Share Capital - Summary of Non-Vested Stock Option Activity (Details)	12 Months Ended
	Dec. 31, 2018 $ / shares shares	Dec. 31, 2018 $ / shares shares	Dec. 31, 2017 $ / shares shares	Dec. 31, 2017 $ / shares shares
Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares Roll Forward
Number of Options, Non-vested, Beginning balance	900,604	900,604
Number of Options, Granted	706,600	706,600	620,950	620,950
Number of Options, Vested	(437,771)	(437,771)
Number of Options, Forfeited or cancelled	(63,962)	(63,962)
Number of Options, Non-vested, Ending balance	1,105,471	1,105,471	900,604	900,604
Weighted Average Grant Date Fair Value, Non-vested, Beginning balance | (per share)	$ 5.66	$ 7.12
Weighted Average Grant Date Fair Value, Granted | (per share)	3.74	4.84	$ 5.02
Weighted Average Grant Date Fair Value, Vested | (per share)	6.54	8.47
Weighted Average Grant Date Fair Value, Forfeited or cancelled | (per share)	5.17	6.70
Weighted Average Grant Date Fair Value, Non-vested, Ending balance | (per share)	$ 4.11	$ 5.61	$ 5.66	$ 7.12