Goodwill and Other Intangible Assets (Reconciliation of Intangible Assets) (Details) - USD ($) $ in Millions	9 Months Ended
	Apr. 30, 2018	Jul. 31, 2017
Finite-lived Intangible Assets [Roll Forward]
Gross carrying amount, net intangible assets	$ 107.7	$ 106.6
Accumulated amortization, net intangible assets	(70.6)	(66.0)
Amortization expense	(4.1)
Foreign currency translation gain (loss), gross carrying amount	1.1
Foreign exchange translation, accumulated amortization	(0.5)
Ending balance, foreign currency translation gain (loss)	0.6
Ending balance, net intangible assets	$ 37.1	$ 40.6