Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2014

Marketable Securities [Abstract]

Schedule of Marketable Securities

The following is a summary of available-for-sale marketable securities held as of June 30, 2014 and December 31, 2013 (in thousands):

			Gross Unrealized							Classification on Balance Sheet
	Amortized Cost		Gains		Losses			Aggregate Fair Value		Short-Term Marketable Securities		Long-Term Marketable Securities
As of June 30, 2014
Certificates of deposit	$	53	$	—	$	—		$	53	$	—	$	53
Commercial paper	39,974		—		(9		)	39,965		39,965		—
Corporate bonds	923,490		1,404		(475		)	924,419		384,619		539,800
U.S. government agency obligations	273,792		94		(86		)	273,800		78,024		195,776
	$	1,237,309	$	1,498	$	(570	)	$	1,238,237	$	502,608	$	735,629
As of December 31, 2013
Certificates of deposit	$	222	$	—	$	—		$	222	$	173	$	49
Corporate bonds	736,945		1,197		(281		)	737,861		278,318		459,543
U.S. government agency obligations	174,982		51		(85		)	174,948		61,514		113,434
	$	912,149	$	1,248	$	(366	)	$	913,031	$	340,005	$	573,026

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 at June 30, 2014 and December 31, 2013 (in thousands):

	Total Fair Value			Fair Value Measurements at Reporting Date Using
				Level 1		Level 2		Level 3
As of June 30, 2014
Cash Equivalents and Marketable Securities:
Money market funds	$	1,257		$	1,257	$	—	$	—
Certificates of deposit	53			53		—		—
Commercial paper	39,965			—		39,965		—
Corporate bonds	924,419			—		924,419		—
U.S. government agency obligations	273,800			—		273,800		—
	$	1,239,494		$	1,310	$	1,238,184	$	—
Other Liabilities:
Contingent consideration obligation related to Velocius acquisition	$	(2,900	)	$	—	$	—	$	(2,900	)
As of December 31, 2013
Cash Equivalents and Marketable Securities:
Money market funds	$	40,482		$	40,482	$	—	$	—
Certificates of deposit	3,418			3,418		—		—
Commercial paper	29,999			—		29,999		—
Corporate bonds	737,861			—		737,861		—
U.S. government agency obligations	174,948			—		174,948		—
	$	986,708		$	43,900	$	942,808	$	—
Other Assets:
Note receivable	$	22,879		$	—	$	—	22,879
Other Liabilities:
Contingent consideration obligation related to Velocius acquisition	$	(2,600	)	$	—	$	—	$	(2,600	)

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

Contractual maturities of the Company’s available-for-sale marketable securities held at June 30, 2014 and December 31, 2013 were as follows (in thousands):

	June 30, 2014		December 31, 2013
Due in 1 year or less	$	502,608	$	340,005
Due after 1 year through 5 years	735,629		573,026
	$	1,238,237	$	913,031

Schedule of Fair Value Assets and Liabilities Unobservable Input Reconciliation

The following table reflects the activity for the Company’s major classes of assets and liabilities measured at fair value using Level 3 inputs for the six months ended June 30, 2014 (in thousands):

	Other Assets: Note Receivable			Other Liabilities: Contingent Consideration Obligation
Balance as of January 1, 2014	$	22,879		$	(2,600	)
Unrealized gain on convertible note receivable included in other comprehensive income	2,121			—
Amendment of the convertible note receivable for preferred stock of the issuer and cash	(25,000		)	$	—
Fair value adjustment to contingent consideration included in general and administrative expense	—			(300		)
Balance as of June 30, 2014	$	—		$	(2,900	)