Off-Balance Sheet Commitments - Additional Information (Detail) $ in Millions	Dec. 31, 2023 USD ($)
Loss Contingencies [Line Items]
Letters of credit to FHLBSF	$ 120.0
Deposits from State of California	$ 120.0

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
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