Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Income Taxes [Abstract]
Income Tax Expense (Benefit)	$ 16.8	$ 7.5	$ 22.2	$ 13.7
Effective Income Tax Rate Reconciliation, Percent	30.00%	24.00%	29.00%	25.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate			21.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	0.60%
Effective Income Tax Rate Reconciliation, Deduction, Percent	0.40%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	0.70%		3.30%	0.50%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent			1.20%	1.30%