Net Investment and Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Net Investment Income [Line Items]
Investment income	$ 129,970	$ 142,683	$ 115,436
Less: investment expenses	(7,032)	(4,854)	(4,502)
Investment income, related party	0	0	0
Net investment and interest income	122,938	137,829	110,934
Fixed Maturities [Member]
Net Investment Income [Line Items]
Investment income	102,021	107,434	99,348
Real Estate [Member]
Net Investment Income [Line Items]
Investment income	5,769	7,304	5,538
Insurance policy loans [Member]
Net Investment Income [Line Items]
Investment income	829	974	1,305
Mortgage loans [Member]
Net Investment Income [Line Items]
Investment income	18,248	17,164	16,674
Short-term, amounts held by ceding reinsurers, net and other investments [Member]
Net Investment Income [Line Items]
Investment income	$ 3,103	$ 9,807	$ (7,429)

Income derived from investments in related party.

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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
-Subparagraph (SX 210.5-03.9)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 944
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-Section S99
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-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 http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

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