Future Contract Benefits - Summary of Gross Premiums and Interest Accretion (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	$ 116	$ 133	$ 95
Interest accretion	86	84	84
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	1,252	1,211	1,103
Interest accretion	143	134	134
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	3,549	3,393	3,145
Interest accretion	159	141	145
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	3,219	2,818	3,150
Interest accretion	$ 775	$ 626	$ 498