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For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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Major Accounting Policies (Narratives) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Environmental expenditures	$ 28.3	$ 35.1	$ 37.1
Allowance for Doubtful Accounts	48.5	60.1
Provision for Doubtful Accounts	26.3	16.4	27.6
Capitalized interest	49.1	33.0	25.8
Asset retirement obligations	$ 109.4	$ 94.0	$ 89.8
Period For Reallocation Of Purchase Price	1 year
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Residual Value	$ 0.0
Computer Software [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	3 years
Computer Software [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Customer Relationships [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Customer Relationships [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	25 years
Patents and Technology [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years
Patents and Technology [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	20 years
Land Use Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	50 years