Commitments and contingencies (Details) (USD $)	1 Months Ended	12 Months Ended
	Jan. 29, 1999	Feb. 01, 2013	Feb. 03, 2012	Jan. 28, 2011	Aug. 31, 2007
Commitments and contingencies
Typical period of primary lease term for operating lease, build-to-suit, minimum		10 years
Typical period of primary lease term for operating lease, build-to-suit, maximum		15 years
Period for which asset was taken on lease under sale and leaseback transaction	23 years
Face value of promissory note purchased					$ 34,300,000
Future minimum payments for operating leases
2013		611,595,000
2014		568,029,000
2015		509,684,000
2016		452,756,000
2017		399,708,000
Thereafter		1,993,446,000
Total minimum payments		4,535,218,000
Total minimum payments for capital leases		10,100,000
Present value of net minimum capital lease payments		7,700,000
Effective interest rate at which capital leases are discounted (as a percent)		6.20%
Gross property and equipment recorded under capital lease		29,800,000	29,000,000
Accumulated depreciation on property and equipment recorded under capital lease		6,900,000	7,300,000
Operating lease rent expenses
Minimum rentals		599,138,000	525,486,000	471,402,000
Contingent rentals		15,150,000	16,856,000	17,882,000
Operating lease rent expenses		614,288,000	542,342,000	489,284,000
Goodwill and other intangible assets
Amortization expense		16,900,000	21,000,000	27,400,000
Finite lived intangible assets excluding internally developed software
Goodwill and other intangible assets
Amortization expense		$ 16,900,000	$ 21,000,000	$ 25,700,000