Restructuring and Related Costs - Reconciliation Restructuring (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Restructuring Cost and Reserve [Line Items]
Cumulative charges	$ 52.5		$ 52.5
Restructuring Reserve [Roll Forward]
Balance, at beginning of period			8.0
Restructuring and related expenses	5.8	$ 8.8	10.8	$ 16.0
Payments			(12.5)
Balance, at end of period	6.3		6.3
External Support Fees
Restructuring Cost and Reserve [Line Items]
Cumulative charges	20.5		20.5
Restructuring Reserve [Roll Forward]
Balance, at beginning of period			1.2
Restructuring and related expenses			4.6
Payments			(4.8)
Balance, at end of period	1.0		1.0
Employee Severance
Restructuring Cost and Reserve [Line Items]
Cumulative charges	14.3		14.3
Restructuring Reserve [Roll Forward]
Balance, at beginning of period			3.8
Restructuring and related expenses			1.0
Payments			(2.4)
Balance, at end of period	2.4		2.4
Other Project Fees
Restructuring Cost and Reserve [Line Items]
Cumulative charges	8.4		8.4
Restructuring Reserve [Roll Forward]
Balance, at beginning of period			0.5
Restructuring and related expenses			3.7
Payments			(3.8)
Balance, at end of period	0.4		0.4
Lease Exit
Restructuring Cost and Reserve [Line Items]
Cumulative charges	4.7		4.7
Restructuring Reserve [Roll Forward]
Balance, at beginning of period			2.5
Restructuring and related expenses			1.5
Payments			(1.5)
Balance, at end of period	2.5		2.5
Asset Impairment
Restructuring Cost and Reserve [Line Items]
Cumulative charges	$ 4.7		$ 4.7