Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Effective tax rate	25.90%	28.50%	24.40%	15.90%
Federal statutory rate			21.00%		24.50%
Net benefit recorded as a result of the U.S. tax reform				$ 22.2
Unremitted earnings of foreign operations	$ 3.0		$ 3.0
Reversal amount of tax benefit as a result of change in the regulations			$ 2.5