Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Change in Level 3 (Details)

v3.19.2
Fair Value Measurements - Change in Level 3 (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Gain on revaluation of warrants issued in May 2019 financing and December 2015 financing $ 2,737 $ (213) $ 1,615 $ 520
Loss on modification of December 2015 warrants 0 $ 0 257 $ 0
Warrant Liability        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning Balance     585  
Initial fair value of warrants issued in conjunction with May 2019 financing     7,334  
Gain on revaluation of warrants issued in May 2019 financing and December 2015 financing     (1,615)  
Loss on modification of December 2015 warrants     257  
Loss on revaluation of contingent liabilities     0  
Ending Balance 6,561   6,561  
Contingent Success Fee Liability        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning Balance     34  
Initial fair value of warrants issued in conjunction with May 2019 financing     0  
Gain on revaluation of warrants issued in May 2019 financing and December 2015 financing     0  
Loss on modification of December 2015 warrants     0  
Loss on revaluation of contingent liabilities     1  
Ending Balance $ 35   $ 35