Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($)	3 Months Ended		9 Months Ended	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Income	$ 49,200,000	$ 93,900,000	$ 195,100,000
Other Comprehensive (Loss) Income, net of tax (Note 7):
Derivative instruments designated as hedges	1,200,000	(6,700,000)	11,700,000	$ (32,400,000)
Foreign currency translation adjustment	11,700,000	17,100,000	26,500,000	8,600,000
Change in pension and postretirement defined benefit plans	800,000	1,000,000.0	(2,500,000)	5,900,000
Other Comprehensive Income (Loss), Net of Tax, Total	13,700,000	11,400,000	40,700,000	(29,700,000)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 62,900,000	$ 105,300,000	$ 235,800,000	$ 150,900,000