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Stock-Based Compensation (Details Textual) - USD ($) | 1 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 16, 2013 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
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 |  |  |
Intrinsic value of stock options exercised |  | $ 0 | $ 0 | $ 664,321
Proceeds from stock options exercised |  | 0 | 0 | 354
Weighted average grant date fair value of restricted stock that vested during |  | 2,276,000 | 2,385,000 | 2,300,000
Net value of unrecognized compensation cost related to unvested restricted stock awards |  | 4,195,000 | 4,166,000 | 4,063,000
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock-Based Compensation expense |  | 2,129,000 | 2,201,000 | 2,279,000
Recognized tax benefits |  | $ 227,000 | $ 251,000 | $ 912,000
Class A Common Stock | Convert For Class B [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |
Class A Common Stock | Stock Option [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 990,000 |  |  |
Class A Common Stock | Incentive Compensation Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 620,000 |  |  |
Class B Common Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Increase in number of common stock shares authorized | 90,000 |  |  |
Class B Common Stock | Stock Option [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 370,000 |  |  |

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