Cepheid (CPHD) 10-Q 7 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	Apr. 23, 2015
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	CPHD
Entity Registrant Name	CEPHEID
Entity Central Index Key	1037760
Current Fiscal Year End Date	-19
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		71,785,808

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Current assets:
Cash and cash equivalents	$109,626	$96,663
Short-term investments	200,894	196,729
Accounts receivable, less allowance for doubtful accounts of $241 as of March 31, 2015 and $237 as of December 31, 2014	74,719	68,809
Inventory, net	140,761	132,635
Prepaid expenses and other current assets	29,120	24,274
Total current assets	555,120	519,110
Property and equipment, net	119,009	115,765
Investments	62,798	79,731
Other non-current assets	7,911	7,847
Intangible assets, net	29,341	31,440
Goodwill	39,681	39,681
Total assets	813,860	793,574
Current liabilities:
Accounts payable	55,753	50,435
Accrued compensation	24,984	33,760
Accrued royalties	4,375	5,443
Accrued and other liabilities	33,285	34,761
Current portion of deferred revenue	13,633	13,447
Total current liabilities	132,030	137,846
Long-term portion of deferred revenue	4,687	4,532
Convertible senior notes, net	280,581	278,213
Other liabilities	20,126	18,768
Total liabilities	437,424	439,359
Commitments and contingencies (Note 8)
Shareholders' equity:
Preferred stock, no par value; 5,000,000 shares authorized, none issued or outstanding	0	0
Common stock, no par value; 150,000,000 shares authorized, 71,532,845 and 70,904,388 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively	435,798	422,151
Additional paid-in capital	233,103	225,529
Accumulated other comprehensive income, net	341	247
Accumulated deficit	-292,806	-293,712
Total shareholders' equity	376,436	354,215
Total liabilities and shareholders' equity	$813,860	$793,574

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, except Share data, unless otherwise specified
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$241	$237
Preferred stock, par value	$0	$0
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	$0	$0
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	71,532,845	70,904,388
Common stock, shares outstanding	71,532,845	70,904,388

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Revenue	$132,637	$106,907
Costs and operating expenses:
Cost of sales	61,201	53,083
Collaboration profit sharing	1,267	1,291
Research and development	23,986	21,740
Sales and marketing	25,936	23,458
General and administrative	15,642	13,667
Total costs and operating expenses	128,032	113,239
Income (loss) from operations	4,605	-6,332
Other income (expense):
Interest income	373	153
Interest expense	-3,603	-1,862
Foreign currency exchange loss and other, net	-945	-582
Other expense, net	-4,175	-2,291
Income (loss) before income taxes	430	-8,623
Benefit from (provision for) income taxes	476	-680
Net income (loss)	$906	($9,303)
Basic net income (loss) per share	$0.01	($0.13)
Diluted net income (loss) per share	$0.01	($0.13)
Shares used in computing basic net income (loss) per share	71,262	69,272
Shares used in computing diluted net income (loss) per share	73,189	69,272

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income (loss)	$906	($9,303)
Change in unrealized gains and losses related to cash flow hedges:
Gain recognized in accumulated comprehensive income	404	180
Loss reclassified from accumulated comprehensive income to the statement of operations	23	274
Change in unrealized gains and losses related to available-for-sale investments:
Gain (loss) recognized in accumulated comprehensive income	142	-60
Gain reclassified from accumulated comprehensive income to the statement of operations	0	-2
Other comprehensive income (loss), before tax	569	392
Income tax expense related to items of accumulated comprehensive income, net	-475	0
Comprehensive income (loss)	$1,000	($8,911)

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income (loss)	$906	($9,303)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization of property and equipment	6,045	4,977
Amortization of intangible assets	1,673	919
Unrealized foreign exchange differences	1,455	-52
Amortization of debt discount and transaction costs	2,502	1,257
Stock-based compensation expense	7,557	6,782
Excess tax benefits from stock-based compensation expense	-53	0
Loss on the disposal of property, equipment and intangible assets	142	0
Changes in operating assets and liabilities:
Accounts receivable	-5,910	-4,400
Inventory	-8,160	-15,270
Prepaid expenses and other current assets	-2,299	-5,842
Other non-current assets	-197	122
Accounts payable and other current and non-current liabilities	5,512	3,470
Accrued compensation	-8,776	-1,595
Deferred revenue	341	2,079
Net cash provided by (used in) operating activities	738	-16,856
Cash flows from investing activities:
Capital expenditures	-9,989	-8,762
Cost of acquisitions, net	-3,000	0
Proceeds from sale of an intangible asset	339	0
Proceeds from sales of marketable securities and investments	13,303	18,788
Proceeds from maturities of marketable securities and investments	61,774	4,650
Purchases of marketable securities and investments	-62,494	-259,553
Transfer from restricted cash	31	0
Net cash used in investing activities	-36	-244,877
Cash flows from financing activities:
Net proceeds from the issuance of common shares and exercise of stock options	13,804	21,631
Excess tax benefits from stock-based compensation expense	53	0
Proceeds from borrowings of convertible senior notes, net of issuance costs	0	335,789
Purchase of convertible note capped call hedge	0	-25,082
Principal payment of notes payable	-39	-48
Net cash provided by financing activities	13,818	332,290
Effect of foreign exchange rate change on cash and cash equivalents	-1,557	89
Net increase in cash and cash equivalents	12,963	70,646
Cash and cash equivalents at beginning of period	96,663	66,072
Cash and cash equivalents at end of period	$109,626	$136,718

Organization_and_Summary_of_Si

Organization and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Organization and Summary of Significant Accounting Policies	1. Organization and Summary of Significant Accounting Policies
	Organization and Basis of Presentation
	Cepheid (the “Company”) was incorporated in the State of California on March 4, 1996. The Company is a molecular diagnostics company that develops, manufactures, and markets fully-integrated systems for testing in the Clinical market, as well as for application in the Company’s Non-Clinical legacy market. The Company’s systems enable rapid, sophisticated molecular testing for organisms and genetic-based diseases by automating otherwise complex manual laboratory procedures.
	The Condensed Consolidated Balance Sheet at March 31, 2015, the Condensed Consolidated Statements of Operations for the three months ended March 31, 2015 and 2014, the Condensed Consolidated Statements of Comprehensive Income (Loss) for the three months ended March 31, 2015 and 2014 and the Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2015 and 2014 are unaudited. In the opinion of management, these condensed consolidated financial statements reflect all normal recurring adjustments that management considers necessary for a fair presentation of the Company’s financial position at such dates, and the operating results and cash flows for those periods. The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States. However, certain information or footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles (“GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The results of operations for such periods are not necessarily indicative of the results expected for the remainder of 2015 or for any future period. The Condensed Consolidated Balance Sheet as of December 31, 2014 is derived from audited financial statements as of that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014.
	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with United States GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ from these estimates.
	Cash, Cash Equivalents, Restricted Cash, Short-Term Investments and Non-Current Investments
	Cash and cash equivalents consist of cash on deposit with banks and money market instruments. Interest income includes interest, dividends, amortization of purchase premiums and discounts and realized gains and losses on sales of securities.
	Restricted cash consists of cash contractually restricted for use to develop the Xpert Ebola test in accordance with the Company’s agreements with the Bill and Melinda Gates Foundation (“BMFG”) and the National Philanthropic trust (“NPT”). At March 31, 2015 and December 31, 2014, prepaid expense and other current assets included $1.8 million and $1.9 million of restricted cash, respectively.
	The Company’s marketable debt securities have been classified and accounted for as available-for-sale. The Company determines the appropriate classification of its investments at the time of purchase and re-evaluates the designations at each balance sheet date. The Company classifies its marketable debt securities as cash equivalents, short-term investments or non-current investments based on each instrument’s underlying effective maturity date. All highly liquid investments with maturities of three months or less at the date of purchase are classified as cash equivalents. Marketable debt securities with effective maturities of 12 months or less are classified as short-term, and marketable debt securities with effective maturities greater than 12 months are classified as non-current. The Company’s marketable debt securities are carried at fair value, with the unrealized gains and losses reported within accumulated other comprehensive income (loss), a component of shareholders’ equity. The cost of securities sold is based upon the specific identification method.
	The Company assesses whether an other-than-temporary impairment loss on its investments has occurred due to declines in fair value or other market conditions. With respect to the Company’s debt securities, this assessment takes into account the severity and duration of the decline in value, the Company’s intent to sell the security, whether it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis, and whether or not the Company expects to recover the entire amortized cost basis of the security (that is, a credit loss exists).
	See Note 3, “Investments,” for information and related disclosures regarding the Company’s investments.
	Concentration of Credit Risks and Other Uncertainties
	The carrying amounts for financial instruments consisting of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, and accrued and other liabilities approximate fair value due to their short maturities. Derivative instruments and investments are stated at their estimated fair values, based on quoted market prices for the same or similar instruments. The counterparties to the agreements relating to the Company’s derivative instruments consist of large financial institutions of high credit standing.
	The Company’s main financial institution for banking operations held 54% and 58% of the Company’s cash and cash equivalents as of March 31, 2015 and December 31, 2014, respectively.
	The Company’s accounts receivable are derived from net revenue to customers and distributors located in the United States and other countries. The Company performs credit evaluations of its customers’ financial condition. The Company provides reserves for potential credit losses but has not experienced significant losses to date. There was one direct customer whose accounts receivable balance represented 20% and 26% of total accounts receivable as of March 31, 2015 and December 31, 2014, respectively.
	The Company currently sells products through its direct sales force and third-party distributors. There were no direct customers that accounted for 10% or more of total revenue for the three months ended March 31, 2015 and 2014. No single country outside of the United States represented more than 10% of the Company’s total revenue in any period presented.
	Inventory
	Inventory is stated at the lower of standard cost (which approximates actual cost) or market value, with cost determined on the first-in-first-out method. Allocation of fixed production overheads to conversion costs is based on normal capacity of production. Abnormal amounts of idle facility expense, freight, handling costs, and spoilage are expensed as incurred, and not included in overhead. The Company maintains provisions for excess and obsolete inventory based on management’s estimates of forecasted demand and, where applicable, product expiration.
	The components of inventories were as follows (in thousands):
		March 31, 2015		December 31, 2014
	Raw Materials	$	43,223	$	36,287
	Work in Process		45,179		51,691
	Finished Goods		52,359		44,657
	Inventory	$	140,761	$	132,635
	In addition, capitalized stock-based compensation expense of $1.5 million and $1.6 million were included in inventory as of March 31, 2015 and December 31, 2014, respectively
	Revenue Recognition
	The Company recognizes revenue from sales when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed or determinable, and collectability is reasonably assured. No right of return exists for the Company’s products except in the case of damaged goods. The Company has not experienced any significant returns of its products. Shipping and handling costs are expensed as incurred and included in cost of sales. In those cases where the Company bills shipping and handling costs to customers, the amounts billed are classified as revenue.
	The Company enters into revenue arrangements that may consist of multiple deliverables of its products and services. In situations with multiple deliverables, revenue is recognized upon the delivery of the separate elements. The Company sells service contracts for which revenue is deferred and recognized ratably over the contract period.
	The Company may place an instrument at a customer site under a reagent rental. Under a reagent rental, the Company retains title to the instrument and earns revenue for the usage of the instrument and related maintenance services through the amount charged for reagents and other disposables. Under a reagent rental, a customer may commit to purchasing minimum quantities of reagents at stated prices over a defined contract term, which is typically between three to five years. Revenue is recognized over the term of a reagent rental as reagents and other disposables are shipped and all other revenue recognition criteria have been met. All revenue recognized from reagent rentals is included in reagent and disposable sales in Note 11, “Segment and Significant Concentrations”.
	For multiple element arrangements, the total consideration for an arrangement is allocated among the separate elements in the arrangement based on a selling price hierarchy. The selling price hierarchy for a deliverable is based on: (1) vendor specific objective evidence (“VSOE”), if available; (2) third party evidence of selling price if VSOE is not available; or (3) an estimated selling price, if neither VSOE nor third party evidence is available. Estimated selling price is the Company’s best estimate of the selling price of an element in a transaction. The Company limits the amount of revenue recognized for delivered elements to the amount that is not contingent on the future delivery of products or services or other future performance obligations. The Company recognizes revenue for delivered elements only when it determines there are no uncertainties regarding customer acceptance.
	Revenue includes fees for research and development services, including research and development under grants and government sponsored research and collaboration agreements. Revenue and profit under cost-plus service contracts are recognized as costs are incurred plus negotiated fees. Fixed fees on cost-plus service contracts are recognized ratably over the contract performance period as services are performed. Contract costs include labor and related employee benefits, subcontracting costs and other direct costs, as well as allocations of allowable indirect costs. For contract change orders, claims or similar items, judgment is required for estimating the amounts, assessing the potential for realization, and determining whether realization is probable. From time to time, facts develop that require revisions of revenue recognized or cost estimates. To the extent that a revised estimate affects the current or an earlier period, the cumulative effect of the revision is recognized in the period in which the facts requiring the revision become known. Advance payments received in excess of amounts earned, such as funds received in advance of products to be delivered or services to be performed, are classified as deferred revenue until earned.
	Earnings per Share
	Basic earnings per share is computed by dividing net income or loss for the period by the weighted average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income for the period by the weighted average number of common shares outstanding and common equivalent shares from dilutive stock options, employee stock purchases, restricted stock awards, restricted stock units and shares issuable upon a potential conversion of the convertible senior notes using the treasury stock method. In loss periods, the earnings per share calculation excludes all common equivalent shares because their inclusion would be antidilutive. Anti-dilutive common equivalent shares totaled 6,477,000 and 8,129,000 for the three months ended March 31, 2015 and 2014, respectively.
	The following summarizes the computation of basic and diluted earnings per share (in thousands, except for per share amounts):
		Three Months Ended March 31,
		2015		2014
	Basic:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)
	Diluted:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Effect of dilutive securities:
	Stock options, ESPP, restricted stock units, restricted stock awards and convertible senior notes		1,927		—
	Diluted weighted shares outstanding		73,189		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)
	Recent Accounting Pronouncements
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which supersedes the revenue recognition requirements in ASC 605, Revenue Recognition. The core principal of ASU 2014-09 is to recognize revenue at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments, and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. The effective date will be the first quarter of fiscal year 2017 using one of two retrospective transition methods. The Company has not yet selected a transition method nor has it determined the potential effects on its consolidated financial statements. In April 2015, the FASB proposed delaying the effective date of the new guidance by one additional year.
	In April 2015, the FASB issued ASU No. 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs, which amends limited sections within ASC Subtopic 835-30. The amendments in the new guidance require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by this ASU. The effective date will be the first quarter of fiscal year 2016 and early adoption is permitted. The new guidance must be applied retrospectively to all prior periods presented in the financial statements. The Company has not yet determined if the guidance will be adopted earlier than the required effective date. The Company is evaluating the impact of adopting this new accounting guidance on its financial statements.

Fair_Value

Fair Value	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value	2. Fair Value
	The following table summarizes the fair value hierarchy for the Company’s financial assets (cash, cash equivalents, short-term investments, non-current investments and foreign currency derivatives) and financial liabilities (foreign currency derivatives) measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 (in thousands):
	Balance as of March 31, 2015:
		Level 1		Level 2		Level 3		Total
	Assets:
	Cash and cash equivalents	$	76,230	$	33,396	$	—	$	109,626
	Short-term investments:
	Asset-backed securities		—		48,894		—		48,894
	Corporate debt securities		—		72,833		—		72,833
	Commercial Paper		—		34,878		—		34,878
	Government agency securities		—		32,583		—		32,583
	Other securities		—		11,706		—		11,706
	Total short-term investments		—		200,894		—		200,894
	Foreign currency derivatives		—		6,342		—		6,342
	Investments:
	Asset-backed securities		—		4,797		—		4,797
	Corporate debt securities		—		29,778		—		29,778
	Government agency securities		—		23,002		—		23,002
	Other securities		—		5,221		—		5,221
	Total investments		—		62,798		—		62,798
	Total	$	76,230	$	303,430	$	—	$	379,660
	Liabilities:
	Foreign currency derivatives	$	—	$	5,964	$	—	$	5,964
	Total	$	—	$	5,964	$	—	$	5,964
	Balance as of December 31, 2014:
		Level 1		Level 2		Level 3		Total
	Assets:
	Cash and cash equivalents	$	76,065	$	20,598	$	—	$	96,663
	Short-term investments:
	Asset-backed securities				52,220				52,220
	Corporate debt securities		—		64,202		—		64,202
	Commercial paper		—		56,096		—		56,096
	Government agency securities				15,003				15,003
	Other securities		—		9,208		—		9,208
	Total short-term investments		—		196,729		—		196,729
	Foreign currency derivatives		—		3,887		—		3,887
	Investments:
	Asset-backed securities		—		12,713		—		12,713
	Corporate debt securities		—		22,679		—		22,679
	Government agency securities		—		39,532		—		39,532
	Other securities		—		4,807		—		4,807
	Total investments		—		79,731		—		79,731
	Total	$	76,065	$	300,945	$	—	$	377,010
	Liabilities:
	Foreign currency derivatives	$	—	$	3,812	$	—	$	3,812
	Total	$	—	$	3,812	$	—	$	3,812
	The estimated fair values of the Company’s other financial instruments which are not measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 were as follows (in thousands):
	Balance as of March 31, 2015:
		Level 1		Level 2		Level 3		Total
	Liabilities:
	Convertible senior notes	$	—	$	383,495	$	—	$	383,495
	Total	$	—	$	383,495	$	—	$	383,495
	Balance as of December 31, 2014:
		Level 1		Level 2		Level 3		Total
	Liabilities:
	Convertible senior notes	$	—	$	382,232	$	—	$	382,232
	Total	$	—	$	382,232	$	—	$	382,232
	The Company utilized levels 1 and 2 to value its financial assets on a recurring basis. Level 1 instruments use quoted prices in active markets for identical assets or liabilities, which include the Company’s cash accounts, short-term deposits, and money market funds as these specific assets are liquid. Level 2 instruments are valued using the market approach which uses quoted prices in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 2 instruments include commercial paper, corporate debt securities, United States government securities, government agency securities, asset-backed securities, and other securities as similar or identical instruments can be found in active markets.
	The Company recorded derivative assets and liabilities at fair value. The Company’s derivatives consist of foreign exchange forward contracts. The Company has elected to use the income approach to value the derivatives, using observable Level 2 market expectations at the measurement date and standard valuation techniques to convert future amounts to a single present amount assuming that participants are motivated, but not compelled to transact.
	Level 2 inputs for the valuations are limited to quoted prices for similar assets or liabilities in active markets (specifically foreign currency spot rate and forward points) and inputs other than quoted prices that are observable for the asset or liability (specifically LIBOR rates, credit default spot rates, and company specific LIBOR spread). Mid-market pricing is used as a practical expedient for fair value measurements. The fair value measurement of an asset or liability must reflect the nonperformance risk of the entity and the counterparty. Therefore, the impact of the counterparty’s creditworthiness when in an asset position and the Company’s creditworthiness when in a liability position has also been factored into the fair value measurement of the derivative instruments and did not have a material impact on the fair value of these derivative instruments. Both the counterparty and the Company are expected to continue to perform under the contractual terms of the instruments. The estimated fair value of the convertible senior notes, which we have classified as Level 2 financial instruments, was determined based on the quoted price of the convertible senior notes on March 31, 2015.
	Level 3 assets and liabilities are valued by applying the income approach and are based on significant unobservable inputs that are supported by little or no market activity. The Company had no level 3 financial assets as of March 31, 2015 and December 31, 2014.

Investments

Investments	3 Months Ended
	Mar. 31, 2015
Investments Schedule [Abstract]
Investments	3. Investments
	The Company’s marketable securities as of March 31, 2015, were classified as available-for-sale securities, with changes in fair value recognized in accumulated other comprehensive income, net, a component of shareholders’ equity. Classification of marketable securities as a current asset is based on the intended holding period and realizability of the investment. The following tables summarize available-for-sale marketable securities (in thousands):
	Balance as of March 31, 2015:
		Cost			Gross Unrealized			Gross Unrealized			Estimated Fair
					Gain			Loss			Value
	Short-term investments:
	Asset-backed securities	$	48,909		$	1		$	(16	)	$	48,894
	Commercial paper		68,256			18			—			68,274
	Corporate debt securities		72,839			10			(16	)		72,833
	Government agency securities		32,574			11			(2	)		32,583
	Other securities		11,705			1			—			11,706
	Amounts classified as cash equivalents		(33,392	)		(4	)		—			(33,396	)
	Total short-term investments	$	200,891		$	37		$	(34	)	$	200,894
	Investments:
	Asset-backed securities	$	4,800		$	—		$	(3	)	$	4,797
	Corporate debt securities		29,781			8			(11	)		29,778
	Government agency securities		23,002			6			(6	)		23,002
	Other securities		5,225			—			(4	)		5,221
	Total investments	$	62,808		$	14		$	(24	)	$	62,798
	Balance as of December 31, 2014:
		Cost			Gross Unrealized			Gross Unrealized			Estimated Fair
					Gain			Loss			Value
	Short-term investments:
	Asset-backed securities	$	52,240		$	3		$	(23	)	$	52,220
	Commercial paper		76,683			12			—			76,695
	Corporate debt securities		64,244			2			(45	)		64,201
	Government agency securities		15,000			3			—			15,003
	Other securities		9,206			2			—			9,208
	Amounts classified as cash equivalents		(20,598	)		—			—			(20,598	)
	Total short-term investments	$	196,775		$	22		$	(68	)	$	196,729
	Investments:
	Asset-backed securities	$	12,724		$	—		$	(12	)	$	12,712
	Corporate debt securities		22,709			—			(29	)		22,680
	Government agency securities		39,583			—			(51	)		39,532
	Other securities		4,815			—			(8	)		4,807
	Total investments	$	79,831		$	—		$	(100	)	$	79,731
	For the three months ended March 31, 2015 and 2014, $13.3 million and $18.8 million, respectively, of proceeds from sales of marketable securities were collected. The Company determines gains and losses from sales of marketable securities based on specific identification of the securities sold. Gross realized gains and losses from sales of marketable securities, all of which are reported as a component of “Interest income” in the Condensed Consolidated Statements of Operations, were for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months Ended March 31,
		2015			2014
	Gross realized gains	$	—		$	2
	Gross realized losses		—			—
	Realized gains, net	$	—		$	2
	The fair value of the Company’s marketable securities with unrealized losses at March 31, 2015 and December 31, 2014, and the duration of time that such losses had been unrealized (in thousands) were:
	Balance at March 31, 2015:
		Less Than 12 months						More than 12 months						Total
		Fair Value			Unrealized Loss			Fair Value			Unrealized Loss			Fair Value		Unrealized Loss
	Asset-backed securities	$	45,493		$	(16	)	$	6,117		$	(3	)	$	51,610	$	(19	)
	Corporate debt securities		52,837			(24	)		6,300			(3	)		59,137		(27	)
	Government agency securities		25,994			(8	)		—			—			25,994		(8	)
	Other securities		5,221			(4	)		—			—			5,221		(4	)
	Total	$	129,545		$	(52	)	$	12,417		$	(6	)	$	141,962	$	(58	)
	Balance at December 31, 2014:
		Less Than 12 months						More than 12 months						Total
		Fair Value			Unrealized Loss			Fair Value			Unrealized Loss			Fair Value		Unrealized Loss
	Asset-backed securities	$	54,580		$	(35	)	$	—		$	—		$	54,580	$	(35	)
	Corporate debt securities		79,360			(74	)		—			—			79,360		(74	)
	Government agency securities		39,532			(51	)		—			—			39,532		(51	)
	Other securities		4,807			(8	)		—			—			4,807		(8	)
	Total	$	178,279		$	(168	)	$	—		$	—		$	178,279	$	(168	)
	The Company has evaluated such securities, which consist of investments in asset-backed securities, corporate debt securities, government agency securities, and other securities as of March 31, 2015, and has determined that there was no indication of other-than-temporary impairments. This determination was based on several factors, including the length of time and extent to which fair value has been less than the cost basis, the financial condition and near-term prospects of the debt issuer, and the Company’s intent and ability to hold the securities for a period of time sufficient to allow for any anticipated recovery in market value.
	The following table summarizes the amortized cost and estimated fair value of available-for-sale debt securities at March 31, 2015 and December 31, 2014, by contractual maturity (in thousands):
		March 31, 2015						December 31, 2014
		Amortized Cost			Estimated Fair Value			Amortized Cost			Estimated Fair Value
	Debt securities:
Mature in one year or less	$	165,803		$	165,820		$	150,133		$	150,105
Mature after one year through three years		120,358			120,343			135,675			135,566
Mature in more than three years		10,930			10,925			11,396			11,387
Total debt securities		297,091			297,088			297,204			297,058
Securities with no contractual maturity		—			—			—			—
Total	$	297,091		$	297,088		$	297,204		$	297,058

Derivative_Financial_Instrumen

Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	4. Derivative Financial Instruments
	The Company uses derivatives to partially offset its business exposure to foreign currency exchange risk. The Company may enter into foreign currency forward contracts generally up to twelve months to offset some of the foreign exchange risk on expected future cash flows on certain forecasted revenue, cost of sales, operating expenses and on certain existing assets and liabilities.
	The Company may also enter into foreign currency forward contracts to partially offset the foreign currency exchange gains and losses generated by the re-measurement of certain assets and liabilities. However, the Company may choose not to hedge certain foreign currency exchange exposures for a variety of reasons including, but not limited to, accounting considerations and the prohibitive economic cost of hedging particular exposures.
	The Company records all derivatives in the Condensed Consolidated Balance Sheet at fair value. The Company’s accounting treatment of these instruments is based on whether the instruments are designated as hedge or non-hedge instruments. For derivative instruments that are designated and qualify as cash flow hedges, the Company initially records the effective portion of the gain or loss on the derivative instrument in accumulated other comprehensive income or loss (“AOCI”), a separate component of shareholders’ equity and subsequently reclassifies these amounts into earnings within the same financial statement line item as the hedged item in the period during which the hedged transaction is realized. The ineffective portions of cash flow hedges are recorded in foreign currency exchange loss and other, net.
	The Company had a net deferred gain of $0.4 million and $0.2 million associated with cash flow hedges recorded in AOCI as of March 31, 2015 and December 31, 2014, respectively. Deferred gains and losses associated with cash flow hedges of forecasted foreign currency revenue are recognized as a component of revenues in the same period as the related revenue is recognized, and deferred gains and losses related to cash flow hedges of forecasted expenses are recognized as a component of cost of sales, research and development expense, sales and marketing expense and general and administrative expense in the same period as the related expenses are recognized. The Company’s hedged transactions as of March 31, 2015 are expected to occur within twelve months.
	Derivative instruments designated as cash flow hedges must be de-designated as hedges when it is probable the forecasted hedged transaction will not occur in the initially identified time period or within a subsequent two-month time period. Deferred gains and losses in AOCI associated with such derivative instruments are reclassified immediately into foreign currency exchange loss and other, net. Any subsequent changes in fair value of such derivative instruments are reflected in foreign currency exchange loss and other, net unless they are re-designated as hedges of other transactions. The Company did not recognize any significant net gains or losses related to the loss of hedge designation on discontinued cash flow hedges during the three months ended March 31, 2015 and 2014.
	Gains or losses on derivatives not designated as hedging instruments are recorded in foreign currency exchange loss and other, net. During the three months ended March 31, 2015 and 2014, the Company recognized a gain of $2.0 million and a loss of $0.3 million, respectively, as a component of foreign currency exchange loss and other, net. These amounts represent the net gain or loss on the derivative contracts and do not include changes in the related exposures or ineffective portion or amounts excluded from the effectiveness testing of cash flow hedges.
	The notional principle amounts of the Company’s outstanding derivative instruments designated as cash flow hedges are $154.1 million and $117.2 million as of March 31, 2015 and December 31, 2014, respectively. The notional principle amounts of the Company’s outstanding derivative instruments not designated as cash flow hedges is $38.4 million and $30.4 million as of March 31, 2015 and December 31, 2014, respectively.
	The following tables show the Company’s derivative instruments at gross fair value as reflected in the Condensed Consolidated Balance Sheets as of March 31, 2015 and December 31, 2014, respectively (in thousands):
			March 31, 2015
			Fair Value			Fair Value of			Total Fair Value
			of Derivates			Derivates
			Designated			Not Designated
			as Hedge			as Hedge
			Instruments			Instruments
	Derivative Assets (a):
	Foreign exchange contracts		$	6,335		$	7		$	6,342
	Derivative Liabilities (b):
	Foreign exchange contracts			(5,678	)		(286	)		(5,964	)
			31-Dec-14
			Fair Value			Fair Value of			Total Fair Value
			of Derivates			Derivates
			Designated			Not Designated
			as Hedge			as Hedge
			Instruments			Instruments
	Derivative Assets (a):
	Foreign exchange contracts		$	3,887		$	—		$	3,887
	Derivative Liabilities (b):
	Foreign exchange contracts			(3,685	)		(127	)		(3,812	)
	(a)	The fair value of derivative assets is measured using Level 2 fair value inputs and is recorded as prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets.
	(b)	The fair value of derivative liabilities is measured using Level 2 fair value inputs and is recorded as accrued and other liabilities in the Condensed Consolidated Balance Sheets.
	The following tables show the pre-tax effect of the Company’s derivative instruments designated as cash flow hedges in the Condensed Consolidated Statements of Operations for the three month periods ended March 31, 2015 and 2014 (in thousands):
			Three Months Ended
			Gain Recognized						Loss Reclassified						Loss Recognized - Ineffective Portion and
			in OCI - Effective						from AOCI into						Amount Excluded from  Effectiveness Testing
			Portion						Income - Effective
									Portion
			March 31,			March 31,			March 31,			March 31,			Location	March 31,			March 31,
			2015			2014			2015 (a)			2014 (b)				2015			2014
	Cash flow hedges:
	Foreign exchange contracts		$	404		$	180		$	(23	)	$	(274	)	Foreign currency	$	(86	)	$	—
															exchange loss
															and other, net
	Total		$	404		$	180		$	(23	)	$	(274	)		$	(86	)	$	—
	(a)	Includes gains and losses reclassified from AOCI into net income for the effective portion of cash flow hedges, of which a $2.3 million loss within costs and operating expenses and a $2.3 million gain within revenue, respectively, were recognized within the Condensed Consolidated Statement of Operations for the three months ended March 31, 2015.
	(b)	Includes gains and losses reclassified from AOCI into net income for the effective portion of cash flow hedges, of which a $0.5 million loss within costs and operating expenses and a $0.2 million gain within revenue, respectively, were recognized within the Condensed Consolidated Statement of Operations for the three months ended March 31, 2014.

Intangible_Assets

Intangible Assets	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	5. Intangible Assets
	Intangible assets related to licenses are recorded at cost, less accumulated amortization. Intangible assets related to technology and other intangible assets acquired in acquisitions are recorded at fair value at the date of acquisition, less accumulated amortization. Intangible assets are amortized over their estimated useful lives, ranging from 3 to 15 years, on a straight-line basis. Amortization of intangible assets is primarily included in cost of sales, research and development and sales and marketing in the Condensed Consolidated Statements of Operations.
	The recorded value and accumulated amortization of major classes of intangible assets were as follows (in thousands):
		Gross Carrying		Accumulated			Net Carrying
		Amount		Amortization			Amount
	Balance, March 31, 2015
	Licenses	$	13,594	$	(8,937	)	$	4,657
	Technology acquired in acquisitions		8,613		(8,613	)		—
	Customer relationships and other intangible assets acquired in acquisitions		35,849		(11,165	)		24,684
		$	58,056	$	(28,715	)	$	29,341
	Balance, December 31, 2014
	Licenses	$	13,594	$	(8,477	)	$	5,117
	Technology acquired in acquisitions		8,613		(8,613	)		—
	Customer relationships and other intangible assets acquired in acquisitions		36,582		(10,259	)		26,323
		$	58,789	$	(27,349	)	$	31,440
	Intangible asset amortization expense was $1.7 million and $0.9 million for the three months ended March 31, 2015 and 2014, respectively. The following table summarizes the expected future annual amortization expense of intangible assets recorded on the Company’s Condensed Consolidated Balance Sheet as of March 31, 2015, assuming no impairment charges (in thousands):
	For the Years Ending December 31,	Amortization
		Expense
	2015 (remaining nine months)	$	4,651
	2016		5,745
	2017		5,384
	2018		5,301
	2019		3,781
	Thereafter		4,479
	Total expected future annual amortization	$	29,341

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Acquisitions	6. Acquisitions
	The Company has recorded all acquisitions using the purchase method of accounting and, accordingly, included the results of operations in its consolidated results as of the date of each acquisition. The tangible assets, liabilities and intangible assets (including goodwill) acquired were accounted for based on their estimated fair values. The fair value assigned to assets acquired is based on valuations using the Company’s estimates and assumptions.
	The Company acquired certain intangible assets from a distributor in the United States on October 1, 2014 in order to directly serve the smaller hospital market. The total purchase price for this transaction was $21.0 million, of which $18.0 million was paid in cash in 2014, and $3.0 million was retained subject to certain final price adjustments. The retained amount was recorded in “Accrued and other liabilities” in the Balance Sheet at December 31, 2014 and was paid in full in January 2015. The Company accounted for the transaction as an asset acquisition and recorded two intangible assets: re-acquired exclusive distribution rights, and re-acquired distribution rights and customer relationships of $0.9 million and $19.9 million, respectively. The remaining $0.2 million was recorded as settlement for pre-existing relationships in the statements of operations in 2014.
	For the asset acquisition completed in 2014, re-acquired exclusive distribution rights were assigned a useful life of 3 months, and re-acquired distribution rights and customer relationships assets were assigned a useful life of 6 years beginning from January 1, 2015.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	7. Income Taxes
	For the three months ended March 31, 2015, the Company recorded an income tax benefit of $0.5 million, comprised primarily of ordinary tax benefit of the Company’s foreign subsidiaries, and the tax effect of items in accumulated other comprehensive income. For the three months ended March 31, 2014, the Company recorded an income tax provision of $0.7 million, primarily related to ordinary tax expense of the Company’s foreign subsidiaries.
	The Company’s effective tax rate for the three months ended March 31, 2015 and March 31, 2014 differs from the statutory federal income tax rate of 34%, primarily due to the impact of operations in foreign jurisdictions, as well as income or loss in the United States federal and state jurisdictions for which no tax expense or benefit is recorded. The difference in the effective tax rate for the three months ended March 31, 2015 and March 31, 2014 is primarily due to increased United States income for the three months ended March 31, 2015, for which no income tax expense is recorded in the United States federal and state tax jurisdictions.
	The Company utilizes the liability method of accounting for income taxes. Under the liability method, deferred taxes are determined based on the temporary differences between the financial statement and tax bases of assets and liabilities using enacted tax rates. The Company’s position is to record a valuation allowance when it is more likely than not that some of the deferred tax assets will not be realized. Based on all available objective evidence, the Company believes that it is more likely than not that the net United States deferred tax assets will not be fully realized. Accordingly, the Company continues to maintain a full valuation allowance on its United States deferred tax assets and will do so until there is sufficient evidence to support the reversal of all or some portion of this valuation allowance.
	The Company or one of its subsidiaries files income tax returns in the United States federal jurisdiction and various state and foreign jurisdictions. The Company’s United States and state income tax return years 1996 through 2014 remain open to examination. In addition, the Company files tax returns in multiple foreign taxing jurisdictions with open tax years ranging from 2009 to 2014.
	The Company anticipates that the total unrecognized tax benefits will not significantly change within the next 12 months due to the settlement of audits and the expiration of statutes of limitations. The Company is currently under examination in Sweden. Although the outcome of any tax audit is uncertain, the Company believes that it has adequately provided in its consolidated financial statements for any additional taxes that the Company may be required to pay as a result of such examination.
	The Company recognizes interest and penalties related to uncertain tax positions in income tax expense. In 2015 and 2014, the Company did not recognize any significant interest or penalties related to uncertain tax positions. As of March 31, 2015 and December 31, 2014, the Company had not accrued significant interest or penalties.

Convertible_Senior_Notes

Convertible Senior Notes

3 Months Ended

Mar. 31, 2015

Debt Disclosure [Abstract]

Convertible Senior Notes

8. Convertible Senior Notes

In February 2014, the Company issued $345 million aggregate principal amount of 1.25% convertible senior notes (the “Notes”) due February 1, 2021, unless earlier repurchased by the Company or converted by the holder pursuant to their terms. Interest is payable semiannually in arrears on February 1 and August 1 of each year, commencing on August 1, 2014.

The Notes are governed by an Indenture between the Company, as issuer, and Wells Fargo Bank, National Association, as trustee. The Notes are unsecured and rank: senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the Notes; equal in right of payment to the Company’s existing and future indebtedness that is not so subordinated; effectively subordinated in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally subordinated to all existing and future indebtedness and other liabilities incurred by the Company’s subsidiaries.

Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock or a combination of cash and shares of common stock, at the Company’s election.

The Notes have an initial conversion rate of 15.3616 shares of common stock per $1,000 principal amount of Notes. This represents an initial effective conversion price of approximately $65.10 per share of common stock and approximately 5,300,000 shares upon conversion. Throughout the term of the Notes, the conversion rate may be adjusted upon the occurrence of certain events. Holders of the Notes will not receive any cash payment representing accrued and unpaid interest, if any, upon conversion of a Note, except in limited circumstances. Accrued but unpaid interest will be deemed to be paid by the cash, shares of the Company’s common stock or a combination of cash and shares of the Company’s common stock paid or delivered, as the case may be, to the holder upon conversion of a Note.

Prior to the close of business on the business day immediately preceding August 1, 2020, the Notes will be convertible at the option of holders during certain periods, only upon satisfaction of certain conditions set forth below. On or after August 1, 2020, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their Notes at the conversion rate at any time regardless of whether the conditions set forth below have been met.

Holders may convert all or a portion of their Notes prior to the close of business on the business day immediately preceding August 1, 2020, in multiples of $1,000 principal amount, only under the following circumstances:

•

during any calendar quarter commencing after the calendar quarter ending on March 31, 2014 (and only during such calendar quarter), if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day;

•

during the five business day period after any five consecutive trading day period (the “Notes Measurement Period”) in which the “trading price” (as the term is defined in the Indenture) per $1,000 principal amount of notes for each trading day of such Notes Measurement Period was less than 98% of the product of the last reported sale price of the Company’s common stock on such trading day and the conversion rate on each such trading day; or

•

upon the occurrence of specified corporate events.

As of March 31, 2015, the Notes are not yet convertible.

Based on market data available for publicly traded, senior, unsecured corporate bonds issued by companies in the same industry and with similar maturity, the Company estimated the implied interest rate of its Notes to be approximately 5.0%, assuming no conversion option. Assumptions used in the estimate represent what market participants would use in pricing the liability component, including market interest rates, credit standing, and yield curves, all of which are defined as Level 2 observable inputs. The estimated implied interest rate was applied to the Notes, which resulted in a fair value of the liability component of $270 million upon issuance, calculated as the present value of implied future payments based on the $345 million aggregate principal amount. The excess of the principal amount of the liability component over its carrying amount (“debt discount”) is amortized to interest expense over the term of the Notes. The $75 million difference between the aggregate principal amount of $345 million and the estimated fair value of the liability component was recorded in additional paid-in capital as the Notes were not considered redeemable.

In accounting for the transaction costs related to the issuance of the Notes, the Company allocated the total amount incurred to the liability and equity components based on their estimated relative fair values. Transaction costs attributable to the liability component, totaling $7.2 million, are being amortized to expense over the term of the Notes, and transaction costs attributable to the equity component, totaling $2.0 million, and were netted with the equity component in shareholders’ equity.

The Notes consist of the following (in thousands):

March 31, 2015

December 31, 2014

Liability component:

Principal

345,000

345,000

Less: debt discount, net of amortization

(64,419

)

(66,787

)

Net carrying amount

280,581

278,213

Equity component (a)

73,013

73,013

(a)

Recorded in the condensed consolidated balance sheets within additional paid-in capital, net of $2.0 million issuance costs in equity

The following table sets forth total interest expense recognized related to the Notes (in thousands):

Three months ended

Three months ended

March 31, 2015

March 31, 2014

1.25% coupon

$

1,078

$

575

Amortization of debt issuance costs

134

50

Amortization of debt discount

2,368

1,207

3,580

1,832

As of March 31, 2015 and December 31, 2014, the fair value of the Notes, which was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, quoted price of the Notes in an over-the-counter market (Level 2), and carrying value of debt instruments (carrying value excludes the equity component of the Company’s convertible notes classified in equity) were as follows (in thousands):

March 31, 2015

December 31, 2014

Fair Value

Carrying

Fair Value

Carrying

Value

Value

Convertible Senior Notes

$

383,495

$

280,581

$

382,232

$

278,213

In connection with the issuance of the Notes, the Company entered into capped call transactions with certain counterparties affiliated with the initial purchasers and others. The capped call transactions are expected to reduce potential dilution of earnings per share upon conversion of the Notes. Under the capped call transactions, the Company purchased capped call options that in the aggregate relate to the total number of shares of the Company’s common stock underlying the Notes, with an initial strike price of approximately $65.10 per share, which corresponds to the initial conversion price of the Notes and is subject to anti-dilution adjustments substantially similar to those applicable to the conversion rate of the Notes, and have a cap price of approximately $78.61. The cost of the purchased capped calls of $25.1 million was recorded to shareholders’ equity and will not be re-measured.

Based on the closing price of our common stock of $56.90 on March 31, 2015, the if-converted value of the Notes was less than their respective principal amounts.

Commitments_Contingencies_and_

Commitments, Contingencies and Legal Matters	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments, Contingencies and Legal Matters	9. Commitments, Contingencies and Legal Matters
	Purchase Commitments
	The following table summarizes the Company’s purchase commitments at March 31, 2015 (in thousands):
	Years Ending December 31,	Purchase Commitments
	2015 (remaining nine months)	$	32,909
	2016		—
	2017		—
	2018		—
	2019		—
	Thereafter		—
	Total minimum payments	$	32,909
	Purchase commitments include non-cancellable purchase orders or contracts for the purchase of raw materials used in the manufacturing of the Company’s systems and reagents.
	Legal Matters
	In May 2005, the Company entered into a license agreement with F. Hoffman-La Roche Ltd. and Roche Molecular Systems, Inc. (“Roche”) that provided us with rights under a broad range of Roche patents, including patents relating to the PCR process, reverse transcription-based methods, nucleic acid quantification methods, real-time PCR detection process and composition, and patents relating to methods for detection of viral and cancer targets. A number of the licensed patents expired in the United States prior to the end of August of 2010 and in Europe prior to the end of August of 2011. In August 2010, the Company terminated the Company’s license to United States Patent No. 5,804,375 (the “375 Patent”) and ceased paying United States-related royalties. The Company terminated the entire license agreement in the fourth quarter of 2011. In August 2011, Roche initiated an arbitration proceeding against the Company in the International Chamber of Commerce pursuant to the terms of the terminated agreement. The Company filed an answer challenging arbitral jurisdiction over the issues submitted by Roche and denying that the Company violated any provision of the agreement. A three-member panel has been convened to address these issues in confidential proceedings. On July 30, 2013, the panel determined that it had jurisdiction to decide the claims, a determination that the Company appealed to the Swiss Federal Supreme Court. On October 2, 2013, the arbitration panel determined that it would proceed with the arbitration while this appeal was pending. On February 27, 2014 the Swiss Federal Supreme Court upheld the jurisdiction of the arbitration panel to hear the case, and the case is continuing. The Company believes that it has not violated any provision of the agreement and that the asserted claim of the 375 Patent is expired, invalid, unenforceable, and not infringed.
	Based on its ongoing evaluation of the facts and circumstances of the case, the Company believes that it is probable that this arbitration proceeding could result in a material loss. Accordingly, the Company recorded an estimated charge of $20 million as its best estimate of the potential loss in the fourth quarter of 2014, which was included in accrued and other liabilities in the Company’s condensed consolidated balance sheets. As of March 31, 2015, there was no change in the Company’s best estimate. However, given the inherent uncertainty of arbitration and the nature of the claims in this matter, it is possible that the Company may incur an additional material charge, but an estimate of such a charge cannot be made at this time. The Company continues to strongly dispute Roche’s claims and intends to vigorously defend against them.
	On August 21, 2012 the Company filed a lawsuit against Roche in the United States District Court for the Northern District of California (“the Court”), for a declaratory judgment of (a) invalidity, expiration, and non-infringement of the 375 Patent; and (b) invalidity, unenforceability, expiration and non-infringement of United States Patent No. 6,127,155 (the “155 Patent”). On January 17, 2013, the Court issued an order granting a motion by Roche to stay the suit with respect to the 375 Patent pending resolution of the above noted arbitration proceeding. In the same order, the Court dismissed the Company’s suit with respect to the 155 Patent for lack of subject matter jurisdiction, without considering or ruling on the merits of the Company’s case. The Court left open the possibility that the Company could re-file its case against the 155 Patent in the future. The Company believes that the possibility that these legal proceedings will result in a material adverse effect on the Company’s business is remote.
	On July 16, 2014 Roche filed a lawsuit in the Court, alleging that the Company’s Xpert MTB-RIF product infringes United States Patent No. 5,643,723 (the “723 Patent”), which expired on July 1, 2014. On September 15, 2014, the Company filed its answer and counterclaims denying Roche’s allegations of infringement and asking the Court to find the 723 Patent invalid, unenforceable, and not infringed. On November 10, 2014, the Company filed a petition for inter partes review (“IPR”) of the 723 Patent in the United States Patent and Trademark Office and filed a motion with the Court to stay this lawsuit pending the outcome of the IPR. On January 7, 2015, the Court issued an order staying the lawsuit pending the outcome of the IPR. The Company believes that the possibility that these legal proceedings will result in a material loss is remote.
	The Company may be subject to additional various claims, complaints and legal actions that arise from time to time in the normal course of business. Other than as described above, the Company does not believe it is party to any currently pending legal proceedings that will result in a material adverse effect on its business. There can be no assurance that existing or future legal proceedings arising in the ordinary course of business or otherwise will not have a material adverse effect on the Company’s business, consolidated financial position, results of operations or cash flows.

Employee_Equity_Incentive_Plan

Employee Equity Incentive Plans and Stock-Based Compensation Expense	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Employee Equity Incentive Plans and Stock-Based Compensation Expense	10. Employee Equity Incentive Plans and Stock-Based Compensation Expense
	The following table is a summary of the major categories of stock-based compensation expense recognized in accordance with ASC 718, “Compensation—Stock Compensation” (“ASC 718”) for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Cost of sales	$	1,040		$	381
	Research and development		2,198			2,128
	Sales and marketing		1,450			1,616
	General and administrative		2,869			2,657
	Total stock-based compensation expense	$	7,557		$	6,782
	The following table summarizes option activity under all plans (in thousands, except weighted average exercise price and weighted average remaining contractual term):
		Shares			Weighted			Weighted Average		Instrinic Value
					Average			Remaining
					Exercise Price			Contractual Term
								(in years)
	Outstanding, December 31, 2014		5,581		$	33.2
	Granted		40		$	56.23
	Exercised		(476	)	$	23.3
	Forfeited		(121	)	$	39.95
	Outstanding, March 31, 2015		5,024		$	34.16			4.06	$	114,223
	Exercisable, March 31, 2015		2,857		$	27.42			2.91	$	84,215
	Vested and expected to vest, March 31, 2015		4,868		$	33.85			4	$	112,197
	The following table summarizes all award activity, which consists of restricted stock awards and restricted stock units (in thousands, except weighted average grant date fair value):
		Shares			Weighted Average
					Grant Date Fair
					Value
	Outstanding, December 31, 2014		698		$	40.3
	Granted		51			55.85
	Vested		(56	)		36.76
	Cancelled		(29	)		41.21
	Outstanding, March 31, 2015		664		$	41.75
	The following table summarizes the assumptions used in determining the fair value of the Company’s stock options granted to employees and shares purchased by employees under the Company’s 2012 Employee Stock Purchase Plan (“ESPP”):
		Three Months Ended
		March 31,
		2015			2014
	OPTION SHARES:
	Expected Term (in years)		4.4			4.42
	Volatility		0.38			0.43
	Expected Dividends		—	%		—	%
	Risk Free Interest Rates		1.39	%		1.66	%
	Estimated Forfeitures		6.75	%		7.61	%
	Weighted Average Fair Value Per Share	$	18.55		$	18.43
	ESPP SHARES:
	Expected Term (in years)		1.22			1.25
	Volatility		0.32			0.32
	Expected Dividends		—	%		—	%
	Risk Free Interest Rates		0.26	%		0.17	%
	Weighted Average Fair Value Per Share	$	16.43		$	14.54

Segment_and_Significant_Concen

Segment and Significant Concentrations	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Segment and Significant Concentrations	11. Segment and Significant Concentrations
	The Company and its wholly owned subsidiaries operate in one business segment.
	The following table summarizes revenue in the Clinical and Non-Clinical markets (in thousands):
		Three Months Ended March 31,
		2015		2014
	Revenue by market:
	Clinical Systems	$	16,301	$	17,285
	Clinical Reagents		109,006		83,160
	Total Clinical		125,307		100,445
	Non-Clinical		7,330		6,462
	Total revenue	$	132,637	$	106,907
	The following table summarizes revenue by geographic region (in thousands):
		Three Months Ended
		March 31,
		2015		2014
	Geographic revenue information:
	North America
	Clinical	$	75,473	$	57,286
	Non-Clinical		6,832		5,549
	Total North America		82,305		62,835
	International
	Clinical	$	49,834	$	43,159
	Non-Clinical		498		913
	Total International		50,332		44,072
	Total revenue	$	132,637	$	106,907
	No single country outside of the United States represented more than 10% of the Company’s total sales or total assets in any period presented. The Company recognized revenue of $77.0 million and $61.6 million for sales to United States customers for the three months ended March 31, 2015 and 2014, respectively. As of March 31, 2015 and December 31, 2014, the Company has long lived-assets (excluding intangible assets and goodwill) of $99.6 million and $96.0 million, respectively, which reside in the United States. As of March 31, 2015 and December 31, 2014, the Company has long-lived assets of $19.4 million and $19.8 million, respectively, located outside of the United States, which reside primarily in Sweden and countries in the European Monetary Union.

Related_Party_Transaction

Related Party Transaction	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Related Party Transaction	12. Related party transaction
	The Company sells its products and provides services to Geisinger Health System (“Geisinger”), a physician-led health care system serving multiple regions of Pennsylvania. The President and Chief Executive Officer of Geisinger is also a director of the Company. Net revenues recorded from sales to Geisinger were approximately $0.8 million and $0.4 million for the three months ended March 31, 2015 and 2014, respectively. As of March 31, 2015 and December 31, 2014, the Company had accounts receivable of approximately $0.3 million and $0.2 million due from Geisinger, respectively.

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events
	On April 28, 2015, the shareholders of the Company approved the Cepheid 2015 Equity Incentive Plan (the “2015 EIP”), which was approved by the Company’s Board of Directors on February 10, 2015. The 2015 EIP will replace the Company’s existing 2006 Equity Incentive Plan.

Organization_and_Summary_of_Si1

Organization and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Organization and Basis of Presentation	Organization and Basis of Presentation
	Cepheid (the “Company”) was incorporated in the State of California on March 4, 1996. The Company is a molecular diagnostics company that develops, manufactures, and markets fully-integrated systems for testing in the Clinical market, as well as for application in the Company’s Non-Clinical legacy market. The Company’s systems enable rapid, sophisticated molecular testing for organisms and genetic-based diseases by automating otherwise complex manual laboratory procedures.
	The Condensed Consolidated Balance Sheet at March 31, 2015, the Condensed Consolidated Statements of Operations for the three months ended March 31, 2015 and 2014, the Condensed Consolidated Statements of Comprehensive Income (Loss) for the three months ended March 31, 2015 and 2014 and the Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2015 and 2014 are unaudited. In the opinion of management, these condensed consolidated financial statements reflect all normal recurring adjustments that management considers necessary for a fair presentation of the Company’s financial position at such dates, and the operating results and cash flows for those periods. The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States. However, certain information or footnote disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles (“GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The results of operations for such periods are not necessarily indicative of the results expected for the remainder of 2015 or for any future period. The Condensed Consolidated Balance Sheet as of December 31, 2014 is derived from audited financial statements as of that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements. These condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2014.
Use of Estimates	Use of Estimates
	The preparation of condensed consolidated financial statements in conformity with United States GAAP requires management to make estimates and assumptions that affect the amounts reported in the condensed consolidated financial statements and accompanying notes. We base our estimates on historical experience and on various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ from these estimates.
Cash, Cash Equivalents, Restricted Cash, Short-Term Investments and Non-Current Investments	Cash, Cash Equivalents, Restricted Cash, Short-Term Investments and Non-Current Investments
	Cash and cash equivalents consist of cash on deposit with banks and money market instruments. Interest income includes interest, dividends, amortization of purchase premiums and discounts and realized gains and losses on sales of securities.
	Restricted cash consists of cash contractually restricted for use to develop the Xpert Ebola test in accordance with the Company’s agreements with the Bill and Melinda Gates Foundation (“BMFG”) and the National Philanthropic trust (“NPT”). At March 31, 2015 and December 31, 2014, prepaid expense and other current assets included $1.8 million and $1.9 million of restricted cash, respectively.
	The Company’s marketable debt securities have been classified and accounted for as available-for-sale. The Company determines the appropriate classification of its investments at the time of purchase and re-evaluates the designations at each balance sheet date. The Company classifies its marketable debt securities as cash equivalents, short-term investments or non-current investments based on each instrument’s underlying effective maturity date. All highly liquid investments with maturities of three months or less at the date of purchase are classified as cash equivalents. Marketable debt securities with effective maturities of 12 months or less are classified as short-term, and marketable debt securities with effective maturities greater than 12 months are classified as non-current. The Company’s marketable debt securities are carried at fair value, with the unrealized gains and losses reported within accumulated other comprehensive income (loss), a component of shareholders’ equity. The cost of securities sold is based upon the specific identification method.
	The Company assesses whether an other-than-temporary impairment loss on its investments has occurred due to declines in fair value or other market conditions. With respect to the Company’s debt securities, this assessment takes into account the severity and duration of the decline in value, the Company’s intent to sell the security, whether it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis, and whether or not the Company expects to recover the entire amortized cost basis of the security (that is, a credit loss exists).
	See Note 3, “Investments,” for information and related disclosures regarding the Company’s investments.
Concentration of Credit Risks and Other Uncertainties	Concentration of Credit Risks and Other Uncertainties
	The carrying amounts for financial instruments consisting of cash and cash equivalents, restricted cash, accounts receivable, accounts payable, and accrued and other liabilities approximate fair value due to their short maturities. Derivative instruments and investments are stated at their estimated fair values, based on quoted market prices for the same or similar instruments. The counterparties to the agreements relating to the Company’s derivative instruments consist of large financial institutions of high credit standing.
	The Company’s main financial institution for banking operations held 54% and 58% of the Company’s cash and cash equivalents as of March 31, 2015 and December 31, 2014, respectively.
	The Company’s accounts receivable are derived from net revenue to customers and distributors located in the United States and other countries. The Company performs credit evaluations of its customers’ financial condition. The Company provides reserves for potential credit losses but has not experienced significant losses to date. There was one direct customer whose accounts receivable balance represented 20% and 26% of total accounts receivable as of March 31, 2015 and December 31, 2014, respectively.
	The Company currently sells products through its direct sales force and third-party distributors. There were no direct customers that accounted for 10% or more of total revenue for the three months ended March 31, 2015 and 2014. No single country outside of the United States represented more than 10% of the Company’s total revenue in any period presented.
Inventory	Inventory
	Inventory is stated at the lower of standard cost (which approximates actual cost) or market value, with cost determined on the first-in-first-out method. Allocation of fixed production overheads to conversion costs is based on normal capacity of production. Abnormal amounts of idle facility expense, freight, handling costs, and spoilage are expensed as incurred, and not included in overhead. The Company maintains provisions for excess and obsolete inventory based on management’s estimates of forecasted demand and, where applicable, product expiration.
	The components of inventories were as follows (in thousands):
		March 31, 2015		December 31, 2014
	Raw Materials	$	43,223	$	36,287
	Work in Process		45,179		51,691
	Finished Goods		52,359		44,657
	Inventory	$	140,761	$	132,635
	In addition, capitalized stock-based compensation expense of $1.5 million and $1.6 million were included in inventory as of March 31, 2015 and December 31, 2014, respectively
Revenue Recognition	Revenue Recognition
	The Company recognizes revenue from sales when there is persuasive evidence that an arrangement exists, delivery has occurred, the price is fixed or determinable, and collectability is reasonably assured. No right of return exists for the Company’s products except in the case of damaged goods. The Company has not experienced any significant returns of its products. Shipping and handling costs are expensed as incurred and included in cost of sales. In those cases where the Company bills shipping and handling costs to customers, the amounts billed are classified as revenue.
	The Company enters into revenue arrangements that may consist of multiple deliverables of its products and services. In situations with multiple deliverables, revenue is recognized upon the delivery of the separate elements. The Company sells service contracts for which revenue is deferred and recognized ratably over the contract period.
	The Company may place an instrument at a customer site under a reagent rental. Under a reagent rental, the Company retains title to the instrument and earns revenue for the usage of the instrument and related maintenance services through the amount charged for reagents and other disposables. Under a reagent rental, a customer may commit to purchasing minimum quantities of reagents at stated prices over a defined contract term, which is typically between three to five years. Revenue is recognized over the term of a reagent rental as reagents and other disposables are shipped and all other revenue recognition criteria have been met. All revenue recognized from reagent rentals is included in reagent and disposable sales in Note 11, “Segment and Significant Concentrations”.
	For multiple element arrangements, the total consideration for an arrangement is allocated among the separate elements in the arrangement based on a selling price hierarchy. The selling price hierarchy for a deliverable is based on: (1) vendor specific objective evidence (“VSOE”), if available; (2) third party evidence of selling price if VSOE is not available; or (3) an estimated selling price, if neither VSOE nor third party evidence is available. Estimated selling price is the Company’s best estimate of the selling price of an element in a transaction. The Company limits the amount of revenue recognized for delivered elements to the amount that is not contingent on the future delivery of products or services or other future performance obligations. The Company recognizes revenue for delivered elements only when it determines there are no uncertainties regarding customer acceptance.
	Revenue includes fees for research and development services, including research and development under grants and government sponsored research and collaboration agreements. Revenue and profit under cost-plus service contracts are recognized as costs are incurred plus negotiated fees. Fixed fees on cost-plus service contracts are recognized ratably over the contract performance period as services are performed. Contract costs include labor and related employee benefits, subcontracting costs and other direct costs, as well as allocations of allowable indirect costs. For contract change orders, claims or similar items, judgment is required for estimating the amounts, assessing the potential for realization, and determining whether realization is probable. From time to time, facts develop that require revisions of revenue recognized or cost estimates. To the extent that a revised estimate affects the current or an earlier period, the cumulative effect of the revision is recognized in the period in which the facts requiring the revision become known. Advance payments received in excess of amounts earned, such as funds received in advance of products to be delivered or services to be performed, are classified as deferred revenue until earned.
Earnings per Share	Earnings per Share
	Basic earnings per share is computed by dividing net income or loss for the period by the weighted average number of common shares outstanding during the period. Diluted earnings per share is computed by dividing net income for the period by the weighted average number of common shares outstanding and common equivalent shares from dilutive stock options, employee stock purchases, restricted stock awards, restricted stock units and shares issuable upon a potential conversion of the convertible senior notes using the treasury stock method. In loss periods, the earnings per share calculation excludes all common equivalent shares because their inclusion would be antidilutive. Anti-dilutive common equivalent shares totaled 6,477,000 and 8,129,000 for the three months ended March 31, 2015 and 2014, respectively.
	The following summarizes the computation of basic and diluted earnings per share (in thousands, except for per share amounts):
		Three Months Ended March 31,
		2015		2014
	Basic:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)
	Diluted:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Effect of dilutive securities:
	Stock options, ESPP, restricted stock units, restricted stock awards and convertible senior notes		1,927		—
	Diluted weighted shares outstanding		73,189		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)
Recent Accounting Pronouncements	Recent Accounting Pronouncements
	In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), which supersedes the revenue recognition requirements in ASC 605, Revenue Recognition. The core principal of ASU 2014-09 is to recognize revenue at an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing, and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments, and changes in judgments and assets recognized from costs incurred to obtain or fulfill a contract. The effective date will be the first quarter of fiscal year 2017 using one of two retrospective transition methods. The Company has not yet selected a transition method nor has it determined the potential effects on its consolidated financial statements. In April 2015, the FASB proposed delaying the effective date of the new guidance by one additional year.
	In April 2015, the FASB issued ASU No. 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs, which amends limited sections within ASC Subtopic 835-30. The amendments in the new guidance require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by this ASU. The effective date will be the first quarter of fiscal year 2016 and early adoption is permitted. The new guidance must be applied retrospectively to all prior periods presented in the financial statements. The Company has not yet determined if the guidance will be adopted earlier than the required effective date. The Company is evaluating the impact of adopting this new accounting guidance on its financial statements.

Organization_and_Summary_of_Si2

Organization and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
Components of Inventories	The components of inventories were as follows (in thousands):
		March 31, 2015		December 31, 2014
	Raw Materials	$	43,223	$	36,287
	Work in Process		45,179		51,691
	Finished Goods		52,359		44,657
	Inventory	$	140,761	$	132,635
Computation of Basic and Diluted Earnings Per Share	The following summarizes the computation of basic and diluted earnings per share (in thousands, except for per share amounts):
		Three Months Ended March 31,
		2015		2014
	Basic:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)
	Diluted:
	Net income (loss)	$	906	$	(9,303	)
	Basic weighted shares outstanding		71,262		69,272
	Effect of dilutive securities:
	Stock options, ESPP, restricted stock units, restricted stock awards and convertible senior notes		1,927		—
	Diluted weighted shares outstanding		73,189		69,272
	Net income (loss) per share	$	0.01	$	(0.13	)

Fair_Value_Tables

Fair Value (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table summarizes the fair value hierarchy for the Company’s financial assets (cash, cash equivalents, short-term investments, non-current investments and foreign currency derivatives) and financial liabilities (foreign currency derivatives) measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 (in thousands):
	Balance as of March 31, 2015:
		Level 1		Level 2		Level 3		Total
	Assets:
	Cash and cash equivalents	$	76,230	$	33,396	$	—	$	109,626
	Short-term investments:
	Asset-backed securities		—		48,894		—		48,894
	Corporate debt securities		—		72,833		—		72,833
	Commercial Paper		—		34,878		—		34,878
	Government agency securities		—		32,583		—		32,583
	Other securities		—		11,706		—		11,706
	Total short-term investments		—		200,894		—		200,894
	Foreign currency derivatives		—		6,342		—		6,342
	Investments:
	Asset-backed securities		—		4,797		—		4,797
	Corporate debt securities		—		29,778		—		29,778
	Government agency securities		—		23,002		—		23,002
	Other securities		—		5,221		—		5,221
	Total investments		—		62,798		—		62,798
	Total	$	76,230	$	303,430	$	—	$	379,660
	Liabilities:
	Foreign currency derivatives	$	—	$	5,964	$	—	$	5,964
	Total	$	—	$	5,964	$	—	$	5,964
	Balance as of December 31, 2014:
		Level 1		Level 2		Level 3		Total
	Assets:
	Cash and cash equivalents	$	76,065	$	20,598	$	—	$	96,663
	Short-term investments:
	Asset-backed securities				52,220				52,220
	Corporate debt securities		—		64,202		—		64,202
	Commercial paper		—		56,096		—		56,096
	Government agency securities				15,003				15,003
	Other securities		—		9,208		—		9,208
	Total short-term investments		—		196,729		—		196,729
	Foreign currency derivatives		—		3,887		—		3,887
	Investments:
	Asset-backed securities		—		12,713		—		12,713
	Corporate debt securities		—		22,679		—		22,679
	Government agency securities		—		39,532		—		39,532
	Other securities		—		4,807		—		4,807
	Total investments		—		79,731		—		79,731
	Total	$	76,065	$	300,945	$	—	$	377,010
	Liabilities:
	Foreign currency derivatives	$	—	$	3,812	$	—	$	3,812
	Total	$	—	$	3,812	$	—	$	3,812
Liabilities Measured at Fair Value on Non-Recurring Basis	The estimated fair values of the Company’s other financial instruments which are not measured at fair value on a recurring basis as of March 31, 2015 and December 31, 2014 were as follows (in thousands):
	Balance as of March 31, 2015:
		Level 1		Level 2		Level 3		Total
	Liabilities:
	Convertible senior notes	$	—	$	383,495	$	—	$	383,495
	Total	$	—	$	383,495	$	—	$	383,495
	Balance as of December 31, 2014:
		Level 1		Level 2		Level 3		Total
	Liabilities:
	Convertible senior notes	$	—	$	382,232	$	—	$	382,232
	Total	$	—	$	382,232	$	—	$	382,232

Investments_Tables

Investments (Tables)	3 Months Ended
	Mar. 31, 2015
Investments Schedule [Abstract]
Schedule of Available-for-Sale Marketable Securities	The following tables summarize available-for-sale marketable securities (in thousands):
	Balance as of March 31, 2015:
		Cost			Gross Unrealized			Gross Unrealized			Estimated Fair
					Gain			Loss			Value
	Short-term investments:
	Asset-backed securities	$	48,909		$	1		$	(16	)	$	48,894
	Commercial paper		68,256			18			—			68,274
	Corporate debt securities		72,839			10			(16	)		72,833
	Government agency securities		32,574			11			(2	)		32,583
	Other securities		11,705			1			—			11,706
	Amounts classified as cash equivalents		(33,392	)		(4	)		—			(33,396	)
	Total short-term investments	$	200,891		$	37		$	(34	)	$	200,894
	Investments:
	Asset-backed securities	$	4,800		$	—		$	(3	)	$	4,797
	Corporate debt securities		29,781			8			(11	)		29,778
	Government agency securities		23,002			6			(6	)		23,002
	Other securities		5,225			—			(4	)		5,221
	Total investments	$	62,808		$	14		$	(24	)	$	62,798
	Balance as of December 31, 2014:
		Cost			Gross Unrealized			Gross Unrealized			Estimated Fair
					Gain			Loss			Value
	Short-term investments:
	Asset-backed securities	$	52,240		$	3		$	(23	)	$	52,220
	Commercial paper		76,683			12			—			76,695
	Corporate debt securities		64,244			2			(45	)		64,201
	Government agency securities		15,000			3			—			15,003
	Other securities		9,206			2			—			9,208
	Amounts classified as cash equivalents		(20,598	)		—			—			(20,598	)
	Total short-term investments	$	196,775		$	22		$	(68	)	$	196,729
	Investments:
	Asset-backed securities	$	12,724		$	—		$	(12	)	$	12,712
	Corporate debt securities		22,709			—			(29	)		22,680
	Government agency securities		39,583			—			(51	)		39,532
	Other securities		4,815			—			(8	)		4,807
	Total investments	$	79,831		$	—		$	(100	)	$	79,731
Schedule of Gross Realized Gains and Losses of Marketable Securities	Gross realized gains and losses from sales of marketable securities, all of which are reported as a component of “Interest income” in the Condensed Consolidated Statements of Operations, were for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months Ended March 31,
		2015			2014
	Gross realized gains	$	—		$	2
	Gross realized losses		—			—
	Realized gains, net	$	—		$	2
Schedule of Marketable Securities with Unrealized Losses	The fair value of the Company’s marketable securities with unrealized losses at March 31, 2015 and December 31, 2014, and the duration of time that such losses had been unrealized (in thousands) were:
	Balance at March 31, 2015:
		Less Than 12 months						More than 12 months						Total
		Fair Value			Unrealized Loss			Fair Value			Unrealized Loss			Fair Value		Unrealized Loss
	Asset-backed securities	$	45,493		$	(16	)	$	6,117		$	(3	)	$	51,610	$	(19	)
	Corporate debt securities		52,837			(24	)		6,300			(3	)		59,137		(27	)
	Government agency securities		25,994			(8	)		—			—			25,994		(8	)
	Other securities		5,221			(4	)		—			—			5,221		(4	)
	Total	$	129,545		$	(52	)	$	12,417		$	(6	)	$	141,962	$	(58	)
	Balance at December 31, 2014:
		Less Than 12 months						More than 12 months						Total
		Fair Value			Unrealized Loss			Fair Value			Unrealized Loss			Fair Value		Unrealized Loss
	Asset-backed securities	$	54,580		$	(35	)	$	—		$	—		$	54,580	$	(35	)
	Corporate debt securities		79,360			(74	)		—			—			79,360		(74	)
	Government agency securities		39,532			(51	)		—			—			39,532		(51	)
	Other securities		4,807			(8	)		—			—			4,807		(8	)
	Total	$	178,279		$	(168	)	$	—		$	—		$	178,279	$	(168	)
Schedule of Amortized Cost and Estimated Fair Value of Available-for-Sale Debt Securities by Contractual Maturity	The following table summarizes the amortized cost and estimated fair value of available-for-sale debt securities at March 31, 2015 and December 31, 2014, by contractual maturity (in thousands):
		March 31, 2015						December 31, 2014
		Amortized Cost			Estimated Fair Value			Amortized Cost			Estimated Fair Value
	Debt securities:
	Mature in one year or less	$	165,803		$	165,820		$	150,133		$	150,105
	Mature after one year through three years		120,358			120,343			135,675			135,566
	Mature in more than three years		10,930			10,925			11,396			11,387
	Total debt securities		297,091			297,088			297,204			297,058
	Securities with no contractual maturity		—			—			—			—
	Total	$	297,091		$	297,088		$	297,204		$	297,058

Derivative_Financial_Instrumen1

Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments at Gross Fair Value Reflected in Condensed Consolidated Balance Sheets	The following tables show the Company’s derivative instruments at gross fair value as reflected in the Condensed Consolidated Balance Sheets as of March 31, 2015 and December 31, 2014, respectively (in thousands):
			March 31, 2015
			Fair Value			Fair Value of			Total Fair Value
			of Derivates			Derivates
			Designated			Not Designated
			as Hedge			as Hedge
			Instruments			Instruments
	Derivative Assets (a):
	Foreign exchange contracts		$	6,335		$	7		$	6,342
	Derivative Liabilities (b):
	Foreign exchange contracts			(5,678	)		(286	)		(5,964	)
			31-Dec-14
			Fair Value			Fair Value of			Total Fair Value
			of Derivates			Derivates
			Designated			Not Designated
			as Hedge			as Hedge
			Instruments			Instruments
	Derivative Assets (a):
	Foreign exchange contracts		$	3,887		$	—		$	3,887
	Derivative Liabilities (b):
	Foreign exchange contracts			(3,685	)		(127	)		(3,812	)
	(a)	The fair value of derivative assets is measured using Level 2 fair value inputs and is recorded as prepaid expenses and other current assets in the Condensed Consolidated Balance Sheets.
	(b)	The fair value of derivative liabilities is measured using Level 2 fair value inputs and is recorded as accrued and other liabilities in the Condensed Consolidated Balance Sheets.
Pre-tax Effect of Derivative Instruments Designated as Cash Flow Hedges in Condensed Consolidated Statements of Operations	The following tables show the pre-tax effect of the Company’s derivative instruments designated as cash flow hedges in the Condensed Consolidated Statements of Operations for the three month periods ended March 31, 2015 and 2014 (in thousands):
			Three Months Ended
			Gain Recognized						Loss Reclassified						Loss Recognized - Ineffective Portion and
			in OCI - Effective						from AOCI into						Amount Excluded from  Effectiveness Testing
			Portion						Income - Effective
									Portion
			March 31,			March 31,			March 31,			March 31,			Location	March 31,			March 31,
			2015			2014			2015 (a)			2014 (b)				2015			2014
	Cash flow hedges:
	Foreign exchange contracts		$	404		$	180		$	(23	)	$	(274	)	Foreign currency	$	(86	)	$	—
															exchange loss
															and other, net
	Total		$	404		$	180		$	(23	)	$	(274	)		$	(86	)	$	—
	(a)	Includes gains and losses reclassified from AOCI into net income for the effective portion of cash flow hedges, of which a $2.3 million loss within costs and operating expenses and a $2.3 million gain within revenue, respectively, were recognized within the Condensed Consolidated Statement of Operations for the three months ended March 31, 2015.
	(b)	Includes gains and losses reclassified from AOCI into net income for the effective portion of cash flow hedges, of which a $0.5 million loss within costs and operating expenses and a $0.2 million gain within revenue, respectively, were recognized within the Condensed Consolidated Statement of Operations for the three months ended March 31, 2014.

Intangible_Assets_Tables

Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Net Carrying Value and Accumulated Amortization of Major Classes of Intangible Assets	The recorded value and accumulated amortization of major classes of intangible assets were as follows (in thousands):
		Gross Carrying		Accumulated			Net Carrying
		Amount		Amortization			Amount
	Balance, March 31, 2015
	Licenses	$	13,594	$	(8,937	)	$	4,657
	Technology acquired in acquisitions		8,613		(8,613	)		—
	Customer relationships and other intangible assets acquired in acquisitions		35,849		(11,165	)		24,684
		$	58,056	$	(28,715	)	$	29,341
	Balance, December 31, 2014
	Licenses	$	13,594	$	(8,477	)	$	5,117
	Technology acquired in acquisitions		8,613		(8,613	)		—
	Customer relationships and other intangible assets acquired in acquisitions		36,582		(10,259	)		26,323
		$	58,789	$	(27,349	)	$	31,440
Expected Future Annual Amortization Expense of Intangible Assets	The following table summarizes the expected future annual amortization expense of intangible assets recorded on the Company’s Condensed Consolidated Balance Sheet as of March 31, 2015, assuming no impairment charges (in thousands):
	For the Years Ending December 31,	Amortization
		Expense
	2015 (remaining nine months)	$	4,651
	2016		5,745
	2017		5,384
	2018		5,301
	2019		3,781
	Thereafter		4,479
	Total expected future annual amortization	$	29,341

Convertible_Senior_Notes_Table

Convertible Senior Notes (Tables)	3 Months Ended
	Mar. 31, 2015
Debt Disclosure [Abstract]
Schedule of Convertible Notes	The Notes consist of the following (in thousands):
			March 31, 2015			December 31, 2014
	Liability component:
	Principal			345,000			345,000
	Less: debt discount, net of amortization			(64,419	)		(66,787	)
	Net carrying amount			280,581			278,213
	Equity component (a)			73,013			73,013
	(a)	Recorded in the condensed consolidated balance sheets within additional paid-in capital, net of $2.0 million issuance costs in equity
Schedule of Total Interest Expense Related to Notes	The following table sets forth total interest expense recognized related to the Notes (in thousands):
			Three months ended			Three months ended
			March 31, 2015			March 31, 2014
	1.25% coupon		$	1,078		$	575
	Amortization of debt issuance costs			134			50
	Amortization of debt discount			2,368			1,207
				3,580			1,832
Schedule of Carrying Value of Debt Instrument	As of March 31, 2015 and December 31, 2014, the fair value of the Notes, which was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, quoted price of the Notes in an over-the-counter market (Level 2), and carrying value of debt instruments (carrying value excludes the equity component of the Company’s convertible notes classified in equity) were as follows (in thousands):
			March 31, 2015						December 31, 2014
			Fair Value			Carrying			Fair Value		Carrying
						Value					Value
	Convertible Senior Notes		$	383,495		$	280,581		$	382,232	$	278,213

Commitments_Contingencies_and_1

Commitments, Contingencies and Legal Matters (Tables)	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Summary of Purchase Commitments	The following table summarizes the Company’s purchase commitments at March 31, 2015 (in thousands):
	Years Ending December 31,	Purchase Commitments
	2015 (remaining nine months)	$	32,909
	2016		—
	2017		—
	2018		—
	2019		—
	Thereafter		—
	Total minimum payments	$	32,909

Employee_Equity_Incentive_Plan1

Employee Equity Incentive Plans and Stock-Based Compensation Expense (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock-Based Compensation Expense	The following table is a summary of the major categories of stock-based compensation expense recognized in accordance with ASC 718, “Compensation—Stock Compensation” (“ASC 718”) for the three months ended March 31, 2015 and 2014 (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Cost of sales	$	1,040		$	381
	Research and development		2,198			2,128
	Sales and marketing		1,450			1,616
	General and administrative		2,869			2,657
	Total stock-based compensation expense	$	7,557		$	6,782
Summary of Option Activity	The following table summarizes option activity under all plans (in thousands, except weighted average exercise price and weighted average remaining contractual term):
		Shares			Weighted			Weighted Average		Instrinic Value
					Average			Remaining
					Exercise Price			Contractual Term
								(in years)
	Outstanding, December 31, 2014		5,581		$	33.2
	Granted		40		$	56.23
	Exercised		(476	)	$	23.3
	Forfeited		(121	)	$	39.95
	Outstanding, March 31, 2015		5,024		$	34.16			4.06	$	114,223
	Exercisable, March 31, 2015		2,857		$	27.42			2.91	$	84,215
	Vested and expected to vest, March 31, 2015		4,868		$	33.85			4	$	112,197
Summary of Restricted Stock Plan Activity	The following table summarizes all award activity, which consists of restricted stock awards and restricted stock units (in thousands, except weighted average grant date fair value):
		Shares			Weighted Average
					Grant Date Fair
					Value
	Outstanding, December 31, 2014		698		$	40.3
	Granted		51			55.85
	Vested		(56	)		36.76
	Cancelled		(29	)		41.21
	Outstanding, March 31, 2015		664		$	41.75
Summary of Assumptions to Estimate Fair Value	The following table summarizes the assumptions used in determining the fair value of the Company’s stock options granted to employees and shares purchased by employees under the Company’s 2012 Employee Stock Purchase Plan (“ESPP”):
		Three Months Ended
		March 31,
		2015			2014
	OPTION SHARES:
	Expected Term (in years)		4.4			4.42
	Volatility		0.38			0.43
	Expected Dividends		—	%		—	%
	Risk Free Interest Rates		1.39	%		1.66	%
	Estimated Forfeitures		6.75	%		7.61	%
	Weighted Average Fair Value Per Share	$	18.55		$	18.43
	ESPP SHARES:
	Expected Term (in years)		1.22			1.25
	Volatility		0.32			0.32
	Expected Dividends		—	%		—	%
	Risk Free Interest Rates		0.26	%		0.17	%
	Weighted Average Fair Value Per Share	$	16.43		$	14.54

Segment_and_Significant_Concen1

Segment and Significant Concentrations (Tables)	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Revenue Information by Segments	The following table summarizes revenue in the Clinical and Non-Clinical markets (in thousands):
		Three Months Ended March 31,
		2015		2014
	Revenue by market:
	Clinical Systems	$	16,301	$	17,285
	Clinical Reagents		109,006		83,160
	Total Clinical		125,307		100,445
	Non-Clinical		7,330		6,462
	Total revenue	$	132,637	$	106,907
Segment Revenue by Geography Region	The following table summarizes revenue by geographic region (in thousands):
		Three Months Ended
		March 31,
		2015		2014
	Geographic revenue information:
	North America
	Clinical	$	75,473	$	57,286
	Non-Clinical		6,832		5,549
	Total North America		82,305		62,835
	International
	Clinical	$	49,834	$	43,159
	Non-Clinical		498		913
	Total International		50,332		44,072
	Total revenue	$	132,637	$	106,907

Organization_and_Summary_of_Si3

Organization and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Concentration Risk [Line Items]
Percentage of cash and cash equivalents held by the Company's	54.00%		58.00%
Percentage of one direct customer to total revenue	10.00%	10.00%
Capitalized stock-based compensation expense included in inventory	$1.50		$1.60
Total anti-dilutive common stock equivalent shares	6,477,000	8,129,000
Accounts Receivable [Member] | Credit Concentration Risk [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	20.00%		26.00%
Number of customers	1		1
Prepaid Expenses and Other Current Assets [Member] | Bill and Melinda Gates Foundation and National Philanthropic Trust [Member]
Concentration Risk [Line Items]
Restricted cash	$1.80		$1.90
Minimum [Member]
Concentration Risk [Line Items]
Contract term for purchasing minimum quantities of reagents	P3Y
Maximum [Member]
Concentration Risk [Line Items]
Contract term for purchasing minimum quantities of reagents	P5Y

Organization_and_Summary_of_Si4

Organization and Summary of Significant Accounting Policies - Components of Inventories (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Inventory Disclosure [Abstract]
Raw Materials	$43,223	$36,287
Work in Process	45,179	51,691
Finished Goods	52,359	44,657
Inventory	$140,761	$132,635

Organization_and_Summary_of_Si5

Organization and Summary of Significant Accounting Policies - Computation of Basic and Diluted Earnings Per Share (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Basic:
Net income (loss)	$906	($9,303)
Basic weighted shares outstanding	71,262	69,272
Net income (loss) per share	$0.01	($0.13)
Diluted:
Net income (loss)	$906	($9,303)
Basic weighted shares outstanding	71,262	69,272
Effect of dilutive securities:
Stock options, ESPP, restricted stock units, restricted stock awards and convertible senior notes	1,927	0
Diluted weighted shares outstanding	73,189	69,272
Net income (loss) per share	$0.01	($0.13)

Fair_Value_Assets_and_Liabilit

Fair Value - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$109,626	$96,663
Total short-term investments	200,894	196,729
Foreign currency derivatives	6,342	3,887
Total investments	62,798	79,731
Assets, Total	379,660	377,010
Foreign currency derivatives	5,964	3,812
Liabilities, Total	5,964	3,812
Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	48,894	52,220
Total investments	4,797	12,713
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	72,833	64,202
Total investments	29,778	22,679
Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	34,878	56,096
Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	32,583	15,003
Total investments	23,002	39,532
Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	11,706	9,208
Total investments	5,221	4,807
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	76,230	76,065
Total short-term investments	0	0
Foreign currency derivatives	0	0
Total investments	0	0
Assets, Total	76,230	76,065
Foreign currency derivatives	0	0
Liabilities, Total	0	0
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	33,396	20,598
Total short-term investments	200,894	196,729
Foreign currency derivatives	6,342	3,887
Total investments	62,798	79,731
Assets, Total	303,430	300,945
Foreign currency derivatives	5,964	3,812
Liabilities, Total	5,964	3,812
Fair Value, Measurements, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	0	0
Total short-term investments	0	0
Foreign currency derivatives	0	0
Total investments	0	0
Assets, Total	0	0
Foreign currency derivatives	0	0
Liabilities, Total	0	0
Fair Value, Measurements, Recurring [Member] | Asset-Backed Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Asset-Backed Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	48,894	52,220
Total investments	4,797	12,713
Fair Value, Measurements, Recurring [Member] | Asset-Backed Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	72,833	64,202
Total investments	29,778	22,679
Fair Value, Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	34,878	56,096
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Fair Value, Measurements, Recurring [Member] | Government Agency Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Government Agency Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	32,583	15,003
Total investments	23,002	39,532
Fair Value, Measurements, Recurring [Member] | Government Agency Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Other Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Total investments	0	0
Fair Value, Measurements, Recurring [Member] | Other Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	11,706	9,208
Total investments	5,221	4,807
Fair Value, Measurements, Recurring [Member] | Other Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total short-term investments	0	0
Total investments	$0	$0

Fair_Value_Liabilities_Measure

Fair Value - Liabilities Measured at Fair Value on Non-Recurring Basis (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Liabilities:
Convertible senior notes	$383,495	$382,232
Liabilities, Total	383,495	382,232
Level 2 [Member]
Liabilities:
Convertible senior notes	383,495	382,232
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Liabilities:
Convertible senior notes	0	0
Liabilities, Total	0	0
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Liabilities:
Convertible senior notes	383,495	382,232
Liabilities, Total	383,495	382,232
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Liabilities:
Convertible senior notes	0	0
Liabilities, Total	$0	$0

Fair_Value_Additional_Informat

Fair Value - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial assets	$379,660	$377,010
Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Financial assets	$0	$0

Investments_Schedule_of_Availa

Investments - Schedule of Available-for-Sale Marketable Securities (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	$200,891	$196,775
Available-for-sale marketable securities, Gross Unrealized Gain	37	22
Available-for-sale marketable securities, Gross Unrealized Loss	-34	-68
Available-for-sale marketable securities, Estimated Fair Value	200,894	196,729
Short-Term Investments [Member] | Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	48,909	52,240
Available-for-sale marketable securities, Gross Unrealized Gain	1	3
Available-for-sale marketable securities, Gross Unrealized Loss	-16	-23
Available-for-sale marketable securities, Estimated Fair Value	48,894	52,220
Short-Term Investments [Member] | Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	68,256	76,683
Available-for-sale marketable securities, Gross Unrealized Gain	18	12
Available-for-sale marketable securities, Gross Unrealized Loss	0	0
Available-for-sale marketable securities, Estimated Fair Value	68,274	76,695
Short-Term Investments [Member] | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	72,839	64,244
Available-for-sale marketable securities, Gross Unrealized Gain	10	2
Available-for-sale marketable securities, Gross Unrealized Loss	-16	-45
Available-for-sale marketable securities, Estimated Fair Value	72,833	64,201
Short-Term Investments [Member] | Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	32,574	15,000
Available-for-sale marketable securities, Gross Unrealized Gain	11	3
Available-for-sale marketable securities, Gross Unrealized Loss	-2	0
Available-for-sale marketable securities, Estimated Fair Value	32,583	15,003
Short-Term Investments [Member] | Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	11,705	9,206
Available-for-sale marketable securities, Gross Unrealized Gain	1	2
Available-for-sale marketable securities, Gross Unrealized Loss	0	0
Available-for-sale marketable securities, Estimated Fair Value	11,706	9,208
Short-Term Investments [Member] | Amounts Classified as Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	33,392	20,598
Available-for-sale marketable securities, Gross Unrealized Gain	4	0
Available-for-sale marketable securities, Gross Unrealized Loss	0	0
Available-for-sale marketable securities, Estimated Fair Value	33,396	20,598
Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	62,808	79,831
Available-for-sale marketable securities, Gross Unrealized Gain	14	0
Available-for-sale marketable securities, Gross Unrealized Loss	-24	-100
Available-for-sale marketable securities, Estimated Fair Value	62,798	79,731
Investments [Member] | Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	4,800	12,724
Available-for-sale marketable securities, Gross Unrealized Gain	0	0
Available-for-sale marketable securities, Gross Unrealized Loss	-3	-12
Available-for-sale marketable securities, Estimated Fair Value	4,797	12,712
Investments [Member] | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	29,781	22,709
Available-for-sale marketable securities, Gross Unrealized Gain	8	0
Available-for-sale marketable securities, Gross Unrealized Loss	-11	-29
Available-for-sale marketable securities, Estimated Fair Value	29,778	22,680
Investments [Member] | Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	23,002	39,583
Available-for-sale marketable securities, Gross Unrealized Gain	6	0
Available-for-sale marketable securities, Gross Unrealized Loss	-6	-51
Available-for-sale marketable securities, Estimated Fair Value	23,002	39,532
Investments [Member] | Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale marketable securities, Cost	5,225	4,815
Available-for-sale marketable securities, Gross Unrealized Gain	0	0
Available-for-sale marketable securities, Gross Unrealized Loss	-4	-8
Available-for-sale marketable securities, Estimated Fair Value	$5,221	$4,807

Investments_Additional_Informa

Investments - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Proceeds from sales of marketable securities	$13.30	$18.80

Investments_Schedule_of_Gross_

Investments - Schedule of Gross Realized Gains and Losses of Marketable Securities (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Investments, Debt and Equity Securities [Abstract]
Gross realized gains	$0	$2
Gross realized losses	0	0
Realized gains, net	$0	$2

Investments_Schedule_of_Market

Investments - Schedule of Marketable Securities with Unrealized Losses (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 months, Fair Value	$129,545	$178,279
Less Than 12 months, Unrealized Loss	-52	-168
More than 12 months, Fair Value	12,417	0
More than 12 months, Unrealized Loss	-6	0
Total, Fair Value	141,962	178,279
Total, Unrealized Loss	-58	-168
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 months, Fair Value	45,493	54,580
Less Than 12 months, Unrealized Loss	-16	-35
More than 12 months, Fair Value	6,117	0
More than 12 months, Unrealized Loss	-3	0
Total, Fair Value	51,610	54,580
Total, Unrealized Loss	-19	-35
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 months, Fair Value	52,837	79,360
Less Than 12 months, Unrealized Loss	-24	-74
More than 12 months, Fair Value	6,300	0
More than 12 months, Unrealized Loss	-3	0
Total, Fair Value	59,137	79,360
Total, Unrealized Loss	-27	-74
Government Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 months, Fair Value	25,994	39,532
Less Than 12 months, Unrealized Loss	-8	-51
More than 12 months, Fair Value	0	0
More than 12 months, Unrealized Loss	0	0
Total, Fair Value	25,994	39,532
Total, Unrealized Loss	-8	-51
Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 months, Fair Value	5,221	4,807
Less Than 12 months, Unrealized Loss	-4	-8
More than 12 months, Fair Value	0	0
More than 12 months, Unrealized Loss	0	0
Total, Fair Value	5,221	4,807
Total, Unrealized Loss	($4)	($8)

Investments_Schedule_of_Amorti

Investments - Schedule of Amortized Cost and Estimated Fair Value of Available-for-Sale Debt Securities by Contractual Maturity (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Investments, Debt and Equity Securities [Abstract]
Mature in one year or less, Amortized Cost	$165,803	$150,133
Mature after one year through three years, Amortized Cost	120,358	135,675
Mature in more than three years, Amortized Cost	10,930	11,396
Total debt securities, Amortized Cost	297,091	297,204
Securities with no contractual maturity, Amortized Cost	0	0
Total, Amortized Cost	297,091	297,204
Mature in one year or less, Estimated Fair Value	165,820	150,105
Mature after one year through three years, Estimated Fair Value	120,343	135,566
Mature in more than three years, Estimated Fair Value	10,925	11,387
Total debt securities, Estimated Fair Value	297,088	297,058
Securities with no contractual maturity, Estimated Fair Value	0	0
Total, Estimated Fair Value	$297,088	$297,058

Derivative_Financial_Instrumen2

Derivative Financial Instruments - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Net deferred gain associated with cash flow hedges	$400,000		$200,000
Gain (loss) recognized for foreign currency forward contracts	2,000,000	-300,000
Cash Flow Hedges [Member] | Fair Value of Derivatives Designated as Hedge Instruments [Member]
Derivatives, Fair Value [Line Items]
Notional principle amounts of Company's derivative instruments	154,100,000		117,200,000
Cash Flow Hedges [Member] | Fair Value of Derivatives Not Designated as Hedge Instruments [Member]
Derivatives, Fair Value [Line Items]
Notional principle amounts of Company's derivative instruments	$38,400,000		$30,400,000

Derivative_Financial_Instrumen3

Derivative Financial Instruments - Derivative Instruments at Gross Fair Value Reflected in Condensed Consolidated Balance Sheets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Foreign exchange contracts, Assets	$6,342	$3,887
Foreign exchange contracts, Liabilities	-5,964	-3,812
Fair Value of Derivatives Designated as Hedge Instruments [Member]
Derivatives, Fair Value [Line Items]
Foreign exchange contracts, Assets	6,335	3,887
Foreign exchange contracts, Liabilities	-5,678	-3,685
Fair Value of Derivatives Not Designated as Hedge Instruments [Member]
Derivatives, Fair Value [Line Items]
Foreign exchange contracts, Assets	7	0
Foreign exchange contracts, Liabilities	($286)	($127)

Derivative_Financial_Instrumen4

Derivative Financial Instruments - Pre-tax Effect of Derivative Instruments Designated as Cash Flow Hedges in Condensed Consolidated Statements of Operations (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in OCI - Effective Portion	$404	$180
Loss Reclassified from AOCI into Income-Effective Portion	-23	-274
Loss Recognized - Ineffective Portion and Amount Excluded from Effectiveness Testing	-86	0
Foreign Exchange Contracts [Member] | Cash Flow Hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain Recognized in OCI - Effective Portion	404	180
Loss Reclassified from AOCI into Income-Effective Portion	-23	-274
Foreign Exchange Contracts [Member] | Cash Flow Hedges [Member] | Foreign Currency Exchange Loss and Other, Net [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Loss Recognized - Ineffective Portion and Amount Excluded from Effectiveness Testing	($86)	$0

Derivative_Financial_Instrumen5

Derivative Financial Instruments - Pre-tax Effect of Derivative Instruments Designated as Cash Flow Hedges in Condensed Consolidated Statements of Operations (Parenthetical) (Detail) (Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member], Reclassified from AOCI [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenue [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss)	$2.30	$0.20
Operating Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss)	($2.30)	($0.50)

Intangible_Assets_Additional_I

Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization expense	$1,673	$919
Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	3 years
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful lives of intangible assets	15 years

Intangible_Assets_Net_Carrying

Intangible Assets - Net Carrying Value and Accumulated Amortization of Major Classes of Intangible Assets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$58,056	$58,789
Accumulated Amortization	-28,715	-27,349
Net Carrying Amount	29,341	31,440
Licenses [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	13,594	13,594
Accumulated Amortization	-8,937	-8,477
Net Carrying Amount	4,657	5,117
Technology acquired in acquisitions [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,613	8,613
Accumulated Amortization	-8,613	-8,613
Net Carrying Amount	0	0
Customer relationships and other intangible assets acquired in acquisitions [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	35,849	36,582
Accumulated Amortization	-11,165	-10,259
Net Carrying Amount	$24,684	$26,323

Intangible_Assets_Expected_Fut

Intangible Assets - Expected Future Annual Amortization Expense of Intangible Assets (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
2015 (remaining nine months)	$4,651
2016	5,745
2017	5,384
2018	5,301
2019	3,781
Thereafter	4,479
Net Carrying Amount	$29,341	$31,440

Acquisitions_Additional_Inform

Acquisitions - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Oct. 01, 2014	Mar. 31, 2015	Jan. 31, 2015
Business Acquisition [Line Items]
Legal contingencies and settlements		0.2
Number of acquired intangible assets		2
Distribution rights [Member]
Business Acquisition [Line Items]
Acquired intangible assets		0.9
Estimated useful lives of intangible assets		3 months
Distribution rights and customer relationships [Member]
Business Acquisition [Line Items]
Acquired intangible assets		19.9
Estimated useful lives of intangible assets		6 years
Estimated useful lives of intangible assets, description		6 years beginning from January 1, 2015.
United States Distributors [Member]
Business Acquisition [Line Items]
Total purchase price of transactions	21
Acquisition date		1-Oct-14
Purchase price consideration, cash paid	18
Purchase price consideration payment			$3

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Income Tax Contingency [Line Items]
Benefit from (provision for) income taxes	$476,000	($680,000)
Percentage of federal statutory tax rate	34.00%	34.00%
Uncertain tax positions, Interest and penalties	0	0
Accrued interest or penalties	$0		$0
Domestic [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax examination, open tax year	1996
Domestic [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax examination, open tax year	2014
Foreign [Member] | Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax examination, open tax year	2009
Foreign [Member] | Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Income tax examination, open tax year	2014

Convertible_Senior_Notes_Addit

Convertible Senior Notes - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended
	Feb. 28, 2014	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Debt Instrument [Line Items]
Convertible notes issued		$280,581,000	$278,213,000
Initial strike price of common stock		$65.10
Conversion of notes, cap price		$78.61
Cost of purchased capped calls		25,100,000
Closing price of common stock		$56.90
Convertible Senior Notes [Member]
Debt Instrument [Line Items]
Convertible notes issued	345,000,000
Convertible notes, maturity date		1-Feb-21
Convertible notes fixed rate	1.25%	1.25%		1.25%
Convertible senior notes, Maturity date description		1.25% convertible senior notes (the "Notes") due February 1, 2021, unless earlier repurchased by the Company or converted by the holder pursuant to their terms
Convertible senior notes, interest payment description		Interest is payable semiannually in arrears on February 1 and August 1 of each year, commencing on August 1, 2014.
Convertible debt, conversion rate	15.3616
Convertible debt, conversion rate, principal amount	1,000
Conversion price per share of common stock	$65.10
Debt converted into number of common shares	5,300,000
Convertible debt maturity date		1-Aug-20
Convertible debt, fair value of liability		270,000,000
Convertible debt, present value of future payments		345,000,000	345,000,000
Convertible debt discount, recorded in additional paid in capital		75,000,000
Convertible debt, interest rate		5.00%
Debt instrument transaction costs		7,200,000
Convertible Senior Notes [Member] | Scenario One [Member]
Debt Instrument [Line Items]
Debt instrument trading days	20 days
Consecutive trading days	30 days
Percentage of conversion price	130.00%
Convertible Senior Notes [Member] | Scenario Two [Member]
Debt Instrument [Line Items]
Consecutive trading days	5 days
Percentage of conversion price	98.00%
Equity Component [Member]
Debt Instrument [Line Items]
Debt instrument transaction costs		$2,000,000

Convertible_Senior_Notes_Sched

Convertible Senior Notes - Schedule of Convertible Notes (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Feb. 28, 2014
Liability component:
Net carrying amount	$280,581,000	$278,213,000
Equity component	73,013,000	73,013,000
Convertible Senior Notes [Member]
Liability component:
Principal	345,000,000	345,000,000
Less: debt discount, net of amortization	-64,419,000	-66,787,000
Net carrying amount			$345,000,000

Convertible_Senior_Notes_Sched1

Convertible Senior Notes - Schedule of Convertible Notes (Parenthetical) (Detail) (Equity Component [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015
Equity Component [Member]
Debt Instrument [Line Items]
Debt instrument transaction costs	$2

Convertible_Senior_Notes_Sched2

Convertible Senior Notes - Schedule of Total Interest Expense Related to Notes (Detail) (Convertible Senior Notes [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Convertible Senior Notes [Member]
Interest Expense [Line Items]
1.25% coupon	$1,078	$575
Amortization of debt issuance costs	134	50
Amortization of debt discount	2,368	1,207
Total interest expense	$3,580	$1,832

Convertible_Senior_Notes_Sched3

Convertible Senior Notes - Schedule of Total Interest Expense Related to Notes (Parenthetical) (Detail) (Convertible Senior Notes [Member])	Mar. 31, 2015	Mar. 31, 2014	Feb. 28, 2014
Convertible Senior Notes [Member]
Interest Expense [Line Items]
Coupon interest rate	1.25%	1.25%	1.25%

Convertible_Senior_Notes_Sched4

Convertible Senior Notes - Schedule of Carrying Value of Debt Instrument (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Debt Instrument [Line Items]
Fair Value	$383,495	$382,232
Carrying Value	280,581	278,213
Level 2 [Member]
Debt Instrument [Line Items]
Fair Value	383,495	382,232
Carrying Value	$280,581	$278,213

Commitments_Contingencies_and_2

Commitments, Contingencies and Legal Matters - Summary of Purchase Commitments (Detail) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]
2015 (remaining nine months)	$32,909
2016	0
2017	0
2018	0
2019	0
Thereafter	0
Total minimum payments	$32,909

Commitments_Contingencies_and_3

Commitments, Contingencies and Legal Matters - Additional Information (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Loss Contingencies [Line Items]
Estimated arbitration proceeding charge	$20
Accrued and Other Liabilities [Member]
Loss Contingencies [Line Items]
Estimated arbitration proceeding charge		$20

Employee_Equity_Incentive_Plan2

Employee Equity Incentive Plans and Stock-Based Compensation Expense - Summary of Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$7,557	$6,782
Cost of sales [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,040	381
Research and development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	2,198	2,128
Sales and marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	1,450	1,616
General and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$2,869	$2,657

Employee_Equity_Incentive_Plan3

Employee Equity Incentive Plans and Stock-Based Compensation Expense - Summary of Option Activity (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Shares, Outstanding, Beginning Balance	5,581
Shares, Granted	40
Shares, Exercised	-476
Shares, Forfeited	-121
Shares, Outstanding, Ending Balance	5,024
Shares, Exercisable, March 31, 2015	2,857
Shares, Vested and expected to vest, March 31, 2015	4,868
Weighted Average Exercise Price, Outstanding, Beginning Balance	$33.20
Weighted Average Exercise Price, Granted	$56.23
Weighted Average Exercise Price, Exercised	$23.30
Weighted Average Exercise Price, Forfeited	$39.95
Weighted Average Exercise Price, Outstanding, Ending Balance	$34.16
Weighted Average Exercise Price, Exercisable, March 31, 2015	$27.42
Weighted Average Exercise Price, Vested and expected to vest, March 31, 2015	$33.85
Weighted Average Remaining Contractual Term (in years), Outstanding, March 31, 2015	4 years 22 days
Weighted Average Remaining Contractual Term (in years), Exercisable, March 31, 2015	2 years 10 months 28 days
Weighted Average Remaining Contractual Term (in years), Vested and expected to vest, March 31, 2015	4 years
Intrinsic Value, Outstanding, March 31, 2015	$114,223
Intrinsic Value, Exercisable, March 31, 2015	84,215
Intrinsic Value, Vested and expected to vest, March 31, 2015	$112,197

Employee_Equity_Incentive_Plan4

Employee Equity Incentive Plans and Stock-Based Compensation Expense - Summary of Restricted Stock Plan Activity (Detail) (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding, Beginning Balance, Shares	698
Granted, Shares	51
Vested, Shares	-56
Cancelled, Shares	-29
Outstanding, Ending Balance, Shares	664
Weighted Average Grant Date Fair Value, Outstanding, Beginning Balance	$40.30
Weighted Average Grant Date Fair Value, Granted	$55.85
Weighted Average Grant Date Fair Value, Vested	$36.76
Weighted Average Grant Date Fair Value, Cancelled	$41.21
Weighted Average Grant Date Fair Value, Outstanding, Ending Balance	$41.75

Employee_Equity_Incentive_Plan5

Employee Equity Incentive Plans and Stock-Based Compensation Expense - Summary of Assumptions to Estimate Fair Value (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term (in years)	4 years 4 months 24 days	4 years 5 months 1 day
Volatility	0.38%	0.43%
Expected Dividends	0.00%	0.00%
Risk Free Interest Rates	1.39%	1.66%
Estimated Forfeitures	6.75%	7.61%
Weighted Average Fair Value Per Share	$18.55	$18.43
Employee Stock Purchase Plans One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Term (in years)	1 year 2 months 19 days	1 year 3 months
Volatility	0.32%	0.32%
Expected Dividends	0.00%	0.00%
Risk Free Interest Rates	0.26%	0.17%
Weighted Average Fair Value Per Share	$16.43	$14.54

Segment_and_Significant_Concen2

Segment and Significant Concentrations - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Number of operating business segment	1
Product sales to customers	$132,637,000	$106,907,000
United States [Member]
Segment Reporting Information [Line Items]
Product sales to customers	77,000,000	61,600,000
Long lived-assets	99,600,000		96,000,000
Non-US Countries [Member]
Segment Reporting Information [Line Items]
Long lived-assets	$19,400,000		$19,800,000
Credit Concentration Risk [Member]
Segment Reporting Information [Line Items]
Maximum sales contribution by any other country, percentage	10.00%
Geographic Concentration Risk [Member]
Segment Reporting Information [Line Items]
Maximum assets contribution by any other country, percentage	10.00%

Segment_and_Significant_Concen3

Segment and Significant Concentrations - Revenue Information by Segments (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenue from External Customer [Line Items]
Total revenue	$132,637	$106,907
Clinical [Member]
Revenue from External Customer [Line Items]
Total revenue	125,307	100,445
Non-Clinical [Member]
Revenue from External Customer [Line Items]
Total revenue	7,330	6,462
Systems and other revenue [Member] | Clinical [Member]
Revenue from External Customer [Line Items]
Total revenue	16,301	17,285
Reagent and disposable revenue [Member] | Clinical [Member]
Revenue from External Customer [Line Items]
Total revenue	$109,006	$83,160

Segment_and_Significant_Concen4

Segment and Significant Concentrations - Segment Revenue by Geography Region (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$132,637	$106,907
Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	125,307	100,445
Non-Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	7,330	6,462
North America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	82,305	62,835
North America [Member] | Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	75,473	57,286
North America [Member] | Non-Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	6,832	5,549
International [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	50,332	44,072
International [Member] | Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	49,834	43,159
International [Member] | Non-Clinical [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$498	$913

Related_Party_Transaction_Addi

Related Party Transaction - Additional Information (Detail) (Director [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Director [Member]
Related Party Transaction [Line Items]
Net revenues recorded from Geisinger	$0.80	$0.40
Accounts receivable due from Geisinger	$0.30		$0.20