Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Schedule of Marketable Securities

The following is a summary of available-for-sale marketable securities held as of December 31, 2016 and 2015 (in thousands):

			Gross Unrealized					Aggregate Fair Value		Classification on Balance Sheet
	Amortized Cost									Short-Term Marketable Securities		Long-Term Marketable Securities
As of December 31, 2016			Gains		Losses
Commercial paper	$	40,965	$	—	$	(45	)	$	40,920	$	40,920	$	—
Corporate bonds	984,650		123		(3,697		)	981,076		418,495		562,581
U.S. government agency obligations	267,473		35		(1,366		)	266,142		53,157		212,985
	$	1,293,088	$	158	$	(5,108	)	$	1,288,138	$	512,572	$	775,566
As of December 31, 2015
Commercial paper	$	2,491	$	—	$	(4	)	$	2,487	$	2,487	$	—
Corporate bonds	995,100		73		(3,365		)	991,808		432,585		559,223
U.S. government agency obligations	239,587		41		(575		)	239,053		25,016		214,037
	$	1,237,178	$	114	$	(3,944	)	$	1,233,348	$	460,088	$	773,260

Schedule of Fair Value Measurement

The following table details the fair value measurements within the fair value hierarchy of the Company’s financial assets and liabilities as of December 31, 2016 and 2015 (in thousands):

	Total Fair Value			Fair Value Measurements at Reporting Date Using
				Level 1		Level 2		Level 3
As of December 31, 2016
Cash Equivalents and Marketable Securities:
Money market funds	$	8,726		$	8,726	$	—	$	—
Commercial paper	40,920			—		40,920		—
Corporate bonds	981,076			—		981,076		—
U.S. government agency obligations	266,142			—		266,142		—
Mutual funds	4,022			4,022		—		—
	$	1,300,886		$	12,748	$	1,288,138	$	—
Liabilities:
Contingent consideration obligation related to completed acquisitions	$	(7,100	)	$	—	$	—	$	(7,100	)
As of December 31, 2015
Cash Equivalents and Marketable Securities:
Money market funds	$	1,250		$	1,250	$	—	$	—
Commercial paper	2,487			—		2,487		—
Corporate bonds	991,808			—		991,808		—
U.S. government agency obligations	239,053			—		239,053		—
Mutual funds	1,414			1,414		—		—
	$	1,236,012		$	2,664	$	1,233,348	$	—

Schedule of Activity of Major Classes of Assets Measured at Fair Value Using Level 3 Inputs

The following table reflects the activity for the Company’s major classes of liabilities measured at fair value using Level 3 inputs for the years ended December 31, 2016 and 2015 (in thousands):

	Other Liabilities: Contingent Consideration Obligation
Balance, January 1, 2015	$	(900	)
Fair value adjustment to Velocius contingent consideration included in general and administrative expense	(100		)
Achievement of final milestone related to Velocius contingent consideration	1,000
Balance, December 31, 2015	$	—
Contingent consideration obligation related to Soha Systems, Inc. acquisition	(1,600		)
Contingent consideration obligation related to Cyberfend, Inc. acquisition	(5,500		)
Balance, December 31, 2016	$	(7,100	)

Schedule of Contractual Maturities of Marketable Securities and Other Investment Related Assets

Contractual maturities of the Company’s available-for-sale marketable securities held as of December 31, 2016 and 2015 were as follows (in thousands):

	December 31, 2016		December 31, 2015
Due in 1 year or less	$	512,572	$	460,088
Due after 1 year through 5 years	775,566		773,260
	$	1,288,138	$	1,233,348