Schedule II-Valuation and Qualifying Accounts (Detail) - Accounts receivable allowances - USD ($) $ in Millions	12 Months Ended
Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance Beginning of Year	$ 19.2	$ 25.5	$ 18.1
Charges to Costs and Expenses	87.7	57.4	47.4
Write-offs/Allowance Taken	(84.6)	(63.6)	(40.0)
Balance End of Year	$ 22.4	$ 19.2	$ 25.5

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

+ References

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

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