Annual report pursuant to Section 13 and 15(d)

Share-Based Compensation - Additional Information (Detail)

v3.25.0.1
Share-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
12 Months Ended
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Apr. 26, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common shares authorized under 2014 Stock Incentive Plan 24,800,000      
Common shares remain for future issuance under share-based compensation plans 8,300,000      
Realized income tax benefit for all awards $ 7.9 $ 11.2 $ 10.4  
Tax deficiencies on share-based compensation arrangements 6.5 5.2 0.6  
Total vesting date fair value of stock units $ 22.6 27.2 38.0  
Reserved for issuance under employee stock purchase plan 4,000,000      
Future issuance of employee stock purchase plan 2,400,000      
Percent of fair market value for which eligible employees can purchase common shares under employee stock purchase plan 85.00%      
Weighted-average grant date fair value of SARs granted $ 9.41      
Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total intrinsic value of awards granted for SARs   0.0 $ 0.0  
Total intrinsic value of awards exercised for SARs $ 0.0 $ 0.0    
Performance conditions [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
SARs granted 0 0    
Chief Executive Officer [Member] | Performance conditions [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting date     Dec. 31, 2024  
Stock options and SARs [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Contractual term 10 years      
Stock Appreciation Rights (SARs)        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted-average grant date fair value of SARs granted $ 4.61 $ 7.83 $ 6.38  
SARs granted [1] 7,364,000      
Stock Appreciation Rights (SARs) | Performance conditions [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Awards granted 0      
SARs granted   0 0  
Stock Appreciation Rights (SARs) | Service condition [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period beginning from the grant date 2 years 3 years    
Stock Appreciation Rights (SARs) | Stock Incentive Plan Other [Member] | Performance conditions [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period beginning from the grant date 3 years      
Stock Appreciation Rights (SARs) | Chief Executive Officer [Member] | Service condition [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period beginning from the grant date     2 years  
Service condition awards [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense (benefit) $ 49.9 $ 49.5 $ 44.5  
Unrecognized compensation cost on non-vested stock awards $ 58.7      
Unrecognized compensation cost on non-vested stock awards, weighted-average period of recognition 1 year 7 months 6 days      
Total intrinsic value of awards exercised for options and SARs     0.4  
Service condition awards [Member] | Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total intrinsic value of awards exercised for options and SARs   0.1    
Performance condition awards [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense (benefit) $ 0.1 $ (1.5) (0.1)  
Unrecognized compensation cost on non-vested stock awards $ 0.0      
Total intrinsic value of awards exercised for options and SARs     $ 0.1  
Weighted-average grant date fair value of SARs granted $ 4.41      
Performance condition awards [Member] | Independent Director Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period beginning from the grant date 1 year      
Performance condition awards [Member] | Chief Executive Officer [Member] | Minimum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting percentage     0.00%  
Performance condition awards [Member] | Chief Executive Officer [Member] | Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting percentage     200.00%  
Management Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Additional awards 0      
2014 Stock Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Additional awards 0      
2005 Stock Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Additional awards 0      
2023 Stock Incentive Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Common shares remain for future issuance under share-based compensation plans       24,200,000
Awards granted 0      
Stock Incentive Plan [Member] | Performance condition awards [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period beginning from the grant date 3 years      
Contractual term 3 years      
[1] Includes 3.4 million performance condition SARs granted to a consultant.