Retirement Benefits (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3,213.3	2,572.9
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3,213.3	2,572.9	2,486.6
US Pension Benefit Plans [Member]
Net periodic benefit cost assumptions
Discount rate	5.20%	5.60%	6.20%
Expected return on plan assets	8.00%	8.00%	8.00%
Compensation increase rate	4.00%	4.00%	4.30%
Net benefit obligation assumptions
Discount rate	4.15%	5.20%
Compensation increase rate	4.00%	4.00%
Non US Pension Benefit Plans [Member]
Net periodic benefit cost assumptions
Discount rate	4.15%	4.14%	4.67%
Expected return on plan assets	5.93%	6.07%	6.18%
Compensation increase rate	3.03%	3.09%	2.88%
Net benefit obligation assumptions
Discount rate	3.37%	4.15%
Compensation increase rate	3.03%	3.03%
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
US Other Postretirement Benefit Plans [Member]
Net periodic benefit cost assumptions
Discount rate	4.90%	5.10%	6.00%
Net benefit obligation assumptions
Discount rate	3.85%	4.90%
Healthcare cost trend rate	8.00%	8.50%
Non-U.S. Other Postretirement Benefit Plans [Member]
Net periodic benefit cost assumptions
Discount rate	4.10%	4.75%	5.00%
Net benefit obligation assumptions
Discount rate	3.80%	4.10%
Healthcare cost trend rate	6.68%	7.12%
Cash [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.4	0.4
Cash [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	26.8	32.2
Common Stock [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	653.7	504.0
Common Stock [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	39.3	31.5
Equity Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	530.5	317.5
Equity Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	296.9	257.8
Corporate Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	525.9	347.6
Corporate Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	68.7	52.1
Foreign Government Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.8	1.9
Fixed Income Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	145.5	237.5
Fixed Income Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	167.1	161.0
Insurance Contracts [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.8	0.9
Insurance Contracts [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	38.5	26.9
US Government Agencies Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	368.4	268.9
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,168.9	960.5
Fair Value, Inputs, Level 1 [Member] | Cash [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.4	0.4
Fair Value, Inputs, Level 1 [Member] | Cash [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	26.8	32.2
Fair Value, Inputs, Level 1 [Member] | Common Stock [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	653.7	504.0
Fair Value, Inputs, Level 1 [Member] | Common Stock [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	39.3	31.5
Fair Value, Inputs, Level 1 [Member] | Equity Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Equity Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Corporate Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Foreign Government Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.8	1.9
Fair Value, Inputs, Level 1 [Member] | Fixed Income Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Fixed Income Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Insurance Contracts [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | Insurance Contracts [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	287.9	246.3
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	1,864.1	1,442.6
Fair Value, Inputs, Level 2 [Member] | Cash [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Cash [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Common Stock [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Common Stock [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Equity Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	530.5	317.5
Fair Value, Inputs, Level 2 [Member] | Equity Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	296.9	257.8
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	525.9	347.6
Fair Value, Inputs, Level 2 [Member] | Corporate Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	68.7	52.1
Fair Value, Inputs, Level 2 [Member] | Foreign Government Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Fixed Income Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	145.5	237.5
Fair Value, Inputs, Level 2 [Member] | Fixed Income Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	167.1	161.0
Fair Value, Inputs, Level 2 [Member] | Insurance Contracts [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | Insurance Contracts [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	80.5	22.6
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	180.3	169.8	149.2
Fair Value, Inputs, Level 3 [Member] | Cash [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Cash [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Common Stock [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Common Stock [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Equity Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Equity Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Corporate Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Foreign Government Debt Securities [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Fixed Income Common Collective Trust [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Fixed Income Common Collective Trust [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets
Fair Value, Inputs, Level 3 [Member] | Insurance Contracts [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0.8	0.9	0.9
Fair Value, Inputs, Level 3 [Member] | Insurance Contracts [Member] | Non US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	38.5	26.9	28.5
Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member] | US Pension Benefit Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets