Marketable Securities

3 Months Ended

Mar. 31, 2024

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

3. Marketable Securities

The amortized cost and estimated fair value of marketable securities, by contractual maturity, are as follows:

	March 31, 2024
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Maturing in one year or less
U.S. Treasury Bill	$	8,924	$	—	$	(1	)	$	8,923
U.S. Treasuries		43,758		—		(35	)		43,723
Maturing after one year through five years
U.S. Treasuries		9,920		—		(51	)		9,869
Total	$	62,602	$	—	$	(87	)	$	62,515

	December 31, 2023
(in thousands)	Amortized Cost		Gross Unrealized Holding Gains		Gross Unrealized Holding Losses			Fair Value
Maturing in one year or less
U.S. Treasury Bill	$	8,806	$	6	$	—		$	8,812
U.S. Treasuries		97,086		12		(95	)		97,003
Total	$	105,892	$	18	$	(95	)	$	105,815

The following tables summarize the fair value and gross unrealized losses aggregated by category and the length of time that individual securities have been in an unrealized loss position:

	March 31, 2024
	Less than twelve months					Greater than twelve months					Total
(in thousands)	Fair value		Unrealized loss			Fair value		Unrealized loss			Fair value		Unrealized loss
U.S. Treasury Bill	$	8,923	$	(1	)	$	—	$	—		$	8,923	$	(1	)
U.S. Treasuries		26,762		(53	)		26,830		(33	)		53,592		(86	)
Total	$	35,685	$	(54	)	$	26,830	$	(33	)	$	62,515	$	(87	)

	December 31, 2023
	Less than twelve months				Greater than twelve months					Total
(in thousands)	Fair value		Unrealized loss		Fair value		Unrealized loss			Fair value		Unrealized loss
U.S. Treasuries	$	—	$	—	$	53,447	$	(95	)	$	53,447	$	(95	)
Total	$	—	$	—	$	53,447	$	(95	)	$	53,447	$	(95	)

The Company holds investment grade marketable securities considered to be in an unrealized loss position. Although these marketable securities are held at an unrealized loss position at March 31, 2024, the Company does not intend to sell the marketable securities prior to the value of the securities being recovered, and the Company has concluded that it is more likely than not that the marketable securities cost basis values will be recovered prior to sale of the securities and that there are no conditions or events that might require the Company to sell the securities before recovery of the cost basis occurs. Further, the Company did not record any impairments to marketable securities or reserves for credit losses related to its marketable debt securities during the periods presented.