Share Capital - Stock Option Activity (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) $ / shares shares		Dec. 31, 2015 USD ($) $ / shares CAD / shares		Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) CAD / shares	Dec. 31, 2013 USD ($) $ / shares shares	Dec. 31, 2013 USD ($) CAD / shares	Dec. 31, 2015 CAD / shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Options Outstanding, Beginning balance	1,484,218				1,333,099		1,128,437
Number of Options, Granted	529,288				205,170		292,418
Number of Options, Exercised	(270,254)	[1]			(2,417)		(8,329)
Number of Options, Forfeited, cancelled or expired	(21,780)				(51,634)		(79,427)
Number of Options Outstanding, Ending balance	1,721,472				1,484,218		1,333,099
Number of Options Exercisable, Ending balance	1,034,576
Weighted Average Exercise Price Outstanding, Beginning balance | (per share)	$ 4.20		CAD 4.88		$ 3.88	CAD 3.98	$ 4.17	CAD 4.13
Weighted Average Exercise Price, Granted | (per share)	14.67		18.73		9.35	10.84	3.64	3.74
Weighted Average Exercise Price, Exercised | (per share)	3.65	[1]	4.66	[1]	5.23	6.07	5.88	6.07
Weighted Average Exercise Price, Forfeited, cancelled and expired | (per share)	8.78		11.21		5.14	5.96	4.76	4.90
Weighted Average Exercise Price Outstanding, Ending balance | (per share)	6.95		CAD 9.62		$ 4.20	CAD 4.88	$ 3.88	CAD 3.98
Weighted Average Exercise Price, Exercisable Ending balance | (per share)	$ 3.20		CAD 3.20						CAD 4.42
Aggregate Intrinsic Value, Exercised | $	$ 2,426	[1]			$ 23		$ 37
Aggregate Intrinsic Value, Outstanding, Ending balance | $	1,880		CAD 1,880		$ 15,551	CAD 15,551	$ 8,300	CAD 8,300
Aggregate Intrinsic Value, Exercisable, Ending balance | $	$ 5,010		CAD 5,010

[1] During the year ended December 31, 2015, 70,438 stock options were exercised for the same number of common shares in exchange for cash. In the same period, the Company issued 133,565 common shares for the cashless exercise of 199,816 stock options.