Life Insurance Liabilities (Sensitive Life Insurance Type Products) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2024	Dec. 31, 2023
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Interest expense	$ 76,581,000	$ 67,450,000	$ 215,297,000	$ 191,991,000
Life Insurance Segment [Member] | Oxford
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Gross premiums	$ 37,561,000	$ 39,979,000	37,561,000	39,979,000
Interest expense			$ 11,402,000	$ 11,463,000
Expected future lifetime (persistency) of policies in force (years)	6 years 9 months 18 days	6 years 10 months 24 days	6 years 9 months 18 days	6 years 10 months 24 days
Weighted average original interest rate of the liability for future policy benefits	4.97%	5.00%	4.97%	5.00%
Weighted average current interest rate of the liability for future policy benefits	5.20%	4.80%	5.20%	4.80%
Life Insurance Segment [Member] | Oxford | Expected gross premiums:
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Undiscounted balance	$ 348,354,000	$ 377,068,000	$ 348,354,000	$ 377,068,000
Discounted balance at original discount rate	270,029,000	291,900,000	270,029,000	291,900,000
Discounted balance at current discount rate	274,428,000	281,927,000	274,428,000	281,927,000
Life Insurance Segment [Member] | Oxford | Expected policy benefits:
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Undiscounted balance	714,265,000	752,194,000	714,265,000	752,194,000
Discounted balance at original discount rate	496,385,000	519,099,000	496,385,000	519,099,000
Discounted balance at current discount rate	$ 510,163,000	$ 499,702,000	$ 510,163,000	$ 499,702,000
Life Insurance Segment [Member] | Oxford | Lapses actual experience
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Market Risk Benefit Measurement Input	0.0489	0.0457	0.0489	0.0457
Life Insurance Segment [Member] | Oxford | Mortality expected experience
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Market Risk Benefit Measurement Input	0.0543	0.0507	0.0543	0.0507
Life Insurance Segment [Member] | Oxford | Lapses actual experience
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Market Risk Benefit Measurement Input	0.0218	0.0218	0.0218	0.0218
Life Insurance Segment [Member] | Oxford | Lapses expected experience
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Market Risk Benefit Measurement Input	0.0272	0.0264	0.0272	0.0264