Insurance (Reconciliation of Separate Account Liability) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022
Separate Account, Liability [Line Items]
Separate account liabilities	$ 76,602	$ 78,880	$ 76,069
Variable income annuities	134		123
Pension risk transfer annuities	19		15
Rollforwards Total
Separate Account, Liability [Line Items]
Separate account liabilities	$ 76,449		$ 75,931

Amount of liability for variable contract in which all or portion of contract holder's funds is allocated to specific separate account and supported by assets held in separate account.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480078/944-80-55-18

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
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-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480109/944-80-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 80
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480141/944-80-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.7-03(a)(18))
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147480109/944-80-50-2

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant