Quarterly report pursuant to Section 13 or 15(d)

Share-Based Compensation - Additional Information (Detail)

v3.24.3
Share-Based Compensation - Additional Information (Detail) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2024
Sep. 30, 2023
Sep. 30, 2024
Sep. 30, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Share-based compensation expense $ 13.0 $ 13.7 $ 36.7 $ 35.7
Weighted-average grant date fair value of SARs granted     $ 9.42  
Total vesting date fair value of stock units 0.1 1.0 $ 17.2 23.8
Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Total intrinsic value of awards exercised for SARs $ 0.0 $ 0.1 $ 0.0 $ 0.1
Share-Based Payment Arrangement, Tranche One [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting date     Mar. 31, 2025  
Share-Based Payment Arrangement, Tranche Two [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting date     Mar. 31, 2026  
Share-Based Payment Arrangement, Tranche Three [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Performance stock unit awards vesting date     Mar. 31, 2027  
SARs [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Weighted-average grant date fair value of SARs granted $ 5.36 $ 10.3 $ 4.52 $ 7.93
SARs granted [1]     7,364  
SARs exercised     0  
Service Condition Awards [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unrecognized compensation cost on non-vested stock awards $ 73.7   $ 73.7  
Unrecognized compensation cost on non-vested stock awards, weighted-average period of recognition     1 year 8 months 12 days  
[1] Includes 3.4 million performance condition SARs granted to a consultant.