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

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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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.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section S99
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