v3.20.4

Stock-based Compensation (Summary of Total Compensation Expense and Associated Income Tax Benefit) (Details) - USD ($) $ in Millions | 3 Months Ended
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Oct. 31, 2020 | Nov. 02, 2019
Share-based Payment Arrangement [Abstract] |  |
Compensation expense | $ 0.3 | $ 1.6
Income tax benefit | $ 0.0 | $ 0.0

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