Financial Instruments (Schedule of Outstanding Currency Price Risk Management Instruments) (Details) - Forward Exchange Contracts [Member] - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Jun. 30, 2017	Sep. 30, 2016
Derivative [Line Items]
US$ Notional	$ 5,137.3	$ 7,746.8
Years Average Maturity	8 months	8 months
Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
US$ Notional	$ 1,220.4	$ 2,648.3
Years Average Maturity	1 month	5 months
Cash Flow Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
US$ Notional	$ 3,209.4	$ 4,130.3
Years Average Maturity	5 months	6 months
Net Investment Hedges [Member] | Designated as Hedging Instrument [Member]
Derivative [Line Items]
US$ Notional	$ 707.5	$ 968.2
Years Average Maturity	3 years	2 years 8 months