Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Details 2)

v2.4.0.8
Stock-Based Compensation (Details 2) (USD $)
9 Months Ended
Sep. 30, 2013
Sep. 30, 2012
Summary of weighted average assumptions used to value options granted    
Grant date fair value of options (in dollars per share) $ 6.11 $ 4.96
Volatility (as a percent) 40.40% 39.60%
Risk-free interest rate (as a percent) 1.00% 1.20%
Dividend yield (as a percent) 0.00% 0.00%
Expected term 6 years 6 years