Business Segment Information (Reconciliation of Operating Income) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Business restructuring and cost reduction actions	$ (55.4)	$ 0	$ (87.8)	$ 0
Pension settlement loss	(12.6)	0	(12.6)	0
Gain on previously held equity interest	0	0	17.9	0
Operating Income	374.4us-gaap_OperatingIncomeLoss	384.7us-gaap_OperatingIncomeLoss	804.4us-gaap_OperatingIncomeLoss	770.3us-gaap_OperatingIncomeLoss
Segment Total [Member]
Segment Reporting Information [Line Items]
Operating Income	$ 442.4	$ 384.7	$ 886.9	$ 770.3

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan or reorganization actions. Excludes expenses related to a discontinued operation or an asset retirement obligation.

No definition available.

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Section 15

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(7)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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