Supplemental Stockholders' Equity Information - Changes in Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2014	Jun. 30, 2013	Jun. 29, 2014		Jun. 30, 2013
Changes in accumulated other comprehensive income (loss):
Balance, beginning of period			$ (402,611)
Other comprehensive (loss)/income before reclassifications, before tax(1)			1,078	[1]
Amounts reclassified from accumulated other comprehensive loss, before tax			11,934
Income tax (benefit)/expense	2,440	3,672	5,141		5,452
Other comprehensive income, net of tax	3,977	4,899	7,871		7,527
Balance, end of period	(394,740)		(394,740)
Foreign Currency Translation Adjustments [Member]
Changes in accumulated other comprehensive income (loss):
Balance, beginning of period			12,674
Other comprehensive (loss)/income before reclassifications, before tax(1)			(582)	[1]
Amounts reclassified from accumulated other comprehensive loss, before tax			0
Income tax (benefit)/expense			(251)
Other comprehensive income, net of tax			(331)
Balance, end of period	12,343		12,343
Funded Status of Benefit Plans [Member]
Changes in accumulated other comprehensive income (loss):
Balance, beginning of period			(415,285)
Other comprehensive (loss)/income before reclassifications, before tax(1)			1,660	[1]
Amounts reclassified from accumulated other comprehensive loss, before tax			11,934
Income tax (benefit)/expense			5,392
Other comprehensive income, net of tax			8,202
Balance, end of period	$ (407,083)		$ (407,083)

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