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Investment Securities - Securities Sold and Pledged as Collateral (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Available-for-sale:
Sales proceeds	$ 6,632	$ 33,756	$ 66,081
Gross realized gains	1	916	214
Gross realized losses	(17)	(1)	$ (159)
Available-for-sale securities pledged as collateral	217,849	132,431
Public Deposits
Available-for-sale:
Available-for-sale securities pledged as collateral	213,861	131,051
Trust Deposits
Available-for-sale:
Available-for-sale securities pledged as collateral	729	751
Internal checking account
Available-for-sale:
Available-for-sale securities pledged as collateral	614	629
State of California
Available-for-sale:
Available-for-sale securities pledged as collateral	215,204	132,431
Bankruptcy Trustee Deposits Pledged With Federal Reserve Bank
Available-for-sale:
Available-for-sale securities pledged as collateral	$ 2,645	$ 0

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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