Marketable Securities - Summary of Cash Equivalents and Marketable Securities Recorded at Fair Value (Detail) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Marketable Securities [Line Items]
Cash equivalents, amortized cost	$ 296,570	$ 191,721
Cash equivalents, gross unrealized gains	0	0
Cash equivalents, gross unrealized losses	(58)	0
Cash equivalents, fair value	296,512	191,721
Marketable securities, amortized cost	1,531,204	1,304,304
Marketable securities, gross unrealized gains	691	3,821
Marketable securities, gross unrealized losses	(3,532)	(1,937)
Marketable securities, fair value	1,528,363	1,306,188
Cash equivalents and marketable securities, amortized cost	1,827,774	1,496,025
Cash equivalents and marketable securities, gross unrealized gains	691	3,821
Cash equivalents and marketable securities, gross unrealized losses	(3,590)	(1,937)
Cash equivalents and marketable securities, fair value	1,824,875	1,497,909
Money Market Funds [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	139,868	185,990
Cash equivalents, gross unrealized gains	0	0
Cash equivalents, gross unrealized losses	0	0
Cash equivalents, fair value	139,868	185,990
Certificates and Term Deposits [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	25,351
Cash equivalents, gross unrealized gains	0
Cash equivalents, gross unrealized losses	0
Cash equivalents, fair value	25,351
Marketable securities, amortized cost	132,499	47,282
Marketable securities, gross unrealized gains	0	0
Marketable securities, gross unrealized losses	0	0
Marketable securities, fair value	132,499	47,282
Commercial Paper [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	125,953
Cash equivalents, gross unrealized gains	0
Cash equivalents, gross unrealized losses	(58)
Cash equivalents, fair value	125,895
Marketable securities, amortized cost	130,273	155,403
Marketable securities, gross unrealized gains	0	32
Marketable securities, gross unrealized losses	(79)	(26)
Marketable securities, fair value	130,194	155,409
US Treasury Securities [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	3,974	5,731
Cash equivalents, gross unrealized gains	0	0
Cash equivalents, gross unrealized losses	0	0
Cash equivalents, fair value	3,974	5,731
Marketable securities, amortized cost	11,883	22,963
Marketable securities, gross unrealized gains	0	45
Marketable securities, gross unrealized losses	(9)	0
Marketable securities, fair value	11,874	23,008
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	1,424
Cash equivalents, gross unrealized gains	0
Cash equivalents, gross unrealized losses	0
Cash equivalents, fair value	1,424
Marketable securities, amortized cost	1,013,028	883,550
Marketable securities, gross unrealized gains	669	3,367
Marketable securities, gross unrealized losses	(2,517)	(1,559)
Marketable securities, fair value	1,011,180	885,358
Government-sponsored Enterprise Securities [Member]
Marketable Securities [Line Items]
Marketable securities, amortized cost	243,521	195,106
Marketable securities, gross unrealized gains	22	377
Marketable securities, gross unrealized losses	(927)	(352)
Marketable securities, fair value	$ 242,616	$ 195,131

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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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