Quarterly report pursuant to Section 13 or 15(d)

Stock Option Plans (Details)

v3.4.0.3
Stock Option Plans (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Stock-based compensation expense $ 161 $ 488
Research and development [Member]    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Stock-based compensation expense 39 184
General and administrative [Member]    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Stock-based compensation expense $ 122 $ 304