| Off-Balance Sheet Commitments - Additional Information (Detail) $ in Millions | Mar. 31, 2025  USD ($) | 
|---|---|
| Loss Contingency [Abstract] | |
| Letters of credit to FHLBSF | $ 150.0 | 
| Deposits from State of California | $ 150.0 | 
| X | ||||||||||
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- Definition Federal home loan bank advances general debt obligations disclosure deposits available. No definition available. 
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| X | ||||||||||
| 
- Definition Federal home loan bank advances general debt obligations disclosure letter of credit available. No definition available. 
 | 
| X | ||||||||||
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- References No definition available. 
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