PROPERTY, PLANT AND EQUIPMENT (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 25, 2016	Sep. 27, 2015	Sep. 25, 2016	Sep. 27, 2015	Dec. 27, 2015
Property, Plant and Equipment [Abstract]
Depreciation	$ 42,800	$ 38,800	$ 124,700	$ 109,400
Payments for capital projects			173,440	129,848
Transfer of property, plant and equipment			158,500	101,500
Proceeds from property disposals	2,200	11,400	10,316	13,553
Net gain (loss) on property disposals	600	$ 8,500	7,315	$ 9,817
Assets held for sale	6,049		6,049		$ 6,555
Idled assets, carrying amount	63,100		63,100
Idled assets, depreciable value	193,100		193,100
Idled assets, accumulated depreciation	$ 130,000		$ 130,000