Assets - Available-For-Sale Securities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Total available-for-sale securities
Amortized Cost	$ 130,325		$ 148,483
Gross Unrealized Gains	5
Gross Unrealized Losses	(213)		(995)
Estimated Fair Value	130,117		147,488
Available-for-sale securities in a loss position
Investments, Continuous loss position for less than 12 months, Estimated Fair Value	107,256		82,012
Investments, Continuous loss position for less than 12 months, Gross Unrealized Losses	(170)		(308)
Investments, Continuous loss position for 12 months or more, Estimated Fair Value	5,581		49,793
Investments, Continuous loss position for 12 months or more, Gross Unrealized Losses	(43)		(687)
Contractual maturities - Amortized Cost
Amortized Cost, Due in one year or less	116,504
Amortized Cost, Due after one year through two years	13,821
Amortized Cost	130,325		148,483
Contractual maturities - Estimated Fair Value
Estimated Fair Value, Due in one year or less	116,351
Estimated Fair Value, Due after one year through two years	13,766
Available-for-sale Securities, Debt Securities, Total	130,117		147,488
Realized gains or losses
Realized gains or losses	0	$ 0
Unrealized losses	0	$ 0
U.S. treasuries
Total available-for-sale securities
Amortized Cost	23,900		63,331
Gross Unrealized Losses	(14)		(482)
Estimated Fair Value	23,886		62,849
Available-for-sale securities in a loss position
Investments, Continuous loss position for less than 12 months, Estimated Fair Value	20,892		39,791
Investments, Continuous loss position for less than 12 months, Gross Unrealized Losses	(8)		(84)
Investments, Continuous loss position for 12 months or more, Estimated Fair Value	2,994		23,057
Investments, Continuous loss position for 12 months or more, Gross Unrealized Losses	(6)		(398)
Contractual maturities - Amortized Cost
Amortized Cost	23,900		63,331
Contractual maturities - Estimated Fair Value
Available-for-sale Securities, Debt Securities, Total	23,886		62,849
Government agency securities
Total available-for-sale securities
Amortized Cost	69,345		27,464
Gross Unrealized Losses	(144)		(98)
Estimated Fair Value	69,201		27,366
Available-for-sale securities in a loss position
Investments, Continuous loss position for less than 12 months, Estimated Fair Value	69,201		22,528
Investments, Continuous loss position for less than 12 months, Gross Unrealized Losses	(144)		(86)
Investments, Continuous loss position for 12 months or more, Estimated Fair Value			4,838
Investments, Continuous loss position for 12 months or more, Gross Unrealized Losses			(12)
Contractual maturities - Amortized Cost
Amortized Cost	69,345		27,464
Contractual maturities - Estimated Fair Value
Available-for-sale Securities, Debt Securities, Total	69,201		27,366
Corporate debt
Total available-for-sale securities
Amortized Cost	20,281		42,006
Gross Unrealized Gains	5
Gross Unrealized Losses	(55)		(415)
Estimated Fair Value	20,231		41,591
Available-for-sale securities in a loss position
Investments, Continuous loss position for less than 12 months, Estimated Fair Value	17,163		19,693
Investments, Continuous loss position for less than 12 months, Gross Unrealized Losses	(18)		(138)
Investments, Continuous loss position for 12 months or more, Estimated Fair Value	2,587		21,898
Investments, Continuous loss position for 12 months or more, Gross Unrealized Losses	(37)		(277)
Contractual maturities - Amortized Cost
Amortized Cost	20,281		42,006
Contractual maturities - Estimated Fair Value
Available-for-sale Securities, Debt Securities, Total	20,231		41,591
Commercial paper
Total available-for-sale securities
Amortized Cost	16,799		15,682
Estimated Fair Value	16,799		15,682
Contractual maturities - Amortized Cost
Amortized Cost	16,799		15,682
Contractual maturities - Estimated Fair Value
Available-for-sale Securities, Debt Securities, Total	$ 16,799		$ 15,682