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Basis of Presentation and Changes in Significant Accounting Policies (Details) - USD ($) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2019
ACL for loans and leases | $ 300,000 | $ 2,100,000 | $ 8,000,000.0 |  |
Change in allowance for credit loss |  |  |  | $ 10,400,000 |
ACL on loans and leases | 1,300,000 | 1,400,000 | 5,200,000 |  |
Reserve for unfunded commitments | 980,000 | $ 734,000 | 2,500,000 |  |
Retained earnings | 228,825,000 |  |  | 228,825,000 | $ 213,723,000
Goodwill | $ 18,600,000 |  |  | $ 18,600,000 |
Accounting Standards Update 2016-13 | Revision of Prior Period, Adjustment [Member] |  |  |  |  |
ACL on loans and leases |  |  | 5,900,000 |  |
Reserve for unfunded commitments |  |  | 1,700,000 |  |
ACL increase from non-accretable purchase accounting adjustments |  |  | $ 2,500,000 |  |
Retained earnings |  |  |  |  | (3,700,000)
Deferred tax assets |  |  |  |  | $ 1,400,000

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