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Loans (Details 1) (Parenthetical) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Receivables Acquired with Deteriorated Credit Quality | National Bancshares Corporation |  |
Financing Receivable Impaired [Line Items] |  |
Acquired with deteriorated credit quality, allowances | $ 0 | $ 0

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