Earnings Per Share - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Jul. 28, 2012	Jul. 30, 2011
Earnings Per Share Disclosure [Line Items]
Equity awards to purchase shares of common stock that were not included in the computation of weighted average diluted common share amounts as the effect of doing so would have been anti-dilutive	2,900,000	7,500,000	3,400,000	7,200,000
Restricted Stock Units (RSUs)
Earnings Per Share Disclosure [Line Items]
Shares of restricted stock units not included in the computation of weighted average diluted common share amounts because the number of shares ultimately issued is contingent on performance	30,000.0	1,900,000	30,000.0	1,900,000