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Loans and Allowance for Credit Losses on Loans - Pledged Loans (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
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Other residential | Federal Reserve Bank |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Collateral pledged | $ 101.1 | $ 110.0
Federal Home Loan Bank of San Francisco |  |
Financial Instruments Owned and Pledged as Collateral [Line Items] |  |
Collateral pledged | $ 1,372.0 | $ 1,351.0

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