Investments Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Components of Net Investment Income [Abstract]
Taxable bonds	$ 1,761	$ 1,537
Tax exempt municipal bonds	1,085	794
Cash equivalents and short-term investments	260	87
Dividends on equity securities	412	110
Gross investment income	3,518	2,528
Investment expenses	(289)	(242)
Net investment income	$ 3,229	$ 2,286

Interest income derived from funds deposited with both domestic and foreign financial institutions including funds in money market and other accounts.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.4)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities exempt from state, federal and other income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
-Section S99
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Amount of operating interest income, including amortization and accretion of premiums and discounts, on securities subject to state, federal and other income tax.

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Amount of dividend income on nonoperating securities.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.5-03.9)
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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.

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