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Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unrecognized compensation expense to be recognized | $ 3.6 |  |
Weighted average compensation expense recognize period | 1 year 9 months 7 days |  |
Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Compensation expense | $ 2.4 | $ 1.9 | $ 3.0
Tax benefit realized on compensation expense | $ 0.5 | $ 0.4 | $ 1.1
2014 Stock Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Maximum number of common stock authorized (in shares) | 750,000 |  |
Stock plan expiration period | 10 years |  |
Number of nonstatutory stock options outstanding (in shares) | 0 |  |
2014 Stock Plan | Restricted Stock |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted shares granted (in shares) | 84,882 | 75,997 |
2014 Stock Plan | Restricted Stock | Employees and Directors |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted shares granted (in shares) | 529,933 |  |
2014 Stock Plan | Restricted Stock | Outside Directors |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted shares granted (in shares) | 11,231 | 9,264 | 12,728
Awards vesting period | 1 year |  |
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) | 73,651 | 66,733 | 77,387
LTIP | Time-based Restricted Shares | Senior Management |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Restricted stock award vesting after year two, percent | 50.00% |  |
Restricted stock award vesting after year three, percent | 50.00% |  |
LTIP | Performance-based Restricted Shares | Senior Management |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Awards vesting period | 3 years |  |

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