PROPERTY, PLANT AND EQUIPMENT (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 27, 2015	Dec. 28, 2014	Dec. 29, 2013
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 146,400	$ 136,400	$ 135,500
Proceeds from property disposals	14,610	11,108	31,337
Gain (loss) on property disposals	10,400	1,400
Expenditures for capital projects	175,764	171,443	$ 116,223
Completed projects transferred from construction-in-progress to depreciable assets	153,500
Idled assets property, plant and equipment, net	70,200
Idled asset property, plant and equipment gross	199,400
Idled asset accumulated depreciation	129,100
Assets held for sale	$ 6,555	$ 1,419