Future Contract Benefits - Summary of Reconciliation of Future Contract Benefits (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 39,864	$ 38,826
Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,371	3,251
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	2,085	2,004
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,841	3,509
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,689	5,462
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	15,000	14,818
Other Operations
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	9,879	9,782
Other Operations | Protective
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,600	5,400
Other Operations | Swiss Re
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 2,200	$ 2,300