Retirement Benefits (Details 5) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Investments measured at fair value
Defined benefit plan fair value of plan assets	$ 3,591.0	$ 3,367.0
Fair Value, Inputs, Level 1 [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	1,213.8	1,217.1
Fair Value, Inputs, Level 2 [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	2,177.9	1,968.6
Fair Value, Inputs, Level 3 [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	199.3	181.3	180.3
Cash and Cash Equivalents [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	1.9	3.7
Cash and Cash Equivalents [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	7.2	19.0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	1.9	3.7
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	7.2	19.0
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Common stock [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	706.8	711.8
Common stock [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	46.4	41.6
Common stock [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	706.8	711.8
Common stock [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	46.4	41.6
Common stock [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Common stock [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Common stock [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Common stock [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Mutual funds [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	216.8	196.3
Mutual funds [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	216.8	196.3
Mutual funds [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Mutual funds [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Equity Common collective trusts [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	527.2	561.5
Equity Common collective trusts [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	286.0	286.4
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	527.2	561.5
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	286.0	286.4
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Equity Common collective trusts [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Corporate debt [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	692.6	535.7
Corporate debt [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	31.0	39.9
Corporate debt [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Corporate debt [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Corporate debt [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	692.6	535.7
Corporate debt [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	31.0	39.9
Corporate debt [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Corporate debt [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
U.S. Government Securities [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	378.6	357.0
U.S. Government Securities [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	231.4	240.8
U.S. Government Securities [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	147.2	116.2
U.S. Government Securities [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Non-U.S. Government securities [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	18.2	17.6
Non-U.S. Government securities [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	3.3	3.9
Non-U.S. Government securities [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	14.9	13.7
Non-U.S. Government securities [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Fixed income securities Common collective trusts [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	129.4	128.6
Fixed income securities Common collective trusts [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	266.7	239.0
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	129.4	128.6
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	266.7	239.0
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Fixed income securities Common collective trusts [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Private equity [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	78.8	80.4
Private equity [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Private equity [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Private equity [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	78.8	80.4	83.2
Alternative equity [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	49.9	42.1
Alternative equity [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Alternative equity [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Alternative equity [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	49.9	42.1	53.4
Real estate [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	88.9	52.9
Real estate [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Real estate [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	80.3	44.6
Real estate [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	8.6	8.3	0
Insurance contracts [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	0.9	0.8
Insurance contracts [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	57.8	45.5
Insurance contracts [Member] | Fair Value, Inputs, Level 1 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Insurance contracts [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Insurance contracts [Member] | Fair Value, Inputs, Level 2 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Insurance contracts [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Insurance contracts [Member] | Fair Value, Inputs, Level 3 [Member] | U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	0.9	0.8	0.8
Insurance contracts [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	57.8	45.5	38.5
Other [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	5.9	7.2
Other [Member] | Fair Value, Inputs, Level 1 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets
Other [Member] | Fair Value, Inputs, Level 2 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	2.6	3.0
Other [Member] | Fair Value, Inputs, Level 3 [Member] | Non-U.S. Pension Benefit Plans [Member]
Investments measured at fair value
Defined benefit plan fair value of plan assets	$ 3.3	$ 4.2	$ 4.4