Cash Equivalents and Marketable Securities - Schedule of Fair Value and Amortized Cost of Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
Marketable Securities [Line Items]
Amortized Cost	$ 222,596	$ 293,828	$ 244,370
Amortized Cost	836,311	876,356
Gross Unrealized Gains	6	4
Gross Unrealized Losses	(6,606)	(1,627)
Fair Value	829,711	874,733
Classified as:
Cash equivalents	214,277	270,236
Marketable securities	391,316	320,966
Marketable securities, non-current	224,118	283,531
Total cash equivalents and marketable securities	829,711	874,733
U.S. Treasury securities
Marketable Securities [Line Items]
Amortized Cost	315,497	290,909
Gross Unrealized Gains	5	2
Gross Unrealized Losses	(4,877)	(1,205)
Fair Value	310,625	289,706
U.S. government agency securities
Marketable Securities [Line Items]
Amortized Cost	153,149	93,864
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(964)	(240)
Fair Value	152,185	93,626
Corporate debt securities
Marketable Securities [Line Items]
Amortized Cost	263,823	285,338
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(765)	(182)
Fair Value	263,059	285,156
Money market funds
Marketable Securities [Line Items]
Amortized Cost	103,842	206,245
Fair Value	$ 103,842	$ 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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