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Restricted Stock and Stock Options - Additional Information (Detail) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) Incentive_Plan shares | Sep. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of equity incentive plans | Incentive_Plan |  |  | 2 |
Market value of shares | $ |  |  | $ 2.2 | $ 1.8
Stock options exercised, Shares |  |  | 0 | 0
Stock options outstanding | 0 |  | 0 |
Share-based compensation expense | $ | $ 0.4 | $ 0.8 | $ 1.7 | $ 2.6
Restricted Stock [Member] | Non-employee Directors [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock issued, shares |  |  | 8,707 | 5,269
Performance Awards [Member] | Non-employee Directors [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock issued, shares |  |  | 24,288 | 23,207

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