Investment Securities - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Investment securities, available-for-sale	$ 77.8	$ 71.5
Aggregate related fair value of investments with unrealized losses	165.2	438.3
Continuous unrealized loss position, less than 12 months	95.1	389.2
Continuous unrealized loss position, 12 months or longer	70.1	49.1
Cash and Cash Equivalents
Debt Securities, Available-for-Sale [Line Items]
Certificates of deposit, at carrying value	60.0	7.5
US government agencies securities, at carrying value	2.5	$ 20.5
U.S. Government Agency Securities
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	78.0
Commercial Paper
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	32.1
Corporate Notes/Bonds
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	51.4
Certificates of Deposit
Debt Securities, Available-for-Sale [Line Items]
Aggregate related fair value of investments with unrealized losses	$ 3.7

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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