Basis of presentation and accounting policies - Impairment, Goodwill, Balance sheet detail (Details) - USD ($) $ in Thousands	12 Months Ended
Feb. 01, 2019	Feb. 02, 2018	Feb. 03, 2017
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	$ 4,100	$ 7,800	$ 6,300
Goodwill and other intangible assets
Impairment of intangible assets	0	0	$ 0
Accrued expenses and other liabilities
Compensation and benefits	121,375	118,755
Self-insurance reserves	107,380	96,277
Taxes (other than taxes on income)	183,941	164,451
Other	205,709	170,175
Accrued expenses and other	618,405	549,658
Operating leases and related liabilities
Deferred rent liability	70,100	65,900
Contingent rent liability	2,400	2,700
Noncurrent Other liabilities
Self-insurance reserves	130,022	134,256
Deferred rent	70,139	65,856
Deferred gain on sale leaseback	40,303	44,781
Other	57,897	61,051
Noncurrent other liabilities	$ 298,361	$ 305,944

Represents the minimum period for which stores are open to be reviewed for impairment.

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Represents the contingent rent liability derived from specified sales based targets at the balance sheet date.

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The noncurrent portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

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Carrying value as of the Balance Sheet date of obligations incurred and payable for sales, use, payroll, excise, real, property and other taxes, other than income taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

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For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total loss recognized during the period from the impairment of goodwill plus the loss recognized in the period resulting from the impairment of the carrying amount of intangible assets, other than goodwill.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid within one year (or the normal operating cycle, if longer).

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Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid after one year (or the normal operating cycle, if longer).

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