Future Contract Benefits - 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	$ 41,409	$ 40,174
Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,290	3,343
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	2,118	2,084	$ 1,943
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,660	3,553	$ 3,252
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	17,214	15,752
Other Operations
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	9,354	9,753
Other Operations | Protective
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,600	5,600
Other Operations | Swiss Re
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 1,800	$ 2,100