Commitments, Contingencies and Off-Balance Sheet Arrangements - Off-Balance Sheet Commitments (Detail) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2024	$ 2.0
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	21.2
Total Amounts Committed	23.6
Financial Guarantees [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2024	2.0
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	2.4
Letters of Credit [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - Thereafter	21.2
Total Amounts Committed	$ 21.2

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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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