Commitments and Contingencies (Pasadena) (Narrative) (Details) (Pasadena Texas Member [Member], USD $) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
Mar. 31, 2015	Sep. 30, 2012
Pasadena Texas Member [Member]
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies	$ 12.0
Estimated environmental remediation completion year	2042
Total anticipated exposure at this site		13
Change in estimated exposure	$ 0

No authoritative reference available.

No definition available.

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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 25

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6395460&loc=d3e13647-108346

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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.

+ References

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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

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q4)

-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section Y

-Paragraph Question 4

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