Employee Retirement Plans (Components of Net Periodic Pension and Other Post-Retirement Benefit Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Interest cost	$ 66	$ 88	$ 80
Amortization of unrecognized prior service cost	14	15	14
Net periodic pension cost	$ 80	$ 103	$ 94
Discount rate	3.94%	3.74%	4.45%