Accumulated Other Comprehensive Income (Loss) (Changes in AOCI Components) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance			$ (103,229)
Other comprehensive income before reclassifications			508
Amounts reclassified from AOCI			3,189
Total other comprehensive income	$ 1,650	$ 2,323	3,697	$ 6,545
Accumulated Other Comprehensive Loss, Ending balance	(99,532)		(99,532)
Foreign Currency Translation [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance			(5,255)
Other comprehensive income before reclassifications			508
Amounts reclassified from AOCI			0
Total other comprehensive income			508
Accumulated Other Comprehensive Loss, Ending balance	(4,747)		(4,747)
Pension and Other Postretirement Benefits [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance			(97,974)
Other comprehensive income before reclassifications			0
Amounts reclassified from AOCI			3,189
Total other comprehensive income			3,189
Accumulated Other Comprehensive Loss, Ending balance	$ (94,785)		$ (94,785)