Future Contract Benefits - Summary of Weighted-Average Interest Rates (Details)	Dec. 31, 2023	Dec. 31, 2022
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	3.90%	3.90%
Current discount rate	4.90%	5.30%
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	5.00%	5.10%
Current discount rate	4.60%	5.10%
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	3.00%	2.80%
Current discount rate	4.70%	5.10%
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	5.30%	5.00%