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Share-Based Compensation Plans - Options Activity (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Performance-based options      
Shares (in thousands)      
Outstanding beginning balance (in shares) 446,200    
Forfeited or expired (in shares) 0    
Exercised (in shares) (271,800)    
Outstanding ending balance (in shares) 174,400    
Expected to vest in future periods (in shares) 0    
Weighted-Average Grant Date Fair Value Per Share      
Beginning balance (in dollars per share) $ 14.70    
Forfeited or expired (in dollars per share) 0    
Exercised (in dollars per share) 12.64    
Ending balance (in dollars per share) 17.92    
Outstanding beginning balance (in dollars per share) 61.23    
Forfeited or expired (in dollars per share) 0    
Exercised (in dollars per share) 53.39    
Outstanding ending balance (in dollars per share) $ 73.45    
Exercisable (in shares) 174,400 446,200 946,500
Exercisable (in dollars per share) $ 73.45 $ 61.23 $ 45.36
Expected to vest in future periods (in dollars per share) $ 0    
Outstanding, Weighted-Average Remaining Contractual Term (in years) 1 month 6 days    
Exercisable, Weighted-Average Remaining Contractual Term (in years) 1 month 6 days    
Outstanding, Aggregate Intrinsic Value (in millions) $ 2.5    
Exercisable, Aggregate Intrinsic Value (in millions) 2.5    
Expected to vest in future periods, Aggregate Intrinsic Value (in millions) $ 0.0    
Market price (in dollars per share) $ 87.95    
Time Based Vesting Option      
Shares (in thousands)      
Outstanding beginning balance (in shares) 161,600    
Forfeited or expired (in shares) (12,900)    
Exercised (in shares) (33,000.0)    
Outstanding ending balance (in shares) 115,700    
Expected to vest in future periods (in shares) 0    
Weighted-Average Grant Date Fair Value Per Share      
Beginning balance (in dollars per share) $ 21.41    
Forfeited or expired (in dollars per share) 21.35    
Exercised (in dollars per share) 21.36    
Ending balance (in dollars per share) 21.43    
Outstanding beginning balance (in dollars per share) 81.13    
Forfeited or expired (in dollars per share) 82.16    
Exercised (in dollars per share) 82.08    
Outstanding ending balance (in dollars per share) $ 80.74    
Exercisable (in shares) 115,700 102,700 2,700
Exercisable (in dollars per share) $ 80.74 $ 79.26 $ 84.65
Expected to vest in future periods (in dollars per share) $ 0    
Outstanding, Weighted-Average Remaining Contractual Term (in years) 1 year 4 months 24 days    
Exercisable, Weighted-Average Remaining Contractual Term (in years) 1 year 4 months 24 days    
Outstanding, Aggregate Intrinsic Value (in millions) $ 0.8    
Exercisable, Aggregate Intrinsic Value (in millions) 0.8    
Expected to vest in future periods, Aggregate Intrinsic Value (in millions) $ 0.0    
Market price (in dollars per share) $ 87.95    
Expected forfeiture rate 5.00%