Capital Stock - Textual (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Equity [Abstract]
Stock options exercised (shares)	529,187	302,703
Weighted average exercise price of stock options exercised (usd per share)	$ 5.37	$ 6.14
Proceeds from exercises of stock options	$ 2,843	$ 1,858
Proceeds from issuance of common stock in connection with private placement	$ 50,000	$ 0

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- Definition

The cash inflow from the additional capital contribution to the entity.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

+ References

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

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