Significant Accounting Policies (Stock-based Compensation and Other) (Details) - Class A Common Stock - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
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)	138,306	79,380
Class A common stock available for issuance under the plan (shares)	561,694
Compensation expense related to share awards	$ 4,100,000	$ 2,000,000
Compensation expense related to share awards, net of tax	3,200,000	1,600,000
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
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)	166,561
Compensation expense related to share awards	$ 1,300,000	1,000,000
Compensation expense related to share awards, net of tax	$ 1,100,000	$ 800,000
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)	45,223	42,744
Amount of directors, annual retainer paid in restricted shares	$ 105,000	$ 100,000
Annual non-employee directors retainer amount	$ 167,000	$ 162,000
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)	753	745
Percentage of annual retainer that may be received in shares of Class A stock (percent)	100.00%
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
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
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
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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