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Medium- And Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021
Debt Instrument [Line Items] |  |
Fixed-to-floating rate subordinated notes | $ 500 |
Fair value fixed-to-floating rate swap | 2.67% |
Unamortized debt issuance costs | $ 9 | $ 7
Subsidiaries |  |
Debt Instrument [Line Items] |  |
Long-term Federal Home Loan Bank advances | $ 0 | $ 0
5.332% subordinated notes due 2033 | Subsidiaries |  |
Debt Instrument [Line Items] |  |
Debt Instrument, Maturity Year | 2033 |
Stated interest rate | 5.332% |

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