Revenues - Contract with Customer, Asset and Liability (Details) - USD ($)	9 Months Ended
	Jul. 31, 2020	Oct. 31, 2019
Revenue from Contract with Customer [Abstract]
Billed trade receivables	$ 829,300,000	$ 978,700,000
Unbilled trade receivables	52,200,000	56,900,000
Costs incurred in excess of amounts billed	72,500,000	72,600,000
Capitalized commissions	22,600,000	$ 21,800,000
Capitalized contract price	10,600,000
Capitalized contract cost, amortization	(9,800,000)
Capitalized contract cost, impairment loss	0
Contract with Customer, Liabilities [Roll Forward]
Contract liabilities, balance at beginning of period	38,000,000.0
Additional contract liabilities	246,100,000
Recognition of deferred revenue	(241,700,000)
Contract liabilities, balance at end of period	$ 42,300,000