Share-based Compensation - Summary of Stock Option Activities (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Number of Stock Options
Number of Options, Options outstanding, beginning of period	161,278	152,584
Number of Options, Granted	487,700	21,492
Number of Options, Forfeited and cancelled	(19,349)	(12,798)
Number of Options, Options outstanding, end of period	629,629	161,278
Number of Options, Options exercisable, end of period	181,518
Number of Options, Options vested and expected to vest	628,928
Stock Options, Weighted Average Exercise Price
Weighted Average Exercise Price, Options outstanding, beginning of period	$ 18.30	$ 20.20
Weighted Average Exercise Price, Granted	3.22	4.92
Weighted Average Exercise Price, Forfeited and cancelled	28.70	18.45
Weighted Average Exercise Price, Options outstanding, end of period	6.30	$ 18.30
Weighted Average Exercise Price, Options exercisable, end of period	13.19
Weighted Average Exercise Price, Options vested and expected to vest, end of period	$ 6.30
Stock Options, Weighted Average Remaining Contractual Term
Weighted Average Remaining Contractual Term (in years), Options outstanding	8 years 10 months 10 days	6 years 11 months 19 days
Weighted Average Remaining Contractual Term (in years), Options exercisable	7 years 5 months 16 days
Weighted Average Remaining Contractual Term (in years), Options vested and expected to vest	8 years 10 months 10 days
Share Options, Aggregate Intrinsic Value
Aggregate intrinsic value, Options Outstanding, end of period	$ 25
Aggregate intrinsic value, Options vested and expected to vest, end of period	$ 25