Summary of Significant Accounting Policies	12 Months Ended
Dec. 31, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of Operations Commerce Bancshares, Inc. and its subsidiaries (the Company) conducts its principal activities from approximately 320 branch and ATM locations throughout Missouri, Illinois, Kansas, Oklahoma and Colorado. Principal activities include retail and commercial banking, investment management, securities brokerage, mortgage banking, credit related insurance and private equity investment activities. The Company also maintains commercial banking offices in Dallas, Houston, Cincinnati, Nashville, Des Moines, Indianapolis, and Grand Rapids. Basis of Presentation The Company follows accounting principles generally accepted in the United States of America (GAAP) and reporting practices applicable to the banking industry. The preparation of financial statements under GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and notes. These estimates are based on information available to management at the time the estimates are made. While the consolidated financial statements reflect management’s best estimates and judgments, actual results could differ from those estimates. The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries (after elimination of all material intercompany balances and transactions). Certain prior year amounts have been reclassified to conform to the current year presentation. Such reclassifications had no effect on net income or total assets. Management has evaluated subsequent events for potential recognition or disclosure through the date these consolidated financial statements were issued. The Company, in the normal course of business, engages in a variety of activities that involve variable interest entities (VIEs). A VIE is a legal entity that lacks equity investors or whose equity investors do not have a controlling financial interest in the entity through their equity investments. However, an enterprise is deemed to have a controlling financial interest and is the primary beneficiary of a VIE if it has both the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. An enterprise that is the primary beneficiary must consolidate the VIE. The Company’s interests in VIEs are evaluated to determine if the Company is the primary beneficiary both at inception and when there is a change in circumstances that requires a reconsideration. The Company is considered to be the primary beneficiary in a rabbi trust related to a deferred compensation plan offered to certain employees. The assets and liabilities of this trust, which are included in the accompanying consolidated balance sheets, are not significant. The Company also has variable interests in certain entities in which it is not the primary beneficiary. These entities are not consolidated. These interests include affordable housing limited partnership interests, holdings in its investment portfolio of various asset and mortgage-backed bonds that are issued by securitization trusts, and managed discretionary trust assets that are not included in the accompanying consolidated balance sheets. Cash, Cash Equivalents and Restricted Cash In the accompanying consolidated statements of cash flows, cash and cash equivalents include “Cash and due from banks”, “Federal funds sold and short-term securities purchased under agreements to resell”, and “Interest earning deposits with banks” as segregated in the accompanying consolidated balance sheets. Restricted cash is comprised of cash collateral on deposit with another financial institution to secure interest rate swap transactions. Restricted cash is included in other assets in the consolidated balance sheets and totaled $8.2 million and $12.5 million at December 31, 2018 and 2017, respectively. Regulations of the Federal Reserve System require cash balances to be maintained at the Federal Reserve Bank, based on certain deposit levels. The minimum reserve requirement for the Bank at December 31, 2018 totaled $228.3 million. Other interest earning cash balances held at the Federal Reserve Bank totaled $689.9 million. Loans and Related Earnings Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at their outstanding principal balances, net of undisbursed loan proceeds, the allowance for loan losses, and any deferred fees and costs on originated loans. Origination fee income received on loans and amounts representing the estimated direct costs of origination are deferred and amortized to interest income over the life of the loan using the interest method. Interest on loans is accrued based upon the principal amount outstanding. Interest income is recognized primarily on the level yield method. Loan and commitment fees, net of costs, are deferred and recognized in income over the term of the loan or commitment as an adjustment of yield. Annual fees charged on credit card loans are capitalized to principal and amortized over 12 months to loan fees and sales. Other credit card fees, such as cash advance fees and late payment fees, are recognized in income as an adjustment of yield when charged to the cardholder’s account. Non-Accrual Loans Loans are placed on non-accrual status when management does not expect to collect payments consistent with acceptable and agreed upon terms of repayment. Business, construction real estate, business real estate, and personal real estate loans that are contractually 90 days past due as to principal and/or interest payments are generally placed on non-accrual, unless they are both well-secured and in the process of collection. Consumer, revolving home equity and credit card loans are exempt under regulatory rules from being classified as non-accrual. When a loan is placed on non-accrual status, any interest previously accrued but not collected is reversed against current income, and the loan is charged off to the extent uncollectible. Principal and interest payments received on non-accrual loans are generally applied to principal. Interest is included in income only after all previous loan charge-offs have been recovered and is recorded only as received. The loan is returned to accrual status only when the borrower has brought all past due principal and interest payments current, and, in the opinion of management, the borrower has demonstrated the ability to make future payments of principal and interest as scheduled. A six month history of sustained payment performance is generally required before reinstatement of accrual status. Troubled Debt Restructurings A loan is accounted for as a troubled debt restructuring if the Company, for economic or legal reasons related to the borrowers’ financial difficulties, grants a concession to the borrower that it would not otherwise consider. A troubled debt restructuring typically involves (1) modification of terms such as a reduction of the stated interest rate, loan principal, or accrued interest, (2) a loan renewal at a stated interest rate lower than the current market rate for a new loan with similar risk, or (3) debt that was not reaffirmed in bankruptcy. Business, business real estate, construction real estate and personal real estate troubled debt restructurings with impairment charges are placed on non-accrual status. The Company measures the impairment loss of a troubled debt restructuring in the same manner as described below. Troubled debt restructurings which are performing under their contractual terms continue to accrue interest which is recognized in current earnings. Impaired Loans Loans are evaluated regularly by management for impairment. Included in impaired loans are all non-accrual loans, as well as loans that have been classified as troubled debt restructurings. Once a loan has been identified as impaired, impairment is measured based on either the present value of the expected future cash flows at the loan’s initial effective interest rate or the fair value of the collateral if collateral dependent. Factors considered in determining impairment include delinquency status, cash flow analysis, credit analysis, and collateral value and availability. Loans Held For Sale Loans held for sale include student loans and certain fixed rate residential mortgage loans. These loans are typically classified as held for sale upon origination based upon management's intent to sell the production of these loans. The student loans are carried at the lower of aggregate cost or fair value, and their fair value is determined based on sale contract prices. The mortgage loans are carried at fair value under the elected fair value option. Their fair value is based on secondary market prices for loans with similar characteristics, including an adjustment for embedded servicing value. Changes in fair value and gains and losses on sales are included in loan fees and sales. Deferred fees and costs related to these loans are not amortized but are recognized as part of the cost basis of the loan at the time it is sold. Interest income related to loans held for sale is accrued based on the principal amount outstanding and the loan's contractual interest rate. Occasionally, other types of loans may be classified as held for sale in order to manage credit concentration. These loans are carried at the lower of cost or fair value with gains and losses on sales recognized in loan fees and sales. Allowance/Provision for Loan Losses The allowance for loan losses is maintained at a level believed to be appropriate by management to provide for probable loan losses inherent in the portfolio as of the balance sheet date, including losses on known or anticipated problem loans as well as for loans which are not currently known to require specific allowances. Management has established a process to determine the amount of the allowance for loan losses which assesses the risks and losses inherent in its portfolio. Business, construction real estate and business real estate loans are normally larger and more complex, and their collection rates are harder to predict. These loans are more likely to be collateral dependent and are allocated a larger reserve, due to their potential volatility. Personal real estate, credit card, consumer and revolving home equity loans are individually smaller and perform in a more homogenous manner, making loss estimates more predictable. Management’s process provides an allowance consisting of a specific allowance component based on certain individually evaluated loans and a general component based on estimates of reserves needed for pools of loans. Loans subject to individual evaluation generally consist of business, construction real estate, business real estate and personal real estate loans on non-accrual status. These impaired loans are evaluated individually for the impairment of repayment potential and collateral adequacy. Other impaired loans identified as performing troubled debt restructurings are collectively evaluated because they have similar risk characteristics. Loans which have not been identified as impaired are segregated by loan type and sub-type and are collectively evaluated. Reserves calculated for these loan pools are estimated using a consistent methodology that considers historical loan loss experience by loan type, loss emergence periods, delinquencies, current economic factors, loan risk ratings and industry concentrations. The Company’s estimate of the allowance for loan losses and the corresponding provision for loan losses is based on various judgments and assumptions made by management. The amount of the allowance for loan losses is influenced by several qualitative factors which include collateral valuation, evaluation of performance and status, current loan portfolio composition and characteristics, trends in delinquencies, portfolio risk ratings, levels of non-performing assets, and prevailing regional and national economic and business conditions. The estimates, appraisals, evaluations, and cash flows utilized by management may be subject to frequent adjustments due to changing economic prospects of borrowers or properties. These estimates are reviewed periodically and adjustments, if necessary, are recorded in the provision for loan losses in the periods in which they become known. Loans, or portions of loans, are charged off to the extent deemed uncollectible. Loan charge-offs reduce the allowance for loan losses, and recoveries of loans previously charged off are added back to the allowance. Business, business real estate, construction real estate and personal real estate loans are generally charged down to estimated collectible balances when they are placed on non-accrual status. Consumer loans and related accrued interest are normally charged down to the fair value of related collateral (or are charged off in full if no collateral) once the loans are more than 120 days delinquent. Credit card loans are charged off against the allowance for loan losses when the receivable is more than 180 days past due. The interest and fee income previously capitalized but not collected on credit card charge-offs is reversed against interest income. Operating, Direct Financing and Sales Type Leases The net investment in direct financing and sales type leases is included in loans on the Company’s consolidated balance sheets and consists of the present values of the sum of the future minimum lease payments and estimated residual value of the leased asset. Revenue consists of interest earned on the net investment and is recognized over the lease term as a constant percentage return thereon. The net investment in operating leases is included in other assets on the Company’s consolidated balance sheets. It is carried at cost, less the amount depreciated to date. Depreciation is recognized on a straight-line basis over the lease term to the estimated residual value. Operating lease revenue consists of the contractual lease payments and is recognized over the lease term in other non-interest income. Estimated residual values are established at lease inception utilizing contract terms, past customer experience, and general market data and are reviewed and adjusted, if necessary, on an annual basis. Investments in Debt and Equity Securities The majority of the Company's investment portfolio is comprised of debt securities which are classified as available for sale. From time to time, the Company sells securities and utilizes the proceeds to reduce borrowings, fund loan growth, or modify its interest rate profile. Securities classified as available for sale are carried at fair value. Changes in fair value, excluding certain losses associated with other-than-temporary impairment (OTTI), are reported in other comprehensive income (loss), a component of stockholders’ equity. Securities are periodically evaluated for OTTI in accordance with guidance provided in ASC 320-10-35. For securities with OTTI, the entire loss in fair value is required to be recognized in current earnings if the Company intends to sell the securities or believes it likely that it will be required to sell the security before the anticipated recovery. If neither condition is met, but the Company does not expect to recover the amortized cost basis, the Company determines whether a credit loss has occurred, and the loss is then recognized in current earnings. The noncredit-related portion of the overall loss is reported in other comprehensive income (loss). Gains and losses realized upon sales of securities are calculated using the specific identification method and are included in investment securities gains (losses), net, in the consolidated statements of income. Purchase premiums and discounts are amortized to interest income using a level yield method over the estimated lives of the securities. For mortgage and asset-backed securities, prepayment experience is evaluated quarterly to determine the appropriate estimate of the future rate of prepayment. When a change in a bond's estimated remaining life is necessary, a corresponding adjustment is made in the related amortization of premium or discount accretion. Equity securities include common and preferred stock with readily determinable fair values. These are also carried at fair value. Prior to January 1, 2018, changes in fair value were recorded in other comprehensive income. The Company's adoption of ASU 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities", effective January 1, 2018, required that all subsequent changes in fair value be recorded in current earnings. The adoption also required a reclassification of the unrealized gain in fair value on equity securities (recorded in accumulated other comprehensive income at December 31, 2017) to retained earnings. The amount of this reclassification was $33.3 million, net of tax. Certain equity securities do not have readily determinable fair values. The Company has elected under ASU 2016-01 to measure these at cost minus impairment, if any, plus or minus changes resulting from observable price changes for the identical or similar investment of the same issuer. The Company has not recorded any impairment or other adjustments to the carrying amount of these investments. Other securities include Federal Reserve Bank stock and Federal Home Loan Bank stock, which are held for debt and regulatory purposes. They are carried at cost and periodically evaluated for other-than-temporary impairment. Also included are investments in portfolio concerns held by the Company’s private equity subsidiaries, which consist of both debt and equity instruments. Private equity investments are carried at fair value in accordance with ASC 946-10-15, with changes in fair value reported in current earnings. In the absence of readily ascertainable market values, fair value is estimated using internally developed methods. Changes in fair value which are recognized in current earnings and gains and losses from sales are included in investment securities gains (losses), net in the consolidated statements of income. Trading account securities, which are debt securities bought and held principally for the purpose of resale in the near term, are carried at fair value. Gains and losses, both realized and unrealized, are recorded in non-interest income. Purchases and sales of securities are recognized on a trade date basis. A receivable or payable is recognized for pending transaction settlements. Securities Purchased under Agreements to Resell and Securities Sold under Agreements to Repurchase Securities purchased under agreements to resell and securities sold under agreements to repurchase are treated as collateralized financing transactions, not as purchases and sales of the underlying securities. The agreements are recorded at the amount of cash advanced or received. The Company periodically enters into securities purchased under agreements to resell with large financial institutions. Securities pledged by the counterparties to secure these agreements are delivered to a third party custodian. Securities sold under agreements to repurchase are a source of funding to the Company and are offered to cash management customers as an automated, collateralized investment account. From time to time, securities sold may also be used by the Bank to obtain additional borrowed funds at favorable rates. These borrowings are secured by a portion of the Company's investment security portfolio and delivered either to the dealer custody account at the FRB or to the applicable counterparty. The fair value of collateral either received from or provided to a counterparty is monitored daily, and additional collateral is obtained, returned, or provided by the Company in order to maintain full collateralization for these transactions. As permitted by current accounting guidance, the Company offsets certain securities purchased under agreements to resell against securities sold under agreements to repurchase in its balance sheet presentation. These agreements are further discussed in Note 19, Resale and Repurchase Agreements. Land, Buildings and Equipment Land is stated at cost, and buildings and equipment are stated at cost, including capitalized interest when appropriate, less accumulated depreciation. Depreciation is computed using a straight-line method, utilizing estimated useful lives; generally 30 years for buildings, 10 years for building improvements, and 3 to 10 years for equipment. Leasehold improvements are amortized over the shorter of 10 years or the remaining lease term. Maintenance and repairs are charged to non-interest expense as incurred. Foreclosed Assets Foreclosed assets consist of property that has been repossessed and is comprised of commercial and residential real estate and other non-real estate property, including auto and recreational and marine vehicles. The assets are initially recorded at fair value less estimated selling costs, establishing a new cost basis. Initial valuation adjustments are charged to the allowance for loan losses. Fair values are estimated primarily based on appraisals, third-party price opinions, or internally developed pricing models. After initial recognition, fair value estimates are updated periodically. Declines in fair value below cost are recognized through valuation allowances which may be reversed when supported by future increases in fair value. These valuation adjustments, in addition to gains and losses realized on sales and net operating expenses, are recorded in other non-interest expense. Goodwill and Intangible Assets Goodwill is not amortized but is assessed for impairment on an annual basis or more frequently in certain circumstances. When testing for goodwill impairment, the Company may initially perform a qualitative assessment. Based on the results of this qualitative assessment, if the Company concludes it is more likely than not that a reporting unit's fair value is less than its carrying amount, a quantitative analysis is performed. Quantitative valuation methodologies include a combination of formulas using current market multiples, based on recent sales of financial institutions within the Company's geographic marketplace. If the fair value of a reporting unit is less than the carrying amount, additional analysis is required to measure the amount of impairment. The Company has not recorded impairment resulting from goodwill impairment tests. However, adverse changes in the economic environment, operations of the reporting unit, or other factors could result in a decline in fair value. Intangible assets that have finite useful lives, such as core deposit intangibles and mortgage servicing rights, are amortized over their estimated useful lives. Core deposit intangibles are amortized over periods of 8 to 14 years, representing their estimated lives, using accelerated methods. Mortgage servicing rights are amortized in proportion to and over the period of estimated net servicing income, considering appropriate prepayment assumptions. Core deposit intangibles are reviewed for impairment whenever events or changes in circumstances indicate their carrying amount may not be recoverable. Impairment is indicated if the sum of the undiscounted estimated future net cash flows is less than the carrying value of the intangible asset. Mortgage servicing rights, while initially recorded at fair value, are subsequently amortized and carried at the lower of the initial capitalized amount (net of accumulated amortization), or estimated fair value. The Company evaluates its mortgage servicing rights for impairment on a quarterly basis, using estimated prepayment speeds of the underlying mortgage loans serviced and stratifications based on the risk characteristics of the underlying loans. A valuation allowance has been established, through a charge to earnings, to the extent the amortized cost exceeds the estimated fair value. However, the Company has not recorded other-than-temporary impairment losses on either of these types of intangible assets. Income Taxes Amounts provided for income tax expense are based on income reported for financial statement purposes and do not necessarily represent amounts currently payable under tax laws. Deferred income taxes are provided for temporary differences between the financial reporting bases and income tax bases of the Company’s assets and liabilities, net operating losses, and tax credit carryforwards. Deferred tax assets and liabilities are measured using the enacted tax rates that are expected to apply to taxable income when such assets and liabilities are anticipated to be settled or realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized as tax expense or benefit in the period that includes the enactment date of the change. In determining the amount of deferred tax assets to recognize in the financial statements, the Company evaluates the likelihood of realizing such benefits in future periods. A valuation allowance is established if it is more likely than not that all or some portion of the deferred tax asset will not be realized. The Company recognizes interest and penalties related to income taxes within income tax expense in the consolidated statements of income. The Company and its eligible subsidiaries file a consolidated federal income tax return. State and local income tax returns are filed on a combined, consolidated or separate return basis based upon each jurisdiction’s laws and regulations. In December 2017, tax reform legislation was enacted which changed the maximum corporate tax rate for years 2018 and beyond. As such, deferred tax assets and liabilities were revalued in 2017 to account for the change in future tax rates. Additional information about current and deferred income taxes is provided in Note 8, Income Taxes. Non-Interest Income Non-interest income is mainly comprised of revenue from contracts with customers. For that revenue (excluding certain revenue associated with financial instruments, derivative and hedging instruments, guarantees, lease contracts, transferring and servicing of financial assets, and other specific revenue transactions), the Company applies the following five-step approach when recognizing revenue: (i) identify the contract with the customer, (ii) identify the performance obligations, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations, and (v) recognize revenue when (or as) the performance obligation is satisfied. The Company’s contracts with customers are generally short term in nature, with a duration of one year or less, and most contracts are cancellable by either the Company or its customer without penalty. Performance obligations for customer contracts are generally satisfied at a single point in time, typically when the transaction is complete and the customer has received the goods or service, or over time. For performance obligations satisfied over time, the Company recognizes the value of the goods or services transferred to the customer when the performance obligations have been transferred and received by the customer. Payments for satisfied performance obligations are typically due when or as the goods or services are completed, or shortly thereafter, which usually occurs within a single financial reporting period. In situations where payment is made before the performance obligation is satisfied, the fees are deferred until the performance obligations pertaining to those goods or services are completed. In cases where payment has not been received despite satisfaction of its performance obligations, the Company accrues an estimate of the amount due in the period that the performance obligations have been satisfied. For contracts with variable components, the Company only recognizes revenue to the extent that it is probable that the cumulative amount recognized will not be subject to a significant reversal in future periods. Generally, the Company’s contracts do not include terms that require significant judgment to determine whether a variable component is included within the transaction price. The Company generally acts in a principal capacity, on its own behalf, in most of its contracts with customers. For these transactions, revenue and the related costs to provide the goods or services are presented on a gross basis in the financial statements. In some cases, the Company acts in an agent capacity, deriving revenue through assisting third parties in transactions with the Company’s customers. In such transactions, revenue and the related costs to provide services is presented on a net basis in the financial statements. These transactions primarily relate to fees earned from bank card and related network and rewards costs and the sales of annuities and certain limited insurance products. Derivatives Most of the Company's derivative contracts are accounted for as free-standing instruments. These instruments are carried at fair value, and changes in fair value are recognized in current earnings. They include interest rate swaps and caps, which are offered to customers to assist in managing their risks of adverse changes in interest rates. Each contract between the Company and a customer is offset by a contract between the Company and an institutional counterparty, thus minimizing the Company's exposure to rate changes. The Company also enters into certain contracts, known as credit risk participation agreements, to buy or sell credit protection on specific interest rate swaps. It also purchases and sells forward foreign exchange contracts, either in connection with customer transactions, or for its own trading purposes. In 2015, the Company began an origination and sales program of certain personal real estate mortgages. Derivative instruments under this program include mortgage loan commitments, forward loan sale contracts, and forward contracts to sell certain to-be-announced (TBA) securities. The Company's interest rate risk management policy permits the use of hedge accounting for derivatives, and in 2018 the Company entered into interest rate floor contracts as protection from the potential for declining interest rates in the commercial loan portfolio. These floors were designated and qualified as cash flow hedges. In a cash flow hedge, the changes in fair value are recorded in accumulated other comprehensive income and recognized in the income statement when the hedged cash flows affect earnings. Both at hedge inception and on an ongoing basis, the Company assesses whether the interest rate floors used in the hedging relationships are highly effective in offsetting changes in the cash flows of the hedged items. The Company has master netting arrangements with various counterparties but does not offset derivative assets and liabilities under these arrangements in its consolidated balance sheets. However, interest rate swaps that are executed under central clearing requirements are presented net of variation margin as mandated by the statutory terms of the Company's contract with its clearing counterparty. Additional information about derivatives held by the Company and valuation methods employed is provided in Note 16, Fair Value Measurements and Note 18, Derivative Instruments. Pension Plan The Company’s pension plan is described in Note 9, Employee Benefit Plans. Historically, the Company has reported all components of net periodic pension cost in salaries and employee benefits in its consolidated statements of income. Upon the adoption of ASU 2017-07 "Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost", in 2018, only the service cost component of net periodic pension cost is reported in salaries and employee benefits in the accompanying consolidated statements of income, while the other components are reported in other non-interest expense. The funded status of the plan is recognized as an asset or liability in the consolidated balance sheets, and changes in that funded status are recognized in the year in which the changes occur through other comprehensive income. Plan assets and benefit obligations are measured as of the fiscal year end of the plan. The measurement of the projected benefit obligation and pension expense involve actuarial valuation methods and the use of various actuarial and economic assumptions. The Company monitors the assumptions and updates them periodically. Due to the long-term nature of the pension plan obligation, actual results may differ significantly from estimations. Such differences are adjusted over time as the assumptions are replaced by facts and values are recalculated. Stock-Based Compensation The Company’s stock-based employee compensation plan is described in Note 10, Stock-Based Compensation and Directors Stock Purchase Plan. In accordance with the requirements of ASC 718-10-30-3 and 35-2, the Company measures the cost of stock-based compensation based on the grant-date fair value of the award, recognizing the cost over the requisite service period, which is generally the vesting period. The fair value of an option award is estimated using the Black-Scholes option-pricing model while the fair value of a nonvested stock award is the common stock (CBSH) market price. The expense recognized for stock-based compensation is included in salaries and benefits in the accompanying consolidated statements of income. In periods prior to 2017, expense was reduced for estimated forfeitures over the vesting period and adjusted for actual forfeitures as they occurred. Effective January 1, 2017, the Company elected to recognize forfeitures as a reduction to expense only when they have occurred, as allowed under the provisions of ASU 2016-09. The effect of this change, which was recognized as a cumulative-effect adjustment on January 1, 2017, increased equity and increased deferred tax assets by approximately $1.3 million. Treasury Stock Purchases of the Company’s common stock are recorded at cost. Upon re-issuance for acquisitions, exercises of stock-based awards or other corporate purposes, treasury stock is reduced based upon the average cost basis of shares held. Income per Share Basic income per share is computed using the weighted average number of common shares outstanding during each year. Diluted income per share includes the effect of all dilutive potential common shares (primarily stock appreciation rights) outstanding during each year. The Company applies the two-class method of computing income per share. The two-class method is an earnings allocation formula that determines income per share for common stock and for participating securities, according to dividends declared and participation rights in undistributed earnings. The Company’s nonvested stock awards are considered to be a class of participating security. All per share data has been restated to reflect the 5% stock dividend distributed in December 2018.

Summary of Significant Accounting Policies

Nature of Operations

Commerce Bancshares, Inc. and its subsidiaries (the Company) conducts its principal activities from approximately 320 branch and ATM locations throughout Missouri, Illinois, Kansas, Oklahoma and Colorado. Principal activities include retail and commercial banking, investment management, securities brokerage, mortgage banking, credit related insurance and private equity investment activities. The Company also maintains commercial banking offices in Dallas, Houston, Cincinnati, Nashville, Des Moines, Indianapolis, and Grand Rapids.

Basis of Presentation

The Company follows accounting principles generally accepted in the United States of America (GAAP) and reporting practices applicable to the banking industry. The preparation of financial statements under GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and notes. These estimates are based on information available to management at the time the estimates are made. While the consolidated financial statements reflect management’s best estimates and judgments, actual results could differ from those estimates. The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries (after elimination of all material intercompany balances and transactions). Certain prior year amounts have been reclassified to conform to the current year presentation. Such reclassifications had no effect on net income or total assets. Management has evaluated subsequent events for potential recognition or disclosure through the date these consolidated financial statements were issued.

The Company, in the normal course of business, engages in a variety of activities that involve variable interest entities (VIEs). A VIE is a legal entity that lacks equity investors or whose equity investors do not have a controlling financial interest in the entity through their equity investments. However, an enterprise is deemed to have a controlling financial interest and is the primary beneficiary of a VIE if it has both the power to direct the activities of the VIE that most significantly impact the VIE’s economic performance and an obligation to absorb losses or the right to receive benefits that could potentially be significant to the VIE. An enterprise that is the primary beneficiary must consolidate the VIE. The Company’s interests in VIEs are evaluated to determine if the Company is the primary beneficiary both at inception and when there is a change in circumstances that requires a reconsideration.

The Company is considered to be the primary beneficiary in a rabbi trust related to a deferred compensation plan offered to certain employees. The assets and liabilities of this trust, which are included in the accompanying consolidated balance sheets, are not significant. The Company also has variable interests in certain entities in which it is not the primary beneficiary. These entities are not consolidated. These interests include affordable housing limited partnership interests, holdings in its investment portfolio of various asset and mortgage-backed bonds that are issued by securitization trusts, and managed discretionary trust assets that are not included in the accompanying consolidated balance sheets.

Cash, Cash Equivalents and Restricted Cash

In the accompanying consolidated statements of cash flows, cash and cash equivalents include “Cash and due from banks”, “Federal funds sold and short-term securities purchased under agreements to resell”, and “Interest earning deposits with banks” as segregated in the accompanying consolidated balance sheets. Restricted cash is comprised of cash collateral on deposit with another financial institution to secure interest rate swap transactions. Restricted cash is included in other assets in the consolidated balance sheets and totaled $8.2 million and $12.5 million at December 31, 2018 and 2017, respectively.

Regulations of the Federal Reserve System require cash balances to be maintained at the Federal Reserve Bank, based on certain deposit levels. The minimum reserve requirement for the Bank at December 31, 2018 totaled $228.3 million. Other interest earning cash balances held at the Federal Reserve Bank totaled $689.9 million.

Loans and Related Earnings

Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at their outstanding principal balances, net of undisbursed loan proceeds, the allowance for loan losses, and any deferred fees and costs on originated loans. Origination fee income received on loans and amounts representing the estimated direct costs of origination are deferred and amortized to interest income over the life of the loan using the interest method.

Interest on loans is accrued based upon the principal amount outstanding. Interest income is recognized primarily on the level yield method. Loan and commitment fees, net of costs, are deferred and recognized in income over the term of the loan or commitment as an adjustment of yield. Annual fees charged on credit card loans are capitalized to principal and amortized over 12 months to loan fees and sales. Other credit card fees, such as cash advance fees and late payment fees, are recognized in income as an adjustment of yield when charged to the cardholder’s account.

Non-Accrual Loans

Loans are placed on non-accrual status when management does not expect to collect payments consistent with acceptable and agreed upon terms of repayment. Business, construction real estate, business real estate, and personal real estate loans that are contractually 90 days past due as to principal and/or interest payments are generally placed on non-accrual, unless they are both well-secured and in the process of collection. Consumer, revolving home equity and credit card loans are exempt under regulatory rules from being classified as non-accrual. When a loan is placed on non-accrual status, any interest previously accrued but not collected is reversed against current income, and the loan is charged off to the extent uncollectible. Principal and interest payments received on non-accrual loans are generally applied to principal. Interest is included in income only after all previous loan charge-offs have been recovered and is recorded only as received. The loan is returned to accrual status only when the borrower has brought all past due principal and interest payments current, and, in the opinion of management, the borrower has demonstrated the ability to make future payments of principal and interest as scheduled. A six month history of sustained payment performance is generally required before reinstatement of accrual status.

Troubled Debt Restructurings

A loan is accounted for as a troubled debt restructuring if the Company, for economic or legal reasons related to the borrowers’ financial difficulties, grants a concession to the borrower that it would not otherwise consider. A troubled debt restructuring typically involves (1) modification of terms such as a reduction of the stated interest rate, loan principal, or accrued interest, (2) a loan renewal at a stated interest rate lower than the current market rate for a new loan with similar risk, or (3) debt that was not reaffirmed in bankruptcy. Business, business real estate, construction real estate and personal real estate troubled debt restructurings with impairment charges are placed on non-accrual status. The Company measures the impairment loss of a troubled debt restructuring in the same manner as described below. Troubled debt restructurings which are performing under their contractual terms continue to accrue interest which is recognized in current earnings.

Impaired Loans

Loans are evaluated regularly by management for impairment. Included in impaired loans are all non-accrual loans, as well as loans that have been classified as troubled debt restructurings. Once a loan has been identified as impaired, impairment is measured based on either the present value of the expected future cash flows at the loan’s initial effective interest rate or the fair value of the collateral if collateral dependent. Factors considered in determining impairment include delinquency status, cash flow analysis, credit analysis, and collateral value and availability.

Loans Held For Sale

Loans held for sale include student loans and certain fixed rate residential mortgage loans. These loans are typically classified as held for sale upon origination based upon management's intent to sell the production of these loans. The student loans are carried at the lower of aggregate cost or fair value, and their fair value is determined based on sale contract prices. The mortgage loans are carried at fair value under the elected fair value option. Their fair value is based on secondary market prices for loans with similar characteristics, including an adjustment for embedded servicing value. Changes in fair value and gains and losses on sales are included in loan fees and sales. Deferred fees and costs related to these loans are not amortized but are recognized as part of the cost basis of the loan at the time it is sold. Interest income related to loans held for sale is accrued based on the principal amount outstanding and the loan's contractual interest rate.

Occasionally, other types of loans may be classified as held for sale in order to manage credit concentration. These loans are carried at the lower of cost or fair value with gains and losses on sales recognized in loan fees and sales.

Allowance/Provision for Loan Losses

The allowance for loan losses is maintained at a level believed to be appropriate by management to provide for probable loan losses inherent in the portfolio as of the balance sheet date, including losses on known or anticipated problem loans as well as for loans which are not currently known to require specific allowances. Management has established a process to determine the amount of the allowance for loan losses which assesses the risks and losses inherent in its portfolio. Business, construction real estate and business real estate loans are normally larger and more complex, and their collection rates are harder to predict. These loans are more likely to be collateral dependent and are allocated a larger reserve, due to their potential volatility. Personal real estate, credit card, consumer and revolving home equity loans are individually smaller and perform in a more homogenous manner, making loss estimates more predictable. Management’s process provides an allowance consisting of a specific allowance component based on certain individually evaluated loans and a general component based on estimates of reserves needed for pools of loans.

Loans subject to individual evaluation generally consist of business, construction real estate, business real estate and personal real estate loans on non-accrual status. These impaired loans are evaluated individually for the impairment of repayment potential and collateral adequacy. Other impaired loans identified as performing troubled debt restructurings are collectively evaluated because they have similar risk characteristics. Loans which have not been identified as impaired are segregated by loan type and sub-type and are collectively evaluated. Reserves calculated for these loan pools are estimated using a consistent methodology that considers historical loan loss experience by loan type, loss emergence periods, delinquencies, current economic factors, loan risk ratings and industry concentrations.

The Company’s estimate of the allowance for loan losses and the corresponding provision for loan losses is based on various judgments and assumptions made by management. The amount of the allowance for loan losses is influenced by several qualitative factors which include collateral valuation, evaluation of performance and status, current loan portfolio composition and characteristics, trends in delinquencies, portfolio risk ratings, levels of non-performing assets, and prevailing regional and national economic and business conditions.

The estimates, appraisals, evaluations, and cash flows utilized by management may be subject to frequent adjustments due to changing economic prospects of borrowers or properties. These estimates are reviewed periodically and adjustments, if necessary, are recorded in the provision for loan losses in the periods in which they become known.

Loans, or portions of loans, are charged off to the extent deemed uncollectible. Loan charge-offs reduce the allowance for loan losses, and recoveries of loans previously charged off are added back to the allowance. Business, business real estate, construction real estate and personal real estate loans are generally charged down to estimated collectible balances when they are placed on non-accrual status. Consumer loans and related accrued interest are normally charged down to the fair value of related collateral (or are charged off in full if no collateral) once the loans are more than 120 days delinquent. Credit card loans are charged off against the allowance for loan losses when the receivable is more than 180 days past due. The interest and fee income previously capitalized but not collected on credit card charge-offs is reversed against interest income.

Operating, Direct Financing and Sales Type Leases

The net investment in direct financing and sales type leases is included in loans on the Company’s consolidated balance sheets and consists of the present values of the sum of the future minimum lease payments and estimated residual value of the leased asset. Revenue consists of interest earned on the net investment and is recognized over the lease term as a constant percentage return thereon. The net investment in operating leases is included in other assets on the Company’s consolidated balance sheets. It is carried at cost, less the amount depreciated to date. Depreciation is recognized on a straight-line basis over the lease term to the estimated residual value. Operating lease revenue consists of the contractual lease payments and is recognized over the lease term in other non-interest income. Estimated residual values are established at lease inception utilizing contract terms, past customer experience, and general market data and are reviewed and adjusted, if necessary, on an annual basis.

Investments in Debt and Equity Securities

The majority of the Company's investment portfolio is comprised of debt securities which are classified as available for sale. From time to time, the Company sells securities and utilizes the proceeds to reduce borrowings, fund loan growth, or modify its interest rate profile. Securities classified as available for sale are carried at fair value. Changes in fair value, excluding certain losses associated with other-than-temporary impairment (OTTI), are reported in other comprehensive income (loss), a component of stockholders’ equity. Securities are periodically evaluated for OTTI in accordance with guidance provided in ASC 320-10-35. For securities with OTTI, the entire loss in fair value is required to be recognized in current earnings if the Company intends to sell the securities or believes it likely that it will be required to sell the security before the anticipated recovery. If neither condition is met, but the Company does not expect to recover the amortized cost basis, the Company determines whether a credit loss has occurred, and the loss is then recognized in current earnings. The noncredit-related portion of the overall loss is reported in other comprehensive income (loss). Gains and losses realized upon sales of securities are calculated using the specific identification method and are included in investment securities gains (losses), net, in the consolidated statements of income. Purchase premiums and discounts are amortized to interest income using a level yield method over the estimated lives of the securities. For mortgage and asset-backed securities, prepayment experience is evaluated quarterly to determine the appropriate estimate of the future rate of prepayment. When a change in a bond's estimated remaining life is necessary, a corresponding adjustment is made in the related amortization of premium or discount accretion.

Equity securities include common and preferred stock with readily determinable fair values. These are also carried at fair value. Prior to January 1, 2018, changes in fair value were recorded in other comprehensive income. The Company's adoption of ASU 2016-01, "Recognition and Measurement of Financial Assets and Financial Liabilities", effective January 1, 2018, required that all subsequent changes in fair value be recorded in current earnings. The adoption also required a reclassification of the unrealized gain in fair value on equity securities (recorded in accumulated other comprehensive income at December 31, 2017) to retained earnings. The amount of this reclassification was $33.3 million, net of tax.

Certain equity securities do not have readily determinable fair values. The Company has elected under ASU 2016-01 to measure these at cost minus impairment, if any, plus or minus changes resulting from observable price changes for the identical or similar investment of the same issuer. The Company has not recorded any impairment or other adjustments to the carrying amount of these investments.

Other securities include Federal Reserve Bank stock and Federal Home Loan Bank stock, which are held for debt and regulatory purposes. They are carried at cost and periodically evaluated for other-than-temporary impairment. Also included are investments in portfolio concerns held by the Company’s private equity subsidiaries, which consist of both debt and equity instruments. Private equity investments are carried at fair value in accordance with ASC 946-10-15, with changes in fair value reported in current earnings. In the absence of readily ascertainable market values, fair value is estimated using internally developed methods. Changes in fair value which are recognized in current earnings and gains and losses from sales are included in investment securities gains (losses), net in the consolidated statements of income.

Trading account securities, which are debt securities bought and held principally for the purpose of resale in the near term, are carried at fair value. Gains and losses, both realized and unrealized, are recorded in non-interest income.

Purchases and sales of securities are recognized on a trade date basis. A receivable or payable is recognized for pending transaction settlements.

Securities Purchased under Agreements to Resell and Securities Sold under Agreements to Repurchase

Securities purchased under agreements to resell and securities sold under agreements to repurchase are treated as collateralized financing transactions, not as purchases and sales of the underlying securities. The agreements are recorded at the amount of cash advanced or received.

The Company periodically enters into securities purchased under agreements to resell with large financial institutions. Securities pledged by the counterparties to secure these agreements are delivered to a third party custodian.

Securities sold under agreements to repurchase are a source of funding to the Company and are offered to cash management customers as an automated, collateralized investment account. From time to time, securities sold may also be used by the Bank to obtain additional borrowed funds at favorable rates. These borrowings are secured by a portion of the Company's investment security portfolio and delivered either to the dealer custody account at the FRB or to the applicable counterparty.

The fair value of collateral either received from or provided to a counterparty is monitored daily, and additional collateral is obtained, returned, or provided by the Company in order to maintain full collateralization for these transactions.

As permitted by current accounting guidance, the Company offsets certain securities purchased under agreements to resell against securities sold under agreements to repurchase in its balance sheet presentation. These agreements are further discussed in Note 19, Resale and Repurchase Agreements.

Land, Buildings and Equipment

Land is stated at cost, and buildings and equipment are stated at cost, including capitalized interest when appropriate, less accumulated depreciation. Depreciation is computed using a straight-line method, utilizing estimated useful lives; generally 30 years for buildings, 10 years for building improvements, and 3 to 10 years for equipment. Leasehold improvements are amortized over the shorter of 10 years or the remaining lease term. Maintenance and repairs are charged to non-interest expense as incurred.

Foreclosed Assets

Foreclosed assets consist of property that has been repossessed and is comprised of commercial and residential real estate and other non-real estate property, including auto and recreational and marine vehicles. The assets are initially recorded at fair value less estimated selling costs, establishing a new cost basis. Initial valuation adjustments are charged to the allowance for loan losses. Fair values are estimated primarily based on appraisals, third-party price opinions, or internally developed pricing models. After initial recognition, fair value estimates are updated periodically. Declines in fair value below cost are recognized through valuation allowances which may be reversed when supported by future increases in fair value. These valuation adjustments, in addition to gains and losses realized on sales and net operating expenses, are recorded in other non-interest expense.

Goodwill and Intangible Assets

Goodwill is not amortized but is assessed for impairment on an annual basis or more frequently in certain circumstances. When testing for goodwill impairment, the Company may initially perform a qualitative assessment. Based on the results of this qualitative assessment, if the Company concludes it is more likely than not that a reporting unit's fair value is less than its carrying amount, a quantitative analysis is performed. Quantitative valuation methodologies include a combination of formulas using current market multiples, based on recent sales of financial institutions within the Company's geographic marketplace. If the fair value of a reporting unit is less than the carrying amount, additional analysis is required to measure the amount of impairment. The Company has not recorded impairment resulting from goodwill impairment tests. However, adverse changes in the economic environment, operations of the reporting unit, or other factors could result in a decline in fair value.

Intangible assets that have finite useful lives, such as core deposit intangibles and mortgage servicing rights, are amortized over their estimated useful lives. Core deposit intangibles are amortized over periods of 8 to 14 years, representing their estimated lives, using accelerated methods. Mortgage servicing rights are amortized in proportion to and over the period of estimated net servicing income, considering appropriate prepayment assumptions. Core deposit intangibles are reviewed for impairment whenever events or changes in circumstances indicate their carrying amount may not be recoverable. Impairment is indicated if the sum of the undiscounted estimated future net cash flows is less than the carrying value of the intangible asset. Mortgage servicing rights, while initially recorded at fair value, are subsequently amortized and carried at the lower of the initial capitalized amount (net of accumulated amortization), or estimated fair value. The Company evaluates its mortgage servicing rights for impairment on a quarterly basis, using estimated prepayment speeds of the underlying mortgage loans serviced and stratifications based on the risk characteristics of the underlying loans. A valuation allowance has been established, through a charge to earnings, to the extent the amortized cost exceeds the estimated fair value. However, the Company has not recorded other-than-temporary impairment losses on either of these types of intangible assets.

Income Taxes

Amounts provided for income tax expense are based on income reported for financial statement purposes and do not necessarily represent amounts currently payable under tax laws. Deferred income taxes are provided for temporary differences between the financial reporting bases and income tax bases of the Company’s assets and liabilities, net operating losses, and tax credit carryforwards. Deferred tax assets and liabilities are measured using the enacted tax rates that are expected to apply to taxable income when such assets and liabilities are anticipated to be settled or realized. The effect on deferred tax assets and liabilities of a change in tax rates is recognized as tax expense or benefit in the period that includes the enactment date of the change. In determining the amount of deferred tax assets to recognize in the financial statements, the Company evaluates the likelihood of realizing such benefits in future periods. A valuation allowance is established if it is more likely than not that all or some portion of the deferred tax asset will not be realized. The Company recognizes interest and penalties related to income taxes within income tax expense in the consolidated statements of income.

The Company and its eligible subsidiaries file a consolidated federal income tax return. State and local income tax returns are filed on a combined, consolidated or separate return basis based upon each jurisdiction’s laws and regulations.

In December 2017, tax reform legislation was enacted which changed the maximum corporate tax rate for years 2018 and beyond. As such, deferred tax assets and liabilities were revalued in 2017 to account for the change in future tax rates. Additional information about current and deferred income taxes is provided in Note 8, Income Taxes.

Non-Interest Income

Non-interest income is mainly comprised of revenue from contracts with customers. For that revenue (excluding certain revenue associated with financial instruments, derivative and hedging instruments, guarantees, lease contracts, transferring and servicing of financial assets, and other specific revenue transactions), the Company applies the following five-step approach when recognizing revenue: (i) identify the contract with the customer, (ii) identify the performance obligations, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations, and (v) recognize revenue when (or as) the performance obligation is satisfied. The Company’s contracts with customers are generally short term in nature, with a duration of one year or less, and most contracts are cancellable by either the Company or its customer without penalty. Performance obligations for customer contracts are generally satisfied at a single point in time, typically when the transaction is complete and the customer has received the goods or service, or over time. For performance obligations satisfied over time, the Company recognizes the value of the goods or services transferred to the customer when the performance obligations have been transferred and received by the customer. Payments for satisfied performance obligations are typically due when or as the goods or services are completed, or shortly thereafter, which usually occurs within a single financial reporting period.

In situations where payment is made before the performance obligation is satisfied, the fees are deferred until the performance obligations pertaining to those goods or services are completed. In cases where payment has not been received despite satisfaction of its performance obligations, the Company accrues an estimate of the amount due in the period that the performance obligations have been satisfied. For contracts with variable components, the Company only recognizes revenue to the extent that it is probable that the cumulative amount recognized will not be subject to a significant reversal in future periods. Generally, the Company’s contracts do not include terms that require significant judgment to determine whether a variable component is included within the transaction price. The Company generally acts in a principal capacity, on its own behalf, in most of its contracts with customers. For these transactions, revenue and the related costs to provide the goods or services are presented on a gross basis in the financial statements. In some cases, the Company acts in an agent capacity, deriving revenue through assisting third parties in transactions with the Company’s customers. In such transactions, revenue and the related costs to provide services is presented on a net basis in the financial statements. These transactions primarily relate to fees earned from bank card and related network and rewards costs and the sales of annuities and certain limited insurance products.

Derivatives

Most of the Company's derivative contracts are accounted for as free-standing instruments. These instruments are carried at fair value, and changes in fair value are recognized in current earnings. They include interest rate swaps and caps, which are offered to customers to assist in managing their risks of adverse changes in interest rates. Each contract between the Company and a customer is offset by a contract between the Company and an institutional counterparty, thus minimizing the Company's exposure to rate changes. The Company also enters into certain contracts, known as credit risk participation agreements, to buy or sell credit protection on specific interest rate swaps. It also purchases and sells forward foreign exchange contracts, either in connection with customer transactions, or for its own trading purposes. In 2015, the Company began an origination and sales program of certain personal real estate mortgages. Derivative instruments under this program include mortgage loan commitments, forward loan sale contracts, and forward contracts to sell certain to-be-announced (TBA) securities.

The Company's interest rate risk management policy permits the use of hedge accounting for derivatives, and in 2018 the Company entered into interest rate floor contracts as protection from the potential for declining interest rates in the commercial loan portfolio. These floors were designated and qualified as cash flow hedges. In a cash flow hedge, the changes in fair value are recorded in accumulated other comprehensive income and recognized in the income statement when the hedged cash flows affect earnings. Both at hedge inception and on an ongoing basis, the Company assesses whether the interest rate floors used in the hedging relationships are highly effective in offsetting changes in the cash flows of the hedged items.

The Company has master netting arrangements with various counterparties but does not offset derivative assets and liabilities under these arrangements in its consolidated balance sheets. However, interest rate swaps that are executed under central clearing requirements are presented net of variation margin as mandated by the statutory terms of the Company's contract with its clearing counterparty.

Additional information about derivatives held by the Company and valuation methods employed is provided in Note 16, Fair Value Measurements and Note 18, Derivative Instruments.

Pension Plan

The Company’s pension plan is described in Note 9, Employee Benefit Plans. Historically, the Company has reported all components of net periodic pension cost in salaries and employee benefits in its consolidated statements of income. Upon the adoption of ASU 2017-07 "Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost", in 2018, only the service cost component of net periodic pension cost is reported in salaries and employee benefits in the accompanying consolidated statements of income, while the other components are reported in other non-interest expense. The funded status of the plan is recognized as an asset or liability in the consolidated balance sheets, and changes in that funded status are recognized in the year in which the changes occur through other comprehensive income. Plan assets and benefit obligations are measured as of the fiscal year end of the plan. The measurement of the projected benefit obligation and pension expense involve actuarial valuation methods and the use of various actuarial and economic assumptions. The Company monitors the assumptions and updates them periodically. Due to the long-term nature of the pension plan obligation, actual results may differ significantly from estimations. Such differences are adjusted over time as the assumptions are replaced by facts and values are recalculated.

Stock-Based Compensation

The Company’s stock-based employee compensation plan is described in Note 10, Stock-Based Compensation and Directors Stock Purchase Plan. In accordance with the requirements of ASC 718-10-30-3 and 35-2, the Company measures the cost of stock-based compensation based on the grant-date fair value of the award, recognizing the cost over the requisite service period, which is generally the vesting period. The fair value of an option award is estimated using the Black-Scholes option-pricing model while the fair value of a nonvested stock award is the common stock (CBSH) market price. The expense recognized for stock-based compensation is included in salaries and benefits in the accompanying consolidated statements of income. In periods prior to 2017, expense was reduced for estimated forfeitures over the vesting period and adjusted for actual forfeitures as they occurred. Effective January 1, 2017, the Company elected to recognize forfeitures as a reduction to expense only when they have occurred, as allowed under the provisions of ASU 2016-09. The effect of this change, which was recognized as a cumulative-effect adjustment on January 1, 2017, increased equity and increased deferred tax assets by approximately $1.3 million.

Treasury Stock

Purchases of the Company’s common stock are recorded at cost. Upon re-issuance for acquisitions, exercises of stock-based awards or other corporate purposes, treasury stock is reduced based upon the average cost basis of shares held.

Income per Share

Basic income per share is computed using the weighted average number of common shares outstanding during each year. Diluted income per share includes the effect of all dilutive potential common shares (primarily stock appreciation rights) outstanding during each year. The Company applies the two-class method of computing income per share. The two-class method is an earnings allocation formula that determines income per share for common stock and for participating securities, according to dividends declared and participation rights in undistributed earnings. The Company’s nonvested stock awards are considered to be a class of participating security. All per share data has been restated to reflect the 5% stock dividend distributed in December 2018.