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Asset Purchases (Tables) | 6 Months Ended
--- | ---
Jun. 30, 2018
Business Combinations [Abstract] |
Amortization Expense of Core Deposit Intangible Assets |
|  | (In Thousands) |
|  | Custar |
2018 |  | $ | 167 |
2019 |  |  | 167 |
2020 |  |  | 161 |
|  | $ | 495 |

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