Investments (Tables)

12 Months Ended

Dec. 31, 2021

Investments

Schedule of amortized cost and fair value of available-for-sale securities

			Gross		Gross
	Amortized		Unrealized		Unrealized		Estimated
	Cost		Gains		Losses		Fair Value
	(in thousands)
December 31, 2021
U.S. treasuries	$	51,269	$	—	$	(174)	$	51,095
Government agency securities		12,075		—		(23)		12,052
Corporate debt		40,169		—		(134)		40,035
Commercial paper		999		—		—		999
Total	$	104,512	$	—	$	(331)	$	104,181
December 31, 2020
U.S. treasuries	$	149,206	$	14	$	(1)	$	149,219
Corporate debt		32,588		—		(34)		32,554
Commercial paper		7,997		1		—		7,998
Total	$	189,791	$	15	$	(35)	$	189,771

Schedule of fair value and unrealized losses of available-for-sale securities in a loss position

	December 31, 2021				December 31, 2020
			Gross				Gross
	Estimated		Unrealized		Estimated		Unrealized
	Fair Value		Losses		Fair Value		Losses
		(in thousands)
U.S. treasuries	$	51,095	$	(174)	$	19,991	$	(1)
Government agency securities		12,052		(23)		—		—
Corporate debt		40,035		(134)		32,554		(34)
Total	$	103,182	$	(331)	$	52,545	$	(35)

Schedule of contractual maturities of securities classified as available-for-sale

	December 31, 2021
	Amortized		Estimated
	Cost		Fair Value
		(in thousands)
Due in one year or less	$	53,617	$	53,550
Due after one year through two years		50,895		50,631
Total	$	104,512	$	104,181