Accumulated Other Comprehensive Income (Loss) (Changes in AOCI Components) (Details) $ in Thousands	6 Months Ended
	Jun. 27, 2015 USD ($)
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance	$ (98,197)
Other comprehensive loss before reclassifications	(1,239)
Amounts reclassified from AOCI	2,684
Other comprehensive (loss) income	1,445
Accumulated Other Comprehensive Loss, Ending balance	(96,752)
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance	(2,905)
Other comprehensive loss before reclassifications	(1,239)
Amounts reclassified from AOCI	0
Other comprehensive (loss) income	(1,239)
Accumulated Other Comprehensive Loss, Ending balance	(4,144)
Pension and Other Postretirement Benefits [Member]
Accumulated Other Comprehensive Income Loss [Roll Forward]
Accumulated Other Comprehensive Loss, Beginning balance	(95,292)
Other comprehensive loss before reclassifications	0
Amounts reclassified from AOCI	2,684
Other comprehensive (loss) income	2,684
Accumulated Other Comprehensive Loss, Ending balance	$ (92,608)