Prior Year Misstatement Correction in the Current Year (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2016	Apr. 30, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales	$ 571.3	$ 575.6	$ 1,626.5	$ 1,760.6
Cost of sales	374.7	381.5	1,081.0	1,154.3
Gross profit	196.6	194.1	545.5	606.3
Operating income	74.9	67.1	184.1	209.9
Earnings before income taxes	72.1	67.8	174.9	210.5
Income taxes	17.3	20.0	43.6	58.8
Net earnings	$ 54.8	$ 47.8	$ 131.3	$ 151.7
Basic earnings per share (in usd per share)	$ 0.41	$ 0.35	$ 0.98	$ 1.10
Diluted earnings per share (in usd per share)	$ 0.41	$ 0.34	$ 0.97	$ 1.08
Comprehensive income	$ 94.0	$ 47.0	$ 123.1	$ 67.8
Accelerated Revenue Recognition
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		575.6		1,760.6
Cost of sales		381.5		1,154.3
Gross profit		194.1		606.3
Operating income		67.1		209.9
Earnings before income taxes		67.8		210.5
Income taxes		20.0		58.8
Net earnings		$ 47.8		$ 151.7
Basic earnings per share (in usd per share)		$ 0.35		$ 1.10
Diluted earnings per share (in usd per share)		$ 0.34		$ 1.08
Comprehensive income		$ 47.0		$ 67.8
Accelerated Revenue Recognition | As Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		568.0		1,761.4
Cost of sales		376.0		1,154.8
Gross profit		192.0		606.6
Operating income		65.0		210.2
Earnings before income taxes		65.7		210.8
Income taxes		19.3		58.9
Net earnings		$ 46.4		$ 151.9
Basic earnings per share (in usd per share)		$ 0.34		$ 1.10
Diluted earnings per share (in usd per share)		$ 0.33		$ 1.08
Comprehensive income		$ 45.6		$ 68.0
Accelerated Revenue Recognition | Effect of Revision
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net sales		7.6		(0.8)
Cost of sales		5.5		(0.5)
Gross profit		2.1		(0.3)
Operating income		2.1		(0.3)
Earnings before income taxes		2.1		(0.3)
Income taxes		0.7		(0.1)
Net earnings		$ 1.4		$ (0.2)
Basic earnings per share (in usd per share)		$ 0.01		$ 0.00
Diluted earnings per share (in usd per share)		$ 0.01		$ 0.00
Comprehensive income		$ 1.4		$ (0.2)