Marketable Securities and Equity Investments (Tables)

9 Months Ended

Sep. 30, 2019

Investments, Debt and Equity Securities [Abstract]

Summary of cash equivalents and marketable securities

A summary of the Company’s cash equivalents and marketable securities, which are recorded at fair value (and do not include $1.9 billion and $1.4 billion of cash as of September 30, 2019 and December 31, 2018, respectively), is shown below:

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value
	(in thousands)
As of September 30, 2019
Cash equivalents:
Money market funds	$	1,476,254	$	—	$	—		$	1,476,254
U.S. Treasury securities	5,892		1		—			5,893
Government-sponsored enterprise securities	13,370		—		—			13,370
Commercial paper	50,125		1		(7		)	50,119
Total cash equivalents	1,545,641		2		(7		)	1,545,636
Marketable securities:
Government-sponsored enterprise securities	14,188		29		—			14,217
Corporate debt securities	264,613		465		(27		)	265,051
Commercial paper	82,825		113		—			82,938
Total marketable debt securities	361,626		607		(27		)	362,206
Corporate equity securities	133,157		107,450		(4,423		)	236,184
Total marketable securities	$	494,783	$	108,057	$	(4,450	)	$	598,390
As of December 31, 2018
Cash equivalents:
Money market funds	$	1,226,603	$	—	$	—		$	1,226,603
U.S. Treasury securities	5,967		—		(1		)	5,966
Government-sponsored enterprise securities	7,124		—		(1		)	7,123
Commercial paper	58,271		—		(3		)	58,268
Total cash equivalents	1,297,965		—		(5		)	1,297,960
Marketable securities:
U.S. Treasury securities	6,026		—		—			6,026
Government-sponsored enterprise securities	10,704		—		—			10,704
Corporate debt securities	234,088		27		(450		)	233,665
Commercial paper	100,498		—		(108		)	100,390
Total marketable debt securities	351,316		27		(558		)	350,785
Corporate equity securities	133,157		40,619		(6,453		)	167,323
Total marketable securities	$	484,473	$	40,646	$	(7,011	)	$	518,108

Available-for-sale debt securities were recorded in the Company's condensed consolidated balance sheets at fair value as follows:

	As of September 30, 2019		As of December 31, 2018
	(in thousands)
Cash and cash equivalents	$	1,545,636	$	1,297,960
Marketable securities	362,206		350,785
Total	$	1,907,842	$	1,648,745

Available-for-sale debt securities by contractual maturity were as follows:

	As of September 30, 2019		As of December 31, 2018
	(in thousands)
Matures within one year	$	1,778,426	$	1,647,500
Matures after one year through five years	129,416		1,245
Total	$	1,907,842	$	1,648,745