Goodwill and Other Intangible Assets (Reconciliation of Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 31, 2018	Jul. 31, 2018	Oct. 31, 2017
Customer relationships and lists
Finite-lived Intangible Assets [Roll Forward]
Gross carrying amount, net intangible assets	$ 103.3	$ 63.0
Accumulated amortization, net intangible assets	(36.5)	(35.7)
Intangibles acquired	42.0
Amortization expense	(1.0)
Foreign currency translation gain (loss), gross carrying amount	(1.7)
Foreign exchange translation, accumulated amortization	0.2
Ending balance, foreign currency translation gain (loss)	(1.5)
Ending balance, net intangible assets	66.8	$ 27.3
Patents, trademarks and technology
Finite-lived Intangible Assets [Roll Forward]
Gross carrying amount, net intangible assets	49.4		$ 43.7
Accumulated amortization, net intangible assets	(34.9)		(35.4)
Intangibles acquired	6.8
Amortization expense	(0.4)
Foreign currency translation gain (loss), gross carrying amount	(1.1)
Foreign exchange translation, accumulated amortization	0.9
Ending balance, foreign currency translation gain (loss)	(0.2)
Ending balance, net intangible assets	$ 14.5		$ 8.3