Retirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified				6 Months Ended		3 Months Ended		6 Months Ended
	Aug. 30, 2013	Feb. 28, 2013	Aug. 24, 2012	Aug. 30, 2013 Profit-Sharing Plan [Member]	Aug. 24, 2012 Profit-Sharing Plan [Member]	Aug. 30, 2013 Defined Contribution Plans [Member] Domestic [Member]	Aug. 24, 2012 Defined Contribution Plans [Member] Domestic [Member]	Aug. 30, 2013 Defined Contribution Plans [Member] Domestic [Member]	Aug. 24, 2012 Defined Contribution Plans [Member] Domestic [Member]
Defined Benefit Plan Disclosure [Line Items]
Corporate contributions to the profit-sharing plan				$ 4.5	$ 3.4	$ 1.4	$ 1.3	$ 2.7	$ 2.6
Liability for postretirement benefits other than pensions	17.6	15.7	27.7
Long-term liability for pension benefits	$ 86.3	$ 81.4	$ 75.6