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Income Taxes - Narratives (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
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Jul. 25, 2020 | Jul. 27, 2019 | Jul. 25, 2020 | Jul. 27, 2019
Income Tax Disclosure [Abstract] |  |  |  |
Effective tax rate | 24.90% | 29.80% | 76.40% | 30.00%
CARES Act tax benefit, tax loss carryback |  |  | $ 2.6 |

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