Stock-based compensation - Valuation Assumptions (Details) |
6 Months Ended |
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Jun. 30, 2017
$ / shares
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |
| Expected volatility | 37.00% |
| Risk-free rate of return | 1.86% |
| Expected life (in years) | 6 years 6 months |
| Dividend yield | 0.00% |
| Weighted-average fair value (in dollars per share) | $ 2.13 |
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- References No definition available.
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The estimated measure of the percentage amount by which a share price is expected to fluctuate during the expected term of a nonvested share or option award issued to other than an employee. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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