Acquisitions - GCA Pro Forma Financial Information (Details) - USD ($) $ in Millions	12 Months Ended
Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Selling, general and administrative expenses excluded from pro forma	$ 436.6	$ 410.1	$ 395.0
GCA Holding Corp.
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Pro forma, Revenue	6,293.0	6,153.6
Pro forma, Net income (loss) from continuing operations	$ 90.4	$ (0.6)
Pro forma, statutory tax rate (percent)	41.00%	41.00%
GCA Holding Corp. \| Acquisition-related Costs
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Selling, general and administrative expenses excluded from pro forma	$ 24.2

Business Acquisition, Pro Forma Statutory Tax Rate

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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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- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311

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