Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Summary of changes in fair value of the Company's warrant liability measured at fair value using significant unobservable inputs (Level 3) (Details)

v3.19.2
Fair Value Measurements - Summary of changes in fair value of the Company's warrant liability measured at fair value using significant unobservable inputs (Level 3) (Details) - Warrant [Member] - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Beginning balance $ 103 $ 927 $ 210 $ 1,228
Additions 0 65 4 65
Change in fair value (64) 4,358 (175) 4,249
Reclass to additional paid-in capital 0     (192)
Ending balance $ 39 $ 5,350 $ 39 $ 5,350