Leases - Lease Cost (Details) $ in Millions	3 Months Ended
	Jan. 31, 2020 USD ($)
Operating lease costs:
Operating lease, cost	$ 26.6
Finance lease costs:
Operating expenses(4)	1.1
Interest expense(5)	0.1
Total lease costs	27.8
Short-term lease costs	14.5
Variable lease costs	2.0
Total short-term and variable lease costs	16.5
Operating expenses(1)(2)
Operating lease costs:
Operating lease, cost	21.0
Selling, general and administrative expenses(3)
Operating lease costs:
Operating lease, cost	$ 5.6