Retirement Benefits (Schedule of Net Periodic Benefit Cost) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
US [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 10.7	$ 13.0
Interest cost	32.7	29.2
Expected return on plan assets	(47.0)	(44.9)
Prior service cost amortization	0.7	0.7
Actuarial loss amortization	19.6	29.1
Special termination benefits	0.2	0
Other	0	0
Net periodic benefit cost	16.9	27.1
International [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	8.8	8.3
Interest cost	16.6	14.7
Expected return on plan assets	(19.2)	(18.3)
Prior service cost amortization	0.1	0.1
Actuarial loss amortization	8.8	6.8
Special termination benefits	0	0
Other	0.5	0.6
Net periodic benefit cost	15.6	12.2
Other Postretirement Benefit Plans, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.8	1.0
Interest cost	0.6	0.5
Expected return on plan assets	0	0
Prior service cost amortization	0	0
Actuarial loss amortization	0.4	0.6
Special termination benefits	0	0
Other	0	0
Net periodic benefit cost	$ 1.8	$ 2.1