Annual report pursuant to Section 13 and 15(d)

Employee Compensation Plans (Details)

v2.4.0.6
Employee Compensation Plans (Details) (USD $)
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2008
Employee compensation plans (Textual) [Abstract]        
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 employees 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 earning 5.00%      
Contribution made by company to its profit sharing plan $ 2,500,000 $ 2,300,000 $ 2,200,000  
Percentage of base annual salary deferred by employees 75.00%      
Percentage of annual bonus deferred by employees 100.00%      
Percentage of matching contribution     3.00%  
Increased percentage of matching contribution to align with retirement plan match 3.50% 3.50%    
Deferred compensation plan expense net of participant contributions 200,000 2,100,000 2,600,000  
Total long term deferred compensation liability 23,702,000 20,167,000    
Value of the assets in the rabbi trust $ 20,511,000 $ 18,536,000