Investments, Aggregated by Industry (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Investments aggregated by industry [Abstract]
Carrying value	$ 208,041	$ 210,670
Cost or amortized cost	207,660	210,505
Carrying value	244,441	244,177
Cost or amortized cost	232,112	235,208
Unrealized gains (losses)	12,329	8,969
U.S. Treasury Securities and Obligations of U.S. Government Agencies and Authorities [Member]
Investments aggregated by industry [Abstract]
Carrying value	29,469	31,102
Cost or amortized cost	29,788	31,458
Unrealized gains (losses)	(319)	(356)
Obligations of States and Political Subdivisions [Member]
Investments aggregated by industry [Abstract]
Carrying value	17,690	17,572
Cost or amortized cost	17,250	17,255
Unrealized gains (losses)	440	317
Utilities and Telecom [Member]
Investments aggregated by industry [Abstract]
Carrying value	19,527	19,635
Cost or amortized cost	17,622	17,624
Unrealized gains (losses)	1,905	2,011
Financial Services [Member]
Investments aggregated by industry [Abstract]
Carrying value	58,068	62,684
Cost or amortized cost	55,976	61,141
Unrealized gains (losses)	2,092	1,543
Other Business - Diversified [Member]
Investments aggregated by industry [Abstract]
Carrying value	48,570	57,663
Cost or amortized cost	49,635	58,732
Unrealized gains (losses)	(1,065)	(1,069)
Other Consumer - Diversified [Member]
Investments aggregated by industry [Abstract]
Carrying value	58,118	42,271
Cost or amortized cost	48,842	35,748
Unrealized gains (losses)	9,276	6,523
Other Investment [Member]
Investments aggregated by industry [Abstract]
Carrying value	12,999	13,250
Cost or amortized cost	$ 12,999	$ 13,250