Fair Value Measurements, Cash Equivalents and Marketable Securities - Measured on Recurring Basis (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financial Assets:
Cash equivalents	$ 646,884	$ 590,026
U.S. government debt securities		314,438
Total financial assets		904,464
Financial Liabilities:
Contingent consideration	2,885	6,050
Total financial liabilities	2,885	6,050
Level 1
Financial Assets:
Cash equivalents	355	57,151
U.S. government debt securities		0
Total financial assets		57,151
Financial Liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 2
Financial Assets:
Cash equivalents	646,529	532,875
U.S. government debt securities		314,438
Total financial assets		847,313
Financial Liabilities:
Contingent consideration	0	0
Total financial liabilities	0	0
Level 3
Financial Assets:
Cash equivalents	0	0
U.S. government debt securities		0
Total financial assets		0
Financial Liabilities:
Contingent consideration	2,885	6,050
Total financial liabilities	2,885	6,050
U.S. government debt securities
Financial Assets:
U.S. government debt securities		314,438
U.S. government debt securities \| Level 1
Financial Assets:
U.S. government debt securities		0
U.S. government debt securities \| Level 2
Financial Assets:
U.S. government debt securities		314,438
U.S. government debt securities \| Level 3
Financial Assets:
U.S. government debt securities		0
Money market funds
Financial Assets:
Cash equivalents	355	57,151
Money market funds \| Level 1
Financial Assets:
Cash equivalents	355	57,151
Money market funds \| Level 2
Financial Assets:
Cash equivalents	0	0
Money market funds \| Level 3
Financial Assets:
Cash equivalents	0	0
Income deposit funds
Financial Assets:
Cash equivalents	106,742	103,581
Income deposit funds \| Level 1
Financial Assets:
Cash equivalents	0	0
Income deposit funds \| Level 2
Financial Assets:
Cash equivalents	106,742	103,581
Income deposit funds \| Level 3
Financial Assets:
Cash equivalents	0	0
U.S. government debt securities
Financial Assets:
Cash equivalents	539,787	429,294
U.S. government debt securities \| Level 1
Financial Assets:
Cash equivalents	0	0
U.S. government debt securities \| Level 2
Financial Assets:
Cash equivalents	539,787	429,294
U.S. government debt securities \| Level 3
Financial Assets:
Cash equivalents	$ 0	$ 0

Fair value portion of asset recognized for present right to economic benefit.

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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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Fair value of financial and nonfinancial obligations.

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