Related Party Transactions - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Related Party Transaction [Line Items]
Loan to related party	$ 9,500,000	$ 9,500,000
Tangshan Koppers Kailuan Carbon Chemical Company Limited [Member]
Related Party Transaction [Line Items]
Loan to related party	$ 9,500,000
Ownership percentage	30.00%
Loan repayable date	2015-11
Loan repayable beginning date	2015-06
Provision for loans	$ 0
Tangshan Koppers Kailuan Carbon Chemical Company Limited [Member] \| Loan [Member]
Related Party Transaction [Line Items]
Installment payment defaulted	$ 1,600,000

Loan repayable date.

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- Definition

Loan repayable installments beginning period.

+ References

No definition available.

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- Definition

Amount of outstanding long-term debt or borrowing associated with any securities or credit agreement for which there has been a default in principal, interest, sinking fund, or redemption provisions, or any breach of covenant that existed at the end of the period and subsequently has not been cured.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

+ References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

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- 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.

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