Retirement Benefits (Details 8) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012
One percentage point change in assumed health care cost trend rates
One-Percentage Point Increase - Increase to total of service and interest cost components	$ 0.2	$ 0.2
One-Percentage Point Decrease - Decrease to total of service and interest cost components	(0.2)	(0.2)
One-Percentage Point Increase - Increase to postretirement benefit obligation	2.1	2.4
One-Percentage Point Decrease - Decrease to postretirement benefit obligation	(1.8)	(2.1)
Pension plans with accumulated benefit obligations in excess of plan assets
Projected benefit obligation	760.1	3,850.4
Accumulated benefit obligation	674.6	3,573.5
Fair value of plan assets	$ 436.1	$ 2,919.0

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (m)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

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Amount of effect of a one-percentage-point decrease in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

+ References

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the accumulated postretirement benefit obligation for health care benefits.

+ References

+ Details

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The effect of a one-percentage-point increase in the assumed health care cost trend rates on the aggregate of the service and interest cost components of net periodic postretirement health care benefit costs.

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If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=32704760&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920

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If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

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If aggregate disclosures are presented, the aggregate projected benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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