Investment Securities - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Investment securities, available-for-sale	$ 186.0	$ 77.8
Aggregate related fair value of investments with unrealized losses	190.6	165.2
Continuous unrealized loss position, 12 months or longer	0.0	70.1
Continuous unrealized loss position, less than 12 months		95.1
Debt Securities
Debt Securities, Available-for-Sale [Line Items]
Interest receivable	5.0	$ 2.3
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	56.3
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	7.4
Corporate Notes/Bonds
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	$ 126.9

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

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