v2.4.0.6
Share Based Compensation - Additional Information (Detail) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended 9 Months Ended 9 Months Ended
Sep. 30, 2012
Sep. 30, 2011
Sep. 30, 2012
Sep. 30, 2011
Dec. 31, 2010
Omnibus Incentive Plan
Sep. 30, 2012
Stock Options
Sep. 30, 2012
Restricted Stock Units (RSUs)
Minimum
Sep. 30, 2012
Restricted Stock Units (RSUs)
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                
Number of shares authorized for stock award, maximum         6,045,511      
Common stock remained available for grants 5,000,000   5,000,000          
Stock options, expiration term     10 years          
Share based award, vesting period           4 years 2 years 4 years
Exercise period of vested option after employment relationship end 3 months   3 months          
Weighted average grant date fair value of options granted     $ 8.51 $ 6.10        
Share based compensation expense $ 2,208 $ 906 $ 4,954 $ 4,182        
Total unrecognized compensation cost related to non-vested share-based compensation arrangements $ 22,861   $ 22,861