Market Risk Benefits - Balances and changes in market risk benefits (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
Market Risk Benefit [Line Items]
Market risk benefit in an asset position					$ 176
Reinsured market risk benefit					162
Market risk benefit assets, at fair value	$ 912	$ 796		$ 338	338
Market risk benefit liabilities, at fair value	5,705	4,736		8,739	8,739
Net	4,793	3,940	$ 6,889		8,401
As Previously Reported
Market Risk Benefit [Line Items]
Market risk benefit assets, at fair value		0		0
Market risk benefit liabilities, at fair value		0		$ 0
Net					0
Adjustment for the reclassification of the embedded derivative liability from policyholder contract deposits, net of the host adjustment
Market Risk Benefit [Line Items]
Net					6,247
Adjustment for the reclassification of additional liabilities from Future policy benefits
Market Risk Benefit [Line Items]
Net					1,609
Adjustments for the cumulative effect of the changes to our own credit risk between the original contract issuance date and the transition date
Market Risk Benefit [Line Items]
Net					2,327
Adjustment for the removal of related balances in Accumulated other comprehensive income (loss) originating from unrealized gains (losses)
Market Risk Benefit [Line Items]
Net					(605)
Adjustment for the remaining difference (exclusive of our own credit risk change and host contract adjustments) between previous carrying amount and fair value measurement for the MRB
Market Risk Benefit [Line Items]
Net					(1,177)
Individual Retirement
Market Risk Benefit [Line Items]
Market risk benefit in an asset position					176
Reinsured market risk benefit					162
Market risk benefit assets, at fair value					338
Market risk benefit liabilities, at fair value					7,937
Net	4,485	3,644	6,307		7,599
Individual Retirement | As Previously Reported
Market Risk Benefit [Line Items]
Net					0
Individual Retirement | Adjustment for the reclassification of the embedded derivative liability from policyholder contract deposits, net of the host adjustment
Market Risk Benefit [Line Items]
Net					5,671
Individual Retirement | Adjustment for the reclassification of additional liabilities from Future policy benefits
Market Risk Benefit [Line Items]
Net					1,388
Individual Retirement | Adjustments for the cumulative effect of the changes to our own credit risk between the original contract issuance date and the transition date
Market Risk Benefit [Line Items]
Net					2,140
Individual Retirement | Adjustment for the removal of related balances in Accumulated other comprehensive income (loss) originating from unrealized gains (losses)
Market Risk Benefit [Line Items]
Net					(516)
Individual Retirement | Adjustment for the remaining difference (exclusive of our own credit risk change and host contract adjustments) between previous carrying amount and fair value measurement for the MRB
Market Risk Benefit [Line Items]
Net					(1,084)
Group Retirement
Market Risk Benefit [Line Items]
Market risk benefit in an asset position					0
Reinsured market risk benefit					0
Market risk benefit assets, at fair value					0
Market risk benefit liabilities, at fair value					802
Net	$ 308	$ 296	$ 582		802
Group Retirement | As Previously Reported
Market Risk Benefit [Line Items]
Net					0
Group Retirement | Adjustment for the reclassification of the embedded derivative liability from policyholder contract deposits, net of the host adjustment
Market Risk Benefit [Line Items]
Net					576
Group Retirement | Adjustment for the reclassification of additional liabilities from Future policy benefits
Market Risk Benefit [Line Items]
Net					221
Group Retirement | Adjustments for the cumulative effect of the changes to our own credit risk between the original contract issuance date and the transition date
Market Risk Benefit [Line Items]
Net					187
Group Retirement | Adjustment for the removal of related balances in Accumulated other comprehensive income (loss) originating from unrealized gains (losses)
Market Risk Benefit [Line Items]
Net					(89)
Group Retirement | Adjustment for the remaining difference (exclusive of our own credit risk change and host contract adjustments) between previous carrying amount and fair value measurement for the MRB
Market Risk Benefit [Line Items]
Net					$ (93)