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Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2024 | Sep. 30, 2023 | Sep. 30, 2024 | Sep. 30, 2023
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | $ 198 | $ (103) | $ 201 | $ (484)
Equity Securities |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Equity Securities, FV-NI, Realized Gain (Loss) | 123 | (100) | 147 | (61)
Less: Net gains (losses) recognized from sales of securities | (6) | (45) | 5 | (48)
Unrealized Gain (Loss) on Investments | 129 | (55) | 142 | (13)
Other Investments |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | 152 | (1) | 452 | (1)
Less: Net gains (losses) recognized from sales of securities | 2 | 0 | 2 | 0
Unrealized Gain (Loss) on Investments | 150 | (1) | 450 | (1)
Private Equities |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | (41) | 40 | 39 | 75
Less: Net gains (losses) recognized from sales of securities | 0 | 0 | 0 | 0
Unrealized Gain (Loss) on Investments | (41) | 40 | 39 | 75
Equity securities and other investments |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | 234 | (61) | 638 | 13
Less: Net gains (losses) recognized from sales of securities | (4) | (45) | 7 | (48)
Unrealized Gain (Loss) on Investments | $ 238 | $ (16) | $ 631 | $ 61

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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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