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Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Additional Information (Details) $ in Millions |  | 12 Months Ended | 84 Months Ended
--- | --- | --- | ---
Oct. 02, 2020 USD ($) shares | Dec. 31, 2020 USD ($) seniorExecutiveOfficer shares | Dec. 31, 2019 USD ($) shares | Dec. 31, 2018 USD ($) shares | Dec. 31, 2020 USD ($) seniorExecutiveOfficer shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unrecognized compensation expense to be recognized | $ |  | $ 4.2 |  |  | $ 4.2
Weighted average compensation expense recognize period (in years) |  | 2 years 1 month 28 days |  |  |
Restricted Stock |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Compensation expense | $ |  | $ 0.7 | $ 2.4 | $ 1.9 |
Tax benefit realized on compensation expense | $ |  | $ 0.2 | $ 0.5 | $ 0.4 |
2014 Stock Plan |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Maximum number of common stock authorized (in shares) |  | 750,000 |  |  | 750,000
Stock plan expiration period (in years) |  | 10 years |  |  |
Number of nonstatutory stock options outstanding (in shares) |  | 0 |  |  | 0
2014 Stock Plan | Restricted Stock |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted shares granted (in shares) |  | 230,703 | 84,882 |  | 760,636
Forfeited (in shares) |  | 58,741 | 33,228 |  | 136,896
Grants in period (in shares) |  |  |  |  | 623,740
2014 Stock Plan | Restricted Stock | Outside Directors |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted shares granted (in shares) |  | 23,153 | 11,231 | 9,264 |
Awards vesting period (in years) |  | 1 year |  |  |
LTIP | Restricted Stock | Other Executive Officers | Tranche One |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted stock award vesting (as a percent) |  | 33.00% |  |  |
LTIP | Restricted Stock | Other Executive Officers | Tranche Two |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted stock award vesting (as a percent) |  | 33.00% |  |  |
LTIP | Restricted Stock | Other Executive Officers | Tranche Three |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted stock award vesting (as a percent) |  | 34.00% |  |  |
LTIP | Time-based and Performance-based Restricted Stocks | Senior Management |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted shares granted (in shares) |  | 207,550 | 73,651 | 66,733 |
LTIP | Time-based and Performance-based Restricted Stocks | Senior Executive Officers |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted shares granted (in shares) |  | 83,669 |  |  |
Number of senior executive officers granted stock | seniorExecutiveOfficer |  | 3 |  |  | 3
LTIP | Time-based and Performance-based Restricted Stocks | Other Executive Officers |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted shares granted (in shares) |  | 62,753 |  |  |
Compensation expense | $ |  | $ 1.3 |  |  |
Number of other senior executive officers granted stock | seniorExecutiveOfficer |  | 2 |  |  | 2
LTIP | Time-based Restricted Shares | Senior Management | Tranche One |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Awards vesting period (in years) |  | 2 years |  |  |
Restricted stock award vesting (as a percent) |  | 50.00% |  |  |
LTIP | Time-based Restricted Shares | Senior Management | Tranche Two |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Awards vesting period (in years) |  | 1 year |  |  |
Restricted stock award vesting (as a percent) |  | 50.00% |  |  |
LTIP | Performance-based Restricted Shares | Senior Management |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Awards vesting period (in years) |  | 3 years |  |  |
Modified 2014 Stock Plan | Chief Executive Officer |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Period of transition to advisory service role upon retirement | 3 years |  |  |  |
Modified 2014 Stock Plan | Restricted Stock |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Forfeited (in shares) | 20,916 |  |  |  |
Compensation expense | $ | $ (0.3) |  |  |  |

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