Fair Value Measurements and Fair Value of Financial Instruments - Schedule of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Investments:
Fair Value	$ 2,480,352
Fair value, recurring
Cash and cash equivalents:
Amortized Cost	260,862	$ 173,964
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(19)	(5)
Fair Value	260,843	173,959
Investments:
Amortized Cost	2,483,822	2,263,417
Gross Unrealized Gains	1,449	5,372
Gross Unrealized Losses	(4,919)	(125)
Fair Value	2,480,352	2,268,664
Total assets measured at fair value, amortized cost	2,744,684	2,437,381
Total assets measured at fair value, gross unrealized gains	1,449	5,372
Total assets measured at fair value, gross unrealized losses	(4,938)	(130)
Total assets measured at fair value, fair value	2,741,195	2,442,623
Fair value, recurring \| Cash \| Level 1
Cash and cash equivalents:
Amortized Cost	89,150	85,417
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	89,150	85,417
Fair value, recurring \| Money market funds \| Level 1
Cash and cash equivalents:
Amortized Cost	44,366	52,302
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	44,366	52,302
Fair value, recurring \| Commercial paper \| Level 2
Cash and cash equivalents:
Amortized Cost	110,866	36,245
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(17)	(5)
Fair Value	110,849	36,240
Fair value, recurring \| Asset-backed securities \| Level 2
Cash and cash equivalents:
Amortized Cost	16,480
Gross Unrealized Gains	0
Gross Unrealized Losses	(2)
Fair Value	16,478
Investments:
Amortized Cost	142,414	152,164
Gross Unrealized Gains	40	249
Gross Unrealized Losses	(411)	(27)
Fair Value	142,043	152,386
Fair value, recurring \| U.S. Treasury securities \| Level 1
Investments:
Amortized Cost	887,530	945,072
Gross Unrealized Gains	667	1,969
Gross Unrealized Losses	(905)	(40)
Fair Value	887,292	947,001
Fair value, recurring \| Commercial paper \| Level 2
Investments:
Amortized Cost	24,006	28,763
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(1)	0
Fair Value	24,005	28,766
Fair value, recurring \| Corporate debt \| Level 2
Investments:
Amortized Cost	1,178,119	897,564
Gross Unrealized Gains	680	2,862
Gross Unrealized Losses	(3,105)	(30)
Fair Value	1,175,694	900,396
Fair value, recurring \| U.S. government agency securities \| Level 2
Investments:
Amortized Cost	211,753	219,854
Gross Unrealized Gains	62	289
Gross Unrealized Losses	(497)	(28)
Fair Value	211,318	220,115
Fair value, recurring \| Certificate of Deposits \| Level 2
Investments:
Amortized Cost	40,000	20,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 40,000	$ 20,000

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