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Share-Based Compensation - Summary of Employee Restricted Stock Unit Award Grants (Details) - $ / shares | 3 Months Ended | 12 Months Ended
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Apr. 29, 2018 | Jan. 27, 2019 | Jan. 28, 2018 | Jan. 29, 2017
Employee stock unit awards |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Stock units granted (in shares) |  |  | 998,000 |  | 983,000 |  | 1,228,000 |
Weighted average fair value units granted (in dollars per share) |  |  | $ 45.36 |  | $ 36.96 |  | $ 22.12 |
Performance shares |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Stock units granted (in shares) |  | 200,442 | 287,000 | [1] | 215,857 | [1] | 231,000 | [1]
Weighted average fair value units granted (in dollars per share) | [1] |  | $ 32.93 |  | $ 39.55 |  | $ 17.51 |
Subject to cash settlement | Performance shares |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Stock units granted (in shares) |  |  | 146,827 |  | 0 |  | 115,500 |
[1] | Restricted stock units granted includes awards that will be cash settled of 146,827 units in fiscal year 2019, 0 units in fiscal year 2018, and 115,500 units in fiscal year 2017.

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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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. + Details
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