Retirement Benefits (Amount of accumulated other comprehensive income expected to be recognized in next fiscal year) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012
US [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	$ 116.1
Prior service cost	2.6
International [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	27.7
Prior service cost	0.4
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	$ 4.2