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Summary of significant accounting policies - Concentration of Credit Risk (Details) (Customer concentration risk)
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12 Months Ended | |
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Dec. 31, 2013
customer
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Dec. 31, 2012
customer
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Revenues
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| Concentration Risk [Line Items] | ||
| Number of customer representing more than 10% of revenues or trade accounts receivable | 0 | 1 |
| Concentration risk, percentage | 10.00% | |
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Trade accounts receivable
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| Concentration Risk [Line Items] | ||
| Number of customer representing more than 10% of revenues or trade accounts receivable | 1 | 1 |
| Concentration risk, percentage | 21.60% | 16.00% |
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- Definition
Concentration Risk, Number of Significant Customers No definition available.
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- Details
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- Definition
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
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