Investments (Equity Securities) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Unrealized Gains (Losses)	$ 2,018	$ 1,589
Equity securities	750	757
Common Stock
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	411	424
Equity Securities, FV-NI, Unrealized Gains (Losses)	266	239
Equity securities	677	663
Non-redeemable preferred Stock
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	73	90
Equity Securities, FV-NI, Unrealized Gains (Losses)	0	4
Equity securities	73	94
Equity Securities
Debt and Equity Securities, FV-NI [Line Items]
Equity Securities, FV-NI, Cost	484	514
Equity Securities, FV-NI, Unrealized Gains (Losses)	266	243
Equity securities	$ 750	$ 757

Equity and Trading Securities, FV-NI, Unrealized Gains (Losses)

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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