Other Expense (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Components of other expense
Net gain (loss) on dispositions of securities and property	$ (1.0)	$ 0.9	$ (5.5)
Interest income	7.8	6.0	5.0
Royalty income	2.3	3.6	2.4
Environmental charges	(9.3)	(4.5)	(5.9)
Other	(4.8)	(8.1)	(4.4)
Other expense	$ (5.0)	$ (2.1)	$ (8.4)

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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-Name Statement of Position (SOP)

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

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-Name Statement of Position (SOP)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef

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+ Details