Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies (Details)

v3.10.0.1
Summary of Significant Accounting Policies (Details) - Fair Value, Measurements, Recurring [Member] - USD ($)
$ in Thousands
Jun. 30, 2018
Dec. 31, 2017
Assets    
Short-term investments $ 9,874  
Total 9,874  
Liabilities    
Contingent royalty obligation 1,821 $ 1,662
Total 1,821 1,662
Level 1 [Member]    
Assets    
Short-term investments 4,868  
Total 4,868  
Liabilities    
Contingent royalty obligation
Total
Level 2 [Member]    
Assets    
Short-term investments 5,006  
Total 5,006  
Liabilities    
Contingent royalty obligation
Total
Level 3 [Member]    
Assets    
Short-term investments  
Total  
Liabilities    
Contingent royalty obligation 1,821 1,662
Total $ 1,821 $ 1,662