Organization and summary of significant accoutning policies - Compensation and benefits (Details) - Selling, general and administrative expenses - USD ($) $ in Millions	12 Months Ended
Feb. 02, 2019	Feb. 03, 2018	Jan. 28, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Wages and salaries	$ 1,127.2	$ 1,140.3	$ 1,183.2
Payroll taxes	90.3	93.8	96.5
Employee benefit plans	17.2	13.0	19.3
Share-based compensation	16.5	16.1	8.0
Total compensation and benefits	$ 1,251.2	$ 1,263.2	$ 1,307.0

Payroll Tax Expense

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(4))
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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