Stock Compensation - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions	3 Months Ended
Jan. 31, 2018	Jan. 31, 2017
New Accounting Pronouncement, Early Adoption [Line Items]
Share-based compensation, excess tax benefit, amount	$ 7.5
Unamortized share-based compensation expense	$ 243.5
Weighted-average period of total compensation costs to be recognized in years	2 years 6 months
Other Assumed Stock Plans [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Share Based Compensation Arrangement Assumed Stock Plans Remaining Outstanding Shares		0.4

Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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- Definition

Share based compensation arrangement assumed stock plans remaining outstanding shares.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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.

+ References

No definition available.

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