Employee Benefit Plans (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended					1 Months Ended	12 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended		9 Months Ended
	Sep. 25, 2011	Sep. 26, 2010	Sep. 25, 2011	Sep. 26, 2010	Sep. 26, 2010 2009 Restructuring Plan [Member]	Sep. 26, 2010 2010 Restructuring Plan [Member]	Sep. 25, 2011 2011 Restructuring Plan [Member]	Jan. 31, 2011 Pension And Postretirement Healthcare Plan [Member]	Dec. 31, 2010 Pension And Postretirement Healthcare Plan [Member]	Jun. 30, 2011 Pension And Postretirement Healthcare Plan [Member]	Sep. 26, 2010 Pension And SERPA Benefits [Member]	Sep. 25, 2011 Pension And SERPA Benefits [Member]	Sep. 26, 2010 Pension And SERPA Benefits [Member]	Dec. 31, 2010 Pension And SERPA Benefits [Member]	Sep. 26, 2010 Postretirement Healthcare Benefits [Member]	Sep. 26, 2010 Postretirement Healthcare Benefits [Member]	Dec. 31, 2010 Postretirement Healthcare Benefits [Member]	Sep. 25, 2011 Postretirement Healthcare Benefits [Member]	Sep. 26, 2010 SERPA Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net curtailment loss (gain)				$ 27,100,000	$ 1,100,000	$ 28,200,000	$ 200,000				$ 15,505,000	$ 236,000	$ 15,505,000		$ 12,666,000	$ 11,643,000
Discount rate, Benefit obligations												5.76%		5.79%			5.28%	5.30%
Funded status adjustment									(900,000)
Other comprehensive income																	900,000
Other comprehensive income, net of tax		(70,586,000)	546,000	(70,586,000)										500,000
Increase in other comprehensive income																	900,000
Restructuring expense	12,429,000	67,476,000	49,022,000	145,837,000			8,200,000
Settlement and curtailment loss											476,000		3,058,000						3,100,000
Company contributions								200,000,000
Further contributions by company										$ 0