Consolidated Balance Sheets (Parenthetical) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Common stock    
Common shares par value (in usd per share) $ 0.00005 $ 0.00005
Common shares authorized 500,000,000 22,000,000
Common shares issued 26,243,950 4,217,419
Common shares outstanding 26,243,950 4,217,419
Convertible Series A Preferred Stock    
Convertible preferred stock:    
Par value (in usd per share)   $ 0.00005
Convertible preferred stock shares authorized 0 2,486,507
Convertible preferred stock shares issued 0 2,383,745
Convertible preferred stock shares outstanding 0 2,383,745
Liquidation preference   $ 1,387
Convertible Series B Preferred Stock    
Convertible preferred stock:    
Par value (in usd per share)   $ 0.00005
Convertible preferred stock shares authorized 0 3,649,368
Convertible preferred stock shares issued 0 3,649,368
Convertible preferred stock shares outstanding 0 3,649,368
Liquidation preference   $ 3,089
Convertible Series C Preferred Stock    
Convertible preferred stock:    
Par value (in usd per share)   $ 0.00005
Convertible preferred stock shares authorized 0 5,406,501
Convertible preferred stock shares issued 0 5,406,501
Convertible preferred stock shares outstanding 0 5,406,501
Liquidation preference   $ 8,000
Convertible Series D Preferred Stock    
Convertible preferred stock:    
Par value (in usd per share)   $ 0.00005
Convertible preferred stock shares authorized 0 3,409,250
Convertible preferred stock shares issued 0 3,409,210
Convertible preferred stock shares outstanding 0 3,409,210
Liquidation preference   $ 13,000