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v3.21.1

Restricted Stock and Stock Options - Additional Information (Detail) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 USD ($) Incentive_Plan shares | Mar. 31, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of equity incentive plans | Incentive_Plan | 2 |
Market value of shares | $ |  | $ 13.7
Stock options exercised, Shares | 0 |
Stock options outstanding | 0 |
Share-based compensation expense | $ | $ 0.6 | $ 0.8
Restricted Stock [Member] | Non-employee Directors [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common stock issued, shares | 0 | 201
Performance Awards [Member] | Non-employee Directors [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common stock issued, shares | 0 |

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