Commitments and Contingencies (Pasadena) (Narrative) (Details) - Pasadena Texas Member [Member] - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2015	Sep. 30, 2012
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies	$ 11.5
Years to complete environmental remediation	until 2042
Total anticipated exposure at this site		$ 13.0
Change in estimated exposure	$ 0.0

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

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-Name Accounting Standards Codification

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- Definition

The Increase or Decrease in the accrual for environmental loss in the period from revisions in estimates to existing obligations. The amount does not relate to changes in the environmental accrual related to business acquisitions or divestitures, or to currency movements.

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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

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-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q4)

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

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-Name Staff Accounting Bulletin (SAB)

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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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