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Investments (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Gain (Loss) on Securities [Line Items] |  |  |
Non-income producing fixed maturity securities | $ 0 | $ 0 |
Investments that exceed ten percent of stockholders' equity | 0 | 0 |
Investment and derivative, realized gain (loss), coinsurance agreement |  |  | $ 18,000,000
Gross gains | 48,000,000 | 75,000,000 | 120,000,000
Debt securities, available-for-sale, realized loss | 150,000,000 | 166,000,000 | 261,000,000
Mortgage loan losses due to changes in expected credit losses | 0 | 11,000,000 | $ 8,000,000
Limited partnership investments | 2,520,000,000 | 2,174,000,000 |
Undistributed earnings of limited partnership investments | $ 334,000,000 | $ 250,000,000 |
Percentage of limited partnerships reported on a current basis | 14.00% |  |
Percentage of limited partnerships reported on a one month lag | 3.00% |  |
Limited partnerships invested in private debt and equity | 86.00% | 85.00% |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 14.00% | 15.00% |
Carrying value of ten largest limited partnerships | $ 648,000,000 | $ 622,000,000 |
Carrying value of limited partnerships as percentage of aggregate partnership equity | 1.00% | 1.00% |
Income as percentage of change in partnership equity for all limited partnerships | 1.00% | 1.00% | 2.00%
Obligation to return cash | $ 0 | $ 1,000,000 |
Derivative liability, subject to master netting arrangement, collateral, right to reclaim cash offset | 0 | 0 |
Commitments to purchase or fund privately placed debt securities | 1,660,000,000 |  |
Commitments to sell various privately placed debt securities | 30,000,000 |  |
Carrying value of securities deposited under requirements of regulatory authorities | 3,100,000,000 | 3,100,000,000 |
Cash and securities deposited as collateral for letters of credit | 700,000,000 | 900,000,000 |
Fixed maturity securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
OCI, debt securities, available-for-sale, gain (loss), after adjustment, before tax | (352,000,000) | 1,431,000,000 | $ (7,850,000,000)
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | 442,000,000 | 435,000,000 |
Mortgage loans |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Financing receivable, accrued interest, after allowance for credit loss | 4,000,000 |  |
Amortized cost of mortgage loans | 48,000,000 |  |
Financing receivable, allowance for credit loss | $ 14,000,000 |  |
Non-income producing mortgage loans |  | $ 20,000,000 |
Funds Withheld Liability Securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Gross gains |  |  | 62,000,000
Debt securities, available-for-sale, realized loss |  |  | $ 44,000,000

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