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Equity (Schedule of Reclassifications out of AOCI) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Income Tax Expense (Benefit) |  | $ (65) | $ (56) | $ (306) | $ (181)
Net income |  | 253 | 156 | 719 | 569
Unrealized Appreciation Depreciation Of Investments [Member] |  |  |  |  |
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Investment related gains (losses), net |  | 8 | (68) | (127) | (356)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest |  | (8) | (85) | (175) | (389)
Income Tax Expense (Benefit) |  | (9) | 18 | 25 | 79
Net income |  | (17) | (67) | (150) | (310)
Amortization Of Unrealized Pension And Postretirement Benefits [Member] |  |  |  |  |
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Prior service cost | [1] | 0 | 0 | 1 | 1
Actuarial gains/(losses) | [1] | (1) | (1) | (1) | (2)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest |  | (1) | (1) | 0 | (1)
Income Tax Expense (Benefit) |  | 0 | 0 | 0 | 0
Net income |  | (1) | (1) | 0 | (1)
Amounts Reclassified From AOCI [Member] |  |  |  |  |
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Net income |  | (18) | (68) | (150) | (311)
Currency Swap [Member] | Unrealized Appreciation Depreciation Of Investments [Member] | Unrealized Gains Losses On Available For Sale Securities [Member] |  |  |  |  |
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI | [2] | (17) | (20) | (51) | (42)
Interest Rate Options [Member] | Unrealized Appreciation Depreciation Of Investments [Member] | Unrealized Gains Losses On Available For Sale Securities [Member] |  |  |  |  |
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |
Cash Flow Derivative Gains Losses Reclassified Into Income From AOCI | [2] | $ 1 | $ 3 | $ 3 | $ 9
[1] | This AOCI component is included in the computation of the net periodic pension cost. See Note 14 – “Employee Benefit Plans” for additional details.
[2] | See Note 11 – “Derivative Instruments” for additional information on cash flow hedges.

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