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Summary of Significant Accounting Policies - Accounting Pronouncement (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2020 | Jan. 01, 2020
Retained earnings | $ 213,723 | $ 236,579 |
Deferred tax assets | 18,481 | $ 18,972 |
Accounting Standards Update 2016-13 | Revision of Prior Period, Adjustment [Member] |  |  |
ACL on loans and leases | 5,900 |  |
Reserve for unfunded commitments | 1,700 |  |
ACL increase from non-accretable purchase accounting adjustments | $ 2,500 |  |
Retained earnings |  |  | $ 3,800
Deferred tax assets |  |  | $ 1,400

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