Employee Benefit Plans (Details) - Pension Benefits [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Components of net periodic cost (benefit) for pension and postretirement plans
Service cost	$ 88	$ 52
Interest cost	235	246
Expected return on plan assets	(282)	(284)
Defined Benefit Plan Amortization Of Actuarial Loss Gain And Prior Service Cost Credit	184	206
Net periodic cost recognized	$ 225	$ 220