Supplemental Stockholders' Equity Information Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning				$ (533,795)
Income tax (benefit)/expense		$ 3,635	$ 9,410	24,211	$ 14,551
Other comprehensive income, net of tax		5,049	$ 13,886	36,333	21,757
Balance, ending		(497,513)		(497,513)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning				5,705
Other comprehensive income before reclassifications, before tax	[1]			(7,102)
Amounts reclassified from accumulated other comprehensive loss, before tax	[1]			0
Income tax (benefit)/expense	[1]			(2,540)
Other comprehensive income, net of tax				(4,562)
Balance, ending		1,143		1,143
Funded Status of Plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning				(539,500)
Other comprehensive income before reclassifications, before tax	[1]			0
Amounts reclassified from accumulated other comprehensive loss, before tax	[1]			67,595
Income tax (benefit)/expense	[1]			26,751
Other comprehensive income, net of tax				40,844
Balance, ending		(498,656)		(498,656)
Total Accumulated Other Comprehensive Loss
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance, beginning				(533,795)
Other comprehensive income before reclassifications, before tax	[1]			(7,102)
Amounts reclassified from accumulated other comprehensive loss, before tax	[1]			67,595
Income tax (benefit)/expense	[1]			24,211
Other comprehensive income, net of tax				36,282	$ 21,757
Balance, ending		$ (497,513)		$ (497,513)

[1] All amounts are shown net of noncontrolling interest.