Accumulated Other Comprehensive Income (Schedule of Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income [Abstract]
Net unrealized holding gains arising during period, before tax	$ (103)	$ (1,095)	$ 216
Reclassification adjustments, before tax	(8)	(22)	(6)
Other comprehensive gain, before tax	(111)	(1,117)	210
Net unrealized holding gains arising during period, tax effect	(41)	(433)	85
Reclassification adjustments, tax effect	(3)	(7)	(2)
Other comprehensive gain, tax effect	(44)	(440)	83
Net unrealized holding gains arising during period, net of tax	(62)	(662)	131
Reclassification adjustments, net of tax	(5)	(15)	(4)
Other comprehensive gain, net of tax	$ (67)	$ (677)	$ 127