Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
	Mar. 27, 2012	Sep. 25, 2012 item supplier	Dec. 27, 2011
Commitments and Contingencies
Estimated cost to complete capital project commitments (in dollars)		$ 55.9	$ 58.6
Ownership percentage		5.00%
Number of suppliers providing most of the company's beef		4
Minimum age specified in age discrimination allegation against entity		40 years
Number of motions filed by the entity in response to a complaint filed by the EEOC		2
Number of motions filed by the entity to dismiss a case filed by the EEOC		1
Number of motions filed by the entity to transfer a case filed by the EEOC		1
Settlement expense	$ 5.0