Investments - Equity securities reported at fair value (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Debt and Equity Securities, FV-NI [Line Items] | ||
| Equity securities, at fair value | $ 779 | $ 785 |
| Common stocks | ||
| Debt and Equity Securities, FV-NI [Line Items] | ||
| Actual Cost | 334 | 332 |
| Equity securities, at fair value | 371 | 365 |
| Fair Value Over Cost | 37 | 33 |
| Perpetual preferred stocks | ||
| Debt and Equity Securities, FV-NI [Line Items] | ||
| Actual Cost | 390 | 398 |
| Equity securities, at fair value | 408 | 420 |
| Fair Value Over Cost | 18 | 22 |
| Equity securities | ||
| Debt and Equity Securities, FV-NI [Line Items] | ||
| Actual Cost | 724 | 730 |
| Equity securities, at fair value | 779 | 785 |
| Fair Value Over Cost | $ 55 | $ 55 |
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) in excess of the 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. No definition available.
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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