Organization and summary of significant accounting policies - Compensation and benefits (Details) - Selling, general and administrative expenses - USD ($) $ in Millions	12 Months Ended
Feb. 01, 2020	Feb. 02, 2019	Feb. 03, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Wages and salaries	$ 1,079.2	$ 1,127.2	$ 1,140.3
Payroll taxes	84.8	90.3	93.8
Employee benefit plans	15.7	17.2	13.0
Share-based compensation	16.9	16.5	16.1
Total compensation and benefits	$ 1,196.6	$ 1,251.2	$ 1,263.2

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Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
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Amount of cost (reversal of cost) for pension and other postretirement benefits.

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Amount of expense for salary and wage arising from service rendered by nonofficer and officer employees. Excludes allocated cost, labor-related nonsalary expense, and direct and overhead labor cost included in cost of good and service sold.

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