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Stock Compensation - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Jan. 31, 2017 | Nov. 01, 2016
New Accounting Pronouncement, Early Adoption [Line Items] |  |
Unamortized share-based compensation expense | $ 189.5 |
Weighted-average period of total compensation costs to be recognized in years | 2 years 7 months 6 days |
Accounting Standards Update 2016-09, Forfeiture Rate Component | Retained Earnings | New Accounting Pronouncement, Early Adoption, Effect |  |
New Accounting Pronouncement, Early Adoption [Line Items] |  |
Cumulative effect adjustment |  | $ 0.4

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