Fair Value Measurements - Summary of Fair Value And Unrealized Losses of Marketable Securities In Loss Position (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	$ 1,096,780	$ 1,224,715
Less than 12 months, Unrealized Losses	(13,352)	(2,687)
Greater than 12 months, Fair Value	49,884
Greater than 12 months, Unrealized Losses	(542)
Fair Value	1,146,664	1,224,715
Unrealized Losses	(13,894)	(2,687)
U.S. Government Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	400,161	309,588
Less than 12 months, Unrealized Losses	(5,843)	(982)
Fair Value	400,161	309,588
Unrealized Losses	(5,843)	(982)
U.S. Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	449,691	601,475
Less than 12 months, Unrealized Losses	(4,471)	(1,083)
Greater than 12 months, Fair Value	27,924
Greater than 12 months, Unrealized Losses	(344)
Fair Value	477,615	601,475
Unrealized Losses	(4,815)	(1,083)
International Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	145,479	231,672
Less than 12 months, Unrealized Losses	(1,940)	(491)
Greater than 12 months, Fair Value	21,960
Greater than 12 months, Unrealized Losses	(198)
Fair Value	167,439	231,672
Unrealized Losses	(2,138)	(491)
U.S. Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	30,689	21,968
Less than 12 months, Unrealized Losses	(133)	(18)
Fair Value	30,689	21,968
Unrealized Losses	(133)	(18)
International Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	36,487	35,059
Less than 12 months, Unrealized Losses	(253)	(23)
Fair Value	36,487	35,059
Unrealized Losses	(253)	(23)
U.S. Municipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Value	34,273	24,953
Less than 12 months, Unrealized Losses	(712)	(90)
Fair Value	34,273	24,953
Unrealized Losses	$ (712)	$ (90)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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