Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net Income	$ 30,064	$ 28,344	$ 25,413
Unrealized Gains (Losses) on Securities
Unrealized Holding Gain (Loss) Arising During the Period	2,153	14,146	(22,169)
Reclassification Adjustment for Gains Included in Net Income	(725)	(1,481)	(2,429)
Tax Effect	(496)	(4,476)	8,724
Net of Tax	932	8,189	(15,874)
Defined Benefit Pension Plans and Postretirement Benefit Obligation
Total Other Comprehensive Income (Loss)	922	8,153	(15,614)
COMPREHENSIVE INCOME	30,986	36,497	9,799
Defined Benefit Pension Plans
Defined Benefit Pension Plans and Postretirement Benefit Obligation
Net Gain (Loss) Arising During the Period	0	0	749
Reclassification Adjustment for Amortization of Prior Service Cost and Net (Gain) Loss Included in Net Periodic Pension Cost	0	0	(373)
Tax Effect	0	0	(145)
Net of Tax	0	0	231
Postretirement Benefit Obligation
Defined Benefit Pension Plans and Postretirement Benefit Obligation
Net Gain (Loss) Arising During the Period	(22)	(96)	80
Reclassification Adjustment for Amortization of Prior Service Cost and Net (Gain) Loss Included in Net Periodic Pension Cost	5	50	(37)
Tax Effect	7	10	(14)
Net of Tax	$ (10)	$ (36)	$ 29