Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net Income	$ 28.5	$ 34.0	$ 116.8	$ 57.5
Other Comprehensive (Loss) Income, net of tax (Note 7):
Derivative instruments and hedges	7.9	(0.2)	11.3	10.0
Foreign currency translation adjustment	16.5	14.0	22.6	(25.5)
Change in pension and postretirement defined benefit plans	0.8	0.8	1.6	2.1
Total Other Comprehensive Income (Loss), net of tax	25.2	14.6	35.5	(13.4)
Total Comprehensive Income	53.7	48.6	152.3	44.1
Net Income (Loss) Attributable to Noncontrolling Interest	0.0	(0.4)	0.0	(0.7)
Total Comprehensive Income Attributable to Common Shareholders	$ 53.7	$ 49.0	$ 152.3	$ 44.8