Annual report pursuant to Section 13 and 15(d)

Investment in Viking (Details Textual)

v3.6.0.2
Investment in Viking (Details Textual)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended 13 Months Ended
Apr. 13, 2016
USD ($)
shares
Apr. 30, 2016
USD ($)
$ / shares
shares
Jan. 31, 2016
USD ($)
May 31, 2015
USD ($)
$ / shares
shares
Apr. 30, 2015
May 31, 2014
USD ($)
program
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
May 31, 2015
$ / shares
Aug. 31, 2014
$ / shares
shares
Variable Interest Entity [Line Items]                      
Warrants to purchase number of shares (shares) | shares                     3,264,643
Exercise price per share of warrants (in USD per share) | $ / shares                     $ 125.08
Proceeds received from repayment of Viking note receivable             $ 300 $ 0 $ 0    
Note receivable from Viking             $ 3,207 $ 4,782      
Viking                      
Variable Interest Entity [Line Items]                      
Number of programs licensed | program           5          
Loss recorded (percent)                   100.00%  
Debt | Viking                      
Variable Interest Entity [Line Items]                      
Convertible loan facility extended           $ 2,500          
Repayment in equity (percent)         200.00%            
Common Stock                      
Variable Interest Entity [Line Items]                      
Aggregate value of shares received in Viking IPO       $ 29,200              
Shares of Viking stock purchased (shares) | shares       1,100,000              
Purchase of Viking common stock       $ 9,000              
Equity Method Investee                      
Variable Interest Entity [Line Items]                      
Shares sold in Viking IPO (shares) | shares   7,500,000                  
Initial offering price per share (in usd per share) | $ / shares   $ 1.25                  
Shares of Viking stock purchased (shares) | shares   560,000                  
Purchase of Viking common stock   $ 700                  
Interest rate on note due from Viking (percent)     2.50%         5.00%      
Extension of lock-up period     1 year                
Amount of loan to be repaid upon consummation of first capital financing transaction     $ 1,500                
Amount of loan to be repaid in cash upon consummation of first capital financing transaction     $ 300                
Warrants to purchase number of shares (shares) | shares   7,500,000                  
Exercise price per share of warrants (in USD per share) | $ / shares   $ 1.50                  
Warrants purchased (shares) | shares   560,000                  
Proceeds received from repayment of Viking note receivable $ 300                    
Shares received pursuant to MLA amendment (shares) | shares 960,000                    
Warrants received, licensing agreement (shares) | shares 960,000                    
Value of consideration received for repayment of convertible notes $ 1,200                    
Aggregate ownership, percent   32.70%         30.30%        
Decrease in equity method investment   $ (10,700)                  
Other than temporary impairment of investment in Viking             $ 7,400        
Equity Method Investee | IPO | Common Stock                      
Variable Interest Entity [Line Items]                      
Shares sold in Viking IPO (shares) | shares       3,700,000              
Aggregate offering price       $ 29,200              
Initial offering price per share (in usd per share) | $ / shares       $ 8.00           $ 8.00