Net Investment and Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Net Investment Income [Line Items]
Investment income	$ 115,436	$ 111,913	$ 101,216
Less: investment expenses	(4,502)	(4,766)	(3,820)
Investment income, related party		3,326	4,880
Net investment and interest income	110,934	110,473	102,276
Fixed Maturities [Member]
Net Investment Income [Line Items]
Investment income	99,348	84,476	73,041
Real Estate [Member]
Net Investment Income [Line Items]
Investment income	5,538	5,344	5,189
Insurance policy loans [Member]
Net Investment Income [Line Items]
Investment income	1,305	1,212	1,212
Mortgage loans [Member]
Net Investment Income [Line Items]
Investment income	16,674	17,783	20,617
Short-term, amounts held by ceding reinsurers, net and other investments [Member]
Net Investment Income [Line Items]
Investment income	$ (7,429)	$ 3,098	$ 1,157

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)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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
-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 http://asc.fasb.org/extlink&oid=114873790&loc=SL114874131-224263

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