FIXED ASSETS (Schedule Of Fixed Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Gross fixed assets	$ 941,921	$ 901,422
Accumulated depreciation	(446,090)	(399,472)
PP&E Net including assets held for sale	495,831	501,950
Fixed assets, net	495,798	501,884
Land and land improvements
Property, Plant and Equipment [Line Items]
Gross fixed assets	38,209	37,835
Buildings and building improvements
Property, Plant and Equipment [Line Items]
Gross fixed assets	192,210	192,874
Machinery, equipment and computer systems
Property, Plant and Equipment [Line Items]
Gross fixed assets	650,850	607,869
Trucks, trailers and automobiles
Property, Plant and Equipment [Line Items]
Gross fixed assets	33,350	32,723
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Gross fixed assets	4,612	4,720
Construction in progress
Property, Plant and Equipment [Line Items]
Gross fixed assets	19,968	22,098
Capital leases
Property, Plant and Equipment [Line Items]
Gross fixed assets	2,722	3,303
Fixed assets held for sale
Property, Plant and Equipment [Line Items]
Fixed assets held for sale	$ (33)	$ (66)