Reinsurance (Life Insurance In Force) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Reinsurance Disclosures [Abstract]
Direct gross life insurance face amount in force	$ 893,787,108	$ 840,190,324
Assumed gross life insurance face amount in force	41,584,568	42,499,716
Reinsurance ceded	(864,942,222)	(817,213,475)
Net life insurance face amount in force	$ 70,429,454	$ 65,476,565

Amount of life insurance issued and outstanding assumed from other entities. Includes, but not limited to, dividends and adjustments to face value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 2
-Subparagraph (SX 210.12-17)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574992-122915

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- Definition

Amount of life insurance issued and outstanding ceded to other entities. Includes, but not limited to, dividends and adjustments to face value.

+ References

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- Definition

Amount before contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

+ References

+ Details

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- Definition

Amount after contracts ceded to other entities and contracts assumed by the entity of life insurance issued and outstanding. Includes, but not limited to, dividends and adjustments to face value.

+ References

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- References

No definition available.

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