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Investments (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Gain (Loss) on Securities [Line Items] |  |  |
Non-income producing fixed maturity securities | $ 0 | $ 1,000,000 |
Non-Income Producing Mortgage Loans | 7,000,000 | 7,000,000 |
Investments that exceed ten percent of stockholders' equity | 0 | 0 |
Investment and derivative, realized gain (loss), coinsurance agreement | 18,000,000 |  |
Gross gains | 120,000,000 | 186,000,000 | $ 220,000,000
Debt securities, available-for-sale, realized loss | 261,000,000 | 90,000,000 | 220,000,000
Realized investment gains (losses) |  |  | 20,000,000
Mortgage loan losses due to changes in expected credit losses | 8,000,000 | (10,000,000) | $ 21,000,000
Limited partnership investments | 1,926,000,000 | 1,859,000,000 |
Undistributed earnings of limited partnership investments | $ 176,000,000 | $ 266,000,000 |
Percentage of limited partnerships reported on a current basis | 26.00% |  |
Percentage of limited partnerships reported on a one month lag | 5.00% |  |
Limited partnerships invested in private debt and equity | 76.00% | 68.00% |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 24.00% | 32.00% |
Carrying value of ten largest limited partnerships | $ 633,000,000 | $ 665,000,000 |
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 | 2.00% | 2.00% | 2.00%
Obligation to return cash | $ 1,000,000 | $ 0 |
Derivative liability, subject to master netting arrangement, collateral, right to reclaim cash offset | 0 | 0 |
Notional value |  | 270,000,000 |
Other liabilities | (1,000,000) | (12,000,000) |
Increase (decrease) fixed maturity securities | 224,000,000 |  |
Increase (decrease) short term investments | 4,000,000 |  |
Increase (decrease) accrued investment income | 2,000,000 |  |
Increase (decrease) funds withheld liability | 216,000,000 |  |
Embedded derivative, fair value of embedded derivative liability | 14,000,000 |  |
Commitments to purchase or fund privately placed debt securities | 1,455,000,000 |  |
Commitments to sell various privately placed debt securities | 60,000,000 |  |
Carrying value of securities deposited under requirements of regulatory authorities | 2,800,000,000 | 3,000,000,000 |
Cash and securities deposited as collateral for letters of credit | 900,000,000 | 1,200,000,000 |
5.875% face amount of $500, due August 15, 2020 | Senior Notes |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Face amount |  |  | $ 400,000,000
Fixed maturity securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
OCI, debt securities, available-for-sale, gain (loss), after adjustment, before tax | (7,850,000,000) | (1,272,000,000) | $ 1,637,000,000
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | 394,000,000 | $ 369,000,000 |
Mortgage loans |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Financing receivable, accrued interest, after allowance for credit loss | 4,000,000 |  |
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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