Property, Plant and Equipment (Schedule of Property, Plant and Equipment) (Details) - USD ($) $ in Thousands	Mar. 28, 2015	Dec. 27, 2014
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 755,504	$ 762,248
Accumulated depreciation	(480,076)	(479,840)
Property, plant and equipment, net	275,428	282,408
Land and land improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	13,995	13,982
Building and building improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	101,245	101,407
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	614,498	623,619
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	9,554	10,086
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 16,212	$ 13,154