CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
Statement of Financial Position [Abstract]
Trade accounts receivable, allowances	$ 26.8	$ 26.0
Preferred stock, no par value
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, no par value
Common stock, shares authorized	199,000,000	199,000,000
Common stock, shares issued	88,457,634	88,457,634
Treasury stock, shares	22,752,381	23,291,738