Securities Available for Sale (Schedule of Securities in an Unrealized Loss Position) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value
Less than 12 months	$ 132,630	$ 103,549
More than 12 months	146,331	165,811
Total	278,961	269,360
Gross Unrealized Losses
Less than 12 months	(2,732)	(841)
More than 12 months	(5,977)	(4,358)
Total	(8,709)	(5,199)
U.S. Government Agencies [Member]
Fair Value
Less than 12 months	9,768	9,941
More than 12 months	23,931	24,411
Total	33,699	34,352
Gross Unrealized Losses
Less than 12 months	(232)	(59)
More than 12 months	(1,158)	(690)
Total	(1,390)	(749)
U.S. Agency Mortgage-Backed Securities [Member]
Fair Value
Less than 12 months	13,266	10,326
More than 12 months	32,837	37,123
Total	46,103	47,449
Gross Unrealized Losses
Less than 12 months	(372)	(78)
More than 12 months	(1,564)	(838)
Total	(1,936)	(916)
U.S. Agency Collateralized Mortgage Obligations [Member]
Fair Value
Less than 12 months	28,434	29,551
More than 12 months	19,773	20,980
Total	48,207	50,531
Gross Unrealized Losses
Less than 12 months	(783)	(280)
More than 12 months	(1,085)	(618)
Total	(1,868)	(898)
Asset-backed Securities [Member]
Fair Value
Less than 12 months	7,736
More than 12 months
Total	7,736
Gross Unrealized Losses
Less than 12 months	(32)
More than 12 months
Total	(32)
Corporate Bonds [Member]
Fair Value
Less than 12 months	41,687	38,543
More than 12 months	16,641	15,019
Total	58,328	53,562
Gross Unrealized Losses
Less than 12 months	(893)	(282)
More than 12 months	(689)	(307)
Total	(1,582)	(589)
Obligations of States and Political Subdivisions [Member]
Fair Value
Less than 12 months	31,739	15,188
More than 12 months	53,149	68,278
Total	84,888	83,466
Gross Unrealized Losses
Less than 12 months	(420)	(142)
More than 12 months	(1,481)	(1,905)
Total	$ (1,901)	$ (2,047)