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Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) | $ (101) | $ (77)
Equity Securities |  |
Gain (Loss) on Securities [Line Items] |  |
Equity Securities, FV-NI, Realized Gain (Loss) | 3 | 11
Less: Net gains (losses) recognized from sales of securities | (3) | (5)
Unrealized Gain (Loss) on Investments | 6 | 16
Other Investments |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) | 168 | 0
Less: Net gains (losses) recognized from sales of securities | 0 |
Unrealized Gain (Loss) on Investments | 168 |
Alternative Investment |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) | 31 | 15
Less: Net gains (losses) recognized from sales of securities | 0 | 0
Unrealized Gain (Loss) on Investments | 31 | 15
Equity securities and other investments |  |
Gain (Loss) on Securities [Line Items] |  |
Net realized gains (losses) | 202 | 26
Less: Net gains (losses) recognized from sales of securities | (3) | (5)
Unrealized Gain (Loss) on Investments | $ 205 | $ 31

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- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-4 + Details
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- Definition The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 + Details
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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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-9 + Details
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