Other Postretirement Benefits (Amounts Recognized in the Consolidated Financial Statements) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued post retirement liability: Current portion	$ (372)	$ (395)	$ (415)
Accrued post retirement liability: Long term portion	(1,313)	(1,566)	(1,764)
Net amount recognized	(1,893)	(2,116)	(2,328)
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accrued post retirement liability: Current portion	(368)	(368)	(356)
Accrued post retirement liability: Long term portion	(7,781)	(7,834)	(5,544)
Pre-tax accumulated other comprehensive loss – unamortized post-retirement healthcare costs	4,251	4,521	2,256
Net amount recognized	$ (3,898)	$ (3,681)	$ (3,644)