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Investment Securities - Securities Sold and Pledged as Collateral (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale:
Sales proceeds	$ 33,756	$ 66,081	$ 16,972
Gross realized gains	916	214	27
Gross realized losses	(1)	(159)	$ (106)
Available-for-sale securities pledged as collateral	132,431	127,962
Public Deposits
Available-for-sale:
Available-for-sale securities pledged as collateral	131,051	126,598
Trust Deposits
Available-for-sale:
Available-for-sale securities pledged as collateral	751	742
State of California
Available-for-sale:
Available-for-sale securities pledged as collateral	131,802	127,340
Internal checking account
Available-for-sale:
Available-for-sale securities pledged as collateral	$ 629	$ 622

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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