Restructuring and Related Costs - Restructuring and Related Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2019	Jan. 31, 2018
Restructuring Reserve [Roll Forward]
Balance, beginning of period	$ 8.6
Costs recognized	3.8	$ 14.3
Payments	(3.5)
Balance, end of period	8.9
Employee Severance
Restructuring Reserve [Roll Forward]
Balance, beginning of period	3.8
Costs recognized	1.3
Payments	(1.7)
Balance, end of period	3.4
Lease Exit
Restructuring Reserve [Roll Forward]
Balance, beginning of period	3.1
Costs recognized	0.0
Payments	(0.3)
Balance, end of period	2.8
Other Project Fees
Restructuring Reserve [Roll Forward]
Balance, beginning of period	1.8
Costs recognized	2.5
Payments	(1.5)
Balance, end of period	$ 2.7