Share Capital - Additional Information (Details)	9 Months Ended
Sep. 30, 2018 $ / shares shares
Share Capital [Line Items]
The Number of ordinary shares that originally could be purchased by exercise of warrants	504,225
Warrants exercise price \| $ / shares	$ 3.59
Options exercised	2,486,026
Ordinary shares issued upon option exercise	2,484,048
Warrant
Share Capital [Line Items]
The Number of ordinary shares that originally could be purchased by exercise of warrants in cash	3,879
Warrant \| Warrants Not Settleable in Cash
Share Capital [Line Items]
Number of shares issued upon the exercise of warrants	437,081

Class of warrant number of securities called by warrants exercised for cash.

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- Definition

Ordinary shares issued upon option exercise.

+ References

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Share capital.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Number of new stock issued during the period.

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Number of share options (or share units) exercised during the current period.

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