Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Warrants - Summary of Derivative Warrant Activity (Details)

v3.19.3
Fair Value of Warrants - Summary of Derivative Warrant Activity (Details)
$ in Thousands
9 Months Ended
Sep. 30, 2019
USD ($)
Class of Warrants Outstanding [Roll Forward]  
Fair value of warrants outstanding as of December 31, 2018 $ 248
Change in fair value of warrants (233)
Fair value of warrants outstanding as of September 30, 2019 15
2016 Offerings  
Class of Warrants Outstanding [Roll Forward]  
Fair value of warrants outstanding as of December 31, 2018 225
Change in fair value of warrants (210)
Fair value of warrants outstanding as of September 30, 2019 15
2017 Offering  
Class of Warrants Outstanding [Roll Forward]  
Fair value of warrants outstanding as of December 31, 2018 23
Change in fair value of warrants (23)
Fair value of warrants outstanding as of September 30, 2019 $ 0