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Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | $ 160 | $ 104 | $ 44 | $ 3
Equity Securities |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Equity Securities, FV-NI, Realized Gain (Loss) | 137 | 21 | 200 | 24
Less: Net gains (losses) recognized from sales of securities | 32 | 14 | 20 | 11
Unrealized Gain (Loss) on Investments | 105 | 7 | 180 | 13
Other Investments |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | 61 | 132 | 21 | 300
Less: Net gains (losses) recognized from sales of securities | 3 | 0 | 4 | 0
Unrealized Gain (Loss) on Investments | 58 | 132 | 17 | 300
Private equities |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | (28) | 49 | (17) | 80
Less: Net gains (losses) recognized from sales of securities | 0 | 0 | 0 | 0
Unrealized Gain (Loss) on Investments | (28) | 49 | (17) | 80
Equity securities, Private equities and Other investments |  |  |  |
Gain (Loss) on Securities [Line Items] |  |  |  |
Net realized gains (losses) | 170 | 202 | 204 | 404
Less: Net gains (losses) recognized from sales of securities | 35 | 14 | 24 | 11
Unrealized Gain (Loss) on Investments | $ 135 | $ 188 | $ 180 | $ 393

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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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