Pension and Postretirement Benefit Plans (Narrative) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) employee	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Retired employees receiving health care and life insurance benefits | employee	9
Post retirement benefits, age eligibility requirement	65 years
Post retirement benefits, service eligibility requirement	15 years
Unrecognized net actuarial gain	$ 39
Recognized transition obligation	$ 2
Annual rate of increase in cost of covered health care benefits, next fiscal year	10.00%
Annual rate of increase in cost of covered health care benefits, two fiscal years	10.00%
Annual rate of increase in cost of covered health care benefits, three fiscal years	8.00%
Annual rate of increase in cost of covered health care benefits, four fiscal years	8.00%
Annual rate of increase in cost of covered health care benefits, five fiscal years and thereafter	6.00%
Postretirement Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ (2)	$ (4)	$ (3)
Unrecognized net actuarial gain	$ 6	$ (1)	$ 9
Benefit obligation weighted average discount rate	3.00%	3.50%	2.75%
Effect of 1% rate increase on benefit obligation	$ 5
Effect of 1% rate increase on net periodic benefit cost (less than one thousand)	1
Effect of 1% rate decrease on benefit obligation	(4)
Effect of 1% rate decrease on net periodic benefit cost (less than one thousand)	$ 1