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Stock-Based Compensation (Narrative) (Details) - USD ($) | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Oct. 16, 2013 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2018
Stock Based Compensation [Abstract] |  |  |  |  |  |
Stock-Based Compensation expense |  | $ 0 | $ 0 | $ 0 | $ 0 |
Stock options granted |  | 0 | 0 | 0 | 0 |
Stock options outstanding |  | 0 |  | 0 |  |
Increase in number of common stock shares authorized | 233,334 |  |  |  |  |
Percentage to retain annual restricted stock awards | 50.00% |  |  |  |  |
Stock options exercise price description |  |  |  | may not be exercised at a price which is less than 100% of the fair market value of shares at the date of grant |  |
Restricted Stock [Member] |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Stock-Based Compensation expense |  | $ 348,000 | $ 618,000 | $ 1,048,000 | $ 1,799,000 |
Recognized tax benefits |  | $ 30,000 | $ 71,000 | $ 94,000 | $ 198,000 |
Class A Common Stock | Stock Option [Member] |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 990,000 |  |  |  |  |
Class A Common Stock | Incentive Compensation Plan [Member] |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 620,000 |  |  |  |  |
Class A Common Stock | Convert For Class B [Member] |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |  |  |
Class B Common Stock |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Increase in number of common stock shares authorized |  |  |  |  |  | 90,000
Class B Common Stock | Stock Option [Member] |  |  |  |  |  |
Stock Based Compensation [Abstract] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |  |  |

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