Insurance Liabilities - Adjustments to Policyholder Contract Deposits (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021	Dec. 31, 2020
Policyholder Account Balance [Line Items]
Policyholder contract deposits	$ 162,474	$ 158,494	$ 157,858	$ 152,809	$ 148,422
Individual Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits	92,536	89,554	88,572	84,097	79,203
Group Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits	41,913	43,395	43,850	43,902	43,229
Life Insurance
Policyholder Account Balance [Line Items]
Policyholder contract deposits	10,190	10,224	10,209	10,183	10,286
Institutional Markets
Policyholder Account Balance [Line Items]
Policyholder contract deposits	14,443	11,734	11,596	10,804	11,559
Other Operations before consolidation and eliminations
Policyholder Account Balance [Line Items]
Policyholder contract deposits	$ 3,392	$ 3,587	$ 3,631	$ 3,823	4,145
Other Operations
Policyholder Account Balance [Line Items]
Policyholder contract deposits					(199)
As Previously Reported
Policyholder Account Balance [Line Items]
Policyholder contract deposits					154,669
As Previously Reported | Individual Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits					84,874
As Previously Reported | Group Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits					43,805
As Previously Reported | Life Insurance
Policyholder Account Balance [Line Items]
Policyholder contract deposits					10,286
As Previously Reported | Institutional Markets
Policyholder Account Balance [Line Items]
Policyholder contract deposits					11,559
As Previously Reported | Other Operations before consolidation and eliminations
Policyholder Account Balance [Line Items]
Policyholder contract deposits					4,145
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s)
Policyholder Account Balance [Line Items]
Policyholder contract deposits					(6,247)
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s) | Individual Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits					(5,671)
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s) | Group Retirement
Policyholder Account Balance [Line Items]
Policyholder contract deposits					(576)
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s) | Life Insurance
Policyholder Account Balance [Line Items]
Policyholder contract deposits					0
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s) | Institutional Markets
Policyholder Account Balance [Line Items]
Policyholder contract deposits					0
Adjustment for the reclassification of the embedded derivative liability to market risk benefits, net of the host adjustment(s) | Other Operations before consolidation and eliminations
Policyholder Account Balance [Line Items]
Policyholder contract deposits					$ 0