PROPERTY, PLANT AND EQUIPMENT (Schedule of Property, Plant and Equipment) (Details) - USD ($) $ in Thousands	Dec. 27, 2015	Dec. 28, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 3,100,144	$ 2,873,069
Accumulated depreciation	(1,747,615)	(1,690,274)
Property, plant and equipment, net	1,352,529	1,182,795
Land [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	105,165	66,798
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,131,379	1,086,690
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	1,657,573	1,537,241
Autos and trucks [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	53,408	52,639
Construction-in-progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 152,619	$ 129,701