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Borrowings and Other Obligations - Subordinated Debt (Details) - USD ($) $ in Thousands		3 Months Ended
	Mar. 15, 2021	Mar. 31, 2021	Mar. 31, 2020	Nov. 29, 2013
Debt Instrument [Line Items]
Accretion of discount on subordinated debenture		$ 1,347	$ 17
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	5.70%
Accretion of discount on subordinated debenture	$ 1,300		$ 17