Segment reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Jan. 31, 2014	Nov. 01, 2013	Aug. 02, 2013	May 03, 2013	Feb. 01, 2013	Nov. 02, 2012	Aug. 03, 2012	May 04, 2012	Jan. 31, 2014 segment	Feb. 01, 2013 segment	Feb. 03, 2012 segment
Segment reporting
Number of reportable segments									1	1	1
Net sales data for classes of similar products
Net sales	$ 4,493,945	$ 4,381,838	$ 4,394,651	$ 4,233,733	$ 4,207,621	$ 3,964,647	$ 3,948,655	$ 3,901,205	$ 17,504,167	$ 16,022,128	$ 14,807,188
Consumables
Net sales data for classes of similar products
Net sales									13,161,825	11,844,846	10,833,735
Seasonal
Net sales data for classes of similar products
Net sales									2,259,516	2,172,399	2,051,098
Home products
Net sales data for classes of similar products
Net sales									1,115,648	1,061,573	1,005,219
Apparel
Net sales data for classes of similar products
Net sales									$ 967,178	$ 943,310	$ 917,136