Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Sep. 30, 2015
Income Tax Disclosure [Abstract]
Effective income tax rate	24.30%	27.60%	22.90%	26.20%
U.S. statutory rate	35.00%	35.00%	35.00%	35.00%
Gross unrecognized tax benefits	$ 27.3		$ 27.3		$ 43.9
Accrued interest and penalties related to unrecognized tax benefits	4.5		4.5		$ 5.1
Reasonably possible amount of reduction in gross unrecognized tax benefits for the next twelve months	$ 1.5		$ 1.5
Earliest open year for income tax examinations, U.S. federal			2014
Earliest open tax year for income tax examinations, state, local and non-U.S.			2003