Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Income Taxes [Line Items]
Cash paid for taxes (net of cash refunds)		$ 392.9	$ 160.6	$ 325.5
U.S. federal statutory tax rate		35.00%	35.00%	35.00%
Goodwill impairment charge	$ 305.2		$ 305.2
Goodwill impairment charge deductible for tax purposes			0.0
Tax credits and other tax carryforwards	78.1	$ 43.8	78.1
Tax loss carryforwards	125.0	116.7	125.0
Deferred tax assets, valuation allowance	103.8	103.6	103.8
Cumulative undistributed earnings		$ 6,361.1
Percentage of the undistributed earnings in countries with a statutory tax rate of 24% or higher		80.00%
Statutory tax rate percentage or higher		24.00%
US Income and foreign withholding taxes estimate		$ 1,593.0
Unrecognized tax benefits	108.7	97.5	108.7	$ 124.3	$ 110.8
Unrecognized tax benefits that would impact effective tax rate	66.5	62.5	66.5
Interest and penalties related to unrecognized tax benefits		(1.8)	1.2	2.4
Accrued interest and penalties	$ 9.3	7.5	9.3
Unrecognized tax benefits, decreases resulting from prior period tax positions		7.9	14.6	0.5
Unrecognized tax benefits,decreases resulting from settlements with taxing authorities		0.6	$ 0.0	$ 1.4
Chilean Tax Rate Change [Member]
Income Taxes [Line Items]
Effective income tax rate reconciliation, change in enacted tax rate			1.50%
Income tax expense from tax reform			$ 20.6
Non-U.S. Subsidiary Tax Election [Member]
Income Taxes [Line Items]
Increase (decrease) in income tax expense			$ (51.6)
Federal [Member]
Income Taxes [Line Items]
Capital loss carryforwards		146.5
Tax credit carryforwards		12.6
Tax loss carryforwards		$ 52.8
Federal [Member] | Capital Loss Carryforward [Member]
Income Taxes [Line Items]
Tax carryforward expiration period end		2019
Tax loss carryforwards		$ 51.3
Federal [Member] | Tax Credit Carryforward [Member]
Income Taxes [Line Items]
Tax carryforward expiration period start		2025
Foreign [Member]
Income Taxes [Line Items]
Tax credit carryforwards		$ 27.2
Operating loss carryforwards		239.8
Unused carryforwards and credits that have an expiration period		$ 154.4
Foreign [Member] | Loss and Tax Credit Member [Member]
Income Taxes [Line Items]
Tax carryforward expiration period start		2016
Tax carryforward expiration period end		2035
State [Member]
Income Taxes [Line Items]
Tax credit carryforwards		$ 4.0
Operating loss carryforwards		$ 134.3
State [Member] | Loss and Tax Credit Member [Member]
Income Taxes [Line Items]
Tax carryforward expiration period start		2016
Tax carryforward expiration period end		2034