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Commitments, Contingencies and Off-Balance Sheet Arrangements - Off-Balance Sheet Commitments (Detail) $ in Millions	9 Months Ended
	Sep. 30, 2023 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2023	$ 0.4
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	18.1
Total Amounts Committed	20.9
Financial Guarantees [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - 2023	0.4
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	2.8
Letters of Credit [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Amount of Commitment Expiration by Period - Thereafter	18.1
Total Amounts Committed	$ 18.1

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