Investments (Details) - Investment Information, Equity Securities - USD ($) $ in Millions |
6 Months Ended | 12 Months Ended | |
|---|---|---|---|
Jun. 30, 2024 |
Jun. 30, 2023 |
Dec. 31, 2023 |
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| Investment disclosure details | |||
| Equity securities, cost | $ 539 | $ 553 | |
| Gross gains | 119 | 96 | |
| Gross losses | 14 | 41 | |
| Equity securities, at fair value | 644 | 608 | |
| Net recognized gains on equity securities still held | 51 | $ 3 | |
| Common stock [Member] | |||
| Investment disclosure details | |||
| Equity securities, cost | 493 | 508 | |
| Gross gains | 115 | 93 | |
| Gross losses | 14 | 41 | |
| Equity securities, at fair value | 594 | 560 | |
| Non-redeemable preferred stock [Member] | |||
| Investment disclosure details | |||
| Equity securities, cost | 46 | 45 | |
| Gross gains | 4 | 3 | |
| Gross losses | 0 | 0 | |
| Equity securities, at fair value | $ 50 | $ 48 | |
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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 Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). 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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