Net Investment and Interest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2014
Net Investment Income [Line Items]
Investment income	$ 83,443	$ 75,858	$ 68,801
Less: investment expenses	(2,724)	(1,962)	(1,629)
Investment income, related party	6,086	10,832	12,419
Net investment and interest income	86,805	84,728	79,591
Fixed Maturities [Member]
Net Investment Income [Line Items]
Investment income	63,641	58,716	53,634
Real Estate [Member]
Net Investment Income [Line Items]
Investment income	3,775	2,669	1,118
Insurance policy loans [Member]
Net Investment Income [Line Items]
Investment income	1,188	1,072	1,159
Mortgage loans [Member]
Net Investment Income [Line Items]
Investment income	14,631	10,677	9,450
Short-term, amounts held by ceding reinsurers, net and other investments [Member]
Net Investment Income [Line Items]
Investment income	$ 208	$ 2,724	$ 3,440

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.

+ References

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Amount of expenses related to the generation of investment income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.9)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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- Definition

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.2)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 16
-Article 12

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