Income Taxes (Components of deferred tax assets and liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Components of Deferred Tax Assets and Liabilities [Abstract]
Net operating loss carryforwards	$ 111,899	$ 147,056
Income tax credits	41,900	27,212
Property, plant and equipment	21,860	21,921
Accrued liabilities	68,563	62,016
Unrealized foreign exchange loss	531	869
Other	14,583	16,659
Total deferred tax assets	259,336	275,733
Valuation allowance	(165,367)	(168,105)
Total deferred tax assets net of valuation allowance	93,969	107,628
Property, plant and equipment	20,407	31,345
Deferred gain	2,655	3,716
Other	5,826	6,713
Total deferred tax liabilities	28,888	41,774
Other assets	66,831	70,784
Other non-current liabilities	(1,750)	(4,930)
Net deferred tax assets	$ 65,081	65,854
Deferred tax assets related to equity compensation		$ 4,600