Acquisitions - GCA Preliminary Purchase Price Allocation (Details) - USD ($) $ in Millions	12 Months Ended
	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Business Acquisition [Line Items]
Goodwill	$ 1,835.4	$ 1,834.8	$ 1,864.2
Acquired Intangible Assets
Amortization period for acquired intangible assets	12 years
GCA Holding Corp.
Business Acquisition [Line Items]
Cash and cash equivalents		0.2
Trade accounts receivable		116.3
Prepaid expenses and other current assets		12.0
Property, plant and equipment		37.3
Goodwill		926.9
Other assets		4.0
Trade accounts payable		(9.6)
Insurance reserves		(35.2)
Income taxes payable		(8.6)
Accrued liabilities		(38.8)
Deferred income tax liability, net		(85.6)
Other liabilities		(8.1)
Net assets acquired		1,258.8
Acquired Receivables
Trade accounts receivable, gross		121.9
Estimated uncollectible trade accounts receivable		5.6
GCA Holding Corp. | Customer relationships
Business Acquisition [Line Items]
Intangible assets		$ 340.0
Acquired Intangible Assets
Amortization period for acquired intangible assets		15 years
GCA Holding Corp. | Trade names
Business Acquisition [Line Items]
Intangible assets		$ 8.0
Acquired Intangible Assets
Amortization period for acquired intangible assets		2 years