Market Risk Benefits - Schedule of market risk benefits (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Market Risk Benefit [Line Items]
Asset	$ 912	$ 796
Liability	5,705	4,736
Net	4,793	3,940	$ 6,889	$ 8,401
Individual Retirement
Market Risk Benefit [Line Items]
Asset	740	661
Liability	5,225	4,305
Net	4,485	3,644	6,307	7,599
Group Retirement
Market Risk Benefit [Line Items]
Asset	172	135
Liability	480	431
Net	$ 308	$ 296	$ 582	$ 802