Investments Schedule of Gains and Losses on Equity and Other Investments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	$ (304)	$ (503)	$ (381)	$ (480)
Equity Securities
Gain (Loss) on Securities [Line Items]
Equity Securities, FV-NI, Realized Gain (Loss)	28	(263)	39	(207)
Less: Net gains (losses) recognized from sales of securities	2	163	(3)	418
Unrealized Gain (Loss) on Investments	26	(426)	42	(625)
Other Investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	20	4	35	59
Less: Net gains (losses) recognized from sales of securities	0	0	0	0
Unrealized Gain (Loss) on Investments	20	4	35	59
Equity securities and other investments
Gain (Loss) on Securities [Line Items]
Net realized gains (losses)	48	(259)	74	(148)
Less: Net gains (losses) recognized from sales of securities	2	163	(3)	418
Unrealized Gain (Loss) on Investments	$ 46	$ (422)	$ 77	$ (566)

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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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 4
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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))
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 2
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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