Investments Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Components of Net Investment Income [Abstract]
Taxable bonds	$ 2,548	$ 1,539	$ 6,548	$ 4,584
Tax exempt municipal bonds	1,068	990	3,236	2,602
Cash equivalents and short-term investments	327	206	804	460
Dividends on equity securities	445	287	1,369	582
Gross investment income	4,388	3,022	11,957	8,228
Investment expenses	(303)	(257)	(861)	(745)
Net investment income	$ 4,085	$ 2,765	$ 11,096	$ 7,483

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

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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.

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Amount of expenses related to the generation of investment income.

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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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