Annual report pursuant to Section 13 and 15(d)

Stock Plans and Management Compensation (Details 1)

v3.22.4
Stock Plans and Management Compensation (Details 1) - USD ($)
$ / shares in Units, shares in Thousands, $ in Millions
12 Months Ended
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Shares Available for Grant (in shares) 4,400    
Non-Vested Stock Awards [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee   62 years  
Share-Based Compensation Expense $ 18.2 $ 16.3 $ 13.3
Share-Based Compensation Expense, Tax Benefit 4.5 4.0 3.3
Fair Value of Shares Vested During the Period $ 16.7 $ 11.3 $ 6.6
Weighted Average Grant Date Fair Value $ 82.14 $ 66.81  
Awarded - Weighted Average Grant Date Fair Value 93.62 $ 91.14 $ 64.13
Forfeited - Weighted Average Grant Date Fair Value 83.15    
Vested - Weighted Average Grant Date Fair Value $ 51.32    
Share-Based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]      
Outstanding at January 1 635    
Awarded 226    
Forfeited (28)    
Vested (232)    
Outstanding at December 31 601 635  
Unrecognized Compensation Cost $ 12.5    
Non-Vested Stock Awards [Member] | Minimum [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Age of Grantee plus Grantees Total Number of Years of Service 70 years    
Performance Shares [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-Based Compensation Expense $ 3.6 $ 13.5 $ 13.8
Share-Based Compensation Expense, Tax Benefit 0.9 3.3 3.4
Fair Value of Shares Vested During the Period $ 14.6 $ 18.6 $ 3.4
Weighted Average Grant Date Fair Value $ 90.97 $ 76.15  
Awarded - Weighted Average Grant Date Fair Value 70.32    
Forfeited - Weighted Average Grant Date Fair Value 81.31    
Vested - Weighted Average Grant Date Fair Value $ 56.11    
Share-Based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward]      
Outstanding at January 1 192    
Awarded 207    
Forfeited (5)    
Vested (203)    
Outstanding at December 31 191 192  
Unrecognized Compensation Cost $ 3.3