Retirement Benefits (Details 7) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Pension Benefits [Member]
Estimated future benefit payments
2013	$ 214.7
2014	210.6
2015	215.6
2016	219.4
2017	226.5
2018-2022	1,275.1
Other Postretirement Benefits [Member]
Estimated future benefit payments
2013	16.1
2014	15.2
2015	14.5
2016	13.6
2017	12.7
2018-2022	$ 54.2

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ 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 (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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