Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net Income	$ 35,184	$ 30,064	$ 28,344
Unrealized Gains (Losses) on Securities:
Unrealized Holding Gain (Loss) Arising During the Period	(13,830)	2,153	14,146
Reclassification Adjustment for Gains Included in Net Income	(1,979)	(725)	(1,481)
Tax Effect	5,607	(496)	(4,476)
Net of Tax	(10,202)	932	8,189
Defined Benefit Pension Plans and Postretirement Benefit Obligation
Total Other Comprehensive Income (Loss)	(10,216)	922	8,153
COMPREHENSIVE INCOME	24,968	30,986	36,497
Postretirement Benefit Obligation:
Defined Benefit Pension Plans and Postretirement Benefit Obligation
Net (Loss) Arising During the Period	(24)	(22)	(96)
Reclassification Adjustment for Amortization of Prior Service Cost and Net Loss Included in Net Periodic Pension Cost	6	5	50
Tax Effect	4	7	10
Net of Tax	$ (14)	$ (10)	$ (36)