Supplementary Financial Statement Information (Details2) - Ashland Works Hot End [Member] $ in Millions	3 Months Ended
Mar. 31, 2016 USD ($)
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 22.1
Payments for Restructuring	(4.9)
Ending Balance	17.2
Costs for Temporarily Idled Operations	7.3
Minimum [Member]
Restructuring Reserve [Roll Forward]
Estimated Monthly Ongoing Costs	2.0
Maximum [Member]
Restructuring Reserve [Roll Forward]
Estimated Monthly Ongoing Costs	$ 3.0

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- Definition

An estimate of monthly ongoing cost

+ References

No definition available.

+ Details

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- Definition

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 5
-Section P
-Subsection 3, 4

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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