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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 |

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