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Borrowings and Other Obligations - Federal Home Loan Bank, Funds Lines of Credit and Reserve Bank (Details) - Line of Credit - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
FHLB short-term borrowings |  |
Line of Credit Facility [Line Items] |  |
Lines of credit | $ 948.1 | $ 1,009.0
Federal Funds Purchased | Unsecured Debt |  |
Line of Credit Facility [Line Items] |  |
Lines of credit | 125.0 | 135.0
Federal Reserve Bank of San Francisco | FRBSF short-term borrowings under the BTFP |  |
Line of Credit Facility [Line Items] |  |
Lines of credit | $ 358.0 | 64.0
Federal Reserve Bank Advances | FRBSF short-term borrowings under the BTFP |  |
Line of Credit Facility [Line Items] |  |
Lines of credit |  | $ 270.2

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