Basis of presentation and accounting policies - Impairment, Goodwill, Balance sheet detail (Detail) - USD ($)	12 Months Ended
	Feb. 03, 2017	Jan. 29, 2016	Jan. 30, 2015
Impairment of long-lived assets
Minimum period for which stores are open to be reviewed for impairment	3 years
Impairment charges included in SG&A expense	$ 6,300,000	$ 5,900,000	$ 1,900,000
Goodwill and other intangible assets
Impairment of intangible assets	0	0	$ 0
Accrued expenses and other liabilities
Compensation and benefits	91,243,000	111,191,000
Insurance	85,240,000	82,182,000
Taxes (other than taxes on income)	175,099,000	136,762,000
Other	149,284,000	136,987,000
Accrued expenses and other	500,866,000	467,122,000
Operating leases and related liabilities
Deferred rent liability	61,100,000	57,900,000
Contingent rent liability	3,500,000	4,000,000
Noncurrent Other liabilities
Insurance	137,743,000	137,798,000
Deferred rent	61,082,000	57,017,000
Deferred gain on sale leaseback	49,259,000	53,737,000
Other	31,698,000	26,731,000
Noncurrent other liabilities	$ 279,782,000	$ 275,283,000