Available-for-sale Securities

3 Months Ended

Mar. 31, 2022

Investments Debt And Equity Securities [Abstract]

Available-for-sale securities

4.Available-for-sale securities

The following tables summarize the estimated value of the Company’s available-for-sale marketable securities and cash equivalents and the gross unrealized gains and losses:

	March 31, 2022
			Gross		Gross
	Amortized		unrealized		unrealized			Estimated
	cost		gain		loss			fair value
	(in thousands)
Marketable securities:
Commercial paper	$	170,647	$	2	$	(191	)	$	170,458
U.S. government and agency securities		140,890		3		(827	)		140,066
Corporate bonds		110,829		15		(281	)		110,563
Total marketable securities		422,366		20		(1,299	)		421,087
Cash equivalents:
Money market funds		17,159		—		—			17,159
Commercial paper		56,517		1		(3	)		56,515
U.S. government and agency securities		24,689		—		(3	)		24,686
Total cash equivalents		98,365		1		(6	)		98,360
Total available-for-sale investments	$	520,731	$	21	$	(1,305	)	$	519,447

	December 31, 2021
			Gross		Gross
	Amortized		unrealized		unrealized			Estimated
	cost		gain		loss			fair value
	(in thousands)
Marketable securities:
Commercial paper	$	239,176	$	1	$	(63	)	$	239,114
U.S. government and agency securities		87,926		—		(181	)		87,745
Corporate bonds		141,829		—		(131	)		141,698
Total marketable securities		468,931		1		(375	)		468,557
Cash equivalents:
Money market funds		57,134		—		—			57,134
Commercial paper		52,257		—		(2	)		52,255
U.S. government and agency securities		—		—		—			—
Corporate bonds		—		—		—			—
Total cash equivalents		109,391		—		(2	)		109,389
Total available-for-sale investments	$	578,322	$	1	$	(377	)	$	577,946

The amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are summarized below as of March 31, 2022:

	March 31, 2022
			Gross		Gross
	Amortized		unrealized		unrealized			Estimated
	cost		gain		loss			fair value
	(in thousands)
Mature in one year or less	$	504,958	$	13	$	(1,285	)	$	503,686
Mature after one year through two years		15,773		8		(20	)		15,761
Total marketable securities	$	520,731	$	21	$	(1,305	)	$	519,447