Future Contract Benefit - Summary of Weighted-Average Interest Rates (Details)	Mar. 31, 2025	Mar. 31, 2024
Payout Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	4.00%	3.90%
Current discount rate	5.20%	5.20%
Traditional Life
Liability for Future Policy Benefit, Activity [Line Items]
Interest accretion rate	5.00%	5.00%
Current discount rate	4.90%	5.00%

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