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Capital Stock and Dividend Restrictions (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 14, 2021 | Sep. 12, 2020 | Jun. 11, 2019
Class of Stock |  |  |  |  |  |
Common stock, shares authorized | 200,000,000 |  |  |  |  |
Stock compensation expense | $ 8.9 | $ 7.5 | $ 8.0 |  |  |
Aggregate purchase price of shares repurchased and retired | $ 5.4 | $ 116.8 | $ 2.5 |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased |  |  |  |  | 5,500,000 |
Incremental Common Shares Attributable to Dilutive Effect of Accelerated Share Repurchase Agreements | 3,000,000 |  |  |  |  |
Stock Repurchased and Retired During Period, Shares | 128,171 | 3,578,743 | 43,560 |  |  |
Sale of Stock Shares Authorized For Future Sale |  |  |  | 47,158,390 |  |
Class A Common Stock |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Stock Repurchased and Retired During Period, Shares | 72,700 |  |  |  |  |
Class A Common Stock |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Common stock, shares authorized | 100,000,000 |  |  |  |  |
Common Stock, Voting Rights, Votes Per Share | $ 1 |  |  |  |  |
Common stock, shares, outstanding | 41,699,409 | 40,335,113 |  |  |  |
Stock Repurchase Program, Number of Shares Authorized to be Repurchased |  |  |  |  |  | 2,500,000
Class B Common Stock |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Common stock, shares authorized | 100,000,000 |  |  |  |  |
Common Stock, Voting Rights, Votes Per Share | $ 5 |  |  |  |  |
Common stock, shares, outstanding | 20,501,047 | 21,760,686 |  |  |  |
Director [Member] | Class A Common Stock |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Shares issued to directors during period | 19,081 |  |  |  |  |
Stock compensation expense | $ 0.9 |  |  |  |  |
Board of Directors |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Aggregate value of shares issued to directors |  | $ 0.6 |  |  |  |
Board of Directors | Class A Common Stock |  |  |  |  |  |
Class of Stock |  |  |  |  |  |
Shares issued to directors during period |  | 19,491 |  |  |  |

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