Commitments, Contingencies and Off-Balance Sheet Arrangements - Off-Balance Sheet Commitments (Detail) $ in Millions	3 Months Ended
Mar. 31, 2024 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2024	$ 1.4
Amount of Commitment Expiration by Period - 2025	0.2
Amount of Commitment Expiration by Period - 2026	0.1
Amount of Commitment Expiration by Period - 2027	0.1
Amount of Commitment Expiration by Period - Thereafter	23.7
Total Amounts Committed	25.5
Financial Guarantees [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2024	1.4
Amount of Commitment Expiration by Period - 2025	0.2
Amount of Commitment Expiration by Period - 2026	0.1
Amount of Commitment Expiration by Period - 2027	0.1
Total Amounts Committed	1.8
Letters of Credit [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - Thereafter	23.7
Total Amounts Committed	$ 23.7

Amount of Commitment Expiration Off-Balance Sheet Commitments

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Amount of Commitment Expiration Off-Balance Sheet Commitments Within Year Four

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Amount of Commitment Expiration Off-Balance Sheet Commitments Within Year One

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Amount of Commitment Expiration Off-Balance Sheet Commitments Within Year Thereafter

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Amount of Commitment Expiration Off-Balance Sheet Commitments Within Year Three

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Amount of Commitment Expiration Off-Balance Sheet Commitments Within Year Two

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Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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