Marketable Securities and Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2021

The following tables present marketable securities by contractual maturity and security type:


As of December 31, 2021 (in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Due within one year:

Commercial paper	$	105,433	$	1	$	(44)	$	105,390
Corporate debt securities	61,721		—		(70)		61,651
Certificates of deposit	23,528		1		(7)		23,522
U.S. government securities	8,008		—		—		8,008
Due after one year through five years:
Corporate debt securities	37,003		—		(129)		36,874
U.S. government securities	5,094		—		(18)		5,076
Total	$	240,787	$	2	$	(268)	$	240,521


As of December 31, 2020 (in thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Due within one year:
U.S. government securities	$	298,335	$	49	$	(1)	$	298,383
Commercial paper	62,037		9		(15)		62,031
Corporate debt securities	38,309		—		(34)		38,275
Certificates of deposit	17,344		1		(1)		17,344
Due after one year through five years:

U.S. government securities	9,370		5		—		9,375
Total	$	425,395	$	64	$	(51)	$	425,408

Schedule of Financial Assets Measured at Fair Value on a Recurring Basis

The following tables present information about the Company's financial assets measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values:


As of December 31, 2021 (in thousands)	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	47,800	$	—	$	47,800
U.S. government securities	—		—		—		—
Marketable securities:
U.S. government securities	—		13,084		—		13,084
Commercial paper	—		105,390		—		105,390
Corporate debt securities	—		98,525		—		98,525
Certificates of deposit	—		23,522		—		23,522
Total	$	—	$	288,321	$	—	$	288,321


As of December 31, 2020 (in thousands)	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	—	$	46,676	$	—	$	46,676
Certificates of deposit	—		30,000		—		30,000
Marketable securities:
U.S. government securities	—		307,758		—		307,758
Commercial paper	—		62,031		—		62,031
Corporate debt securities	—		38,275		—		38,275
Certificates of deposit	—		17,344		—		17,344
Total	$	—	$	502,084	$	—	$	502,084