Annual report pursuant to Section 13 and 15(d)

Employee Compensation Plans - Additional Information (Detail)

v2.4.0.6
Employee Compensation Plans - Additional Information (Detail) (USD $)
 12 Months Ended
Dec. 31, 2012
Y
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2008
Employee Incentive Compensation Program [Line Items]        
Percentage of compensation employees could elect to contribute prior to 2009 maximum       17.00%
Percentage of compensation employees could elect to contribute prior to 2009 minimum       2.00%
Maximum percentage of contribution by employer into compensation plan prior to 2009       3.00%
Percentage of employee may elect to contribute limited to maximum annual amount 75.00%      
Percentage of deferred earnings for which the company matches contribution one dollar for each dollar 1.00%      
Percentage of matching contribution for each dollar of deferred earnings above 1% for additional subsequent earnings of 5% 50.00%      
Percentage of subsequent deferred earnings 5.00%      
Fully vested contribution period 2      
Contribution made by company to its profit sharing plan $ 2,700,000 $ 2,500,000 $ 2,300,000  
Percentage of base annual salary deferred by employees 75.00%      
Percentage of annual bonus deferred by employees 100.00%      
Increased percentage of matching contribution to align with retirement plan match 3.50% 3.50% 3.50%  
Deferred compensation plans expense excluding participant contributions 2,900,000 200,000 2,100,000  
Total long term deferred compensation liability 29,454,000 23,702,000    
Value of the assets in the rabbi trust 24,267,000 20,511,000    
Expenses relating to international deferred compensation plans $ 7,200,000 $ 4,900,000 $ 3,400,000