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Goodwill and Intangible Assets - Impairment Analysis (Details)	Jan. 26, 2019	Jan. 27, 2018	Jul. 29, 2017	Jul. 30, 2016
Discount Rate
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Asset, Measurement Input	0.110	0.110	0.110	0.115
Maximum | Terminal Growth Rate
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Asset, Measurement Input	0.030	0.030	0.030	0.030
Minimum | Terminal Growth Rate
Acquired Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangible Asset, Measurement Input	0.025	0.025	0.020	0.020

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- Definition

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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.

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