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Stock-Based Compensation, Stock Award and Incentive Plan and Stock Options (Details) - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Employee service share-based compensation, aggregate disclosures [Abstract]      
Share based compensation costs $ 10.7 $ 10.2 $ 8.1
Stock Options [Member]      
Employee service share-based compensation, aggregate disclosures [Abstract]      
Term of stock options granted under Plan 10 years    
Vesting period 3 years    
Share based compensation costs $ 4.9 4.6 4.8
Tax benefit of share-based compensation $ 1.3 $ 1.2 $ 1.3
Forfeiture rate assumed 8.38% 8.45% 8.85%
Weighted average grant date fair value for stock options granted (in dollars per share) $ 21.62 $ 18.99 $ 18.86
Weighted average grant date fair value for stock options vested (in dollars per share) $ 20.56 $ 23.85 $ 22.46
Total intrinsic value of stock options exercised $ 6.1 $ 2.3 $ 2.2
Weighted Average Assumptions [Abstract]      
Expected life 6 years 10 months 24 days 6 years 8 months 12 days 6 years 7 months 6 days
Interest rate 0.71% 1.67% 2.62%
Volatility 32.04% 30.34% 30.26%
Expected dividend yield 0.31% 0.35% 0.37%
Stock Options [Roll Forward]      
Balance, beginning of year (in shares) 1,363,366    
Granted (in shares) 255,769    
Exercised (in shares) (251,195)    
Canceled (in shares) (37,938)    
Balance, end of year (in shares) 1,330,002 1,363,366  
Exercisable, end of year (in shares) 834,060    
Weighted Average Exercise Price Per Share [Abstract]      
Balance, beginning of year (in dollars per share) $ 57.29    
Granted (in dollars per share) 66.00    
Exercised (in dollars per share) 51.12    
Canceled (in dollars per share) 64.92    
Balance, end of year (in dollars per share) 59.91 $ 57.29  
Exercisable, end of year (in dollars per share) $ 59.09    
Weighted Average Remaining Contractual Life [Abstract]      
Outstanding options, end of year 6 years 1 month 20 days    
Exercisable options, end of year 4 years 9 months 18 days    
Aggregate Intrinsic Value [Abstract]      
Outstanding options, end of year $ 18.7    
Exercisable options, end of year $ 12.8    
Additional Information [Abstract]      
Closing stock price on last business day of the period (in dollars per share) $ 73.15    
Weighted average intrinsic value of options exercised (in dollars per share) $ 24.43 $ 24.41 $ 27.21
Unrecognized stock-based compensation expense $ 4.9    
Weighted average period over which unrecognized stock-based compensation expense is expected to be recognized 3 years    
Nonvested Stock Options [Member]      
Stock Options [Roll Forward]      
Balance, beginning of year (in shares) 487,160    
Granted (in shares) 255,769    
Vested (in shares) (225,402)    
Canceled (in shares) (21,585)    
Balance, end of year (in shares) 495,942 487,160  
Weighted Average Exercise Price Per Share [Abstract]      
Balance, beginning of year (in dollars per share) $ 58.61    
Granted (in dollars per share) 66.00    
Vested (in dollars per share) 60.88    
Canceled (in dollars per share) 61.11    
Balance, end of year (in dollars per share) $ 61.28 $ 58.61