Summary of Significant Accounting Policies - Goodwill and Other Intangible Assets - Useful Lives (Details) - Core Deposits [Member]	12 Months Ended
Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	8 years
Citizen's Business Bank Porterville Branch [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Asset, Useful Life	5 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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