Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	$ (103)	$ (456)	$ (484)	$ (936)
Equity Securities
Gain (Loss) on Securities [Line Items]
Equity Securities, FV-NI, Realized Gain (Loss)	(100)	(80)	(61)	(287)
Less: Net gains (losses) recognized from sales of securities	(45)	(12)	(48)	406
Unrealized Gain (Loss) on Investments	(55)	(68)	(13)	(693)
Other Investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	(1)		(1)
Less: Net gains (losses) recognized from sales of securities	0		0
Unrealized Gain (Loss) on Investments	(1)		(1)
Equity securities and other investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)		(122)		(270)
Less: Net gains (losses) recognized from sales of securities		(12)		406
Unrealized Gain (Loss) on Investments		(110)		(676)
Fixed maturities trading, equity securities and other investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	(61)		13
Less: Net gains (losses) recognized from sales of securities	(45)		(48)
Unrealized Gain (Loss) on Investments	(16)		61
Alternative Investment
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	40	(42)	75	17
Less: Net gains (losses) recognized from sales of securities	0	0	0	0
Unrealized Gain (Loss) on Investments	$ 40	$ (42)	$ 75	$ 17

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
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
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-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
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-Paragraph 4
-Publisher FASB
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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://fasb.org/us-gaap/role/ref/legacyRef
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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
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-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
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-Name Accounting Standards Codification
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