Investments Fixed Maturities by Contractual Maturity Periods (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Schedule of Held-to-maturity Securities [Line Items]
Due In One Year or Less, Amortized Cost	$ 4,924
Due In One Year or Less, Fair Value	4,899
Due After One Year Through Five Years, Amortized Cost	5,378
Due After One Year Through Five Years, Fair Value	5,219
Due After Five Year Through Ten Years, Amortized Cost	132
Due After Five Year Through Ten Years, Fair Value	125
Due After Ten Years, Amortized Cost	1,171
Due After Ten Years, Fair Value	1,118
Fixed maturities, cost	11,605	$ 14,707
Estimated Fair Value, Fixed Maturities	$ 11,361	$ 14,541

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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