Investments, Roll-forward of Financial Instruments Measured at Fair Value (Details) - Fixed Maturities [Member] - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Mar. 31, 2017
Assets measured at fair value on a recurring basis [Abstract]
Balance, beginning of period	$ 1,339	$ 1,369	$ 1,302	$ 1,264
Total unrealized gains (losses) included in other comprehensive income (loss)	7	(30)	30	38
Balance, end of period	$ 1,346	$ 1,339	$ 1,332	$ 1,302

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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