Warrants (Details)	3 Months Ended	6 Months Ended
	Jun. 30, 2015 $ / shares shares	Jun. 30, 2015 $ / shares shares	Nov. 21, 2012 CAD / shares	Apr. 04, 2011 CAD / shares
Class of Warrant or Right [Line Items]
Number of warrants outstanding	2,273,143	2,273,143
April 4, 2011 Warrants
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share) | (per share)	$ 6.74	$ 6.74		CAD 7.46
Number of warrants outstanding	1,288,107	1,288,107
November 21, 2012 Warrants
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share) | (per share)	$ 7.86	$ 7.86	CAD 8.70
Number of warrants outstanding	985,036	985,036
Warrants exercised	179,296	192,570
Shares of common stock issued	139,503	148,818