Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
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Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 20
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-Paragraph 1
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- Definition

Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 12
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Topic 230
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Estimated time frame for resolution of the uncertainty as to the loss for an individual site.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Commitments and Contingencies (Piedmont) (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2008
Loss Contingencies [Line Items]
Pretax environmental expense	$ 12.2	$ 11.8	$ 19.8
Piedmont, Florida [Member]
Loss Contingencies [Line Items]
Accrual for Environmental Loss Contingencies	$ 17.5			$ 24.0
Years to complete environmental remediation	until 2019 to complete source area remediation with groundwater recovery and treatment, continuing through 2029.
Change in estimated exposure	$ 0.0
Total anticipated exposure at this site				24.0
Segment Discontinued Operation Member \| Piedmont, Florida [Member]
Loss Contingencies [Line Items]
Pretax environmental expense				$ 24.0