Segment reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Feb. 03, 2012	Oct. 28, 2011	Jul. 29, 2011	Apr. 29, 2011	Jan. 28, 2011	Oct. 29, 2010	Jul. 30, 2010	Apr. 30, 2010	Feb. 03, 2012 ReportableSegments	Jan. 28, 2011 ReportableSegments	Jan. 29, 2010 ReportableSegments
Segment reporting
Number of reportable segments									1	1	1
Net sales data for classes of similar products
Net sales	$ 4,185,073	$ 3,595,224	$ 3,575,194	$ 3,451,697	$ 3,486,104	$ 3,223,427	$ 3,214,155	$ 3,111,314	$ 14,807,188	$ 13,035,000	$ 11,796,380
Consumables
Net sales data for classes of similar products
Net sales									10,833,735	9,332,119	8,356,381
Seasonal
Net sales data for classes of similar products
Net sales									2,051,098	1,887,917	1,711,471
Home products
Net sales data for classes of similar products
Net sales									1,005,219	917,638	869,772
Apparel
Net sales data for classes of similar products
Net sales									$ 917,136	$ 897,326	$ 858,756