Retirement Benefits (Benefit liability exceeds value of plan assets) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Sep. 30, 2015
U.S. [Member]
Pension Plans with PBO in Excess of Plan Assets:
PBO	$ 3,477.7	$ 2,917.1
Fair value of Plan assets	2,705.3	2,386.7
Pension Plans with ABO in Excess of Plan Assets:
ABO	3,242.5	2,689.2
Fair value of plan assets	2,705.3	2,386.7
International [Member]
Pension Plans with PBO in Excess of Plan Assets:
PBO	1,849.6	1,644.5
Fair value of Plan assets	1,411.1	1,299.1
Pension Plans with ABO in Excess of Plan Assets:
ABO	1,673.6	1,498.0
Fair value of plan assets	$ 1,370.1	$ 1,263.2

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- Definition

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=73719040&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=65897934&loc=d3e2417-114920

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- Definition

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.

+ References

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- References

No definition available.

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- Definition

If aggregate disclosures are presented, the aggregate benefit obligation for plans with 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 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920

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- Definition

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

+ References

+ Details

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