Subsequent Event (Details) $ / shares in Units, $ in Millions	Feb. 11, 2016 USD ($) item $ / shares shares	Jan. 19, 2016 item $ / shares shares	Oct. 27, 2015 item $ / shares	Feb. 10, 2016 $ / shares shares	Jan. 18, 2016 $ / shares shares
Convertible loan | Sentient Loan
Subsequent Events
Stock price trigger (in dollars per share) | $ / shares			$ 0.29
Consecutive trading days, period | item			15
Subsequent Event | 2012 Warrants
Subsequent Events
Number of common shares that can be purchased upon exercise of warrant | shares	5,677,757	5,084,193		5,084,193	4,031,409
Increase in number of shares to be issued for exercise of warrants | shares	593,564	1,052,784
Exercise price of warrants (in dollars per share) | $ / shares	$ 5.09	$ 5.68		$ 5.68	$ 7.17
Subsequent Event | 2014 Warrants
Subsequent Events
Number of common shares that can be purchased upon exercise of warrant | shares	5,365,983	5,108,347		5,108,347	4,746,000
Increase in number of shares to be issued for exercise of warrants | shares	257,636	362,347
Exercise price of warrants (in dollars per share) | $ / shares	$ 0.91	$ 1.01		$ 1.01	$ 1.21
Subsequent Event | Convertible loan | Sentient Loan
Subsequent Events
Amount of debt converted to equity | $	$ 3.9
Amount of accrued interest converted to equity | $	$ 0.1
Equity shares issued upon conversion of debt | shares	23,335,000
Exercise price per share of shares converted from debt | $ / shares	$ 0.172
Stock price trigger (in dollars per share) | $ / shares		$ 0.29
Stock price trigger (as a percent)	90.00%	90.00%
Consecutive trading days, period | item	15	15
Debt outstanding | $	$ 1.1
Amount payable on failing to convert debt and accrued interest | $	$ 1.2