Investments - Narrative, Cost or Amortized Cost, Gross Unrealized Gains and Losses, Fair Value and OTTI (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Investments
Fair Value	$ 45,549
Cost or Amortized Cost	41,783
States, municipalities and political subdivisions \| Pre-refunded bonds
Investments
Fair Value	3,699	$ 13,820
Credit concentration \| Corporate fixed maturity and equity securities \| Europe
Investments
Cost or Amortized Cost	3,141	4,852
Gross Unrealized Gains	$ 298	$ 501
Investment portfolio \| Credit concentration \| Corporate fixed maturity and equity securities \| Europe
Investments
Concentration percentage	13.00%	6.00%
Investment portfolio \| Credit concentration \| Corporate fixed maturity and equity securities \| Europe \| Finance Sector
Investments
Concentration percentage	2.00%
Investment portfolio \| Credit concentration \| States, municipalities and political subdivisions \| Individual U. S. states \| Maximum
Investments
Concentration percentage	5.00%	4.00%
Investment portfolio \| Credit concentration \| States, municipalities and political subdivisions \| Municipal revenue bonds
Investments
Concentration percentage	48.00%	55.00%

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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