Segment reporting (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Nov. 03, 2017 USD ($) segment	Oct. 28, 2016 USD ($) segment	Nov. 03, 2017 USD ($) segment	Oct. 28, 2016 USD ($) segment
Net sales data for classes of similar products
Net sales	$ 5,903,606	$ 5,320,029	$ 17,341,536	$ 15,977,352
Number of reportable segments
Number of reportable operating segments | segment	1	1	1	1
Consumables
Net sales data for classes of similar products
Net sales	$ 4,625,401	$ 4,137,748	$ 13,425,273	$ 12,293,395
Seasonal
Net sales data for classes of similar products
Net sales	636,519	575,912	2,017,150	1,873,715
Home products
Net sales data for classes of similar products
Net sales	346,339	329,715	1,007,137	968,161
Apparel
Net sales data for classes of similar products
Net sales	$ 295,347	$ 276,654	$ 891,976	$ 842,081