.8 million, 1.9 million and 1.0 million for the years ended December 31, 2016, 2015 and 2014, respectively, were not included in the computation of diluted EPS because the exercise of such options would be anti-dilutive. As discussed in Note 2, the Company issued its 3.25% Convertible Senior Notes due 2020 (“Convertible Senior Notes”) in December 2014. It is the Company’s intent and policy to settle conversions through combination settlement, which essentially involves repayment of an amount of cash equal to the “principal portion” and delivery of the “share amount” in excess of the conversion value over the principal portion in cash or shares of common stock (“conversion premium”). No conversion premium existed as of December 31, 2016, 2015 and 2014; therefore, there was no dilutive impact from the Convertible Senior Notes to diluted EPS during the years ended December 31, 2016 2015 and 2014.
Comprehensive (Loss) Income	Comprehensive Loss—Comprehensive loss includes unrealized gains and losses 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 January 1, 2017, January 3, 2016 and December 28, 2014. For ease of reference, the calendar quarter end dates are used herein.
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. 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 will need to use more judgment and make more estimates than under current 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. The standard will be effective for public entities for annual reporting periods beginning after December 15, 2017, including interim periods therein. The Company has assigned internal resources to assist in the adoption of the new standard and is in the initial stages of its evaluation of the impact of the new standard on its accounting policies, processes and system requirements. The Company has begun the process of identifying, categorizing and analyzing its various revenue streams, however, has not yet completed its assessment of the impact. The Company will continue to evaluate the future impact and method of adoption of ASU 2014-09 and related amendments on the Consolidated Financial Statements and related disclosures throughout 2017. The Company will adopt the new standard beginning January 2018. In August 2014, the FASB issued guidance codified in ASU 2014-15 (Subtopic 205-40), Presentation of Financial Statements - Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The guidance requires management to evaluate whether there are conditions and events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the financial statements are issued (or available to be issued when applicable). Management will be required to make this evaluation for both annual and interim reporting periods and will make certain disclosures if it concludes that substantial doubt exists or when its plans alleviate substantial doubt about the entity’s ability to continue as a going concern. Substantial doubt exists when relevant conditions and events, considered in the aggregate, indicate that it is probable that the entity will be unable to meet its obligations as they become due within one year after the date that the financial statements are issued (or available to be issued). The term probable is used consistently with its use in ASC Topic 450, Contingencies. The guidance is effective for annual periods ending after December 15, 2016 and for interim reporting periods starting in the first quarter 2017, with early adoption permitted. The Company's adoption of this guidance in the annual period ended December 31, 2016 did not have an impact on the consolidated financial statements. In February 2015, the FASB issued guidance codified in ASU 2015-02 (Topic 810), Consolidation - Amendments to the Consolidation Analysis. The guidance affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. Specifically, the guidance amends (i) the identification of variable interests (fees paid to a decision maker or service provider), (ii) the variable interest entity (VIE) characteristics for a limited partnership or similar entity and (iii) the primary beneficiary determination. The guidance is effective for annual periods beginning after December 15, 2015 and for interim reporting periods starting in the first quarter 2016. The Company's adoption of this guidance in the first quarter of 2016 did not have a significant impact on the consolidated financial statements. In July 2015, the FASB issued guidance codified in ASU 2015-11 (Topic 330), Simplifying the Measurement of Inventory. The guidance applies to inventory that is measured using first-in, first-out (“FIFO”) or average cost. Under the guidance, an entity should measure inventory that is within scope at the lower of cost and net realizable value, which is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. The guidance is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years, with early adoption permitted as of the beginning of an interim or annual reporting period. The Company's adoption of this guidance in the first quarter of 2016 did not have a significant impact on the consolidated financial statements. 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-to-use asset representing the right to use the underlying asset for the lease term on the balance sheet. The guidance is effective for fiscal years beginning after December 15, 2018 including interim periods within those years, with early adoption permitted. The Company is currently evaluating the impact of this guidance and expects to adopt the standard in the first quarter of 2019. In March 2016, the FASB issued guidance codified in ASU 2016-09 (Topic 718), Improvements to Employee Share Based Payments Accounting. Under the guidance, entities will no longer record excess tax benefits and certain tax deficiencies in additional paid-in capital (APIC). Instead, they will record all excess tax benefits and tax deficiencies as income tax expense or benefit in the income statement, and APIC pools will be eliminated. In addition, entities will recognize excess tax benefits regardless of whether the benefit reduces taxes payable in the current period. Under current guidance, excess tax benefits are not recognized until the deduction reduces taxes payable. Companies will apply this part of the guidance using a modified retrospective transition method and will record a cumulative-effect adjustment in retained earnings for excess tax benefits not previously recognized. The guidance also allows an employer to repurchase more of an employee’s shares for tax withholding purposes without triggering liability accounting. The guidance is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. Early adoption is permitted, but all of the guidance must be adopted in the same period. The Company has excess tax benefits for which a benefit could not be previously recognized of approximately $1.8 million. Upon adoption the balance of the unrecognized excess tax benefits will be reversed with the impact recorded to (accumulated deficit) retained earnings, including any change to the valuation allowance as a result of the adoption. Due to the full valuation allowance on the U.S. deferred tax assets as of December 31, 2016, the Company does not expect any impact to the financial statements as a result of this adoption in the first quarter of 2017.
Fair Value Measurements and Disclosures	In conjunction with Financial Accounting Standards Board Accounting Standard Update No. 2009-05, Fair Value Measurements and Disclosures (Topic 820), the Company assigned $28.8 million to the licensed technology and $0.7 million as a one-time charge to cost of sales to settle royalty claims. In determining the fair value allocation between the intangible asset licensed technology and the one-time charge to cost of sales, the Company assessed the past and estimated future revenue streams related to present and future products that use the patents that were subject to the Amendment. The effective life and related amortization of the licensed technology was based on the higher of the percentage of usage or the straight-line method. This percentage of usage was determined using the revenues generated from products covered by the patents that were subject to the Amendment. The terms of the Amendment provide for an estimated useful life of 3.5 years for this asset.