v2.4.0.8
Stock-Based Compensation - Stock-Based Compensation Included in Unaudited Results of Operations (Detail) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock option/warrant expense, included in total operating expenses $ 21 $ 57
Officer compensation [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock option/warrant expense, included in total operating expenses 9 16
Non-employee directors [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock option/warrant expense, included in total operating expenses 5 5
Sales, general and administrative [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock option/warrant expense, included in total operating expenses 7 6
Research and development [Member]
    
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]    
Total stock option/warrant expense, included in total operating expenses    $ 30