Quarterly report pursuant to Section 13 or 15(d)

Basis of presentation, principles of consolidation and significant accounting policies - Fair Value of Warrant Liability (Details)

v3.19.2
Basis of presentation, principles of consolidation and significant accounting policies - Fair Value of Warrant Liability (Details) - Recurring - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis    
Fair value of derivative liability $ 6,944 $ 1,508
Quoted Pricesin ActiveMarkets forIdenticalAssets (Level 1)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis    
Fair value of derivative liability 0 0
Significant OtherObservable Inputs(Level 2)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis    
Fair value of derivative liability 0 0
Significant OtherUnobservable Inputs(Level 3)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis    
Fair value of derivative liability $ 6,944 $ 1,508