Quarterly report pursuant to Section 13 or 15(d)

Capitalization and Equity Structure - Warrants (Details)

v3.10.0.1
Capitalization and Equity Structure - Warrants (Details) - $ / shares
 1 Months Ended 9 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2018
Dec. 31, 2017
Dec. 31, 2016
Sep. 30, 2017
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   3,396,000      
Issued (in shares)   0      
Expired (in shares)   0      
Ending balance (in shares)   3,396,000 3,396,000    
Information Agent Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)   $ 1.5     $ 1.5
Term (Years)   3 years      
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   200,000      
Issued (in shares)   0      
Expired (in shares)   0      
Ending balance (in shares)   200,000 200,000    
2015 Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share) $ 3.74 $ 3.74      
Term (Years)   5 years      
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   1,604,000      
Issued (in shares) 2,122,000 0      
Expired (in shares)   0      
Ending balance (in shares)   1,604,000 1,604,000    
Placement agent warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)   $ 7      
Term (Years)   5 years      
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   426,000      
Issued (in shares)   0      
Expired (in shares)   0      
Ending balance (in shares)   426,000 426,000    
PPO warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)   $ 14      
Term (Years)   5 years      
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   1,078,000      
Issued (in shares)   0      
Expired (in shares)   0      
Ending balance (in shares)   1,078,000 1,078,000    
Pre-2014 warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)   $ 9.66      
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)   88,000      
Issued (in shares)   0      
Expired (in shares)   0      
Ending balance (in shares)   88,000 88,000    
Pre-2014 warrants | Minimum          
Schedule of Capitalization, Equity [Line Items]          
Term (Years)   9 years      
Pre-2014 warrants | Maximum          
Schedule of Capitalization, Equity [Line Items]          
Term (Years)   10 years      
Warrant          
Schedule of Capitalization, Equity [Line Items]          
Warrants exercised (in shares)     30 488