Commitments and contingencies (Details) (USD $)	1 Months Ended	12 Months Ended
	Jan. 29, 1999	Jan. 31, 2014 item	Feb. 01, 2013	Feb. 03, 2012	Aug. 31, 2007
Commitments and contingencies
Number of store locations sold and leased back		233
Period for which asset was taken on lease under sale and leaseback transaction	23 years	15 years
Cash proceeds under sale and leaseback transaction		$ 281,600,000
Deferred gain under sale and leaseback transaction		67,200,000
Face value of promissory note purchased					34,300,000
Future minimum payments for operating leases
2014		712,563,000
2015		665,193,000
2016		610,643,000
2017		554,413,000
2018		496,265,000
Thereafter		2,699,755,000
Total minimum payments		5,738,832,000
Total minimum payments for capital leases		8,700,000
Present value of net minimum capital lease payments		6,800,000
Gross property and equipment recorded under capital lease		29,800,000	29,800,000
Accumulated depreciation on property and equipment recorded under capital lease		8,700,000	6,900,000
Operating lease rent expenses
Minimum rentals		674,849,000	599,138,000	525,486,000
Contingent rentals		12,058,000	15,150,000	16,856,000
Operating lease rent expenses		686,907,000	614,288,000	542,342,000
Amortization expense		$ 11,900,000	$ 16,900,000	$ 21,000,000
Maximum
Commitments and contingencies
Typical period of primary lease term for operating lease, build-to-suit, maximum		15 years