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Goodwill and Intangible Assets - Impairment Analysis (Details) | Jan. 25, 2020 | Jan. 26, 2019 | Jan. 27, 2018 | Jul. 29, 2017
--- | --- | --- | --- | ---
Terminal Growth Rate |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Indefinite-lived Intangible Asset, Measurement Input | 0.030 |  |  |
Discount Rate |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Indefinite-lived Intangible Asset, Measurement Input | 0.100 | 0.110 | 0.110 | 0.110
Maximum | Terminal Growth Rate |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Indefinite-lived Intangible Asset, Measurement Input |  | 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

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