Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Additional Information (Details)

v3.7.0.1
Fair Value Measurements - Additional Information (Details)
$ / shares in Units, $ in Thousands
 6 Months Ended
Jun. 30, 2017
USD ($)
$ / shares
shares
Common stock warrants  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Number of shares underlying warrants | shares 40,000
Significant other observable inputs (Level 2)  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Estimated fair value of debt | $ $ 608
Significant unobservable inputs (Level 3) | Warrants on Preferred Stock  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Volatility rate 75.00%
Risk free interest rate 1.60%
Strike price (usd per share) $ 8.40
Fair value of common stock (usd per share) $ 0.57
Expected life 3 years 3 months 18 days
Significant unobservable inputs (Level 3) | Equity Unit Purchase Option  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Strike price (usd per share) $ 7.48
Fair value of common stock (usd per share) 0.57
Significant unobservable inputs (Level 3) | Equity Unit Purchase Option | Class A Warrant  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Strike price (usd per share) 5.23
Significant unobservable inputs (Level 3) | Equity Unit Purchase Option | Class B Warrant  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Strike price (usd per share) $ 4.49
Significant unobservable inputs (Level 3) | Minimum | Equity Unit Purchase Option  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Volatility rate 65.00%
Risk free interest rate 0.74%
Significant unobservable inputs (Level 3) | Maximum | Equity Unit Purchase Option  
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]  
Volatility rate 75.00%
Risk free interest rate 1.63%