Accumulated Other Comprehensive Income (Reclassification out of Accumulated Other Comprehensive Income (Loss) Alternate) (Details) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Related income tax expense													$ (6,793)	$ (4,386)	$ (4,578)
Net Income	$ 1,460	$ 3,751	$ 3,898	$ 3,206	$ 3,237	$ 3,482	$ 4,157	$ 2,365	$ 3,338	$ 3,225	$ 3,218	$ 2,481	12,315	13,241	12,262
Reclassification out of AOCI [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Other Income													708	1,023	436
Related income tax expense													(241)	(348)	(148)
Net Income													$ 467	$ 675	$ 288