Cash Equivalents and Marketable Securities

3 Months Ended

Mar. 31, 2024

Cash and Cash Equivalents [Abstract]

Cash Equivalents and Marketable Securities

The fair value and amortized cost of cash equivalents and fixed income marketable securities by major security type are as follows (in thousands):


	March 31, 2024
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	50,808	$	—	$	—	$	50,808
U.S. Treasury securities	343,389		2		(197)		343,194
U.S. government agency securities	38,566		—		(139)		38,427
Corporate debt securities	68,752		—		(70)		68,682
Total cash equivalents and fixed income marketable securities	$	501,515	$	2	$	(406)	$	501,111


Classified as:	Fair Value
Cash equivalents	$	101,996
Marketable securities	399,115
Marketable securities, non-current	—
Total cash equivalents and fixed income marketable securities	$	501,111


	December 31, 2023
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market funds	$	62,075	$	—	$	—	$	62,075
U.S. Treasury securities	374,214		237		(95)		374,356
U.S. government agency securities	48,924		3		(177)		48,750
Corporate debt securities	59,668		—		(62)		59,606
Total cash equivalents and fixed income marketable securities	$	544,881	$	240	$	(334)	$	544,787


Classified as:	Fair Value
Cash equivalents	$	127,705
Marketable securities	400,576
Marketable securities, non-current	16,506
Total cash equivalents and fixed income marketable securities	$	544,787

The fair values of money market and fixed income marketable securities held by the Company in an unrealized loss position for less than 12 months were $358.6 million and $117.8 million as of March 31, 2024 and December 31, 2023, respectively. The fair values of money market and fixed income marketable securities held by the Company in an unrealized loss position for greater than 12 months were $11.5 million and $43.6 million as of March 31, 2024 and December 31, 2023, respectively. As of March 31, 2024 and December 31, 2023, all of the Company’s money market and fixed income marketable securities had a maturity date of two years or less, were available for use and were classified as available‑for‑sale. The Company does not intend to sell these securities nor does the Company believe that it will be required to sell these securities before recovery of their amortized cost basis. The Company determined that there was no material change in the credit risk of the above investments as of both March 31, 2024 and December 31, 2023. As such, an allowance for credit losses has not been recognized. Gross realized gains and losses were de minimis for the three months ended March 31, 2024 and 2023 and as a result, amounts reclassified out of accumulated other comprehensive loss for the three months ended March 31, 2024 and 2023 were also de minimis. See Note 6, Fair Value Measurements, for additional information regarding cash equivalents and fixed income marketable securities.