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Securities - Narrative (Details) $ in Thousands | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2018 USD ($) | Sep. 30, 2018 USD ($) | Sep. 30, 2019 USD ($) Security | Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Gross gains on sales of securities available for sale | $ | $ 31 | $ 44 |  |
Carrying value of securities pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes | $ |  |  | $ 174,308 | $ 165,792
U.S. Government and agencies |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available for sale securities in unrealized loss positions for 12 months or more |  |  | 31 |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) |  |  | 1.00% |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |
Held to maturity securities in unrealized loss positions for 12 months or more |  |  | 2 |
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) |  |  | 1.00% |
Mortgage-backed securities, residential |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available for sale securities in unrealized loss positions for 12 months or more |  |  | 2 |
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 |  |  | 6 |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |
Held to maturity securities in unrealized loss positions for 12 months or more |  |  | 8 |
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 |  |  | 11 |
State and municipal |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |
Available for sale securities in unrealized loss positions for 12 months or more |  |  | 3 |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) |  |  | 1.00% |

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