Annual report pursuant to Section 13 and 15(d)

Income Taxes (Details Textual)

v3.8.0.1
Income Taxes (Details Textual) - USD ($)
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount   $ 17,220    
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount   $ 4,153 $ 10,827,000  
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent   34.00% 34.00% 34.00%
Scenario, Plan [Member]        
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent 21.00%      
Federal        
Operating Loss Carryforwards   $ 120,366,000    
Operating Loss Carryforwards, Expiration Date     Dec. 31, 2027  
Federal | Employee Stock Option [Member]        
Deferred Tax Assets, Net of Valuation Allowance, Total   1,749,000    
Federal | Research Tax Credit Carryforward [Member]        
Operating Loss Carryforwards   1,294,000    
State        
Operating Loss Carryforwards   84,466,000    
Operating Loss Carryforwards, Expiration Date     Dec. 31, 2017  
State | Employee Stock Option [Member]        
Deferred Tax Assets, Net of Valuation Allowance, Total   689,000    
Open Tax Year     2007  
State | Research Tax Credit Carryforward [Member]        
Operating Loss Carryforwards   655,000    
Foreign Tax Authority [Member]        
Operating Loss Carryforwards   $ 4,701,000