Junior Subordinated Debt Securities (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	three-month CME Term SOFR plus 0.26161%
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 101	$ 108
Interest Expense, Junior Subordinated Debentures	261	261	$ 261
Senior notes
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 99	106
Debt Instrument, Interest Rate, Stated Percentage	5.70%
Junior Subordinated Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 3,200	3,200
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	36	39
Junior Subordinated Debt Instrument One [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	500	500
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 5	5
Debt Instrument, Interest Rate, Stated Percentage	10.75%
Junior Subordinated Debt Instrument Four [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 1,250	1,250
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 13	14
Debt Instrument, Interest Rate, Stated Percentage	6.40%
Junior Subordinated Debt Instrument Three [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 700	700
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 11	12
Debt Instrument, Interest Rate, Stated Percentage	7.875%
Junior Subordinated Debt Instrument Two [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 750	750
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 7	$ 8
Debt Instrument, Interest Rate, Stated Percentage	9.25%

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