Pension and Other Postretirement Benefit Plans Schedule of Amounts Recognized in Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Other Assets, Noncurrent	$ 47,124	$ 43,607
Deferred Tax Assets, Net	35,367	32,604
Other Liabilities, Noncurrent	44,716	48,853
Accumulated Other Comprehensive Income (Loss), Net of Tax	(9,828)	(10,538)
Dutch Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred Tax Assets, Net	2,328	2,660
Other Liabilities, Noncurrent	9,948	9,643
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (9,169)	$ (9,540)