Supplementary Balance Sheet Information - Investments Available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Maturity less than 1 year:
Amortized Cost	$ 35,751	$ 26,293
Gross Unrealized Gains	46	33
Gross Unrealized Losses	(12)	(17)
Fair Market Value	35,785	26,309
Maturity 1 to 2 years:
Amortized Cost	8,796	26,942
Gross Unrealized Gains	49	6
Gross Unrealized Losses	(1)	(89)
Fair Market Value	8,844	26,859
Amortized Cost	44,547	53,235
Gross Unrealized Gains	95	39
Gross Unrealized Losses	(13)	(106)
Fair Market Value	44,629	53,168
Certificate of deposit
Maturity less than 1 year:
Amortized Cost	334	8,317
Gross Unrealized Gains	0	16
Gross Unrealized Losses	0	0
Fair Market Value	334	8,333
Corporate debt securities
Maturity less than 1 year:
Amortized Cost	16,213	10,948
Gross Unrealized Gains	36	8
Gross Unrealized Losses	(2)	(16)
Fair Market Value	16,247	10,940
Maturity 1 to 2 years:
Amortized Cost	8,796	8,437
Gross Unrealized Gains	49	6
Gross Unrealized Losses	(1)	(10)
Fair Market Value	8,844	8,433
Commercial paper
Maturity less than 1 year:
Amortized Cost	308	6,193
Gross Unrealized Gains	2	9
Gross Unrealized Losses	0	0
Fair Market Value	310	6,202
U.S. government agencies
Maturity less than 1 year:
Amortized Cost		835
Gross Unrealized Gains		0
Gross Unrealized Losses		(1)
Fair Market Value		834
U.S. treasury securities
Maturity less than 1 year:
Amortized Cost	18,896
Gross Unrealized Gains	8
Gross Unrealized Losses	(10)
Fair Market Value	$ 18,894
Maturity 1 to 2 years:
Amortized Cost		18,505
Gross Unrealized Gains		0
Gross Unrealized Losses		(79)
Fair Market Value		$ 18,426

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