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Employee Benefits (Detail Textuals) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Percentage of internal revenue contribution |  |  | 25.00% |  |
Percentage of internal revenue service limitations |  |  | 6.00% |  |
Cash surrender value of life insurance | $ 18,218 |  | $ 18,218 |  | $ 18,018
Increase in cash surrender value of insurance | 99 | $ 100 | 200 | $ 199 |
Accrued expenses and other liabilities | 10,573 |  | 10,573 |  | 10,108
Noninterest expense | 7,048 | $ 6,401 | 13,966 | 12,767 |
Employer contribution in defined contribution plan |  |  | 442 | 378 | 570
Net earnings on Bank Owned Life Insurance |  |  | 200 | 199 |
Directors' Plan |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Accrued expenses and other liabilities | 1,918 |  | 1,918 |  | 1,687
Noninterest expense |  |  | 62 | 65 |
Executive Long-Term Incentive and Retention Plan |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Accrued expenses and other liabilities | 998 |  | 998 |  | 975
Noninterest expense |  |  | $ 271 | 175 |
Executive Long-Term Incentive and Retention Plan | Maximum |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Terms of services |  |  | 5 years |  |
Executive Long-Term Incentive and Retention Plan | Minimum |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Terms of services |  |  | 1 year |  |
Group Term Replacement Plan |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Liability related to these postretirement benefits | 1,303 |  | $ 1,303 |  | 1,276
Postemployment benefit expense |  |  | 26 | 26 |
Other Director and Officer Postretirement Benefits |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Noninterest expense |  |  | 48 | $ 51 |
Liability related to these postretirement benefits | $ 2,124 |  | $ 2,124 |  | $ 2,108
Other Director and Officer Postretirement Benefits | Maximum |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Post retirement benefit period |  |  | 20 years |  |
Other Director and Officer Postretirement Benefits | Minimum |  |  |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |  |  |
Post retirement benefit period |  |  | 15 years |  |

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