Future Contract Benefits - Summary of Gross Premiums and Interest Accretion (Group Protection) (Details) - Group Protection - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
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