Income Taxes (Schedule of Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Asset
Net operating loss and tax credit carryforward	$ 20,977	$ 22,282
Allowance for loan losses	8,094	7,416
Pension and other benefits	5,141	4,488
Net unrealized losses on AFS securities	3,227	2,047
Net unrealized losses on derivative instruments	3,066	3,432
Purchase accounting and deposit premium	1,430	2,856
Deferred compensation and benefits	1,791	2,129
Net unrealized losses on postretirement plans	1,147	1,102
Other	956	77
Total	45,829	45,829
Liability
Depreciation	(4,520)	(4,298)
Deferred loan origination fees	(2,046)	(1,815)
Total	(6,566)	(6,113)
Income Tax Contingency [Line Items]
Deferred Tax Assets, Net of Valuation Allowance	$ 39,263	$ 39,716
Minimum [Member]
Income Tax Contingency [Line Items]
Open tax years	2013
Maximum [Member]
Income Tax Contingency [Line Items]
Open tax years	2015