Investments (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Marketable Securities [Line Items]
Amortized Cost	$ 68,608,000		$ 68,608,000		$ 60,909,000
Gains	0		0		0
Losses	(1,146,000)		(1,146,000)		(154,000)
Credit Losses	0		0		0
Estimated Fair Value	67,463,000		$ 67,463,000		$ 60,755,000
Remaining contractual maturity period			3 years		3 years
Impairments of assets	0	$ 0	$ 0	$ 0
Short-term investments
Marketable Securities [Line Items]
Estimated Fair Value	45,724,000		45,724,000		$ 35,068,000
Long-term investments
Marketable Securities [Line Items]
Estimated Fair Value	21,739,000		21,739,000		25,687,000
Commercial paper
Marketable Securities [Line Items]
Amortized Cost	14,736,000		14,736,000		10,243,000
Gains	0		0		0
Losses	(95,000)		(95,000)		(12,000)
Credit Losses	0		0		0
Estimated Fair Value	14,641,000		14,641,000		10,231,000
Corporate notes
Marketable Securities [Line Items]
Amortized Cost	50,893,000		50,893,000		50,666,000
Gains	0		0		0
Losses	(1,048,000)		(1,048,000)		(142,000)
Credit Losses	0		0		0
Estimated Fair Value	49,845,000		49,845,000		$ 50,524,000
U.S. government agency bonds
Marketable Securities [Line Items]
Amortized Cost	2,979,000		2,979,000
Gains	0		0
Losses	(3,000)		(3,000)
Credit Losses	0		0
Estimated Fair Value	$ 2,977,000		$ 2,977,000