Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Feb. 22, 2013	Nov. 23, 2012	Aug. 24, 2012	May 25, 2012	Feb. 24, 2012	Nov. 25, 2011	Aug. 26, 2011	May 27, 2011	Feb. 22, 2013	Feb. 24, 2012	Feb. 25, 2011
Earnings Per Share [Abstract]
Net income	$ (27.5)	$ 23.6	$ 29.5	$ 13.2	$ 14.9	$ 22.4	$ 11.9	$ 7.5	$ 38.8	$ 56.7	$ 20.4
Adjustment for earnings attributable to participating securities									(0.6)	(1.0)	(0.3)
Net income used in calculating earnings per share									$ 38.2	$ 55.7	$ 20.1
Weighted-average common shares outstanding including participating securities (in millions)									127.4	131.9	132.9
Adjustment for participating securities (in millions)									(1.8)	(2.3)	(2.0)
Shares used in calculating basic earnings per share (in millions)									125.6	129.6	130.9
Effect of dilutive stock-based compensation (in millions)									1.7	0	0
Shares used in calculating diluted earnings per share (in millions)									127.3	129.6	130.9
Earnings per share, basic	$ (0.22)	$ 0.19	$ 0.23	$ 0.10	$ 0.11	$ 0.17	$ 0.09	$ 0.06	$ 0.30	$ 0.43	$ 0.15
Earnings per share, diluted	$ (0.22)	$ 0.18	$ 0.23	$ 0.10	$ 0.11	$ 0.17	$ 0.09	$ 0.06	$ 0.30	$ 0.43	$ 0.15
Total common shares outstanding at period end (in millions)	125.2				126.5				125.2	126.5	132.2
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount									0	3.5	3.3