Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
Sep. 30, 2025 |
|---|---|---|---|
| Statement of Financial Position [Abstract] | |||
| Fixed maturities, amortized cost | $ 95,719 | $ 82,704 | $ 88,247 |
| Short-term investments, amortized cost | 2,125 | 10,005 | 1,515 |
| Nonredeemable preferred stocks, cost | 212 | 419 | 454 |
| Common equities, cost | 909 | 819 | 808 |
| Premium receivable, allowance for credit loss | 588 | 552 | 516 |
| Property and equipment, accumulated depreciation | $ 1,428 | $ 1,460 | $ 1,398 |
| Common shares, par value (USD per share) | $ 1.00 | $ 1.00 | $ 1.00 |
| Common shares, authorized (shares) | 900,000,000 | 900,000,000 | 900,000,000 |
| Common shares, issued (shares) | 798,000,000 | 798,000,000 | 798,000,000 |
| Treasury shares (shares) | 219,000,000 | 212,000,000 | 212,000,000 |
| X | ||||||||||
- Definition Amortized cost of investments in long-term debt securities (fixed maturities) measured at fair value with changes in fair value recognized in other comprehensive income (available-for-sale). No definition available.
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- Definition This item represents the cost of Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. No definition available.
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- Definition Equity Securities Common Equities Cost No definition available.
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- Definition Equity Securities Nonredeemable Preferred Stock Cost No definition available.
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- Definition Amount of accumulated depreciation, depletion, and amortization of property, plant, and equipment. Includes, but is not limited to, land and land improvement; building; machinery and equipment; furniture and fixture; and work of art, historical treasure, or similar asset classified as collection. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Number of previously issued common shares repurchased by the issuing entity and held in treasury. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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