Medium- And Long-Term Debt (Schedule Of Medium- And Long-Term Debt) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Medium- and long-term notes	$ 1,503	$ 523
Medium- and long-term debt	6,673	6,206
Parent Company
Debt Instrument [Line Items]
Medium- and long-term debt	1,746	764
Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	953	965
Medium- and long-term notes	0	489
Long-term Federal Home Loan Bank advances	3,974	3,988
Medium- and long-term debt	4,927	5,442
3.80% subordinated notes due 2026 \| Parent Company
Debt Instrument [Line Items]
Subordinated notes	$ 243	241
Stated interest rate	3.80%
Maturity Year	2026
4.00% notes due 2029 \| Parent Company
Debt Instrument [Line Items]
Medium- and long-term notes	$ 519	523
Stated interest rate	4.00%
Maturity Year	2029
5.982% Notes Due 2030 \| Parent Company
Debt Instrument [Line Items]
Medium- and long-term notes	$ 984	0
Stated interest rate	5.982%
Maturity Year	2030
4.00% subordinated Notes Due 2025 \| Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	$ 345	337
Stated interest rate	4.00%
Maturity Year	2025
7.875% subordinated Notes Due 2026 \| Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	$ 157	162
Stated interest rate	7.875%
Maturity Year	2026
5.332% Subordinated Note Due 2033 \| Subsidiaries
Debt Instrument [Line Items]
Subordinated notes	$ 451	466
Stated interest rate	5.332%
Maturity Year	2033
2.50% notes due 2024 \| Subsidiaries
Debt Instrument [Line Items]
Medium- and long-term notes	$ 0	489
Stated interest rate	2.50%
Maturity Year	2024
5.07% Advance Due 2025 \| Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank advances	$ 1,000	995
Stated interest rate	5.07%
Maturity Year	2025
4.79% Advance Due 2026 \| Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank advances	$ 997	997
Stated interest rate	4.79%
Maturity Year	2026
4.49% Advance Due 2027 \| Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank advances	$ 992	999
Stated interest rate	4.49%
Maturity Year	2027
4.49% Advance Due 2028 \| Subsidiaries
Debt Instrument [Line Items]
Long-term Federal Home Loan Bank advances	$ 985	$ 997
Stated interest rate	4.49%
Maturity Year	2028

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