Fair Value Measurements and Fair Value of Financial Instruments - Schedule of Financial Instruments Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Abstract]
Fair Value	$ 1,333,270
Fair value, recurring
Cash and Cash Equivalents [Abstract]
Amortized Cost	518,842	$ 397,616
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(172)	(165)
Fair Value	518,670	397,451
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	1,335,365	845,109
Gross Unrealized Gains	124	615
Gross Unrealized Losses	(2,219)	(273)
Fair Value	1,333,270	845,451
Total assets measured at fair value, amortized cost	1,854,207	1,242,725
Total assets measured at fair value, gross unrealized gains	124	615
Total assets measured at fair value, gross unrealized losses	(2,391)	(438)
Total assets measured at fair value, fair value	1,851,940	1,242,902
Fair value, recurring \| Cash \| Level 1
Cash and Cash Equivalents [Abstract]
Amortized Cost	41,651	50,003
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	41,651	50,003
Fair value, recurring \| Money market funds \| Level 1
Cash and Cash Equivalents [Abstract]
Amortized Cost	96,932	47,357
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	96,932	47,357
Fair value, recurring \| U.S. Treasury securities \| Level 1
Cash and Cash Equivalents [Abstract]
Amortized Cost	4,964
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair Value	4,964
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	674,993	481,704
Gross Unrealized Gains	50	422
Gross Unrealized Losses	(1,082)	(44)
Fair Value	673,961	482,082
Fair value, recurring \| Commercial paper \| Level 2
Cash and Cash Equivalents [Abstract]
Amortized Cost	327,252	300,256
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(170)	(165)
Fair Value	327,082	300,091
Fair value, recurring \| Commercial paper \| Level 2
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	104,229	102,435
Gross Unrealized Gains	0	7
Gross Unrealized Losses	(61)	(35)
Fair Value	104,168	102,407
Fair value, recurring \| U.S. government agency securities \| Level 2
Cash and Cash Equivalents [Abstract]
Amortized Cost	48,043
Gross Unrealized Gains	0
Gross Unrealized Losses	(2)
Fair Value	48,041
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	121,175	103,484
Gross Unrealized Gains	11	0
Gross Unrealized Losses	(209)	(152)
Fair Value	120,977	103,332
Fair value, recurring \| Corporate debt \| Level 2
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	323,913	133,523
Gross Unrealized Gains	41	168
Gross Unrealized Losses	(817)	(42)
Fair Value	323,137	133,649
Fair value, recurring \| Asset-backed securities \| Level 2
Debt Securities, Available-for-Sale [Abstract]
Amortized Cost	111,055	23,963
Gross Unrealized Gains	22	18
Gross Unrealized Losses	(50)	0
Fair Value	$ 111,027	$ 23,981

Cash and cash equivalents amortized cost.

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Cash and cash equivalents and investments.

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Cash and cash equivalents and investments amortized cost basis.

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Cash and cash equivalents and investments gross unrealized gain before tax.

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Cash and cash equivalents and investments gross unrealized loss before tax.

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Cash and cash equivalents gross unrealized gain before tax.

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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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Amount, before tax, of unrealized loss 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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Amortized cost of 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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Amount of 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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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