Employee Benefits - Schedule of Components of Net Periodic Defined Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Retirement Benefits [Abstract]
Service cost	$ 2.2	$ 2.7	$ 7.6	$ 8.1
Interest cost	2.1	1.3	4.6	3.8
Expected return on plan assets	(2.8)	(2.3)	(7.4)	(6.9)
Recognized net actuarial loss	(0.2)	0.4	0.6	1.2
Net periodic pension cost	$ 1.3	$ 2.1	$ 5.4	$ 6.2