Annual report pursuant to Section 13 and 15(d)

Capitalization and Equity Structure - Fair Values of Warrant Liability (Details)

v3.10.0.1
Capitalization and Equity Structure - Fair Values of Warrant Liability (Details)
 12 Months Ended
Dec. 31, 2018
year
$ / shares
Dec. 31, 2017
$ / shares
Dec. 31, 2016
$ / shares
Schedule of Capitalization, Equity [Line Items]      
Current share price (in dollars per share)     $ 8.00
Black-Scholes Option Pricing Model | Warrants for common stock      
Schedule of Capitalization, Equity [Line Items]      
Current share price (in dollars per share) $ 1.24 $ 2.13  
Conversion price (in dollars per share) $ 3.74 $ 3.74  
Risk-free interest rate | Black-Scholes Option Pricing Model | Warrants for common stock      
Schedule of Capitalization, Equity [Line Items]      
Measurement input 0.0248 0.0198  
Expected term (years) | Black-Scholes Option Pricing Model | Warrants for common stock      
Schedule of Capitalization, Equity [Line Items]      
Measurement input 1.99 2.99  
Volatility of stock | Black-Scholes Option Pricing Model | Warrants for common stock      
Schedule of Capitalization, Equity [Line Items]      
Measurement input 1.04 0.95