| **Condensed Consolidated Balance Sheets (Unaudited) - (Parenthetical) - USD ($) $ in Millions**                                                                                                                                                                                                                                                                     | Sep. 30, 2023 | Dec. 31, 2022 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Fixed maturities securities at amortized cost                                                                                                                                                                                                                                                                                                                       | $ 42,366      | $ 41,032      |  |
| Marketable securities fixed maturities allowance for credit loss                                                                                                                                                                                                                                                                                                    | 18            | 1             |  |
| Equity securities at cost                                                                                                                                                                                                                                                                                                                                           | 712           | 703           |  |
| Mortgage loans on real estate commercial and consumer allowance for credit loss                                                                                                                                                                                                                                                                                     | 35            | 24            |  |
| Allowance for uncollectible reinsurance                                                                                                                                                                                                                                                                                                                             | 22            | 22            |  |
| Allowance for uncollectible insurance receivables                                                                                                                                                                                                                                                                                                                   | 29            | 29            |  |
| Accumulated depreciation on property and equipment                                                                                                                                                                                                                                                                                                                  | 287           | 280           |  |
| Other Assets                                                                                                                                                                                                                                                                                                                                                        | 2,474         | 2,274         | [1] |
| Other Liabilities                                                                                                                                                                                                                                                                                                                                                   | $ 3,101       | $ 2,983       | [1] |
| Common stock, par value (in usd per share)                                                                                                                                                                                                                                                                                                                          | $ 2.50        | $ 2.50        |  |
| Common stock, shares authorized (in shares)                                                                                                                                                                                                                                                                                                                         | 500,000,000   | 500,000,000   |  |
| Common stock, shares issued (in shares)                                                                                                                                                                                                                                                                                                                             | 273,040,243   | 273,040,243   |  |
| Common stock, shares outstanding (in shares)                                                                                                                                                                                                                                                                                                                        | 270,865,467   | 270,895,902   |  |
| Treasury stock, shares (in shares)                                                                                                                                                                                                                                                                                                                                  | 2,174,776     | 2,144,341     |  |
| Related Party                                                                                                                                                                                                                                                                                                                                                       |          |          |  |
| Other Assets                                                                                                                                                                                                                                                                                                                                                        | $ 20          | $ 18          |  |
| Other Liabilities                                                                                                                                                                                                                                                                                                                                                   | $ 20          | $ 26          |  |
|                                                                                                                                                                                                                                                                                                                                                                     |
| [1]As of January 1, 2023, the Company adopted ASU 2018-12 using the modified retrospective method applied as of the transition date of January 1, 2021.  Prior period amounts in the financial statements have been adjusted to reflect application of the new guidance.  See Note A to the Condensed Consolidated Financial Statements for additional information. |

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.
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Face amount or stated value per share of common stock.
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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.
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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.
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Amount of assets classified as other.
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Amount of liabilities classified as other.
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The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value.
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Amount of allowance for credit loss on reinsurance recoverable.
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Number of previously issued common shares repurchased by the issuing entity and held in treasury.
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