Investments - Amortized Cost (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Cost	$ 486,382	$ 419,783
Gross Unrealized Gains	0	14
Gross Unrealized Losses	(5,989)	(922)
Fair Value	480,393	418,875
Included in cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Cost	9,996	950
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Fair Value	9,995	950
Included in marketable securities
Debt Securities, Available-for-sale [Line Items]
Cost	476,386	418,833
Gross Unrealized Gains	0	14
Gross Unrealized Losses	(5,988)	(922)
Fair Value	470,398	417,925
U.S. treasury securities
Debt Securities, Available-for-sale [Line Items]
Cost	210,786	161,938
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(3,684)	(474)
Fair Value	207,102	161,465
U.S. agency and government sponsored securities
Debt Securities, Available-for-sale [Line Items]
Cost	4,998	4,995
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(117)	(25)
Fair Value	4,881	4,970
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost	123,984	40,788
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(306)	(4)
Fair Value	123,678	40,784
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Cost	125,521	165,522
Gross Unrealized Gains	0	13
Gross Unrealized Losses	(1,676)	(345)
Fair Value	123,845	165,190
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Cost	21,093	46,540
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(206)	(74)
Fair Value	$ 20,887	$ 46,466

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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