Future Contract Benefits - Summary of Weighted-Average Interest Rates (UL and Other) (Details)	Mar. 31, 2026	Mar. 31, 2025
UL and Other
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	5.40%	5.40%

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