Stock Incentive Plan - Additional Information (Detail) (USD $)
12 Months Ended 1 Months Ended 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Aug. 31, 2013
Market-based Restricted Stock Units [Member]
Aug. 31, 2013
Market-based Restricted Stock Units [Member]
Minimum [Member]
Aug. 31, 2013
Market-based Restricted Stock Units [Member]
Maximum [Member]
Dec. 31, 2013
Stock Options [Member]
Dec. 31, 2013
Restricted Stock Units [Member]
Dec. 31, 2013
Restricted Stock Units [Member]
Service Based Restricted Stock Units [Member]
Dec. 31, 2013
Restricted Stock Units [Member]
Market-based Restricted Stock Units [Member]
Minimum [Member]
Dec. 31, 2013
Restricted Stock Units [Member]
Market-based Restricted Stock Units [Member]
Maximum [Member]
Dec. 31, 2013
Time Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]                        
Period of options vested             4 years   3 years 2 years 3 years  
Period of expiration             10 years          
Increase in shares available to grant 1,400,000                      
Shares available for grant 1,649,831                      
Cash received from stock option exercised $ 3,798,000 $ 2,682,000 $ 6,207,000                  
Requisite service period of compensation expense 4 years       2 years 3 years            
Fair value of common stock $ 33.55                      
Weighted average grant date fair value $ 11.60 $ 18.57 $ 22.42                  
Number of restricted stock units, granted       74,000       837,000       763,073
Total shareholder return target share, percentage         0.00% 200.00%            
Total shareholder return target share           148,000            
Unrecognized share-based compensation cost $ 36,656,000                      
Share-based compensation cost not yet recognized period for recognition 2 years