Revenues - Contract with Customer, Asset and Liability (Details) - USD ($)	3 Months Ended
	Jan. 31, 2021	Oct. 31, 2020
Revenue from Contract with Customer [Abstract]
Billed trade receivables	$ 896,800,000	$ 835,800,000
Unbilled trade receivables	58,300,000	53,900,000
Costs incurred in excess of amounts billed	38,600,000	52,200,000
Capitalized commissions	24,900,000	$ 25,200,000
Capitalized contract price	3,000,000.0
Capitalized contract cost, amortization	(3,300,000)
Capitalized contract cost, impairment loss	0
Contract with Customer, Liabilities [Roll Forward]
Contract liabilities, balance at beginning of period	36,400,000
Additional contract liabilities	31,500,000
Recognition of deferred revenue	(14,800,000)
Contract liabilities, balance at end of period	$ 53,100,000