Life Insurance Liabilities (Balance Changes Liabilities Investment Contracts) (Details) - Life And Annuity Insurance Product Line [Member] - USD ($) $ in Thousands	6 Months Ended
Sep. 30, 2025	Sep. 30, 2024
Policyholder Account Balance [Roll Forward]
Policyholder contract deposits account balance Beginning of year	$ 2,511,422	$ 2,411,352
Deposits received	181,834	226,771
Surrenders and withdrawals	(205,014)	(164,919)
Benefit payments	(17,448)	(19,625)
Interest credited	47,809	37,584
Other		5,868
End of period	$ 2,518,603	$ 2,497,031
Weighted average credited rate	3.80%	3.29%
Cash surrender value	$ 2,210,645	$ 2,172,013

Amount of cash to be paid to policyholder upon termination and surrender of long-duration contract issued by insurance entity.

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Amount of interest expense for allocation to policyholder account balance.

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Amount of cash inflow to policyholder account balance from premium received.

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Weighted-average crediting rate for liability for policyholder account balance, calculated at a point in time.

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Amount due to policyholder. Includes, but is not limited to, unpaid policy dividend, retrospective refund, and undistributed earnings on participating business. Excludes future policy benefit and claim expense.

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