Policy Liabilities - Additional Information (Details) - USD ($) $ in Billions	Mar. 31, 2026	Mar. 31, 2025
Life
Liability for Future Policy Benefit, Activity [Line Items]
Difference between expected future gross premiums and expected future net premiums	$ 17.7	$ 17.1
Health
Liability for Future Policy Benefit, Activity [Line Items]
Difference between expected future gross premiums and expected future net premiums	$ 6.7	$ 5.8

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