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Deferred Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Share Based Payments Disclosure [Line Items]      
Description of vesting term for awards granted Awards granted under the plan are generally amortized ratably over a three to five-year service period following the date of the grant.    
Deferred compensation payable $ 12.3 $ 10.0  
Unrecognized deferred cash compensation (prior to the consideration of forfeitures) $ 11.4    
Deferred compensation arrangement with individual, maximum contractual term 1 year 6 months    
Compensation expense from deferred compensation $ 10.3 7.2 $ 8.9
Minimum      
Share Based Payments Disclosure [Line Items]      
Service period for deferred compensation payable 3 years    
Maximum      
Share Based Payments Disclosure [Line Items]      
Service period for deferred compensation payable 5 years    
Restricted stock units      
Share Based Payments Disclosure [Line Items]      
Compensation expense from the vesting of restricted stock units $ 31.1 $ 31.8 $ 45.8
Weighted average grant date fair value for restricted stock units granted (in usd per share) $ 13.26 $ 8.82 $ 22.55
Unrecognized restricted stock units compensation expense $ 38.7    
Unrecognized restricted stock units compensation expense, weighted average recognition period 1 year 7 months 6 days    
Restricted stock units | Minimum      
Share Based Payments Disclosure [Line Items]      
Stock units granted, ratable vesting period 3 years    
Restricted stock units | Maximum      
Share Based Payments Disclosure [Line Items]      
Stock units granted, ratable vesting period 5 years