Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Apr. 30, 2016	Jul. 31, 2015
Statement of Financial Position [Abstract]
Accounts receivable, allowance	$ 8.2	$ 6.7
Preferred stock, par value	$ 1.00	$ 1.00
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 5.00	$ 5.00
Common stock, shares authorized	240,000,000	240,000,000
Common stock, shares issued	151,643,194	151,643,194
Treasury stock, shares	18,534,433	17,044,950