Income taxes - Reconciliation of Statutory Tax Rate to Effective Tax Rate (Details)	12 Months Ended
Jan. 30, 2021	Feb. 01, 2020	Feb. 02, 2019
Income Tax Disclosure [Abstract]
US federal income tax rates	21.00%	21.00%	21.00%
US state income taxes	4.10%	3.10%	2.30%
Differences between US federal and foreign statutory income tax rates	0.10%	1.30%	0.30%
Expenditures permanently disallowable for tax purposes, net of permanent tax benefits	(4.70%)	3.30%	(0.80%)
Impact of global reinsurance arrangements	14.10%	(20.30%)	3.10%
Impact of global financing arrangements	0.00%	0.00%	4.20%
Impairment of goodwill	(2.40%)	7.50%	(13.40%)
Out of period adjustment	0.00%	0.00%	1.40%
CARES Act	111.90%	0.00%	0.00%
Valuation allowance	(55.50%)	0.00%	0.00%
Other items	(5.50%)	2.80%	0.00%
Effective tax rate	83.10%	18.70%	18.10%

Effective Income Tax Rate Reconciliation Benefit Of Intra Group Financing Arrangements

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Effective Income Tax Rate Reconciliation, Global Reinsurance Arrangements

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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Percentage of the difference, between reported income tax expense (benefit) and the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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