Fair Value Measurements - Schedule of Amortized Cost (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		$ 178,808,000	$ 199,464,000
Gross Unrealized Gains		1,000	22,000
Gross Unrealized Losses		(3,275,000)	(923,000)
Fair Value		175,534,000	198,563,000
Accrued interest receivable		400,000	600,000
Realized gains (losses) on marketable securities	$ 0
U.S. Treasury securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		51,190,000	52,791,000
Gross Unrealized Gains		0	11,000
Gross Unrealized Losses		(610,000)	(138,000)
Fair Value		50,580,000	52,664,000
Yankee bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		8,031,000	6,175,000
Gross Unrealized Gains		0	1,000
Gross Unrealized Losses		(76,000)	(16,000)
Fair Value		7,955,000	6,160,000
Agency bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		7,020,000	17,546,000
Gross Unrealized Gains		0	0
Gross Unrealized Losses		(49,000)	(16,000)
Fair Value		6,971,000	17,530,000
Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		12,403,000	12,440,000
Gross Unrealized Gains		0	0
Gross Unrealized Losses		(711,000)	(211,000)
Fair Value		11,692,000	12,229,000
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		9,185,000	17,694,000
Gross Unrealized Gains		0	0
Gross Unrealized Losses		0	(4,000)
Fair Value		9,185,000	17,690,000
Asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		28,364,000	27,620,000
Gross Unrealized Gains		0	1,000
Gross Unrealized Losses		(311,000)	(86,000)
Fair Value		28,053,000	27,535,000
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Amortized Cost		62,615,000	65,198,000
Gross Unrealized Gains		1,000	9,000
Gross Unrealized Losses		(1,518,000)	(452,000)
Fair Value		$ 61,098,000	$ 64,755,000