Shareholders' Equity (AOCI tax effect) (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Other Comprehensive Income, Before Tax:
Net Unrealized Gains (Losses) Arising During the Period	$ (5,263)	$ (18,647)	$ (5,448)
(Gain) Loss on Sale, before Tax			(190)
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	1,982	1,605	2,136
Net Unrealized Gains (Losses) on Investment Securities	(3,281)	(17,042)	(3,502)
Net Actuarial Gains (Losses) Arising During the Period	884	(954)	7,335
Amortization of Net Actuarial Losses (Gains)	1,382	1,224	1,624
Amortization of Prior Service Credit, before tax	(322)	(322)	(322)
Defined Benefit Plans, Net	1,944	(52)	8,637
Other Comprehensive Income (Loss)	(1,337)	(17,094)	5,135
Other Comprehensive Income, Tax Effect:
Net Unrealized Gains Arising During the Period	(2,078)	(7,358)	(2,138)
(Gain) Loss on Sale, Tax			(75)
Amortization of Unrealized Holding (Gains) Losses on HTM Securities	783	634	836
Net Unrealized Gains (Losses) on Investment Securities	(1,295)	(6,724)	(1,377)
Net Actuarial Gains (Losses) Arising During the Period	349	(377)	2,869
Amortization of Net Actuarial Losses (Gains)	545	483	641
Amortization of Prior Service Credit	(127)	(127)	(127)
Defined Benefit Plans, Net	767	(21)	3,383
Other Comprehensive Income (Loss)	(528)	(6,745)	2,006
Other Comprehensive Income, Net of Tax:
Net Unrealized Gains (Losses) Arising During the Period	(3,185)	(11,289)	(3,310)
(Gain) Loss on Sale, Net of Tax			(115)
Amortization of Unrealized Holding (Gains) Losses on HTM Securities after Tax	1,199	971	1,300
Net Unrealized Gains (Losses) on Investment Securities	(1,986)	(10,318)	(2,125)
Net Actuarial Losses Arising During the Period	535	(577)	4,466
Amortization of Net Actuarial Losses (Gains)	837	741	983
Amortization of Prior Service Credit	(195)	(195)	(195)
Defined Benefit Plans, Net	1,177	(31)	5,254
Other Comprehensive Income (Loss)	$ (809)	$ (10,349)	$ 3,129