Net Investment and Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2021
Net Investment Income [Line Items]
Investment income	$ 185,014	$ 155,541	$ 129,970
Less: investment expenses	(8,335)	(7,280)	(7,032)
Net investment and interest income	176,679	148,261	122,938
Fixed Maturities [Member]
Net Investment Income [Line Items]
Investment income	171,814	111,625	102,021
Real Estate [Member]
Net Investment Income [Line Items]
Investment income	5,734	5,648	5,769
Insurance policy loans [Member]
Net Investment Income [Line Items]
Investment income	869	705	829
Mortgage loans [Member]
Net Investment Income [Line Items]
Investment income	23,854	25,850	18,248
Short-term, amounts held by ceding reinsurers, net and other investments [Member]
Net Investment Income [Line Items]
Investment income	$ (17,257)	$ 11,713	$ 3,103

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
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Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(2))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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+ References

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