Cash Equivalents and Marketable Securities - Schedule of Fair Value and Amortized Cost of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Marketable Securities [Line Items]
Amortized Cost	$ 116,311	$ 293,828	$ 393,504
Amortized Cost	738,995	876,356
Gross Unrealized Gains	3	4
Gross Unrealized Losses	(9,999)	(1,627)
Fair Value	728,999	874,733
Classified as:
Cash equivalents	94,659	270,236
Marketable securities	531,821	320,966
Marketable securities, non-current	102,519	283,531
Total cash equivalents and marketable securities	728,999	874,733
U.S. Treasury securities
Marketable Securities [Line Items]
Amortized Cost	313,281	290,909
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(6,972)	(1,205)
Fair Value	306,309	289,706
U.S. government agency securities
Marketable Securities [Line Items]
Amortized Cost	147,357	93,864
Gross Unrealized Gains	2	2
Gross Unrealized Losses	(1,716)	(240)
Fair Value	145,643	93,626
Corporate debt securities
Marketable Securities [Line Items]
Amortized Cost	235,749	285,338
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(1,311)	(182)
Fair Value	234,439	285,156
Money market funds
Marketable Securities [Line Items]
Amortized Cost	42,608	206,245
Fair Value	$ 42,608	$ 206,245

Cash Equivalents And Debt Securities, Available-For-Sale

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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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