Future Contract Benefits - Summary of Gross Premiums and Interest Accretion (UL and Other) (Details) - UL and Other - 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 assessments	$ 564	$ 787	$ 1,345	$ 1,487
Interest accretion	$ 251	$ 233	$ 499	$ 461

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