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Borrowings and Other Obligations - Subordinated Debt (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Mar. 15, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2013
Debt Instrument [Line Items]
Accretion of discount on subordinated debenture			$ 1,347	$ 52
Subordinated debenture \| NorCal Community Bancorp Trust II
Debt Instrument [Line Items]
Contractual value of subordinated debt					$ 4,100
Repayments of debt	$ 2,800
Effective interest rate		6.00%	251.50%	6.00%
Accretion of discount on subordinated debenture		$ 17	$ 1,300	$ 52