Future Contract Benefits - Summary of Reconciliation of Future Contract Benefits (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 41,957	$ 42,360
Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,194	3,294
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	1,990	2,036	$ 2,032
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	3,479	3,521	$ 3,566
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,793	5,836
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	18,606	18,597
Other Operations [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	8,895	9,076
Other Operations [Member] | Protective
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	5,300	5,400
Other Operations [Member] | Swiss Re
Liability for Future Policy Benefit, Activity [Line Items]
Future contract benefits	$ 1,900	$ 1,900