Significant Accounting Policies (Policies)	12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]
Use of Estimates, Policy [Policy Text Block]	Accounting Estimates. Certain accounting policies underlying the preparation of these financial statements require Management to make estimates, assumptions, and judgments that affect the amounts reported in the financial statements and accompanying notes. These estimates, assumptions, and judgments are based on information available as of the date of the financial statements; accordingly, as this information changes, the financial statements could reflect different estimates, assumptions, and judgments and as such have a greater possibility of producing results that could be materially different than originally reported. Estimates, assumptions, and judgments are necessary when assets and liabilities are required to be recorded at fair value, when a decline in fair value of an asset not carried on the financial statements at fair value warrants an impairment writedown or valuation reserve to be established, or when an asset or liability needs to be recorded contingent upon a future event. The allowance for credit losses accounting is an area requiring the most subjective or complex judgments, and as such could be most subject to revision as new information becomes available. A discussion of the factors affecting the accounting for the allowance for credit losses on loans is included in the following “Loans” and “Allowance for Credit Losses” sections. Carrying assets and liabilities at fair value inherently results in financial statement volatility. The fair values and the information used to record valuation adjustments for certain assets and liabilities are based either on quoted market prices or are provided by other third party sources, when available. The “Securities” section discusses the factors that may affect the valuation of the Company’s securities. Although the estimates contemplate current conditions actual results can change.
Consolidation, Policy [Policy Text Block]	Principles of Consolidation. The consolidated financial statements include the accounts of the Company and all the Company’s subsidiaries. Significant intercompany transactions have been eliminated in consolidation. The Company does not maintain or conduct transactions with any unconsolidated special purpose entities.
Cash and Cash Equivalents, Policy [Policy Text Block]	Cash. Cash includes Due From Banks balances which are readily convertible to known amounts of cash and are generally 90 days or less from maturity at the time of initiation, presenting insignificant risk of changes in value due to interest rate changes.
Marketable Securities, Policy [Policy Text Block]	Equity Securities. Equity securities consist of marketable equity securities and mutual funds which are recorded at fair value. Unrealized gains and losses are included in net income. There were no equity securities at December 31, 2023 and December 31, 2022. Debt Securities. Debt securities consist of the securities of government sponsored entities, states, counties, municipalities, corporations, agency and non-agency mortgage-backed securities, collateralized loan obligations and commercial paper. Securities transactions are recorded on a trade date basis. The Company classifies its debt securities in one of three categories: trading, available for sale or held to maturity. Trading securities are bought and held principally for the purpose of selling them in the near term. Trading securities are recorded at fair value with unrealized gains and losses included in net income. Held to maturity debt securities are those securities which the Company has the ability and intent to hold until maturity. Held to maturity debt securities are recorded at cost, adjusted for the amortization of premiums or accretion of discounts. Securities not included in trading or held to maturity are classified as available for sale debt securities. Available for sale debt securities are recorded at fair value. Unrealized gains and losses, net of the related tax effect, on available for sale debt securities are included in accumulated other comprehensive income. Accrued interest is recorded within other assets and reversed against interest income if it is not received. The Company utilizes third-party sources to value its investment securities; securities individually valued using quoted prices in active markets are classified as Level 1 assets in the fair value hierarchy, and securities valued using quoted prices in active markets for similar securities (commonly referred to as “matrix” pricing) are classified as Level 2 assets in the fair value hierarchy. The Company validates the reliability of third-party provided values by comparing individual security pricing for securities between more than one third-party source. When third-party information is not available, valuation adjustments are estimated in good faith by Management and classified as Level 3 in the fair value hierarchy. The Company follows the guidance issued by the Board of Governors of the Federal Reserve System, “Investing in Securities without Reliance on Nationally Recognized Statistical Rating Agencies” (SR 12-15) and other regulatory guidance when performing investment security pre-purchase analysis or evaluating investment securities for credit loss. Credit ratings issued by recognized rating agencies are considered in the Company’s analysis only as a guide to the historical default rate associated with similarly-rated bonds. To the extent that debt securities in the held-to-maturity portfolio share common risk characteristics, estimated expected credit losses are calculated in a manner like that used for loans held for investment. That is, for pools of such securities with common risk characteristics, the historical lifetime probability of default and severity of loss in the event of default is derived or obtained from external sources and adjusted for the expected effects of reasonable and supportable forecasts over the expected lives of the securities on those historical credit losses. Expected credit loss on each security in the held-to-maturity portfolio that do not share common risk characteristics with any of the pools of debt securities is individually evaluated and a reserve for credit losses is established at the difference between the discounted value of the expected future cash flows, based on the original effective interest rate, and the recorded amortized cost basis of the security. For certain classes of debt securities, the bank considers the history of credit losses, current conditions and reasonable and supportable forecasts, which may indicate that the expectation that nonpayment of the amortized cost basis is or continues to be zero. Therefore, for those securities, the bank does not record expected credit losses. Available for sale debt securities in unrealized loss positions are evaluated for credit related loss at least quarterly. For available for sale debt securities, a decline in fair value due to credit loss results in recording an allowance for credit losses to the extent the fair value is less than the amortized cost basis. Declines in fair value that have not been recorded through an allowance for credit losses, such as declines due to changes in market interest rates, are recorded through other comprehensive income, net of applicable taxes. Although these evaluations involve significant judgment, an unrealized loss in the fair value of a debt security is generally considered to not be related to credit when the fair value of the security is below the carrying value primarily due to changes in risk-free interest rates, there has not been significant deterioration in the financial condition of the issuer, and the Company does not intend to sell nor does it believe it will be required to sell the security before the recovery of its cost basis. If the Company intends to sell a debt security or more likely than not will be required to sell the security before recovery of its amortized cost basis, the debt security is written down to its fair value and the write down is charged against the allowance for credit losses with any incremental loss reported in earnings. Purchase premiums are amortized to the earliest call date and purchase discounts are amortized to maturity as an adjustment to yield using the effective interest method. Unamortized premiums, unaccreted discounts, and early payment premiums are recognized as a component of gain or loss on sale upon disposition of the related security. Interest and dividend income are recognized when earned. Realized gains and losses from the sale of available for sale debt securities are included in earnings using the specific identification method.
Equity Securities without Readily Determinable Fair Value [Policy Text Block]	Nonmarketable Equity Securities. Nonmarketable equity securities include securities that are not publicly traded, such as Visa Class B common stock, and securities acquired to meet regulatory requirements, such as Federal Reserve Bank stock, which are restricted. These restricted securities are accounted for under the cost method and are included in other assets. The Company reviews those assets accounted for under the cost method at least quarterly. The Company’s review typically includes an analysis of the facts and circumstances of each investment, the expectations for the investment’s cash flows and capital needs, the viability of its business model and any exit strategy. When the review indicates that impairment exists the asset value is reduced to fair value. The Company recognizes the estimated loss in noninterest income.
Financing Receivable [Policy Text Block]	Loans. Loans are stated at the principal amount outstanding, net of unearned discount and unamortized deferred fees and costs. Interest is accrued daily on the outstanding principal balances and included in other assets. Loans which are more than 90 days delinquent with respect to interest or principal, unless they are well secured and in the process of collection, and other loans on which full recovery of principal or interest is in doubt, are placed on nonaccrual status. Interest previously accrued on loans placed on nonaccrual status is charged against interest income. In addition, some loans secured by real estate and commercial loans to borrowers experiencing financial difficulties are placed on nonaccrual status even though the borrowers continue to repay the loans as scheduled. When the ability to fully collect nonaccrual loan principal is in doubt, payments received are applied against the principal balance of the loans on a cost-recovery method until such time as full collection of the remaining recorded balance is expected. Any additional interest payments received after that time are recorded as interest income on a cash basis. Nonaccrual loans are reinstated to accrual status when none of the loan’s principal and interest is past due and improvements in credit quality eliminate doubt as to the full collectability of both principal and interest, or the loan otherwise becomes well secured and in the process of collection. Certain consumer loans or auto receivables are charged off against the allowance for credit losses when they become 120 days past due.
Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]	Allowance for Credit Losses. The Company extends loans to commercial and consumer customers primarily in Northern and Central California. These lending activities expose the Company to the risk borrowers will default, causing loan losses. The Company’s lending activities are exposed to various qualitative risks. All loan segments are exposed to risks inherent in the economy and market conditions. Significant risk characteristics related to the commercial loan segment include the borrowers’ business performance and financial condition, and the value of collateral for secured loans. Significant risk characteristics related to the commercial real estate segment include the borrowers’ business performance and the value of properties collateralizing the loans. Significant risk characteristics related to the construction loan segment include the borrowers’ performance in successfully developing the real estate into the intended purpose and the value of the property collateralizing the loans. Significant risk characteristics related to the residential real estate segment include the borrowers’ financial wherewithal to service the mortgages and the value of the property collateralizing the loans. Significant risk characteristics related to the consumer loan segment include the financial condition of the borrowers and the value of collateral securing the loans. The preparation of these financial statements requires Management to estimate the amount of expected losses over the expected contractual life of the Bank’s existing loan portfolio and establish an allowance for credit losses. Loan agreements generally include a maturity date, and the Company considers the contractual life of a loan agreement to extend from the date of origination to the contractual maturity date. In estimating credit losses, Management must exercise significant judgment in evaluating information deemed relevant. The amount of ultimate losses on the loan portfolio can vary from the estimated amounts. Management follows a systematic methodology to estimate loss potential in an effort to reduce the differences between estimated and actual losses. The allowance for credit losses is established through provisions for credit losses charged to income. Losses on loans are charged to the allowance for credit losses when all or a portion of the recorded amount of a loan is deemed to be uncollectible. Recoveries of loans previously charged off are credited to the allowance when realized. The Company’s allowance for credit losses is maintained at a level considered adequate to provide for expected losses based on historical loss rates adjusted for current and expected conditions over a forecast period. These include conditions unique to individual borrowers, as well as overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions, or credit protection agreements and other factors. Loans that share common risk characteristics are segregated into pools based on common characteristics, which is primarily determined by loan, borrower, or collateral type. Historical loss rates are determined for each pool. For consumer installment loans, primarily secured by automobiles, historical loss rates are determined using a vintage methodology, which tracks losses based on period of origination. For commercial, construction, and commercial real estate, historical loss rates are determined using an open pool methodology where losses are tracked over time for all loans included in the pool at the historical measurement date. Historical loss rates are adjusted for factors that are not reflected in the historical loss rates that are attributable to national or local economic or industry trends which have occurred but have not yet been recognized in past loan charge-off history, estimated losses based on management’s reasonable and supportable expectation of economic trends over a forecast horizon of up to two years, and other factors that impact credit loss expectations that are not reflected in the historical loss rates. Other factors include, but are not limited to, the effectiveness of the Company’s loan review system, adequacy of lending Management and staff, loan policies and procedures, problem loan trends, and concentrations of credit. At the end of the two-year forecast period loss rates revert immediately to the historical loss rates. The results of this analysis are applied to the amortized cost of the loans included within each pool. Loans that do not share risk characteristics with other loans in the pools are evaluated individually. A loan is considered ‘collateral-dependent’ when the borrower is experiencing financial difficulty and repayment is expected to be provided substantially through the operation or sale of the collateral. A credit loss reserve for collateral-dependent loans is established at the difference between the amortized cost basis in the loan and the fair value of the underlying collateral adjusted for costs to sell. For other individually evaluated loans that are not collateral dependent, a credit loss reserve is established at the difference between the amortized cost basis in the loan and the present value of expected future cash flows discounted at the loan’s effective interest rate. The impact of an expected modification to be made to loans to borrowers experiencing financial difficulty is included in the allowance for credit losses when management determines such modification is likely. Accrued interest is recorded in other assets and is excluded from the estimation of expected credit loss. Accrued interest is reversed through interest income when amounts are determined to be uncollectible, which generally occurs when the underlying receivable is placed on nonaccrual status or charged off.
Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]	Liability for Off-Balance Sheet Credit Exposures. Off-balance sheet credit exposures relate to letters of credit and unfunded loan commitments for commercial, construction and consumer loans. The Company maintains a separate allowance for credit losses from off-balance-sheet credit exposures, which is included within other liabilities on the consolidated statements of financial condition. Increases or reductions to the Company’s allowance for credit losses from off-balance sheet credit exposures are recorded in other expenses. Management estimates the amount of expected losses by estimating expected usage exposures that are not unconditionally cancellable by the Company and applying the loss factors used in the allowance for credit loss methodology to estimate the liability for credit losses related to unfunded commitments. No credit loss estimate is reported for off-balance-sheet credit exposures that are unconditionally cancellable by the Company or for undrawn amounts under such arrangements that may be drawn prior to the cancellation of the arrangement. Nonrefundable fees and certain costs associated with originating or acquiring loans are deferred and amortized as an adjustment to interest income over the contractual loan lives. Upon prepayment, unamortized loan fees, net of costs, are immediately recognized in interest income. Other fees, including those collected upon principal prepayments, are included in interest income when received. Loans held for sale are identified upon origination and are reported at the lower of cost or market value on an aggregate loan basis.
Financing Receivable, Real Estate Acquired Through Foreclosure [Policy Text Block]	Other Real Estate Owned. Other real estate owned is comprised of property acquired through foreclosure proceedings, acceptances of deeds-in-lieu of foreclosure and, if applicable, vacated bank properties. Losses recognized at the time of acquiring property in full or partial satisfaction of debt are charged against the allowance for credit losses. Other real estate owned is recorded at the fair value of the collateral, generally based upon an independent property appraisal, less estimated disposition costs. Losses incurred subsequent to acquisition due to any decline in annual independent property appraisals are recognized as noninterest expense. Routine holding costs, such as property taxes, insurance and maintenance, and losses from sales and dispositions, are recognized as noninterest expense.
Property, Plant and Equipment, Policy [Policy Text Block]	Premises and Equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed substantially on the straight-line method over the estimated useful life of each type of asset. Estimated useful lives of premises and equipment range from 20 to 50 years and from 3 to 20 years, respectively. Leasehold improvements are amortized over the terms of the lease or their estimated useful life, whichever is shorter.
Revenue from Contract with Customer [Policy Text Block]	Revenue Recognition. The Company recognizes revenue as it is earned based on contractual terms, as transactions occur, or as services are provided and collectability is reasonably assured. In certain circumstances, noninterest income is reported net of associated expenses that are directly related to variable volume-based sales or revenue sharing arrangements or when the Company acts on an agency basis for others.
Life Insurance Cash Surrender Value [Policy Text Block]	Life Insurance Cash Surrender Value. The Company has purchased life insurance policies on certain directors and officers as well as acquired such assets as part of the acquisition of other banks. Company owned life insurance is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. These assets are included in other assets on the consolidated balance sheets.
Goodwill and Intangible Assets, Policy [Policy Text Block]	Intangible Assets. Intangible assets are comprised of goodwill, core deposit intangibles and other identifiable intangibles acquired in business combinations. Intangible assets with finite useful lives are amortized on an accelerated basis over their respective estimated useful lives not exceeding 15 years. Intangible assets with a finite useful life are reviewed at least annually for impairment. Any goodwill and any intangible asset acquired in a business combination determined to have an indefinite useful life is not amortized and is reviewed at least annually for impairment. If management determines, based on a qualitative review of events and circumstances, that it is more likely than not that the carrying value of the intangible asset will not be realized, an impairment test is performed to determine whether the asset’s fair value is less than the carrying amount of the asset.
Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]	Impairment of Long-Lived Assets. The Company reviews its long-lived and certain intangible assets for impairment whenever events or changes indicate that the carrying amount of an asset may not be recoverable. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.
Income Tax, Policy [Policy Text Block]	Income Taxes. The Company and its subsidiaries file consolidated tax returns. The Company accounts for income taxes in accordance with FASB ASC 740, Income Taxes, resulting in two components of income tax expense: current and deferred. Current income tax expense approximates taxes to be paid or refunded for the current period. The Company determines deferred income taxes using the balance sheet method. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax bases of assets and liabilities, and recognizes enacted changes in tax rates and laws in the period in which they occur. Deferred income tax expense results from changes in deferred tax assets and liabilities between periods. Deferred tax assets are recognized subject to Management’s judgment that realization is more likely than not. A tax position that meets the more likely than not recognition threshold is measured to determine the amount of benefit to recognize. The tax position is measured at the largest amount of benefit that is greater than fifty percent likely of being realized upon settlement. Interest and penalties are recognized as a component of income tax expense.
Share-Based Payment Arrangement [Policy Text Block]	Stock-Based Compensation. The Company applies FASB ASC 718 – Compensation – Stock Compensation, to account for stock based awards granted to employees using the fair value method. The Company recognizes compensation expense for restricted performance share grants over the relevant attribution period. Restricted performance share grants have no exercise price, therefore, the intrinsic value is measured using an estimated per share price at the vesting date for each restricted performance share. The estimated per share price is adjusted during the attribution period to reflect actual stock price performance. The Company’s obligation for unvested outstanding restricted performance share grants is classified as a liability until the vesting date due to a cash settlement feature, at which time the issued shares become classified as shareholders’ equity.
Fiduciary [Policy Text Block]	Other. Securities and other property held by the Bank in a fiduciary or agency capacity are not included in the financial statements since such items are not assets of the Company or its subsidiaries.
Currently Adopted Accounting Pronouncements [Policy Text Block]	Recently Adopted Accounting Standards In the year ended December 31, 2021, the Company adopted the following new accounting guidance: FASB ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, was issued December 2019. The ASU is intended to simplify various aspects related to accounting for income taxes, eliminates certain exceptions to the general principles in ASC Topic 740 related to intra-period tax allocation, simplifies when companies recognize deferred taxes in an interim period, and clarifies certain aspects of the current guidance to promote consistent application. This guidance effective for public entities for fiscal years beginning after December 15, 2020, and for interim period within those fiscal years, with early adoption permitted. The Company adopted the ASU provisions on January 1, 2021 and the adoption of the ASU provisions did not have a significant impact on the Company’s consolidated financial statements. In the year ended December 31, 2023, the Company adopted the following new accounting guidance: FASB ASU 2022-02, Financial Instruments - Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures, issued March 2022, eliminates the recognition and measurement guidance for troubled debt restructurings and requires enhanced disclosures about loan modifications for borrowers experiencing financial difficulty. This ASU also requires enhanced disclosure for loans that have been charged off. The ASU became effective January 1, 2023 under a prospective approach. The Company adopted the provisions to remove the recognition and measurement guidance for troubled debt restructurings and/or modify relevant disclosures in the “Loans” note to the consolidated financial statements. The requirement to include additional disclosures was adopted by the Company January 1, 2023. The additional disclosures did not affect the financial results upon adoption.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Issued Accounting Standards FASB ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, was issued March 2020. The ASU provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. For transactions that are modified because of reference rate reform and that meet certain scope guidance (i) modifications of loan agreements should be accounted for by prospectively adjusting the effective interest rate and the modification will be considered "minor" so that any existing unamortized origination fees/costs would carry forward and continue to be amortized and (ii) modifications of lease agreements should be accounted for as a continuation of the existing agreement with no reassessments of the lease classification and the discount rate or remeasurements of lease payments that otherwise would be required for modifications not accounted for as separate contracts. ASU 2020-04 also provides numerous optional expedients for derivative accounting. In December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848.” The ASU 2022-06 deferred the sunset date of ASU 2020-04 to December 2024. Once elected for a Topic or an Industry Subtopic within the Codification, the amendments in this ASU must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. The Company does not expect any material impact on its consolidated financial statements. FASB ASU 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions, was issued June 2022. The ASU clarifies the guidance in Topic 820 when measuring the fair value of an equity security subject to contractual restrictions that prohibit the sale of an equity security. Additionally, the ASU requires specific disclosures related to equity securities that are subject to contractual sale restrictions. The required disclosures include (1) the fair value of such equity securities reflected in the balance sheet, (2) the nature and remaining duration of the corresponding restrictions, and (3) any circumstances that could cause a lapse in the restrictions. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of this ASU on its consolidated financial statements. FASB ASU 2023-02, Investments – Equity Method and Joint Ventures (Topic 323):Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method, was issued March 2023. The ASU expands the use of the proportional amortization method of accounting, currently only available to investments in low-income housing tax credit structures, to equity investments in other tax credit structures that meet certain criteria. The ASU also requires additional disclosures for any tax credit program where the proportional amortization method is elected. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of this ASU on its consolidated financial statements.

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Use of Estimates, Policy [Policy Text Block]

Accounting Estimates. Certain accounting policies underlying the preparation of these financial statements require Management to make estimates, assumptions, and judgments that affect the amounts reported in the financial statements and accompanying notes. These estimates, assumptions, and judgments are based on information available as of the date of the financial statements; accordingly, as this information changes, the financial statements could reflect different estimates, assumptions, and judgments and as such have a greater possibility of producing results that could be materially different than originally reported. Estimates, assumptions, and judgments are necessary when assets and liabilities are required to be recorded at fair value, when a decline in fair value of an asset not carried on the financial statements at fair value warrants an impairment writedown or valuation reserve to be established, or when an asset or liability needs to be recorded contingent upon a future event. The allowance for credit losses accounting is an area requiring the most subjective or complex judgments, and as such could be most subject to revision as new information becomes available. A discussion of the factors affecting the accounting for the allowance for credit losses on loans is included in the following “Loans” and “Allowance for Credit Losses” sections. Carrying assets and liabilities at fair value inherently results in financial statement volatility. The fair values and the information used to record valuation adjustments for certain assets and liabilities are based either on quoted market prices or are provided by other third party sources, when available. The “Securities” section discusses the factors that may affect the valuation of the Company’s securities. Although the estimates contemplate current conditions actual results can change.

Consolidation, Policy [Policy Text Block]

Principles of Consolidation. The consolidated financial statements include the accounts of the Company and all the Company’s subsidiaries. Significant intercompany transactions have been eliminated in consolidation. The Company does not maintain or conduct transactions with any unconsolidated special purpose entities.

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash. Cash includes Due From Banks balances which are readily convertible to known amounts of cash and are generally 90 days or less from maturity at the time of initiation, presenting insignificant risk of changes in value due to interest rate changes.

Marketable Securities, Policy [Policy Text Block]

Equity Securities. Equity securities consist of marketable equity securities and mutual funds which are recorded at fair value. Unrealized gains and losses are included in net income. There were no equity securities at December 31, 2023 and December 31, 2022.

Debt Securities. Debt securities consist of the securities of government sponsored entities, states, counties, municipalities, corporations, agency and non-agency mortgage-backed securities, collateralized loan obligations and commercial paper. Securities transactions are recorded on a trade date basis. The Company classifies its debt securities in one of three categories: trading, available for sale or held to maturity. Trading securities are bought and held principally for the purpose of selling them in the near term. Trading securities are recorded at fair value with unrealized gains and losses included in net income. Held to maturity debt securities are those securities which the Company has the ability and intent to hold until maturity. Held to maturity debt securities are recorded at cost, adjusted for the amortization of premiums or accretion of discounts. Securities not included in trading or held to maturity are classified as available for sale debt securities. Available for sale debt securities are recorded at fair value. Unrealized gains and losses, net of the related tax effect, on available for sale debt securities are included in accumulated other comprehensive income. Accrued interest is recorded within other assets and reversed against interest income if it is not received.

The Company utilizes third-party sources to value its investment securities; securities individually valued using quoted prices in active markets are classified as Level 1 assets in the fair value hierarchy, and securities valued using quoted prices in active markets for similar securities (commonly referred to as “matrix” pricing) are classified as Level 2 assets in the fair value hierarchy. The Company validates the reliability of third-party provided values by comparing individual security pricing for securities between more than one third-party source. When third-party information is not available, valuation adjustments are estimated in good faith by Management and classified as Level 3 in the fair value hierarchy.

The Company follows the guidance issued by the Board of Governors of the Federal Reserve System, “Investing in Securities without Reliance on Nationally Recognized Statistical Rating Agencies” (SR 12-15) and other regulatory guidance when performing investment security pre-purchase analysis or evaluating investment securities for credit loss. Credit ratings issued by recognized rating agencies are considered in the Company’s analysis only as a guide to the historical default rate associated with similarly-rated bonds.

To the extent that debt securities in the held-to-maturity portfolio share common risk characteristics, estimated expected credit losses are calculated in a manner like that used for loans held for investment. That is, for pools of such securities with common risk characteristics, the historical lifetime probability of default and severity of loss in the event of default is derived or obtained from external sources and adjusted for the expected effects of reasonable and supportable forecasts over the expected lives of the securities on those historical credit losses. Expected credit loss on each security in the held-to-maturity portfolio that do not share common risk characteristics with any of the pools of debt securities is individually evaluated and a reserve for credit losses is established at the difference between the discounted value of the expected future cash flows, based on the original effective interest rate, and the recorded amortized cost basis of the security. For certain classes of debt securities, the bank considers the history of credit losses, current conditions and reasonable and supportable forecasts, which may indicate that the expectation that nonpayment of the amortized cost basis is or continues to be zero. Therefore, for those securities, the bank does not record expected credit losses.

Available for sale debt securities in unrealized loss positions are evaluated for credit related loss at least quarterly. For available for sale debt securities, a decline in fair value due to credit loss results in recording an allowance for credit losses to the extent the fair value is less than the amortized cost basis. Declines in fair value that have not been recorded through an allowance for credit losses, such as declines due to changes in market interest rates, are recorded through other comprehensive income, net of applicable taxes. Although these evaluations involve significant judgment, an unrealized loss in the fair value of a debt security is generally considered to not be related to credit when the fair value of the security is below the carrying value primarily due to changes in risk-free interest rates, there has not been significant deterioration in the financial condition of the issuer, and the Company does not intend to sell nor does it believe it will be required to sell the security before the recovery of its cost basis.

If the Company intends to sell a debt security or more likely than not will be required to sell the security before recovery of its amortized cost basis, the debt security is written down to its fair value and the write down is charged against the allowance for credit losses with any incremental loss reported in earnings.

Purchase premiums are amortized to the earliest call date and purchase discounts are amortized to maturity as an adjustment to yield using the effective interest method. Unamortized premiums, unaccreted discounts, and early payment premiums are recognized as a component of gain or loss on sale upon disposition of the related security. Interest and dividend income are recognized when earned. Realized gains and losses from the sale of available for sale debt securities are included in earnings using the specific identification method.

Equity Securities without Readily Determinable Fair Value [Policy Text Block]

Nonmarketable Equity Securities. Nonmarketable equity securities include securities that are not publicly traded, such as Visa Class B common stock, and securities acquired to meet regulatory requirements, such as Federal Reserve Bank stock, which are restricted. These restricted securities are accounted for under the cost method and are included in other assets. The Company reviews those assets accounted for under the cost method at least quarterly. The Company’s review typically includes an analysis of the facts and circumstances of each investment, the expectations for the investment’s cash flows and capital needs, the viability of its business model and any exit strategy. When the review indicates that impairment exists the asset value is reduced to fair value. The Company recognizes the estimated loss in noninterest income.

Financing Receivable [Policy Text Block]

Loans. Loans are stated at the principal amount outstanding, net of unearned discount and unamortized deferred fees and costs. Interest is accrued daily on the outstanding principal balances and included in other assets. Loans which are more than 90 days delinquent with respect to interest or principal, unless they are well secured and in the process of collection, and other loans on which full recovery of principal or interest is in doubt, are placed on nonaccrual status. Interest previously accrued on loans placed on nonaccrual status is charged against interest income. In addition, some loans secured by real estate and commercial loans to borrowers experiencing financial difficulties are placed on nonaccrual status even though the borrowers continue to repay the loans as scheduled. When the ability to fully collect nonaccrual loan principal is in doubt, payments received are applied against the principal balance of the loans on a cost-recovery method until such time as full collection of the remaining recorded balance is expected. Any additional interest payments received after that time are recorded as interest income on a cash basis. Nonaccrual loans are reinstated to accrual status when none of the loan’s principal and interest is past due and improvements in credit quality eliminate doubt as to the full collectability of both principal and interest, or the loan otherwise becomes well secured and in the process of collection. Certain consumer loans or auto receivables are charged off against the allowance for credit losses when they become 120 days past due.

Loans and Leases Receivable, Allowance for Loan Losses Policy [Policy Text Block]

Allowance for Credit Losses. The Company extends loans to commercial and consumer customers primarily in Northern and Central California. These lending activities expose the Company to the risk borrowers will default, causing loan losses. The Company’s lending activities are exposed to various qualitative risks. All loan segments are exposed to risks inherent in the economy and market conditions. Significant risk characteristics related to the commercial loan segment include the borrowers’ business performance and financial condition, and the value of collateral for secured loans. Significant risk characteristics related to the commercial real estate segment include the borrowers’ business performance and the value of properties collateralizing the loans. Significant risk characteristics related to the construction loan segment include the borrowers’ performance in successfully developing the real estate into the intended purpose and the value of the property collateralizing the loans. Significant risk characteristics related to the residential real estate segment include the borrowers’ financial wherewithal to service the mortgages and the value of the property collateralizing the loans. Significant risk characteristics related to the consumer loan segment include the financial condition of the borrowers and the value of collateral securing the loans.

The preparation of these financial statements requires Management to estimate the amount of expected losses over the expected contractual life of the Bank’s existing loan portfolio and establish an allowance for credit losses. Loan agreements generally include a maturity date, and the Company considers the contractual life of a loan agreement to extend from the date of origination to the contractual maturity date. In estimating credit losses, Management must exercise significant judgment in evaluating information deemed relevant. The amount of ultimate losses on the loan portfolio can vary from the estimated amounts. Management follows a systematic methodology to estimate loss potential in an effort to reduce the differences between estimated and actual losses.

The allowance for credit losses is established through provisions for credit losses charged to income. Losses on loans are charged to the allowance for credit losses when all or a portion of the recorded amount of a loan is deemed to be uncollectible. Recoveries of loans previously charged off are credited to the allowance when realized. The Company’s allowance for credit losses is maintained at a level considered adequate to provide for expected losses based on historical loss rates adjusted for current and expected conditions over a forecast period. These include conditions unique to individual borrowers, as well as overall credit loss experience, the amount of past due, nonperforming and classified loans, recommendations of regulatory authorities, prevailing economic conditions, or credit protection agreements and other factors.

Loans that share common risk characteristics are segregated into pools based on common characteristics, which is primarily determined by loan, borrower, or collateral type. Historical loss rates are determined for each pool. For consumer installment loans, primarily secured by automobiles, historical loss rates are determined using a vintage methodology, which tracks losses based on period of origination. For commercial, construction, and commercial real estate, historical loss rates are determined using an open pool methodology where losses are tracked over time for all loans included in the pool at the historical measurement date. Historical loss rates are adjusted for factors that are not reflected in the historical loss rates that are attributable to national or local economic or industry trends which have occurred but have not yet been recognized in past loan charge-off history, estimated losses based on management’s reasonable and supportable expectation of economic trends over a forecast horizon of up to two years, and other factors that impact credit loss expectations that are not reflected in the historical loss rates. Other factors include, but are not limited to, the effectiveness of the Company’s loan review system, adequacy of lending Management and staff, loan policies and procedures, problem loan trends, and concentrations of credit. At the end of the two-year forecast period loss rates revert immediately to the historical loss rates. The results of this analysis are applied to the amortized cost of the loans included within each pool.

Loans that do not share risk characteristics with other loans in the pools are evaluated individually. A loan is considered ‘collateral-dependent’ when the borrower is experiencing financial difficulty and repayment is expected to be provided substantially through the operation or sale of the collateral. A credit loss reserve for collateral-dependent loans is established at the difference between the amortized cost basis in the loan and the fair value of the underlying collateral adjusted for costs to sell. For other individually evaluated loans that are not collateral dependent, a credit loss reserve is established at the difference between the amortized cost basis in the loan and the present value of expected future cash flows discounted at the loan’s effective interest rate. The impact of an expected modification to be made to loans to borrowers experiencing financial difficulty is included in the allowance for credit losses when management determines such modification is likely.

Accrued interest is recorded in other assets and is excluded from the estimation of expected credit loss. Accrued interest is reversed through interest income when amounts are determined to be uncollectible, which generally occurs when the underlying receivable is placed on nonaccrual status or charged off.

Off-Balance-Sheet Credit Exposure, Policy [Policy Text Block]

Liability for Off-Balance Sheet Credit Exposures. Off-balance sheet credit exposures relate to letters of credit and unfunded loan commitments for commercial, construction and consumer loans. The Company maintains a separate allowance for credit losses from off-balance-sheet credit exposures, which is included within other liabilities on the consolidated statements of financial condition. Increases or reductions to the Company’s allowance for credit losses from off-balance sheet credit exposures are recorded in other expenses. Management estimates the amount of expected losses by estimating expected usage exposures that are not unconditionally cancellable by the Company and applying the loss factors used in the allowance for credit loss methodology to estimate the liability for credit losses related to unfunded commitments. No credit loss estimate is reported for off-balance-sheet credit exposures that are unconditionally cancellable by the Company or for undrawn amounts under such arrangements that may be drawn prior to the cancellation of the arrangement.

Nonrefundable fees and certain costs associated with originating or acquiring loans are deferred and amortized as an adjustment to interest income over the contractual loan lives. Upon prepayment, unamortized loan fees, net of costs, are immediately recognized in interest income. Other fees, including those collected upon principal prepayments, are included in interest income when received. Loans held for sale are identified upon origination and are reported at the lower of cost or market value on an aggregate loan basis.

Financing Receivable, Real Estate Acquired Through Foreclosure [Policy Text Block]

Other Real Estate Owned. Other real estate owned is comprised of property acquired through foreclosure proceedings, acceptances of deeds-in-lieu of foreclosure and, if applicable, vacated bank properties. Losses recognized at the time of acquiring property in full or partial satisfaction of debt are charged against the allowance for credit losses. Other real estate owned is recorded at the fair value of the collateral, generally based upon an independent property appraisal, less estimated disposition costs. Losses incurred subsequent to acquisition due to any decline in annual independent property appraisals are recognized as noninterest expense. Routine holding costs, such as property taxes, insurance and maintenance, and losses from sales and dispositions, are recognized as noninterest expense.

Property, Plant and Equipment, Policy [Policy Text Block]

Premises and Equipment. Premises and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is computed substantially on the straight-line method over the estimated useful life of each type of asset. Estimated useful lives of premises and equipment range from 20 to 50 years and from 3 to 20 years, respectively. Leasehold improvements are amortized over the terms of the lease or their estimated useful life, whichever is shorter.

Revenue from Contract with Customer [Policy Text Block]

Revenue Recognition. The Company recognizes revenue as it is earned based on contractual terms, as transactions occur, or as services are provided and collectability is reasonably assured. In certain circumstances, noninterest income is reported net of associated expenses that are directly related to variable volume-based sales or revenue sharing arrangements or when the Company acts on an agency basis for others.

Life Insurance Cash Surrender Value [Policy Text Block]

Life Insurance Cash Surrender Value. The Company has purchased life insurance policies on certain directors and officers as well as acquired such assets as part of the acquisition of other banks. Company owned life insurance is recorded at the amount that can be realized under the insurance contract at the balance sheet date, which is the cash surrender value adjusted for other charges or other amounts due that are probable at settlement. These assets are included in other assets on the consolidated balance sheets.

Goodwill and Intangible Assets, Policy [Policy Text Block]

Intangible Assets. Intangible assets are comprised of goodwill, core deposit intangibles and other identifiable intangibles acquired in business combinations. Intangible assets with finite useful lives are amortized on an accelerated basis over their respective estimated useful lives not exceeding 15 years. Intangible assets with a finite useful life are reviewed at least annually for impairment. Any goodwill and any intangible asset acquired in a business combination determined to have an indefinite useful life is not amortized and is reviewed at least annually for impairment. If management determines, based on a qualitative review of events and circumstances, that it is more likely than not that the carrying value of the intangible asset will not be realized, an impairment test is performed to determine whether the asset’s fair value is less than the carrying amount of the asset.

Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]

Impairment of Long-Lived Assets. The Company reviews its long-lived and certain intangible assets for impairment whenever events or changes indicate that the carrying amount of an asset may not be recoverable. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.

Income Tax, Policy [Policy Text Block]

Income Taxes. The Company and its subsidiaries file consolidated tax returns. The Company accounts for income taxes in accordance with FASB ASC 740, Income Taxes, resulting in two components of income tax expense: current and deferred. Current income tax expense approximates taxes to be paid or refunded for the current period. The Company determines deferred income taxes using the balance sheet method. Under this method, the net deferred tax asset or liability is based on the tax effects of the differences between the book and tax bases of assets and liabilities, and recognizes enacted changes in tax rates and laws in the period in which they occur. Deferred income tax expense results from changes in deferred tax assets and liabilities between periods. Deferred tax assets are recognized subject to Management’s judgment that realization is more likely than not. A tax position that meets the more likely than not recognition threshold is measured to determine the amount of benefit to recognize. The tax position is measured at the largest amount of benefit that is greater than fifty percent likely of being realized upon settlement. Interest and penalties are recognized as a component of income tax expense.

Share-Based Payment Arrangement [Policy Text Block]

Stock-Based Compensation. The Company applies FASB ASC 718 – Compensation – Stock Compensation, to account for stock based awards granted to employees using the fair value method. The Company recognizes compensation expense for restricted performance share grants over the relevant attribution period. Restricted performance share grants have no exercise price, therefore, the intrinsic value is measured using an estimated per share price at the vesting date for each restricted performance share. The estimated per share price is adjusted during the attribution period to reflect actual stock price performance. The Company’s obligation for unvested outstanding restricted performance share grants is classified as a liability until the vesting date due to a cash settlement feature, at which time the issued shares become classified as shareholders’ equity.

Fiduciary [Policy Text Block]

Other. Securities and other property held by the Bank in a fiduciary or agency capacity are not included in the financial statements since such items are not assets of the Company or its subsidiaries.

Currently Adopted Accounting Pronouncements [Policy Text Block]

Recently Adopted Accounting Standards

In the year ended December 31, 2021, the Company adopted the following new accounting guidance:

FASB ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, was issued December 2019. The ASU is intended to simplify various aspects related to accounting for income taxes, eliminates certain exceptions to the general principles in ASC Topic 740 related to intra-period tax allocation, simplifies when companies recognize deferred taxes in an interim period, and clarifies certain aspects of the current guidance to promote consistent application. This guidance effective for public entities for fiscal years beginning after December 15, 2020, and for interim period within those fiscal years, with early adoption permitted. The Company adopted the ASU provisions on January 1, 2021 and the adoption of the ASU provisions did not have a significant impact on the Company’s consolidated financial statements.

In the year ended December 31, 2023, the Company adopted the following new accounting guidance:

FASB ASU 2022-02, Financial Instruments - Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures, issued March 2022, eliminates the recognition and measurement guidance for troubled debt restructurings and requires enhanced disclosures about loan modifications for borrowers experiencing financial difficulty. This ASU also requires enhanced disclosure for loans that have been charged off. The ASU became effective January 1, 2023 under a prospective approach. The Company adopted the provisions to remove the recognition and measurement guidance for troubled debt restructurings and/or modify relevant disclosures in the “Loans” note to the consolidated financial statements. The requirement to include additional disclosures was adopted by the Company January 1, 2023. The additional disclosures did not affect the financial results upon adoption.

New Accounting Pronouncements, Policy [Policy Text Block]

Recently Issued Accounting Standards

FASB ASU 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting, was issued March 2020. The ASU provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. For transactions that are modified because of reference rate reform and that meet certain scope guidance (i) modifications of loan agreements should be accounted for by prospectively adjusting the effective interest rate and the modification will be considered "minor" so that any existing unamortized origination fees/costs would carry forward and continue to be amortized and (ii) modifications of lease agreements should be accounted for as a continuation of the existing agreement with no reassessments of the lease classification and the discount rate or remeasurements of lease payments that otherwise would be required for modifications not accounted for as separate contracts. ASU 2020-04 also provides numerous optional expedients for derivative accounting. In December 2022, the FASB issued ASU 2022-06, Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848.” The ASU 2022-06 deferred the sunset date of ASU 2020-04 to December 2024. Once elected for a Topic or an Industry Subtopic within the Codification, the amendments in this ASU must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. The Company does not expect any material impact on its consolidated financial statements.

FASB ASU 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions, was issued June 2022. The ASU clarifies the guidance in Topic 820 when measuring the fair value of an equity security subject to contractual restrictions that prohibit the sale of an equity security. Additionally, the ASU requires specific disclosures related to equity securities that are subject to contractual sale restrictions. The required disclosures include (1) the fair value of such equity securities reflected in the balance sheet, (2) the nature and remaining duration of the corresponding restrictions, and (3) any circumstances that could cause a lapse in the restrictions. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of this ASU on its consolidated financial statements.

FASB ASU 2023-02, Investments – Equity Method and Joint Ventures (Topic 323):Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method, was issued March 2023. The ASU expands the use of the proportional amortization method of accounting, currently only available to investments in low-income housing tax credit structures, to equity investments in other tax credit structures that meet certain criteria. The ASU also requires additional disclosures for any tax credit program where the proportional amortization method is elected. The ASU is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. The Company is currently evaluating the impact of this ASU on its consolidated financial statements.