Assets (Tables)

3 Months Ended

Mar. 31, 2015

Assets

Schedule of assets (excluding cash balances) that are measured at fair value on a recurring basis

	Level 1		Level 2		Total
	(in thousands)
March 31, 2015
U.S. treasuries	$	59,732	$	—	$	59,732
Government agency securities	—		4,999		4,999
Corporate debt	—		24,266		24,266
December 31, 2014
U.S. treasuries	$	81,527	$	—	$	81,527
Corporate debt	—		39,045		39,045

Schedule of amortized cost and fair value of available-for-sale securities

			Gross		Gross
	Amortized		Unrealized		Unrealized			Estimated
	Cost		Gains		Losses			Fair Value
	(in thousands)
March 31, 2015
U.S. treasuries	$	59,692	$	42	$	(2	)	$	59,732
Government agency securities	4,998		1		—			4,999
Corporate debt	24,240		27		(1		)	24,266
Total available-for-sale securities	$	88,930	$	70	$	(3	)	$	88,997
December 31, 2014
U.S. treasuries	$	81,506	$	27	$	(6	)	$	81,527
Corporate debt	39,031		20		(6		)	39,045
Total available-for-sale securities	$	120,537	$	47	$	(12	)	$	120,572

Summary of fair value and unrealized losses of available-for-sale securities in a loss position

	March 31, 2015					December 31, 2014
			Gross					Gross
	Estimated		Unrealized			Estimated		Unrealized
	Fair Value		Losses			Fair Value		Losses
	(in thousands)
U.S. treasuries	$	22,001	$	(2	)	$	35,001	$	(6	)
Corporate debt	6,082		(1		)	13,069		(6		)
Total available-for-sale securities in a loss position	$	28,083	$	(3	)	$	48,070	$	(12	)

Schedule of contractual maturities of available-for-sale debt securities

	March 31, 2015
	Amortized		Estimated
	cost		fair value
	(in thousands)
Due in one year or less	$	49,028	$	49,055
Due after one year through two years	39,902		39,942
Total available-for-sale securities	$	88,930	$	88,997

Schedule of inventory

	March 31, 2015		December 31, 2014
	(in thousands)
Materials	$	33,627	$	30,319
Work-in-process	19,381		25,096
Finished goods	4,189		6,056
Total inventory	$	57,197	$	61,471

Schedule of property, plant and equipment

	March 31, 2015		December 31, 2014
	(in thousands)
Land	$	9,392	$	9,392
Building and improvements	51,984		51,979
Machinery and equipment	108,808		104,815
Leasehold improvements	4,440		4,356
Gross property, plant and equipment	174,624		170,542
Less: accumulated depreciation and amortization	94,323		91,790
Net property, plant, and equipment	$	80,301	$	78,752

Schedule of changes in goodwill

	Gross carrying		Accumulated
	amount		impairment		Net amount
	(in thousands)
Goodwill - December 31, 2014	$	238,158	$	123,199	$	114,959
Purchase price allocation adjustment	13		—		13
Goodwill - March 31, 2015	$	238,171	$	123,199	$	114,972

Schedule of intangible assets excluding goodwill

	March 31, 2015						December 31, 2014
			Accumulated						Accumulated
	Gross		Amortization				Gross		Amortization
	Carrying		and		Net		Carrying		and		Net
	Amount		Impairment		Amount		Amount		Impairment		Amount
	(in thousands)
Technology	$	222,358	$	109,881	$	112,477	$	222,358	$	106,342	$	116,016
Customer relationships	47,885		16,793		31,092		47,885		14,918		32,967
Trademarks and tradenames	3,050		1,406		1,644		3,050		1,096		1,954
Indefinite-lived trademark	2,900		—		2,900		2,900		—		2,900
Other	6,320		3,087		3,233		6,320		849		5,471
Total	$	282,513	$	131,167	$	151,346	$	282,513	$	123,205	$	159,308