Segment reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jul. 29, 2011	Jul. 30, 2010	Jul. 29, 2011 ReportableSegments	Jul. 30, 2010 ReportableSegments
Segment reporting
Number of reportable segments			1	1
Segment reporting
Net sales	$ 3,575,194	$ 3,214,155	$ 7,026,891	$ 6,325,469
Consumables
Segment reporting
Net sales	2,611,070	2,297,374	5,140,140	4,528,874
Seasonal
Segment reporting
Net sales	502,569	471,185	959,626	901,236
Home products
Segment reporting
Net sales	235,803	222,459	470,011	447,326
Apparel
Segment reporting
Net sales	$ 225,752	$ 223,137	$ 457,114	$ 448,033