Commitments and Contingencies (Detail) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022
Unfunded Loan Commitment, Commitments To Extend Credit
Loss Contingencies [Line Items]
Unfunded loan commitments	$ 108.9	$ 138.0	$ 132.6

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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