Segment reporting (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 31, 2020 USD ($)	Nov. 01, 2019 USD ($)	Aug. 02, 2019 USD ($)	May 03, 2019 USD ($)	Feb. 01, 2019 USD ($)	Nov. 02, 2018 USD ($)	Aug. 03, 2018 USD ($)	May 04, 2018 USD ($)	Jan. 31, 2020 USD ($) segment	Feb. 01, 2019 USD ($) segment	Feb. 02, 2018 USD ($) segment
Net sales data for classes of similar products
Net sales	$ 7,157,642	$ 6,991,393	$ 6,981,753	$ 6,623,185	$ 6,649,809	$ 6,417,462	$ 6,443,309	$ 6,114,463	$ 27,753,973	$ 25,625,043	$ 23,470,967
Number of reportable segments
Number of reportable operating segments | segment									1	1	1
Consumables
Net sales data for classes of similar products
Net sales									$ 21,635,890	$ 19,865,086	$ 18,054,785
Seasonal
Net sales data for classes of similar products
Net sales									3,258,874	3,050,282	2,837,310
Home products
Net sales data for classes of similar products
Net sales									1,611,899	1,506,054	1,400,618
Apparel
Net sales data for classes of similar products
Net sales									$ 1,247,310	$ 1,203,621	$ 1,178,254