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Securities - Narrative (Details) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 USD ($) Security | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) Security | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Gross gains on sales of securities available for sale | $ | $ 0 | $ 12,500 | $ 0 | $ 12,500 |
Carrying value of securities pledged as collateral as required by law on public and trust deposits, repurchase agreements, and for other purposes | $ | $ 138,082,000 |  | $ 138,082,000 |  | $ 165,792,000
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 | 34 |  | 34 |  |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 2.00% |  | 2.00% |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |
Held to maturity securities in unrealized loss positions for 12 months or more | 4 |  | 4 |  |
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 1.00% |  | 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 | 5 |  | 5 |  |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 1.00% |  | 1.00% |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |
Held to maturity securities in unrealized loss positions for 12 months or more | 14 |  | 14 |  |
Held to maturity securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 1.00% |  | 1.00% |  |
State and municipal |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Available for sale securities in unrealized loss positions for 12 months or more | 5 |  | 5 |  |
Available for sale securities in unrealized loss positions, percentage of amortized cost (individually did not exceed) | 1.00% |  | 1.00% |  |

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