Restructuring and Related Costs - Restructuring and Related Liabilities (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Restructuring Reserve [Roll Forward]
Balance, beginning of period			$ 8.6
Costs Recognized	$ 2.0	$ 2.9	8.5	$ 22.5
Payments			(9.0)
Balance, end of period	8.1		8.1
Employee severance
Restructuring Reserve [Roll Forward]
Balance, beginning of period			3.8
Costs Recognized			3.4
Payments			(4.2)
Balance, end of period	3.0		3.0
Lease exit costs and asset impairment
Restructuring Reserve [Roll Forward]
Balance, beginning of period			3.1
Costs Recognized			0.7
Payments			(0.7)
Balance, end of period	3.0		3.0
Other project fees
Restructuring Reserve [Roll Forward]
Balance, beginning of period			1.8
Costs Recognized			3.7
Payments			(4.1)
Balance, end of period	1.4		1.4
External support fees
Restructuring Reserve [Roll Forward]
Balance, beginning of period			0.0
Costs Recognized			0.8
Payments			0.0
Balance, end of period	$ 0.8		$ 0.8