Quarterly report pursuant to Section 13 or 15(d)

Warrants (Details)

v3.20.2
Warrants (Details) - $ / shares
shares in Thousands
6 Months Ended
Jun. 30, 2020
Dec. 31, 2019
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 104.18  
Warrants outstanding (in shares) 279  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 279  
Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 115.54  
Warrants outstanding (in shares) 213  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 213  
Warrant Issued For | Derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 67.50  
Warrants outstanding (in shares) 66  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 66  
Financing | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 300.00  
Warrants outstanding (in shares) 8  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 8  
Financing | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 450.00  
Warrants outstanding (in shares) 9  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 9  
2017 Debt | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 27.60  
Warrants outstanding (in shares) 15  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 15  
2015 Offering | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 150.00  
Warrants outstanding (in shares) 115  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 115  
2019 Offering | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 7.43  
Warrants outstanding (in shares) 31  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 31  
2019 Offering | Warrant Issued With | Non-derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 7.59  
Warrants outstanding (in shares) 35  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 35  
2016 Offerings    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 67.50 $ 67.50
2016 Offerings | Warrant Issued For | Derivative warrants    
Class of Warrant or Right [Line Items]    
Warrants, exercise price (usd per share) $ 67.50  
Warrants outstanding (in shares) 66  
Warrants issued (in shares) 0  
Warrants expired (in shares) 0  
Warrants outstanding (in shares) 66