Share-Based Compensation - Narrative (Details) $ in Millions	12 Months Ended
Feb. 03, 2018 USD ($) share_option_savings_plan shares	Jan. 28, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share option savings plans \| share_option_savings_plan	3
Omnibus Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance measurement period	3 years
Shares available for grant \| shares	7,000,000
Intrinsic value \| $	$ 55.0	$ 53.0
Executive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan period	10 years
Annual maximum percent of issued common shares issuable under share plan	10.00%
Discount from market price	15.00%
Employee Share Savings Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	24 months
Irish Sharesave Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	36 months
Minimum \| Employee Share Savings Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	24 months
Minimum \| Irish Sharesave Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	36 months
Maximum \| Employee Share Savings Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	27 months
Maximum \| Irish Sharesave Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	42 months

Number of Share Option Savings Plans

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- Definition

Period in which performance criteria measured

+ References

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- Definition

Share-based compensation plan period.

+ References

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- Definition

Share-based Compensation Plan, Annual Maximum Percent of Issued Common Shares Issuable under Share Plan

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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