Employee Benefits - Schedule of Components of Net Periodic Defined Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Retirement Benefits [Abstract]
Service cost	$ 4.3	$ 3.5
Interest cost	1.1	1.2
Expected return on plan assets	(3.1)	(2.7)
Recognized net actuarial gain	1.3	1.0
Net periodic defined benefit plan cost	$ 3.6	$ 3.0