STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 223.0	$ 152.2	$ 252.4
Other Comprehensive Income (Loss), net of tax:
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	(36.5)	(10.4)	12.5
Foreign currency translation adjustment	34.7	(40.1)	(24.0)
Change in pension and postretirement defined benefit plans	4.1	(13.6)	8.5
Total Other Comprehensive Income (Loss), net of tax	(2.3)	64.1	3.0
Total Comprehensive Income	$ 225.3	$ 88.1	$ 249.4