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Significant Accounting Policies (Stock-based Compensation and Other) (Details) - Class A Common Stock - USD ($) | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022
Executives | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued during the year under the Company's stock compensation plans (shares) | 120,649 | 165,574
Class A common stock available for issuance under the plan (shares) | 779,351 |
Compensation expense related to share awards | $ 4,100,000 | $ 6,400,000
Compensation expense related to share awards, net of tax | $ 3,300,000 | 5,000,000
Non-employee Directors | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Class A common stock available for issuance under the plan (shares) | 98,479 |
Compensation expense related to share awards | $ 1,300,000 | 1,300,000
Compensation expense related to share awards, net of tax | $ 1,100,000 | $ 1,000,000
Non-employee Directors | Restricted Stock |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued during the year under the Company's stock compensation plans (shares) | 35,965 | 30,034
Amount of directors, annual retainer paid in restricted shares | $ 110,000 | $ 110,000
Annual non-employee directors retainer amount | $ 175,000 | $ 175,000
Non-employee Directors | Voluntary Shares |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Shares issued during the year under the Company's stock compensation plans (shares) | 1,603 | 480
Percentage of annual retainer that may be received in shares of Class A stock (percent) | 100.00% |
Chairman | Restricted Stock |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Amount of directors, annual retainer paid in restricted shares | $ 150,000 | $ 150,000
Annual non-employee directors retainer amount | $ 250,000 | $ 250,000
Participant's Retirement Date | Executives | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 3 years |
Award Date | Executives | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 5 years |
Award Date | Non-employee Directors | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 10 years |
Participants Retirement from Board of Directors | Non-employee Directors | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 5 years |
Minimum Age of Director Upon Retirement from Board | Non-employee Directors | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 70 years |
Minimum | Award Date | Executives | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 3 years |
Maximum | Award Date | Executives | Share-based Payment Arrangement |  |
Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Duration of restrictions on stock assignment, pledges or transfers | 10 years |

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