Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation (Details 3)

v2.4.0.8
Stock-based Compensation (Details 3) (Employee Stock Purchase Plan, USD $)
3 Months Ended
Mar. 31, 2014
item
Mar. 31, 2013
Employee Stock Purchase Plan
   
Weighted-average assumptions relating to options granted    
Risk-free interest rate (as a percent) 0.30% 0.20%
Expected term (in years) 1 year 8 months 12 days 1 year 4 months 24 days
Dividend yield (as a percent) 0.00% 0.00%
Expected volatility (as a percent) 66.00% 58.00%
Additional disclosures    
Award offering period 24 months  
Number of purchase periods per award offering period 4  
Award purchase period 6 months  
Purchase price expressed as a percentage of fair market value of common stock on the first day of the offering period 85.00%  
Purchase price of common shares as a percentage of the fair market value on the purchase date 85.00%  
Total incremental fair value for the Purchase Plan reset $ 577,000  
Total number of shares of common stock reserved for future issuance 84,030