Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	$ (384)	$ (21)	$ (787)	$ 833
Equity Securities
Gain (Loss) on Securities [Line Items]
Equity Securities, FV-NI, Realized Gain (Loss)	(80)	(42)	(287)	475
Less: Net gains (losses) recognized from sales of securities	(12)	19	406	109
Unrealized Gain (Loss) on Investments	(68)	(61)	(693)	366
Other Investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	(42)	11	17	111
Less: Net gains (losses) recognized from sales of securities	0	0	0	0
Unrealized Gain (Loss) on Investments	(42)	11	17	111
Equity securities and other investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	(122)	(31)	(270)	586
Less: Net gains (losses) recognized from sales of securities	(12)	19	406	109
Unrealized Gain (Loss) on Investments	$ (110)	$ (50)	$ (676)	$ 477

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/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
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-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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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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-SubTopic 10
-Section 45
-Paragraph 28
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Amount of unrealized gain (loss) on investment.

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