Marketable Securities - Summary of Available-for-sale Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Marketable Securities [Line Items]
Amortized Cost	$ 1,410,263	$ 1,286,225
Unrealized Gain	23	80
Unrealized Losses	(10,963)	(2,832)
Fair Value	1,399,323	1,283,473
Commercial debt securities
Marketable Securities [Line Items]
Amortized Cost	1,039,451	1,034,573
Unrealized Gain	12	43
Unrealized Losses	(9,325)	(2,564)
Fair Value	1,030,138	1,032,052
Certificates of deposit
Marketable Securities [Line Items]
Amortized Cost	37,908	14,574
Unrealized Gain	10	5
Unrealized Losses	(103)	(10)
Fair Value	37,815	14,569
U.S. government treasury securities
Marketable Securities [Line Items]
Amortized Cost	98,501	77,628
Unrealized Gain	0	18
Unrealized Losses	(895)	(204)
Fair Value	97,606	77,442
Commercial paper
Marketable Securities [Line Items]
Amortized Cost	226,354	151,379
Unrealized Gain	1	14
Unrealized Losses	(581)	(37)
Fair Value	225,774	151,356
Non-U.S. government securities
Marketable Securities [Line Items]
Amortized Cost	8,049	8,071
Unrealized Gain	0	0
Unrealized Losses	(59)	(17)
Fair Value	$ 7,990	$ 8,054

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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