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Investments (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Gain (Loss) on Securities [Line Items] |  |  |
Non-income producing fixed maturity securities | $ 1,000,000 | $ 1,000,000 |
Investments that exceed ten percent of stockholders' equity | 0 | 0 |
Mortgage loan losses due to changes in expected credit losses | (10,000,000) | 21,000,000 | $ 0
Limited partnership investments | 1,859,000,000 | 1,619,000,000 |
Undistributed earnings of limited partnership investments | $ 266,000,000 | $ 235,000,000 |
Percentage of limited partnerships reported on a current basis | 32.00% |  |
Percentage of limited partnerships reported on a one month lag | 6.00% |  |
Percentage of limited partnerships employing hedge fund strategies focused on fixed income and equity investments | 32.00% | 51.00% |
Limited partnerships invested in private debt and equity | 68.00% | 49.00% |
Carrying value of ten largest limited partnerships | $ 665,000,000 | $ 775,000,000 |
Carrying value of limited partnerships as percentage of aggregate partnership equity | 1.00% | 2.00% |
Income as percentage of change in partnership equity for all limited partnerships | 2.00% | 2.00% | 2.00%
Obligation to return cash | $ 0 | $ 0 |
Notional value | 270,000,000 | 190,000,000 |
Derivative liability, fair value, gross liability | (12,000,000) | (19,000,000) |
Commitments to purchase or fund privately placed debt securities | 1,230,000,000 |  |
Commitments to sell various privately placed debt securities | 90,000,000 |  |
Carrying value of securities deposited under requirements of regulatory authorities | 3,000,000,000 | 3,000,000,000 |
Cash and securities deposited as collateral for letters of credit | 1,200,000,000 | 1,100,000,000 |
Non-Income Producing Mortgage Loans | 7,000,000 | 0 |
5.875% face amount of $500, due August 15, 2020 | Senior Notes |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Realized investment gains (losses) |  | (20,000,000) | $ 21,000,000
Face amount |  | 400,000,000 | 500,000,000
Common Stock |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Equity securities, FV-NI, gain (loss) | 28,000,000 | 34,000,000 |
Non-redeemable preferred stock |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Equity securities, FV-NI, gain (loss) | 2,000,000 | (3,000,000) |
Fixed maturity securities |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Debt securities, available-for-sale, accrued interest, after allowance for credit loss | 369,000,000 | 371,000,000 |
OCI, debt securities, available-for-sale, gain (loss), after adjustment, before tax | (1,272,000,000) | $ 1,637,000,000 | $ 2,620,000,000
Mortgage loans |  |  |
Gain (Loss) on Securities [Line Items] |  |  |
Financing receivable, accrued interest, after allowance for credit loss | $ 3,000,000 |  |

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