Summary of Significant Accounting Policies (Policy)	12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]
Nature Of Operations	Nature of Operations Commerce Bancshares, Inc. and its subsidiaries (the Company) conducts its principal activities from approximately 257 branch and ATM locations throughout Missouri, Kansas, Illinois, Oklahoma and Colorado. Principal activities include retail and commercial banking, investment management, securities brokerage, mortgage banking, trust, and private banking services. The Company also maintains offices in Dallas, Houston, Cincinnati, Nashville, Des Moines, Indianapolis, and Grand Rapids that support customers in its commercial and/or wealth segments and operates a commercial payments business with sales representatives covering the continental U.S.
Basis Of Presentation	Basis of Presentation, Use of Estimates, and Subsequent Events The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. All material inter-company transactions have been eliminated through consolidation. 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. 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 consolidated 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. 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 certain investments in entities accounted for using the equity method of accounting, as well as 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.
New Accounting Pronouncements, Policy	Adoption of ASU 2022-02 The Company adopted ASU 2022-02 Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures on January 1, 2023, using the prospective transition method. This ASU eliminates the troubled debt restructuring recognition and measurement guidance and requires an entity to present gross write-offs by year of origination. The amendments also enhance disclosure requirements related to certain modifications of receivables made to borrowers experiencing financial difficulty. With the exception of enhanced disclosures, there was no material impact to the Company's consolidated financial statements from adoption of this ASU. Since the Company's adoption date, all restructurings are evaluated to determine whether they are modifications to a borrower experiencing financial difficulty. Loans that were accounted for under the troubled debt restructuring method as of December 31, 2022 will continue to be accounted for under that method until they are paid off or modified.
Cash, Cash Equivalents and Restricted Cash	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", "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 $101 thousand and $6.7 million at December 31, 2023 and 2022, respectively. During 2020, the Federal Reserve System, which historically required the Bank to maintain cash balances at the Federal Reserve Bank, reduced the reserve requirement ratios to zero percent effective March 26, 2020. Other interest earning cash balances held at the Federal Reserve Bank totaled $2.2 billion at December 31, 2023.
Loans And Related Earnings	Loans and Related Earnings The Company's portfolio of held-for-investment loans includes a net investment in direct financing and sales type leases to commercial and industrial and tax-exempt entities, and collectively, the Company's portfolio of loans and leases is referred to as its "loan portfolio" or "loans". Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at amortized cost, excluding accrued interest receivable. Amortized cost is the outstanding principal balance, net of 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. The Company has elected the practical expedient to exclude all accrued interest receivable from all required disclosures of amortized cost. Additionally, an election was made not to measure an allowance for credit losses for accrued interest receivables. The Company has also made the election that all interest accrued but ultimately not received is reversed against interest income. Loan and commitment fees, net of costs, are deferred and recognized in interest 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.
Loans and Leases Receivable, Past Due Status, Policy	Past Due Loans Management reports loans as past due on the day following the contractual repayment date if payment was not received by end of the business day. Loans, or portions of loans, are charged off to the extent deemed uncollectible. Loan charge-offs reduce the allowance for credit losses on loans, and recoveries of loans previously charged off are added back to the allowance. Business, business real estate, construction and land 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 not collateralized) once the loans are more than 120 to 180 days delinquent, depending on the type of loan. Revolving home equity loans are charged down to the fair value of the related collateral once the loans are more than 180 days past due. Credit card loans are charged off against the allowance for credit losses when the receivable is more than 180 days past due.
Non-Accrual Loans	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 status, 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 interest 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.
Restructured Loans	Modifications for Borrowers Experiencing Financial Difficulty The Company may renegotiate the terms of existing loans for a variety of reasons. When refinancing or restructuring a loan, the Company evaluates whether the borrower is experiencing financial difficulty. In making this determination, the Company considers whether the borrower is currently in default on any of its debt. In addition, the Company evaluates whether it is probable that the borrower would be in payment default on any of its debt in the foreseeable future without the modification and if the borrower (without the current modification) could obtain equivalent financing from another creditor at a market rate for similar debt. Modifications of loans to borrowers in these situations may indicate that the borrower is facing financial difficulty. Troubled Debt Restructurings Prior to the Company's adoption of ASU 2022-02, a loan was accounted for as a troubled debt restructuring if the Company, for economic or legal reasons related to the borrower's financial difficulties, granted 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 and land real estate and personal real estate troubled debt restructurings with impairment charges were placed on non-accrual status. The Company measured the impairment loss of a troubled debt restructuring at the time of modification based on the present value of expected future cash flows. Subsequent to modification, troubled debt restructurings were subject to the Company’s allowance for credit loss model, which is discussed below and in Note 2, Loans and Allowance for Credit Losses. Troubled debt restructurings that are performing under their contractual terms continue to accrue interest, which is recognized in current earnings. Loans that were accounted as troubled debt restructurings at of December 31, 2022 will continue to be accounted for under that method until they are either paid off or modified.
Loans Held For Sale	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.
Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts	Allowance for Credit Losses on Loans The allowance for credit losses on loans is a valuation amount that is deducted from the amortized cost basis of loans not held at fair value to present the net amount expected to be collected over the contractual term of the loans. The allowance for credit losses on loans is measured using relevant information about past events, including historical credit loss experience on loans with similar risk characteristics, current conditions, and reasonable and supportable forecasts that affect the collectability of the remaining cash flows over the contractual term of the loans. An allowance will be created upon origination or acquisition of a loan and is updated at subsequent reporting dates. The methodology is applied consistently for each reporting period and reflects management’s current expectations of credit losses. Changes to the allowance for credit losses on loans resulting from periodic evaluations are recorded through increases or decreases to the credit loss expense for loans, which is recorded in provision for credit losses on the consolidated statements of income. Loans that are deemed to be uncollectible are charged off against the related allowance for credit losses on loans. The allowance for credit losses on loans is measured on a collective (pool) basis. Loans are aggregated into pools based on similar risk characteristics including borrower type, collateral type and expected credit loss patterns. Loans that do not share similar risk characteristics, primarily large loans on non-accrual status, are evaluated on an individual basis. The allowance related to these large non-accrual loans is generally measured using the fair value of the collateral (less selling cost, if applicable) as most of these loans are collateral dependent and the borrower is facing financial difficulty. As noted above, the allowance for credit losses on loans does not include an allowance for accrued interest.
Off-Balance-Sheet Credit Exposure, Policy	Liability for Unfunded Lending Commitments The Company’s unfunded lending commitments are primarily unfunded loan commitments and letters of credit. Expected credit losses for these unfunded lending commitments are calculated over the contractual period during which the Company is exposed to the credit risk. The methodology used to measure credit losses for unfunded lending commitments is the same as the methodology used for loans, however, the estimate of credit risk for unfunded lending commitments takes into consideration the likelihood that funding will occur. The liability for unfunded lending commitments excludes any exposures that are unconditionally cancellable by the Company. The loss estimate is recorded within other liabilities on the consolidated balance sheet. Changes to the liability for unfunded lending commitments are recorded through increases or decreases to the provision for credit losses on the consolidated statements of income.
Direct Financing And Sales Type Leases	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.
Investments In Debt And Equity Securities	Investments in Debt and Equity Securities The majority of the Company's investment portfolio is comprised of debt securities that 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 are reported in other comprehensive income (loss), a component of stockholders’ equity. Securities are periodically evaluated for credit losses in accordance with the guidance provided in Accounting Standards Codification (ASC) 326. Further discussion of this evaluation is provided in "Allowance for Credit Losses on Available for Sale Debt Securities" below. 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 certain callable debt securities purchased at a premium, the amortization is recorded to the earliest call date. For mortgage and asset-backed securities, prepayment experience is evaluated quarterly to determine if a change in a bond's estimated remaining life is necessary. A corresponding adjustment is then made in the related amortization of premium or discount accretion. Accrued interest receivable on available for sale debt securities is reported in other assets on the consolidated balance sheet. The Company has elected the practical expedient to exclude the accrued interest from all required disclosures of amortized cost of debt securities. Additionally, an election was made not to measure an allowance for credit losses for accrued interest receivables. Interest accrued but not received is reversed against interest income. Equity securities include common and preferred stock and are carried at fair value. Certain equity securities do not have readily determinable fair values. The Company has elected to measure these equity securities without a readily determinable fair value 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 equity securities without readily determinable fair values. Other securities include the Company's investments in Federal Reserve Bank stock and Federal Home Loan Bank stock, equity method investments, and private equity investments. Federal Reserve Bank stock and Federal Home Loan Bank stock are held for debt and regulatory purposes, are carried at cost and are periodically evaluated for impairment. The Company's equity method investments are carried at cost, adjusted to reflect the Company's portion of income, loss, or dividends of the investee. The Company's private equity investments in portfolio concerns, consisting of both debt and equity instruments, are held by the Company’s private equity subsidiary, which is a small business investment company licensed by the Small Business Administration. The Company's private equity investments are carried at fair value in accordance with investment company accounting guidance (ASC 946-10-15), with changes in fair value reported in current income. 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 income 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 transaction pending settlements.
Credit Loss, Financial Instrument	Allowance for Credit Losses on Available for Sale Debt Securities For available for sale debt securities in an unrealized loss position, 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 more likely than not that it will be required to sell the security before the anticipated recovery. If neither condition is met, and the Company does not expect to recover the amortized cost basis, the Company determines whether the decline in fair value resulted from credit losses or other factors. If the assessment indicates that a credit loss exists, the present value of cash flows expected to be collected is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss has occurred, and an allowance for credit losses is recorded. The allowance for credit losses is limited by the amount that the fair value is less than the amortized cost basis. Any impairment not recorded through the provision for credit losses is recognized in other comprehensive income. Changes in the allowance for credit losses are recorded as a provision for (or reversal of) credit losses on the consolidated statements of income. Losses are charged against the allowance for credit losses on securities when management believes the uncollectibility of an available for sale security is confirmed or when either of the conditions regarding intent or requirement to sell is met. Accrued interest receivable on available for sale debt securities is excluded from the estimate of credit losses.
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 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 Federal Reserve Bank 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 20, Resale and Repurchase Agreements.
Premises and Equipment	Premises 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 to 40 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. Also included in premises and equipment is construction in process, which represents facilities construction projects underway that have not yet been placed into service, as well as the Company's right-of-use leased assets, which are mainly comprised of operating leases for branches, office space, ATM locations, and certain equipment.
Foreclosed Assets	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 credit 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. Foreclosed assets are included in other assets on the consolidated balance sheets.
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill and intangible assets that have indefinite useful lives, such as property easement intangible assets, are not amortized but are 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, an impairment has occurred and is measured as the amount by which the carrying amount exceeds the reporting unit's fair value. 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 generally 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 its intangible assets.
Income Taxes	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. Additional information about current and deferred income taxes is provided in Note 9, Income Taxes.
Non-Interest Income	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, the sales of annuities and certain limited insurance products, and beginning in August 2023, commissions on sales of consumer brokerage transactions and products.
Derivatives	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. Additionally, the Company originates and sells 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 the Company has 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. From time to time, the Company has monetized its interest rate floors that had previously been designated and qualified as cash flow hedges. In such case, the monetized cash flow hedge is derecognized and the amounts recorded in accumulated other comprehensive income (AOCI) remain in AOCI until the underlying forecasted transaction impacts earnings, unless the forecasted transaction becomes probable of not occurring. 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 17, Fair Value Measurements and Note 19, Derivative Instruments. Cash flows associated with derivative instruments and their related gains and losses are presented in the consolidated statement of cash flows as operating activities.
Pension Plan	Pension Plan The Company’s pension plan is described in Note 10, Employee Benefit Plans. In accordance with ASU 2017-07, the Company has reported the service cost component of net periodic pension cost 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 other asset or other 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	Stock-Based Compensation The Company’s stock-based compensation plan is described in Note 11, 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 stock appreciation rights 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. The Company recognizes forfeitures as a reduction to expense only when they have occurred.
Treasury Stock	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	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 2023.

Summary of Significant Accounting Policies (Policy)

12 Months Ended

Dec. 31, 2023

Nature of Operations

Commerce Bancshares, Inc. and its subsidiaries (the Company) conducts its principal activities from approximately 257 branch and ATM locations throughout Missouri, Kansas, Illinois, Oklahoma and Colorado. Principal activities include retail and commercial banking, investment management, securities brokerage, mortgage banking, trust, and private banking services. The Company also maintains offices in Dallas, Houston, Cincinnati, Nashville, Des Moines, Indianapolis, and Grand Rapids that support customers in its commercial and/or wealth segments and operates a commercial payments business with sales representatives covering the continental U.S.

Basis Of Presentation

Basis of Presentation, Use of Estimates, and Subsequent Events

The consolidated financial statements include the accounts of the Company and its majority-owned subsidiaries. All material inter-company transactions have been eliminated through consolidation. 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.

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 consolidated 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.

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 certain investments in entities accounted for using the equity method of accounting, as well as 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.

New Accounting Pronouncements, Policy

Adoption of ASU 2022-02

The Company adopted ASU 2022-02 Financial Instruments—Credit Losses (Topic 326): Troubled Debt Restructurings and Vintage Disclosures on January 1, 2023, using the prospective transition method. This ASU eliminates the troubled debt restructuring recognition and measurement guidance and requires an entity to present gross write-offs by year of origination. The amendments also enhance disclosure requirements related to certain modifications of receivables made to borrowers experiencing financial difficulty. With the exception of enhanced disclosures, there was no material impact to the Company's consolidated financial statements from adoption of this ASU. Since the Company's adoption date, all restructurings are evaluated to determine whether they are modifications to a borrower experiencing financial difficulty. Loans that were accounted for under the troubled debt restructuring method as of December 31, 2022 will continue to be accounted for under that method until they are paid off or modified.

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", "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 $101 thousand and $6.7 million at December 31, 2023 and 2022, respectively.

During 2020, the Federal Reserve System, which historically required the Bank to maintain cash balances at the Federal Reserve Bank, reduced the reserve requirement ratios to zero percent effective March 26, 2020. Other interest earning cash balances held at the Federal Reserve Bank totaled $2.2 billion at December 31, 2023.

Loans And Related Earnings

Loans and Related Earnings

The Company's portfolio of held-for-investment loans includes a net investment in direct financing and sales type leases to commercial and industrial and tax-exempt entities, and collectively, the Company's portfolio of loans and leases is referred to as its "loan portfolio" or "loans". Loans that management has the intent and ability to hold for the foreseeable future or until maturity or pay-off are reported at amortized cost, excluding accrued interest receivable. Amortized cost is the outstanding principal balance, net of 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. The Company has elected the practical expedient to exclude all accrued interest receivable from all required disclosures of amortized cost. Additionally, an election was made not to measure an allowance for credit losses for accrued interest receivables. The Company has also made the election that all interest accrued but ultimately not received is reversed against interest income.

Loan and commitment fees, net of costs, are deferred and recognized in interest 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.

Loans and Leases Receivable, Past Due Status, Policy

Past Due Loans

Management reports loans as past due on the day following the contractual repayment date if payment was not received by end of the business day. Loans, or portions of loans, are charged off to the extent deemed uncollectible. Loan charge-offs reduce the allowance for credit losses on loans, and recoveries of loans previously charged off are added back to the allowance. Business, business real estate, construction and land 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 not collateralized) once the loans are more than 120 to 180 days delinquent, depending on the type of loan. Revolving home equity loans are charged down to the fair value of the related collateral once the loans are more than 180 days past due. Credit card loans are charged off against the allowance for credit losses when the receivable is more than 180 days past due.

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 status, 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 interest 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.

Restructured Loans

Modifications for Borrowers Experiencing Financial Difficulty

The Company may renegotiate the terms of existing loans for a variety of reasons. When refinancing or restructuring a loan, the Company evaluates whether the borrower is experiencing financial difficulty. In making this determination, the Company considers whether the borrower is currently in default on any of its debt. In addition, the Company evaluates whether it is probable that the borrower would be in payment default on any of its debt in the foreseeable future without the modification and if the borrower (without the current modification) could obtain equivalent financing from another creditor at a market rate for similar debt. Modifications of loans to borrowers in these situations may indicate that the borrower is facing financial difficulty.

Troubled Debt Restructurings

Prior to the Company's adoption of ASU 2022-02, a loan was accounted for as a troubled debt restructuring if the Company, for economic or legal reasons related to the borrower's financial difficulties, granted 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 and land real estate and personal real estate troubled debt restructurings with impairment charges were placed on non-accrual status. The Company measured the impairment loss of a troubled debt restructuring at the time of modification based on the present value of expected future cash flows. Subsequent to modification, troubled debt restructurings were subject to the Company’s allowance for credit loss model, which is discussed below and in Note 2, Loans and Allowance for Credit Losses. Troubled debt restructurings that are performing under their contractual terms continue to accrue interest, which is recognized in current earnings. Loans that were accounted as troubled debt restructurings at of December 31, 2022 will continue to be accounted for under that method until they are either paid off or modified.

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.

Financing Receivable, Allowance for Credit Losses, Policy for Uncollectible Amounts

Allowance for Credit Losses on Loans

The allowance for credit losses on loans is a valuation amount that is deducted from the amortized cost basis of loans not held at fair value to present the net amount expected to be collected over the contractual term of the loans. The allowance for credit losses on loans is measured using relevant information about past events, including historical credit loss experience on loans with similar risk characteristics, current conditions, and reasonable and supportable forecasts that affect the collectability of the remaining cash flows over the contractual term of the loans. An allowance will be created upon origination or acquisition of a loan and is updated at subsequent reporting dates. The methodology is applied consistently for each reporting period and reflects management’s current expectations of credit losses. Changes to the allowance for credit losses on loans resulting from periodic evaluations are recorded through increases or decreases to the credit loss expense for loans, which is recorded in provision for credit losses on the consolidated statements of income. Loans that are deemed to be uncollectible are charged off against the related allowance for credit losses on loans.

The allowance for credit losses on loans is measured on a collective (pool) basis. Loans are aggregated into pools based on similar risk characteristics including borrower type, collateral type and expected credit loss patterns. Loans that do not share similar risk characteristics, primarily large loans on non-accrual status, are evaluated on an individual basis. The allowance related to these large non-accrual loans is generally measured using the fair value of the collateral (less selling cost, if applicable) as most of these loans are collateral dependent and the borrower is facing financial difficulty.

As noted above, the allowance for credit losses on loans does not include an allowance for accrued interest.

Off-Balance-Sheet Credit Exposure, Policy

Liability for Unfunded Lending Commitments

The Company’s unfunded lending commitments are primarily unfunded loan commitments and letters of credit. Expected credit losses for these unfunded lending commitments are calculated over the contractual period during which the Company is exposed to the credit risk. The methodology used to measure credit losses for unfunded lending commitments is the same as the methodology used for loans, however, the estimate of credit risk for unfunded lending commitments takes into consideration the likelihood that funding will occur. The liability for unfunded lending commitments excludes any exposures that are unconditionally cancellable by the Company. The loss estimate is recorded within other liabilities on the consolidated balance sheet. Changes to the liability for unfunded lending commitments are recorded through increases or decreases to the provision for credit losses on the consolidated statements of income.

Direct Financing And Sales Type Leases

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.

Investments In Debt And Equity Securities

Investments in Debt and Equity Securities

The majority of the Company's investment portfolio is comprised of debt securities that 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 are reported in other comprehensive income (loss), a component of stockholders’ equity. Securities are periodically evaluated for credit losses in accordance with the guidance provided in Accounting Standards Codification (ASC) 326. Further discussion of this evaluation is provided in "Allowance for Credit Losses on Available for Sale Debt Securities" below. 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 certain callable debt securities purchased at a premium, the amortization is recorded to the earliest call date. For mortgage and asset-backed securities, prepayment experience is evaluated quarterly to determine if a change in a bond's estimated remaining life is necessary. A corresponding adjustment is then made in the related amortization of premium or discount accretion.

Accrued interest receivable on available for sale debt securities is reported in other assets on the consolidated balance sheet. The Company has elected the practical expedient to exclude the accrued interest from all required disclosures of amortized cost of debt securities. Additionally, an election was made not to measure an allowance for credit losses for accrued interest receivables. Interest accrued but not received is reversed against interest income.

Equity securities include common and preferred stock and are carried at fair value. Certain equity securities do not have readily determinable fair values. The Company has elected to measure these equity securities without a readily determinable fair value 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 equity securities without readily determinable fair values.

Other securities include the Company's investments in Federal Reserve Bank stock and Federal Home Loan Bank stock, equity method investments, and private equity investments. Federal Reserve Bank stock and Federal Home Loan Bank stock are held for debt and regulatory purposes, are carried at cost and are periodically evaluated for impairment. The Company's equity method investments are carried at cost, adjusted to reflect the Company's portion of income, loss, or dividends of the investee. The Company's private equity investments in portfolio concerns, consisting of both debt and equity instruments, are held by the Company’s private equity subsidiary, which is a small business investment company licensed by the Small Business Administration. The Company's private equity investments are carried at fair value in accordance with investment company accounting guidance (ASC 946-10-15), with changes in fair value reported in current income. 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 income 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 transaction pending settlements.

Credit Loss, Financial Instrument

Allowance for Credit Losses on Available for Sale Debt Securities

For available for sale debt securities in an unrealized loss position, 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 more likely than not that it will be required to sell the security before the anticipated recovery. If neither condition is met, and the Company does not expect to recover the amortized cost basis, the Company determines whether the decline in fair value resulted from credit losses or other factors. If the assessment indicates that a credit loss exists, the present value of cash flows expected to be collected is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss has occurred, and an allowance for credit losses is recorded. The allowance for credit losses is limited by the amount that the fair value is less than the amortized cost basis. Any impairment not recorded through the provision for credit losses is recognized in other comprehensive income.

Changes in the allowance for credit losses are recorded as a provision for (or reversal of) credit losses on the consolidated statements of income. Losses are charged against the allowance for credit losses on securities when management believes the uncollectibility of an available for sale security is confirmed or when either of the conditions regarding intent or requirement to sell is met.

Accrued interest receivable on available for sale debt securities is excluded from the estimate of credit losses.

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

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 Federal Reserve Bank 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 20, Resale and Repurchase Agreements.

Premises 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 to 40 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.

Also included in premises and equipment is construction in process, which represents facilities construction projects underway that have not yet been placed into service, as well as the Company's right-of-use leased assets, which are mainly comprised of operating leases for branches, office space, ATM locations, and certain equipment.

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

credit 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. Foreclosed assets are included in other assets on the consolidated balance sheets.

Goodwill and Intangible Assets

Goodwill and intangible assets that have indefinite useful lives, such as property easement intangible assets, are not amortized but are 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, an impairment has occurred and is measured as the amount by which the carrying amount exceeds the reporting unit's fair value. 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 generally 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 its 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.

Additional information about current and deferred income taxes is provided in Note 9, 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, the sales of annuities and certain limited insurance products, and beginning in August 2023, commissions on sales of consumer brokerage transactions and 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. Additionally, the Company originates and sells 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 the Company has 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. From time to time, the Company has monetized its interest rate floors that had previously been designated and qualified as cash flow hedges. In such case, the monetized cash flow hedge is derecognized and the amounts recorded in accumulated other comprehensive income (AOCI) remain in AOCI until the underlying forecasted transaction impacts earnings, unless the forecasted transaction becomes probable of not occurring.

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 17, Fair Value Measurements and Note 19, Derivative Instruments.

Cash flows associated with derivative instruments and their related gains and losses are presented in the consolidated statement of cash flows as operating activities.

Pension Plan

The Company’s pension plan is described in Note 10, Employee Benefit Plans. In accordance with ASU 2017-07, the Company has reported the service cost component of net periodic pension cost 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 other asset or other 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 compensation plan is described in Note 11, 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 stock appreciation rights 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. The Company recognizes forfeitures as a reduction to expense only when they have occurred.

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

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 2023.