Capital Stock - Textual (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	6 Months Ended
	Apr. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Equity [Abstract]
Stock options exercised (shares)		55,780	323,981
Weighted average exercise price of stock options exercised (usd per share)		$ 2.55	$ 2.58
Proceeds from exercises of stock options		$ 142	$ 837
Shares issued (shares)	6,300,000
Common stock, par value (usd per share)	$ 0.0001	$ 0.0001		$ 0.0001
Share price (usd per share)	$ 4.00
Net proceeds from public offering	$ 23,300
Underwriting discounts, commissions and other offering expenses	$ 500