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Share-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended 72 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation cost related to unvested share-based equity awards $ 51.5      
Weighted average period of recognition of unvested share-based equity awards (in years) 1 year 3 months 18 days      
Unrecognized compensation cost related to unvested share-based equity awards, Stock Options $ 5.4      
Unrecognized compensation cost related to unvested share-based equity awards, Restricted Stock $ 46.1      
Weighted average remaining contractual life of option outstanding 4 years 10 months 24 days      
Weighted average remaining contractual life of option exercisable 3 years 10 months 24 days      
Estimated weighted average fair value of options granted $ 43.39 $ 37.41 $ 36.77  
Total intrinsic value of options exercised $ 13.5      
Total intrinsic value of options outstanding 28.5      
Total intrinsic value of options exercisable $ 28.3      
Weighted average fair values at the grant dates of grants awarded $ 138.98 $ 146.08 $ 165.54  
Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 0.00%      
Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 200.00%      
Omnibus Incentive Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum number of shares of common stock available for issuance 27,775,000      
Omnibus Incentive Plan | Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock option awards granted, vesting period 1 year      
Omnibus Incentive Plan | Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock option awards granted, vesting period 3 years      
Omnibus Incentive Plan | Deferred Stock Units | Non-employee directors        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common stock shares granted 16,000 17,000 10,000  
Additional shares issued to retired directors 12,000 11,000 8,000 79,000
Omnibus Incentive Plan | Deferred Stock Units | Non-employee directors | Since 2007        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common stock shares granted 258,000      
Stock Option Plans        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common stock shares granted 294,359      
Directors Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum shares authorized for issuance 500,000      
Shares of common stock earned 73,000      
Additional shares issued to retired directors 427,000      
Liabilities under share plan $ 9.6 $ 9.2   $ 9.2
Performance Shares        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Granted 66,551      
Restricted Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Granted 382,508      
Total intrinsic value of restricted stock expected to vest $ 75.5      
Weighted average fair values at the grant dates of grants awarded $ 110.39 $ 119.42 $ 122.08