PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Long-lived assets
Property, plant and equipment, at cost	$ 1,165,687	$ 1,105,736
Land and improvements
Long-lived assets
Property, plant and equipment, at cost	93,258	85,724
Buildings and improvements
Long-lived assets
Property, plant and equipment, at cost	350,937	325,813
Machinery and equipment
Long-lived assets
Property, plant and equipment, at cost	588,439	564,171
Transportation equipment
Long-lived assets
Property, plant and equipment, at cost	23,682	22,423
Office furniture and equipment
Long-lived assets
Property, plant and equipment, at cost	82,025	77,453
Construction in progress
Long-lived assets
Property, plant and equipment, at cost	$ 27,346	$ 30,152