Note 1 - Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2020
Notes to Financial Statements
Significant Accounting Policies [Text Block]	Note 1. Summary of Significant Accounting Policies Nature of Business — Wilson Bank Holding Company (the “Company”) is a bank holding company whose primary business is conducted by its wholly-owned subsidiary, Wilson Bank & Trust (the “Bank”). The Bank is a commercial bank headquartered in Lebanon, Tennessee. The Bank provides a full range of banking services in its primary market areas of Wilson, Davidson, Rutherford, Trousdale, Sumner, Dekalb, Putnam, Smith, and Williamson Counties, Tennessee. Basis of Presentation — The accompanying unaudited, consolidated financial statements have been prepared in accordance with instructions to Form 10-Q and therefore do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, and cash flows in conformity with U.S. generally accepted accounting principles. All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods covered by the report have been included. The accompanying unaudited consolidated financial statements should be read in conjunction with the Company’s consolidated audited financial statements and related notes appearing in the Company's Annual Report on Form 10-K for the year ended December 31, 2019. These consolidated financial statements include the accounts of the Company and the Bank. Significant intercompany transactions and accounts are eliminated in consolidation. Use of Estimates — The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the balance sheet date and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term include the determination of the allowance for loan losses, the valuation of deferred tax assets, determination of any impairment of goodwill or other intangibles, other-than-temporary impairment of securities, the valuation of other real estate, and the fair value of financial instruments. These financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2019. There have been no significant changes to the Company’s significant accounting policies as disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019. Loans — Loans are reported at their outstanding principal balances less unearned income, the allowance for loan losses and any deferred fees or costs on originated loans. Interest income on loans is accrued based on the principal balance outstanding. Loan origination fees, net of certain loan origination costs, are deferred and recognized as an adjustment to the related loan yield using a method which approximates the interest method. Loans are charged off when management believes that the full collectability of the loan is unlikely. As such, a loan may be partially charged-off after a “confirming event” has occurred which serves to validate that full repayment pursuant to the terms of the loan is unlikely. Loans are placed on nonaccrual status when there is a significant deterioration in the financial condition of the borrower, which often is determined when the principal or interest on the loan is more than 90 days past due, unless the loan is both well-secured and in the process of collection. Generally, all interest accrued but not collected for loans that are placed on nonaccrual status, is reversed against current income. Interest income is subsequently recognized only to the extent cash payments are received while the loan is classified as nonaccrual, but interest income recognition is reviewed on a case-by-case basis. A nonaccrual loan is returned to accruing status once the loan has been brought current and collection is reasonably assured or the loan has been “well-secured” through other techniques. Past due status is determined based on the contractual due date per the underlying loan agreement. All loans that are placed on nonaccrual are further analyzed to determine if they should be classified as impaired loans. At December 31, 2019 and March 31, 2020, there were no loans classified as nonaccrual that were not also deemed to be impaired except for those loans not individually evaluated for impairment as described below. A loan is considered to be impaired when it is probable the Company will be unable to collect all principal and interest payments due in accordance with the contractual terms of the loan. This determination is made using one or more of a variety of techniques, which include a review of the borrower’s financial condition, debt-service coverage ratios, global cash flow analysis, guarantor support, other loan file information, meetings with borrowers, inspection or reappraisal of collateral and/or consultation with legal counsel as well as results of reviews of other similar industry credits (e.g. builder loans, development loans, church loans, etc). Loans with an identified weakness and principal balance of $500,000 or more are subject to individual identification for impairment. Individually identified impaired loans are measured based on the present value of expected payments using the loan’s original effective rate as the discount rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent. If the recorded investment in the impaired loan exceeds the measure of fair value, a specific valuation allowance is established as a component of the allowance for loan losses or, in the case of collateral dependent loans, the excess may be charged off. Changes to the valuation allowance are recorded as a component of the provision for loan losses. Any subsequent adjustments to present value calculations for impaired loan valuations as a result of the passage of time, such as changes in the anticipated payback period for repayment, are recorded as a component of the provision for loan losses. For loans less than $500,000, the Company assigns a valuation allowance to these loans utilizing an allocation rate equal to the allocation rate calculated for non-impaired loans of a similar type. Allowance for Loan Losses — The allowance for loan losses is maintained at a level that management believes to be adequate to absorb probable losses in the loan portfolio. Loan losses are charged against the allowance when they are known. Subsequent recoveries are credited to the allowance. Management’s determination of the adequacy of the allowance is based on an evaluation of the portfolio, current economic conditions, volume, growth, composition of the loan portfolio, homogeneous pools of loans, risk ratings of specific loans, historical loan loss factors, loss experience of various loan segments, identified impaired loans and other factors related to the portfolio. This evaluation is performed quarterly and is inherently subjective, as it requires material estimates that are susceptible to significant change including the amounts and timing of future cash flows expected to be received on any impaired loans. In assessing the adequacy of the allowance, we also consider the results of our ongoing independent loan review process. We undertake this process both to ascertain whether there are loans in the portfolio whose credit quality has weakened over time and to assist in our overall evaluation of the risk characteristics of the entire loan portfolio. Our loan review process includes the judgment of management, independent loan reviewers, and reviews that may have been conducted by third-party reviewers. We incorporate relevant loan review results in the loan impairment determination. In addition, regulatory agencies, as an integral part of their examination process, will periodically review the Company’s allowance for loan losses, and may require the Company to record adjustments to the allowance based on their judgment about information available to them at the time of their examinations. Recently Issued Accounting Pronouncements ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” ASU 2016-13 along with several other subsequent codification updates related to accounting for credit losses, requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts and requires enhanced disclosures related to the significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an organization’s portfolio. In addition, ASU 2016-13 amends the accounting for credit losses on available-for-sale debt securities and purchased financial assets with credit deterioration. ASU 2016-13 was originally to become effective for us on January 1, 2020. On March 27, 2020, President Trump signed into law the Coronavirus Aid, Relief and Economic Security ("CARES") Act. The law contains several provisions, among them, it gives lenders, including the Company, the option to defer the implementation of ASU 2016-13, which is known as the Current Expected Credit Losses (CECL) standard, until 60 days after the declaration of the end of the public health emergency related to the COVID-19 pandemic or December 31, 2020, whichever comes first. In addition, the Securities and Exchange Commission (SEC) staff has stated that opting to delay the implementation of CECL shall be considered to be in accordance with generally accepted accounting principles. As a result, the Company has elected to delay implementation of CECL. We currently believe the adoption of ASU 2016-13 would have resulted in approximately a 4-6 % increase in our allowance for loan losses as of January 1, 2020. That expected increase is a result of changing from an “incurred loss” model, which encompasses allowances for current known and inherent losses within the portfolio, to an “expected loss” model, which encompasses allowances for losses expected to be incurred over the life of the portfolio. As of March 31, 2020, we currently believe the adoption of ASU 2016-13 would have resulted in approximately a 4-6 % increase in our allowance for loan losses. Prior to the CARES Act being signed and the Company’s decision to delay the implementation of CECL, the Company was completing its CECL implementation plan with a cross-functional working group, under the direction of the Chief Credit Officer along with our Chief Financial Officer. The working group also included individuals from various functional areas including credit, risk management, accounting and information technology, among others. The Company’s implementation plan included assessment and documentation of processes, internal controls and data sources; model development, documentation and validation; and system configuration, among other things. The Company contracted with a third-party vendor to assist it in the implementation of CECL. As we are currently finalizing the execution of our implementation controls and processes, the ultimate impact of the adoption of ASU 2016-13 could differ from our current expectation. Furthermore, ASU 2016-13 will necessitate that we establish an allowance for expected credit losses for available-for-sale securities and other financial assets and it also applies to off-balance sheet credit exposure like loan commitments and other investments; however, we do not expect these allowances to be significant. The adoption of ASU 2016-13 is not expected to have a significant impact on our regulatory capital ratios. ASU 2017-04, “Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment.” ASU 2017-04 eliminates Step 2 from the goodwill impairment test which required entities to compute the implied fair value of goodwill. Under ASU 2017-04, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. ASU 2017-04 became effective for us on January 1, 2020, and did not have a significant impact on our financial statements. ASU 2018-13, "Fair Value Measurement (Topic 820) - Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement." ASU 2018-13 modifies the disclosure requirements on fair value measurements in Topic 820. The amendments in this update remove disclosures that no longer are considered cost beneficial, modify/clarify the specific requirements of certain disclosures, and add disclosure requirements identified as relevant. ASU 2018-13 became effective for us on January 1, 2020 and did not have a significant impact on our financial statements.

Note 1 - Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2020

Significant Accounting Policies [Text Block]

Note 1. Summary of Significant Accounting Policies

Nature of Business — Wilson Bank Holding Company (the “Company”) is a bank holding company whose primary business is conducted by its wholly-owned subsidiary, Wilson Bank & Trust (the “Bank”). The Bank is a commercial bank headquartered in Lebanon, Tennessee. The Bank provides a full range of banking services in its primary market areas of Wilson, Davidson, Rutherford, Trousdale, Sumner, Dekalb, Putnam, Smith, and Williamson Counties, Tennessee.

Basis of Presentation — The accompanying unaudited, consolidated financial statements have been prepared in accordance with instructions to Form 10-Q and therefore do not include all information and footnotes necessary for a fair presentation of financial position, results of operations, and cash flows in conformity with U.S. generally accepted accounting principles. All adjustments consisting of normally recurring accruals that, in the opinion of management, are necessary for a fair presentation of the financial position and results of operations for the periods covered by the report have been included. The accompanying unaudited consolidated financial statements should be read in conjunction with the Company’s consolidated audited financial statements and related notes appearing in the Company's Annual Report on Form 10-K for the year ended December 31, 2019.

These consolidated financial statements include the accounts of the Company and the Bank. Significant intercompany transactions and accounts are eliminated in consolidation.

Use of Estimates — The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the balance sheet date and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Material estimates that are particularly susceptible to significant change in the near term include the determination of the allowance for loan losses, the valuation of deferred tax assets, determination of any impairment of goodwill or other intangibles, other-than-temporary impairment of securities, the valuation of other real estate, and the fair value of financial instruments. These financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2019. There have been no significant changes to the Company’s significant accounting policies as disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019.

Loans — Loans are reported at their outstanding principal balances less unearned income, the allowance for loan losses and any deferred fees or costs on originated loans. Interest income on loans is accrued based on the principal balance outstanding. Loan origination fees, net of certain loan origination costs, are deferred and recognized as an adjustment to the related loan yield using a method which approximates the interest method.

Loans are charged off when management believes that the full collectability of the loan is unlikely. As such, a loan may be partially charged-off after a “confirming event” has occurred which serves to validate that full repayment pursuant to the terms of the loan is unlikely.

Loans are placed on nonaccrual status when there is a significant deterioration in the financial condition of the borrower, which often is determined when the principal or interest on the loan is more than 90 days past due, unless the loan is both well-secured and in the process of collection. Generally, all interest accrued but not collected for loans that are placed on nonaccrual status, is reversed against current income. Interest income is subsequently recognized only to the extent cash payments are received while the loan is classified as nonaccrual, but interest income recognition is reviewed on a case-by-case basis. A nonaccrual loan is returned to accruing status once the loan has been brought current and collection is reasonably assured or the loan has been “well-secured” through other techniques. Past due status is determined based on the contractual due date per the underlying loan agreement.

All loans that are placed on nonaccrual are further analyzed to determine if they should be classified as impaired loans. At December 31, 2019 and March 31, 2020, there were no loans classified as nonaccrual that were not also deemed to be impaired except for those loans not individually evaluated for impairment as described below. A loan is considered to be impaired when it is probable the Company will be unable to collect all principal and interest payments due in accordance with the contractual terms of the loan. This determination is made using one or more of a variety of techniques, which include a review of the borrower’s financial condition, debt-service coverage ratios, global cash flow analysis, guarantor support, other loan file information, meetings with borrowers, inspection or reappraisal of collateral and/or consultation with legal counsel as well as results of reviews of other similar industry credits (e.g. builder loans, development loans, church loans, etc). Loans with an identified weakness and principal balance of $500,000 or more are subject to individual identification for impairment. Individually identified impaired loans are measured based on the present value of expected payments using the loan’s original effective rate as the discount rate, the loan’s observable market price, or the fair value of the collateral if the loan is collateral dependent. If the recorded investment in the impaired loan exceeds the measure of fair value, a specific valuation allowance is established as a component of the allowance for loan losses or, in the case of collateral dependent loans, the excess may be charged off. Changes to the valuation allowance are recorded as a component of the provision for loan losses. Any subsequent adjustments to present value calculations for impaired loan valuations as a result of the passage of time, such as changes in the anticipated payback period for repayment, are recorded as a component of the provision for loan losses. For loans less than $500,000, the Company assigns a valuation allowance to these loans utilizing an allocation rate equal to the allocation rate calculated for non-impaired loans of a similar type.

Allowance for Loan Losses — The allowance for loan losses is maintained at a level that management believes to be adequate to absorb probable losses in the loan portfolio. Loan losses are charged against the allowance when they are known. Subsequent recoveries are credited to the allowance. Management’s determination of the adequacy of the allowance is based on an evaluation of the portfolio, current economic conditions, volume, growth, composition of the loan portfolio, homogeneous pools of loans, risk ratings of specific loans, historical loan loss factors, loss experience of various loan segments, identified impaired loans and other factors related to the portfolio. This evaluation is performed quarterly and is inherently subjective, as it requires material estimates that are susceptible to significant change including the amounts and timing of future cash flows expected to be received on any impaired loans.

In assessing the adequacy of the allowance, we also consider the results of our ongoing independent loan review process. We undertake this process both to ascertain whether there are loans in the portfolio whose credit quality has weakened over time and to assist in our overall evaluation of the risk characteristics of the entire loan portfolio. Our loan review process includes the judgment of management, independent loan reviewers, and reviews that may have been conducted by third-party reviewers. We incorporate relevant loan review results in the loan impairment determination. In addition, regulatory agencies, as an integral part of their examination process, will periodically review the Company’s allowance for loan losses, and may require the Company to record adjustments to the allowance based on their judgment about information available to them at the time of their examinations.

Recently Issued Accounting Pronouncements

ASU 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” ASU 2016-13 along with several other subsequent codification updates related to accounting for credit losses, requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts and requires enhanced disclosures related to the significant estimates and judgments used in estimating credit losses, as well as the credit quality and underwriting standards of an organization’s portfolio. In addition, ASU 2016-13 amends the accounting for credit losses on available-for-sale debt securities and purchased financial assets with credit deterioration.

ASU 2016-13 was originally to become effective for us on January 1, 2020. On March 27, 2020, President Trump signed into law the Coronavirus Aid, Relief and Economic Security ("CARES") Act. The law contains several provisions, among them, it gives lenders, including the Company, the option to defer the implementation of ASU 2016-13, which is known as the Current Expected Credit Losses (CECL) standard, until 60 days after the declaration of the end of the public health emergency related to the COVID-19 pandemic or December 31, 2020, whichever comes first. In addition, the Securities and Exchange Commission (SEC) staff has stated that opting to delay the implementation of CECL shall be considered to be in accordance with generally accepted accounting principles. As a result, the Company has elected to delay implementation of CECL.

We currently believe the adoption of ASU 2016-13 would have resulted in approximately a 4-6 % increase in our allowance for loan losses as of January 1, 2020. That expected increase is a result of changing from an “incurred loss” model, which encompasses allowances for current known and inherent losses within the portfolio, to an “expected loss” model, which encompasses allowances for losses expected to be incurred over the life of the portfolio. As of March 31, 2020, we currently believe the adoption of ASU 2016-13 would have resulted in approximately a 4-6 % increase in our allowance for loan losses.

Prior to the CARES Act being signed and the Company’s decision to delay the implementation of CECL, the Company was completing its CECL implementation plan with a cross-functional working group, under the direction of the Chief Credit Officer along with our Chief Financial Officer. The working group also included individuals from various functional areas including credit, risk management, accounting and information technology, among others. The Company’s implementation plan included assessment and documentation of processes, internal controls and data sources; model development, documentation and validation; and system configuration, among other things. The Company contracted with a third-party vendor to assist it in the implementation of CECL. As we are currently finalizing the execution of our implementation controls and processes, the ultimate impact of the adoption of ASU 2016-13 could differ from our current expectation. Furthermore, ASU 2016-13 will necessitate that we establish an allowance for expected credit losses for available-for-sale securities and other financial assets and it also applies to off-balance sheet credit exposure like loan commitments and other investments; however, we do not expect these allowances to be significant. The adoption of ASU 2016-13 is not expected to have a significant impact on our regulatory capital ratios.

ASU 2017-04, “Intangibles - Goodwill and Other (Topic 350) - Simplifying the Test for Goodwill Impairment.” ASU 2017-04 eliminates Step 2 from the goodwill impairment test which required entities to compute the implied fair value of goodwill. Under ASU 2017-04, an entity should perform its annual, or interim, goodwill impairment test by comparing the fair value of a reporting unit with its carrying amount. An entity should recognize an impairment charge for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. ASU 2017-04 became effective for us on January 1, 2020, and did not have a significant impact on our financial statements.

ASU 2018-13, "Fair Value Measurement (Topic 820) - Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement." ASU 2018-13 modifies the disclosure requirements on fair value measurements in Topic 820. The amendments in this update remove disclosures that no longer are considered cost beneficial, modify/clarify the specific requirements of certain disclosures, and add disclosure requirements identified as relevant. ASU 2018-13 became effective for us on January 1, 2020 and did not have a significant impact on our financial statements.