Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2020

The following is a summary of available-for-sale marketable securities held as of September 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 September 30, 2020

Commercial paper	$	11,954	$	42	$	—	$	11,996	$	11,996	$	—
Corporate bonds	1,410,954		11,095		(274)		1,421,775		636,405		785,370
U.S. government agency obligations	359,014		529		(241)		359,302		52,637		306,665
	$	1,781,922	$	11,666	$	(515)	$	1,793,073	$	701,038	$	1,092,035

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 September 30, 2020 and December 31, 2019 (in thousands):


	Total Fair Value		Fair Value Measurements at Reporting Date Using
			Level 1		Level 2
As of September 30, 2020
Money market funds	$	375,752	$	375,752	$	—

Commercial paper	41,994		—		41,994
Corporate bonds	1,421,775		—		1,421,775
U.S. government agency obligations	409,298		—		409,298
Mutual funds	18,500		18,500		—
	$	2,267,319	$	394,252	$	1,873,067




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


	September 30, 2020		December 31, 2019
Due in 1 year or less	$	701,038	$	1,143,006
Due after 1 year through 3 years	1,092,035		820,450
	$	1,793,073	$	1,963,456