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Accounting Pronouncements Recently Issued Narrative - Impact of implementation of new accounting standards (Details) - USD ($) $ in Thousands | Jan. 01, 2020 | Dec. 31, 2019 | Dec. 31, 2018
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Accounting Standards Update 2016-02 [Member] |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  | $ (2,457) |
Accounting Standards Update 2016-01 [Member] |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ 782
Accounting Standards Update 2016-13 [Member] |  |  |
Change in allowance for credit losses due to adoption of new ASU | $ 1,632 |  |
Change in allowance for unfunded commitments and letters of credit due to adoption of new ASU | $ 1,570 |  | 0
Retained Earnings [Member] | Accounting Standards Update 2016-02 [Member] |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  | (2,457) |
Retained Earnings [Member] | Accounting Standards Update 2016-01 [Member] |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  |  | $ 782
Retained Earnings [Member] | Accounting Standards Update 2016-13 [Member] |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption |  | $ (2,500) |

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