Concentration of Credit Risk and Off-Balance Sheet Risk - Additional Information (Detail)	3 Months Ended	9 Months Ended
Sep. 30, 2013 Customer	Sep. 30, 2012 Customer	Sep. 30, 2013 Customer Institution	Sep. 30, 2012 Customer
Risks And Uncertainties [Abstract]
Number of institution the Company places its cash with			1
Minimum percentage of revenue and trade receivable accounted for major customers	10.00%	10.00%	10.00%	10.00%
Number of energy consumption more than 10%	0	0	0	0
Minimum limit of energy consumption			10.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

-Publisher FASB

-Name Accounting Standards Codification

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

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-Name Accounting Standards Codification

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

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-Name Accounting Standards Codification

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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