Amortized cost, gross unrealized gains/losses in accumulated other comprehensive loss and fair value of marketable debt securities, available-for-sale, by type of security as of March 31, 2023 and December 31, 2022 consisted of the following (in thousands):


	March 31, 2023
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Short-term investments:
Corporate debt security	$	24,185	$	—	$	(303)	$	23,882
U.S. treasuries	651		—		(1)		650
Asset-backed security and other	3,029		—		(33)		2,996


	$	27,865	$	—	$	(337)	$	27,528


	December 31, 2022
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Short-term investments:
Corporate debt security	$	40,177	$	—	$	(612)	$	39,565
U.S. treasuries	2,201		—		(21)		2,180
Asset-backed security and other	5,324		—		(76)		5,248
Non-U.S. government and supranational bonds	3,685		—		(30)		3,655

	$	51,387	$	—	$	(739)	$	50,648

As of March 31, 2023, no allowance for credit losses was recorded related to an impairment of available-for-sale securities.

The Company’s investments in marketable debt securities, available-for-sale that have been in a continuous unrealized loss position by type of security as of March 31, 2023 and December 31, 2022 consisted of the following (in thousands):


	March 31, 2023
	Less than 12 months				12 months or greater				Total
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Corporate debt security	$	405	$	—	$	23,477	$	(303)	$	23,882	$	(303)
U.S. treasuries	—		—		650		(1)		650		(1)
Asset-backed security and other	—		—		2,996		(33)		2,996		(33)


	$	405	$	—	$	27,123	$	(337)	$	27,528	$	(337)


	December 31, 2022
	Less than 12 months				12 months or greater				Total
	Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses
Corporate debt security	$	1,790	$	(2)	$	37,775	$	(610)	$	39,565	$	(612)
U.S. treasuries	—		—		2,180		(21)		2,180		(21)
Asset-backed security and other	—		—		5,248		(76)		5,248		(76)
Non-U.S. government and supranational bonds	—		—		3,655		(30)		3,655		(30)

	$	1,790	$	(2)	$	48,858	$	(737)	$	50,648	$	(739)

Gross realized gains and gross realized losses from the sales of the Company’s marketable debt securities, available-for-sale for the three months ended March 31, 2023 and 2022 consisted of the following (in thousands):


	Three Months Ended March 31,
	2023		2022
Gross realized gains	$	—	$	—
Gross realized losses	$	(91)	$	(6)

Amortized cost and fair value of marketable debt securities, available-for-sale by contractual maturity as of March 31, 2023 consisted of the following (in thousands, except weighted average data):


	Amortized Cost		Fair Value
Due in one year or less	$	27,865	$	27,528
Weighted average contractual maturity			0.3 years

Amortized cost and fair value of marketable debt securities, available-for-sale by contractual maturity as of December 31, 2022 consisted of the following (in thousands, except weighted average data):


	Amortized Cost		Fair Value
Due in one year or less	$	51,387	$	50,648
Weighted average contractual maturity			0.3 years

Actual maturities may differ from contractual maturities because certain issuers may have the right or obligation to prepay certain obligations with or without penalties.