Investment Securities - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Investment securities, available for sale, noncurrent	$ 164.0	$ 77.8
Aggregate related fair value of investments with unrealized losses	66.2	165.2
Aggregate fair value of investments with unrealized losses	1.0	70.1
Continuous unrealized losses, value remaining	65.2	95.1
Debt Securities
Debt Securities, Available-for-Sale [Line Items]
Accrued interest receivable	3.7	$ 2.3
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	30.5
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	6.0
Corporate Notes/Bonds
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	$ 29.7

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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