Cash, Cash Equivalents and Marketable Securities

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Marketable Securities

Cash, Cash Equivalents and Marketable SecuritiesThe following tables summarize the amortized cost and the estimated fair value of our cash, cash equivalents and marketable securities as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	26,847	$	—	$	—	$	26,847
Cash equivalents:
Money market funds	38,974		—		—		38,974
Certificate of deposits	1,500		—		—		1,500
Commercial paper	18,996		—		—		18,996
Total cash and cash equivalents	86,317		—		—		86,317
Marketable securities:
U.S. Treasuries	26,924		6		—		26,930
Certificate of deposits	55,283		—		—		55,283
Commercial paper	233,419		—		—		233,419
Corporate debt securities	27,002		59		(2)		27,059
U.S. Government-sponsored enterprises debt securities	6,200		14		—		6,214
Total marketable securities	348,828		79		(2)		348,905
Total cash, cash equivalents and marketable securities	$	435,145	$	79	$	(2)	$	435,222

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	23,887	$	—	$	—	$	23,887
Cash equivalents:
Money market funds	80,986		—		—		80,986
Commercial paper	61,043		—		—		61,043
Certificate of deposits	1,000		—		—		1,000
Total cash equivalents	143,029		—		—		143,029
Total cash and cash equivalents	166,916		—		—		166,916
Marketable securities:
U.S. Treasuries	43,050		1		(1)		43,050
Commercial paper	210,986		—		—		210,986
Certificate of deposits	44,480		—		—		44,480
U.S. Government-sponsored enterprises debt securities	6,200		17		—		6,217
Corporate debt securities	33,288		172		—		33,460
Total marketable securities	338,004		190		(1)		338,193
Total cash, cash equivalents and marketable securities	$	504,920	$	190	$	(1)	$	505,109

As of March 31, 2021, all marketable securities held have maturity dates within one year or less. We regularly review our available-for-sale marketable securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of March 31, 2021, the aggregate difference between the amortized cost and fair value of each security in an unrealized loss position was de minimis. Since any provision for expected credit losses for a security held is limited to the amount the fair value is less than its amortized cost, no allowance for expected credit loss was deemed necessary at March 31, 2021.

See Note 7 for further information regarding the fair value of our financial instruments.