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Securities - Narrative (Details) | Mar. 31, 2019 USD ($) Security | Dec. 31, 2018 USD ($)
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Debt Securities, Available-for-sale [Line Items] |  |
Carrying value of securities pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes | $ | $ 164,002,000 | $ 165,792,000
U.S. Government and agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 4.00% |
Available for sale securities in unrealized loss positions for 12 months or more | 48 |
Schedule of Held-to-maturity Securities [Line Items] |  |
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 1.00% |
Held to maturity securities in unrealized loss positions for 12 months or more | 5 |
Mortgage-backed securities, residential |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available for sale securities in unrealized loss positions | 22 |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 15.00% |
Available for sale securities in unrealized loss positions for 12 months or more | 20 |
Schedule of Held-to-maturity Securities [Line Items] |  |
Held to maturity securities in unrealized loss positions | 27 |
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 2.00% |
Held to maturity securities in unrealized loss positions for 12 months or more | 24 |
State and municipal |  |
Debt Securities, Available-for-sale [Line Items] |  |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 2.00% |
Available for sale securities in unrealized loss positions for 12 months or more | 7 |

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