Future Contract Benefits - Summary of Gross Premiums and Interest Accretion (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	$ 34	$ 25	$ 51	$ 48
Interest accretion	22	22	44	44
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	375	312	678	626
Interest accretion	36	38	72	75
Group Protection
Liability for Future Policy Benefit, Activity [Line Items]
Gross premiums	909	926	1,823	1,859
Interest accretion	$ 53	$ 50	$ 108	$ 100

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details