Equity Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2017	Apr. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)			888,500
Options granted, grant date fair value (in usd per share)			$ 10.09	$ 7.10
Pre-tax stock-based compensation expense associated with stock options	$ 1.3	$ 1.2	$ 6.2	$ 5.6
Tax benefit associated with stock options	0.3	$ 0.3	1.9	1.7
Total intrinsic value of options exercised			13.8	$ 7.4
Aggregate intrinsic value of options outstanding	95.9		95.9
Aggregate intrinsic value of options exercisable	79.3		79.3
2010 Master Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested stock options granted	$ 8.7		$ 8.7