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Merger - Narrative (Details) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2021 USD ($) | Aug. 06, 2021 USD ($) shares | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Business Combination, Separately Recognized Transactions [Line Items] |  |  |  |  |
Goodwill | $ 72,754 |  | $ 72,754 | $ 30,140 |
Core deposit intangible | 6,605 |  | 6,605 | 3,831 |
Amortization of core deposit intangible |  |  | $ 1,135 | $ 853 | $ 887
American River Bank (ARB) Merger |  |  |  |  |
Business Combination, Separately Recognized Transactions [Line Items] |  |  |  |  |
Goodwill |  | $ 42,614 |  |  |
American River Bank (ARB) Merger | Common Stock |  |  |  |  |
Business Combination, Separately Recognized Transactions [Line Items] |  |  |  |  |
Fixed exchange ratio |  | 0.575 |  |  |
American River Bank (ARB) Merger | Core deposit intangible |  |  |  |  |
Business Combination, Separately Recognized Transactions [Line Items] |  |  |  |  |
Core deposits, amortization period |  |  | 10 years |  |
Core deposit intangible |  | $ 3,900 |  |  |
Amortization of core deposit intangible | $ 318 |  |  |  |
American River Bank (ARB) Merger | Bank of Marin |  |  |  |  |
Business Combination, Separately Recognized Transactions [Line Items] |  |  |  |  |
Business combination, number of common stock issued (in shares) | shares |  | 3,441,235 |  |  |

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