Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation and Employee Benefit Plans - Fair Value of Stock Options (Detail)

v2.4.0.6
Stock-Based Compensation and Employee Benefit Plans - Fair Value of Stock Options (Detail) (Stock options [Member], USD $)
9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Stock options [Member]
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Weighted-average grant date fair value per share $ 2.37 $ 4.26
Risk-free interest rate 0.88% 2.01%
Dividend yield      
Expected life (years) 4 years 10 months 2 days 5 years 18 days
Volatility 55.91% 51.83%