Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2020

Fair Value Disclosures [Abstract]

Schedule of Marketable Securities

The following is a summary of available-for-sale marketable securities held as of June 30, 2020 and December 31, 2019 (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, 2020
Commercial paper	$	26,897	$	77	$	(1)	$	26,973	$	26,973	$	—
Corporate bonds	1,399,255		12,877		(339)		1,411,793		692,231		719,562
U.S. government agency obligations	362,188		866		(47)		363,007		80,851		282,156
	$	1,788,340	$	13,820	$	(387)	$	1,801,773	$	800,055	$	1,001,718
As of December 31, 2019
Certificates of deposit	$	150,000	$	—	$	—	$	150,000	$	150,000	$	—
Commercial paper	73,829		23		(7)		73,845		73,845		—
Corporate bonds	1,368,668		1,840		(378)		1,370,130		753,538		616,592
U.S. government agency obligations	369,475		80		(74)		369,481		165,623		203,858
	$	1,961,972	$	1,943	$	(459)	$	1,963,456	$	1,143,006	$	820,450

Schedule of Fair Value Measurement

The following table details the fair value measurements within the fair value hierarchy of the Company’s financial assets as of June 30, 2020 and December 31, 2019 (in thousands):

	Total Fair Value		Fair Value Measurements at Reporting Date Using
			Level 1		Level 2
As of June 30, 2020
Money market funds	$	104,131	$	104,131	$	—
Commercial paper	26,973		—		26,973
Corporate bonds	1,411,793		—		1,411,793
U.S. government agency obligations	363,007		—		363,007
Mutual funds	17,383		17,383		—
	$	1,923,287	$	121,514	$	1,801,773
As of December 31, 2019
Money market funds	$	50,779	$	50,779	$	—
Certificates of deposit	150,000		—		150,000
Commercial paper	73,845		—		73,845
Corporate bonds	1,370,130		—		1,370,130
U.S. government agency obligations	369,481		—		369,481
Mutual funds	15,177		15,177		—
	$	2,029,412	$	65,956	$	1,963,456

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 June 30, 2020 and December 31, 2019 were as follows (in thousands):

	June 30, 2020		December 31, 2019
Due in 1 year or less	$	800,055	$	1,143,006
Due after 1 year through 3 years	1,001,718		820,450
	$	1,801,773	$	1,963,456