Quarterly report pursuant to Section 13 or 15(d)

Derivative Financial Instruments - Changes in Outstanding Warrants (Details)

v3.10.0.1
Derivative Financial Instruments - Changes in Outstanding Warrants (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Sep. 30, 2017
Sep. 30, 2018
Sep. 30, 2017
Changes in derivative instrument liability            
Balance at the beginning of the period     $ 17,582   $ 17,582  
Change in fair value of warrants $ 433     $ (55) (7,815) $ (216)
Balance at the end of the period $ 9,767       $ 9,767  
Derivative instrument liability            
Change in warrants            
Balance of warrants outstanding, beginning of period (in shares)     21,915,426   21,915,426  
Expiration of warrants (in shares)     (210,000)      
Balance of warrants outstanding, end of period (in shares) 21,705,426       21,705,426  
Changes in derivative instrument liability            
Balance at the beginning of the period     $ 17,582   $ 17,582  
Change in fair value of warrants $ 433 $ (2,604) $ (5,644)      
Balance at the end of the period $ 9,767       $ 9,767