Future Contract Benefit - Summary of Reconciliation of Future Contract Benefits (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 41,169	$ 39,864
Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,314	3,371
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	2,119	2,085	$ 1,943
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,938	3,841	$ 3,538
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,773	5,689
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	16,554	15,000
Other Operations
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	9,471	9,879
Protective | Other Operations
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,600	5,600
Swiss Re | Other Operations
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 1,900	$ 2,200