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Federal Home Loan Bank Advances and Other Borrowings (Narrative) (Details) $ in Billions	Sep. 30, 2025 USD ($)
Debt Instrument [Line Items]
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds	$ 7.7
Subordinated Debt | Subordinated Debt 5.125% Maturing on June 11, 2030
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	5.39%
Federal Reserve Bank Advances
Debt Instrument [Line Items]
Debt Instrument, Unused Borrowing Capacity, Amount	$ 7.1

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