Costs associated with discontinuance of planned integration of product.

No definition available.

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Namespace Prefix:	kop_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228

Reference 2: 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Gain (loss) from sale or disposal of an organization or integrated set of activities (for example, but not limited to, a partnership or corporation) engaged in providing a product or service in a commercial, industrial, or professional environment.

+ References

No definition available.

+ Details

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- Details

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- Details

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Segment Information - Summary of Results of Segment Operations (Parenthetical) (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Jan. 16, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenue from External Customer [Line Items]
Gain on sale of business		$ 0.0	$ 0.0	$ 3.2	$ 0.0
Impairment charges				2.7	4.7
Netherlands [Member]
Revenue from External Customer [Line Items]
Plant closure cost					10.8
China [Member]
Revenue from External Customer [Line Items]
Impairment charges					$ 4.7
United States [Member]
Revenue from External Customer [Line Items]
Impairment charges				2.5
North American Utility Pole Business [Member]
Revenue from External Customer [Line Items]
Gain on sale of business	$ 3.2
North American Utility Pole Business [Member] \| Wood Treating Facility [Member] \| United States [Member]
Revenue from External Customer [Line Items]
Gain on sale of business				3.2
Impairment charges				$ 2.5