Fair Value Measurements - Schedule of Amortized Cost (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	$ 98,412,000		$ 98,412,000		$ 179,248,000
Gross Unrealized Gains	0		0		13,000
Gross Unrealized Losses	(2,387,000)		(2,387,000)		(4,452,000)
Fair Value	96,025,000		96,025,000		174,809,000
Accrued interest receivable	1,600,000		1,600,000		900,000
Realized gains (losses) on marketable securities	0	$ 0	0	$ 0
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	25,850,000		25,850,000		56,426,000
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	(175,000)		(175,000)		(651,000)
Fair Value	25,675,000		25,675,000		55,775,000
Yankee bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	2,605,000		2,605,000		5,358,000
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	(37,000)		(37,000)		(92,000)
Fair Value	2,568,000		2,568,000		5,266,000
Agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	6,041,000		6,041,000		12,485,000
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	(98,000)		(98,000)		(116,000)
Fair Value	5,943,000		5,943,000		12,369,000
Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	12,731,000		12,731,000		12,841,000
Gross Unrealized Gains	0		0		0
Gross Unrealized Losses	(828,000)		(828,000)		(1,030,000)
Fair Value	11,903,000		11,903,000		11,811,000
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	2,973,000		2,973,000		2,846,000
Gross Unrealized Gains	0		0		8,000
Gross Unrealized Losses	0		0		0
Fair Value	2,973,000		2,973,000		2,854,000
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	9,235,000		9,235,000		25,544,000
Gross Unrealized Gains	0		0		2,000
Gross Unrealized Losses	(90,000)		(90,000)		(427,000)
Fair Value	9,145,000		9,145,000		25,119,000
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost	38,977,000		38,977,000		63,748,000
Gross Unrealized Gains	0		0		3,000
Gross Unrealized Losses	(1,159,000)		(1,159,000)		(2,136,000)
Fair Value	$ 37,818,000		$ 37,818,000		$ 61,615,000