Investments, Net Investment Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest [Abstract]
Taxable bonds	$ 9,474	$ 6,233	$ 6,031
Municipal bonds (tax exempt)	4,298	3,619	1,808
Cash equivalents and short-term investments	1,017	678	93
Dividends on equity securities	2,014	1,041	442
Gross investment income	16,803	11,571	8,374
Investment expenses	(1,115)	(1,002)	(887)
Net investment income	$ 15,688	$ 10,569	$ 7,487

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 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 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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