Securities (Schedule of Securities with Unrealized Losses) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months Fair Value	$ 94,322	$ 205,584
Less than 12 Months Unrealized Loss	(887)	(2,285)
12 Months or More Fair Value	405,289	274,681
12 Months or More Unrealized Loss	(13,192)	(7,865)
Total Fair Value	499,611	480,265
Total Unrealized Loss	(14,079)	(10,150)
Obligations of State and Political Subdivisions
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months Fair Value	37,936	33,230
Less than 12 Months Unrealized Loss	(286)	(237)
12 Months or More Fair Value	49,071	24,161
12 Months or More Unrealized Loss	(1,037)	(624)
Total Fair Value	87,007	57,391
Total Unrealized Loss	(1,323)	(861)
MBS/CMO – Residential
Debt Securities, Available-for-sale [Line Items]
Less than 12 Months Fair Value	56,386	172,354
Less than 12 Months Unrealized Loss	(601)	(2,048)
12 Months or More Fair Value	356,218	250,520
12 Months or More Unrealized Loss	(12,155)	(7,241)
Total Fair Value	412,604	422,874
Total Unrealized Loss	$ (12,756)	$ (9,289)