Supplementary Balance Sheet Information - Investments Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Maturity less than 1 year:
Amortized Cost	$ 33,224	$ 26,293
Gross Unrealized Gains	10	33
Gross Unrealized Losses	(111)	(17)
Fair Market Value	33,123	26,309
Maturity 1 to 2 years:
Amortized Cost	1,690	26,942
Gross Unrealized Gains	5	6
Gross Unrealized Losses	0	(89)
Fair Market Value	1,695	26,859
Amortized Cost	34,914	53,235
Gross Unrealized Gains	15	39
Gross Unrealized Losses	(111)	(106)
Fair Market Value	34,818	53,168
Certificate of deposit
Maturity less than 1 year:
Amortized Cost	5,943	8,317
Gross Unrealized Gains	3	16
Gross Unrealized Losses	0	0
Fair Market Value	5,946	8,333
Corporate debt securities
Maturity less than 1 year:
Amortized Cost	12,175	10,948
Gross Unrealized Gains	7	8
Gross Unrealized Losses	(28)	(16)
Fair Market Value	12,154	10,940
Maturity 1 to 2 years:
Amortized Cost	1,690	8,437
Gross Unrealized Gains	5	6
Gross Unrealized Losses	0	(10)
Fair Market Value	1,695	8,433
Commercial paper
Maturity less than 1 year:
Amortized Cost	2,399	6,193
Gross Unrealized Gains	0	9
Gross Unrealized Losses	0	0
Fair Market Value	2,399	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	12,707	0
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(83)	0
Fair Market Value	12,624	0
Maturity 1 to 2 years:
Amortized Cost	0	18,505
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	(79)
Fair Market Value	$ 0	$ 18,426

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