Significant Accounting Policies (Notes)	12 Months Ended
Dec. 31, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Business Description The Interpublic Group of Companies, Inc. and subsidiaries (the “Company,” “IPG,” “we,” “us” or “our”) is one of the world’s premier global advertising and marketing services companies. Our agencies create customized marketing programs for clients that range in scale from large global marketers to regional and local clients. Comprehensive global services are critical to effectively serve our multinational and local clients in markets throughout the world, as they seek to build brands, increase sales of their products and services and gain market share. Principles of Consolidation The Consolidated Financial Statements include the accounts of the Company and its consolidated subsidiaries, some of which are not wholly owned. Investments in companies over which we do not have control, but have the ability to exercise significant influence, are accounted for using the equity method of accounting. Investments in companies over which we have neither control nor have the ability to exercise significant influence are recorded at cost, less any impairment, adjusted for subsequent observable price changes. All intercompany accounts and transactions have been eliminated in consolidation. We have consolidated certain entities meeting the definition of variable interest entities, and the inclusion of these entities does not have a material impact on our Consolidated Financial Statements. Basis of Presentation We conduct our business across three reportable segments described in Note 15. The three reportable segments are: Media, Data & Engagement Solutions ("MD&E"), Integrated Advertising & Creativity Led Solutions ("IA&C"), and Specialized Communications & Experiential Solutions ("SC&E"). Cost of services is comprised of the expenses of our revenue-producing operating segments including salaries and related expenses, office and other direct expenses and billable expenses, as well as an allocation of the centrally managed expenses from Corporate and other. Office and other direct expenses include rent expense, professional fees, certain expenses incurred by our staff in servicing our clients and other costs directly attributable to client engagements. Selling, general and administrative expenses are primarily the unallocated expenses from Corporate and other, as disclosed further in Note 15, excluding depreciation and amortization. Depreciation and amortization of the fixed assets and intangible assets of the Company is disclosed as a separate operating expense. Restructuring charges relate to the Company's implementation of cost initiatives to better align our cost structure with our revenue, as discussed further in Note 11. Reclassifications Certain reclassifications and immaterial adjustments have been made to prior-period financial statements to conform to the current-period presentation. Additionally, certain prior period amounts, wherever applicable, have been recast to reflect the transfer of certain agencies between reportable segments. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires us to make judgments, assumptions and estimates that affect the amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the reporting date and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates under different assumptions or conditions. A further decline in macroeconomic conditions or increasing interest rates could have a negative impact on these estimates, including the fair value of certain estimates. Revenue Recognition Our revenues are primarily derived from the planning and execution of multi-channel advertising and communications, marketing services, including public relations, meeting and event production, sports and entertainment marketing, corporate and brand identity, strategic marketing consulting, and providing marketing data and technology services around the world. Most of our client contracts are individually negotiated and, accordingly, the terms of client engagements and the basis on which we earn fees and commissions vary significantly. Our contracts generally provide for termination by either party on relatively short notice, usually 30 to 90 days, although our data management contracts typically have non-cancelable terms of more than one year. Our payment terms vary by client, and the time between invoicing date and due date is typically not significant. We generally have the legally enforceable right to payment for all services provided through the end of the contract or termination date. We recognize revenue when we determine our customer obtains control of promised goods or services, in an amount that reflects the consideration which we expect to receive in exchange for those goods or services. To determine revenue recognition, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue as or when we satisfy the performance obligation. We only apply the five-step model to contracts when it is probable that IPG will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, we assess the goods or services promised within each contract and determine those that are distinct performance obligations. We then assess whether we act as an agent or a principal for each identified performance obligation and include revenue within the transaction price for third-party costs when we determine that we act as principal. We typically do not capitalize costs to obtain a contract as these amounts would generally be recognized over a period of one year or less. Revenue before billable expenses, primarily consisting of fees, commissions and performance incentives, represents the amount of our gross billings excluding billable expenses charged to a client. Generally, our compensation is based on a negotiated fixed price, rate per hour, a retainer, commission or volume. The majority of our fees are recognized over time as services are performed, either utilizing a function of hours incurred and rates per hour, as compared to periodically updated estimates to complete, or ratably over the term of the contract. For certain less-frequent commission-based contracts which contain clauses allowing our clients to terminate the arrangement at any time for no compensation, revenue is recognized at a point in time, typically the date of broadcast or publication. We report revenue net of taxes assessed by governmental authorities that are directly imposed on our revenue-producing transactions. Contractual arrangements with clients may also include performance incentive provisions designed to link a portion of our revenue to our performance relative to mutually agreed-upon qualitative and/or quantitative metrics. Performance incentives are treated as variable consideration which is estimated at contract inception and included in revenue based on the most likely amount earned out of a range of potential outcomes. Our estimates are based on a combination of historical award experience, anticipated performance and our best judgment. These estimates are updated on a periodic basis and are not expected to result in a reversal of a significant amount of the cumulative revenue recognized. The predominant component of billable expenses are third-party vendor costs incurred for performance obligations where we have determined that we are acting as principal. These third-party expenses are generally billed back to our clients. Billable expenses also includes incidental costs incurred in the performance of our services including airfare, mileage, hotel stays, out-of-town meals and telecommunication charges. We record these billable expenses within total revenue with a corresponding offset to operating expenses. In international markets, we may receive rebates or credits from vendors based on transactions entered into on behalf of clients. Rebates and credits are remitted back to our clients in accordance with our contractual requirements or may be retained by us based on the terms of a particular client contract and local law. Amounts owed back to clients are recorded as a liability and amounts retained by us are recorded as revenue when earned. In certain international markets, our media contracts may allow clients to terminate our arrangement at any time for no compensation to the extent that media has not yet run. For those contracts, we do not recognize revenue until the media runs which is the point in time at which we have a legally enforceable right to compensation. In the normal course of business, certain agencies may enter into agreements with media suppliers to purchase an agreed value of media within a fixed timeframe. By entering into these agreements, the agency is taking a risk and may be required to pay a portion or all of the agreed value ahead of media being run. In order to participate in these arrangements and receive an agreed additional benefit from the agency, clients are required to contractually opt in. Performance Obligations Our client contracts may include various goods and services that are capable of being distinct, are distinct within the context of the contract and are therefore accounted for as separate performance obligations. We allocate revenue to each performance obligation in the contract at inception based on its relative standalone selling price. Our advertising businesses include a wide range of services that involve the creation of an advertising idea, concept, campaign, or marketing strategy in order to promote the client’s brand ("creative services"), and to act as an agent to facilitate the production of advertisements by third-party suppliers ("production services”). Our clients can contract us to perform one or both of these services, as they can derive stand-alone benefit from each. Production services can include formatting creative material for different media and communication mediums including digital, large-scale reproduction such as printing and adaptation services, talent engagement and acquisition, television and radio production, and outdoor billboard production. Our contracts that include both services are typically explicit in the description of which activities constitute the creative advertising services and those that constitute the production services. Both the creative and production services are sold separately, the client can derive utility from each service on its own, we do not provide a significant service of integrating these activities into a bundle, the services do not significantly modify one another, and the services are not highly interrelated or interdependent. As such, we typically identify two performance obligations in the assessment of our advertising contracts. Our media businesses include services to formulate strategic media plans ("media planning services") and to act as an agent to purchase media (e.g. television and radio spots, outdoor advertising, digital banners, etc.) from vendors on our clients' behalf ("media buying services"). Our contracts that include both services are typically explicit in the description of which activities constitute the planning services and those that constitute the buying services. Both the planning and buying services are sold separately, the client can derive utility from each service on its own, we do not provide a significant service of integrating these activities into a bundle, the services do not significantly modify one another, and the services are not highly interrelated or interdependent. As such, we typically identify two performance obligations in the assessment of our media contracts. Our events businesses include creative services related to the conception and planning of custom marketing events as well as activation services which entail the carrying out of the event, including, but not limited to, set-up, design and staffing. Additionally, our public relations businesses include a broad range of services, such as strategic planning, social media strategy and the monitoring and development of communication strategies, among others. While our contracts in these businesses may include some or all of these services, we typically identify only one performance obligation in the assessment of our events and public relations contracts as we provide a significant service of integrating the individual services into a combined service for which the customer has contracted. Our data and technology services businesses include data management, data and data strategy, identity resolution, and measurement and analytics products and services. While our contracts in these businesses may include some or all of these services, we typically identify each product and service as an individual performance obligation. We have elected not to disclose information about remaining performance obligations that have original expected durations of one year or less. The majority of our contracts are for periods of one year or less with the exception of our data management contracts. Principal vs. Agent When a third-party is involved in the delivery of our services to the client, we assess whether or not we are acting as a principal or an agent in the arrangement. The assessment is based on whether we control the specified services at any time before they are transferred to the customer. We have determined that in our events and public relations businesses, we generally act as a principal as our agencies provide a significant service of integrating goods or services provided by third parties into the specified deliverable to our clients. In addition, we have determined that we are responsible for the performance of the third-party suppliers, which are combined with our own services, before transferring those services to the customer. We have also determined that we act as principal when providing creative services and media planning services, as we perform a significant integration service in these transactions. For performance obligations in which we act as principal, we record the gross amount billed to the customer within total revenue and the related incremental direct costs incurred as billable expenses. In the vast majority of our business, when a third-party is involved in the production of an advertising campaign and for media buying services, we have determined that we act as the agent and are solely arranging for the third-party suppliers to provide services to the customer. Specifically, we do not control the specified services before transferring those services to the customer, we are not primarily responsible for the performance of the third-party services, nor can we redirect those services to fulfill any other contracts. We do not have inventory risk or discretion in establishing pricing in our contracts with customers. For performance obligations for which we act as the agent, we record our revenue as the net amount of our gross billings less amounts remitted to third parties. Cash and Cash Equivalents Cash equivalents are highly liquid investments, which include certificates of deposit, government securities, commercial paper and time deposits with original maturities of three months or less at the time of purchase and are stated at estimated fair value, which approximates cost. Cash is maintained at multiple high-credit-quality financial institutions. Allowance for Expected Credit Losses The allowance for credit losses on expected future uncollectible accounts receivable is estimated based on the aging of accounts receivable, reviews of client credit reports, industry trends and economic indicators, as well as reviews of recent payment history for specific customers. The estimate is based largely on a formula-driven calculation but is supplemented with economic indicators and knowledge of potential write-offs of specific client accounts. Accounts Receivable, Billable to Clients Accounts receivable, billable to clients are primarily comprised of production and media costs that have been incurred but have not yet been billed to clients, as well as fees that have been earned which have not yet been billed to clients. Unbilled amounts are presented in accounts receivable, billable to clients regardless of whether they relate to our fees or production and media costs. A provision is made for unrecoverable costs as deemed appropriate. Accounts Payable Accounts payable includes all operating payables, including those related to all media and production costs. These payables are due within one year. Investments Equity investments with readily determinable fair values, other than those accounted for using the equity method of accounting, will be measured at fair value. We regularly review our investments to determine whether a significant event or change in circumstances has occurred that may impact the fair value of each investment, with changes to fair value recorded in earnings. We evaluate fair value based on specific information (valuation methodologies, estimates of appraisals, financial statements, etc.) in addition to quoted market price, if available. We consider all known quantitative and qualitative factors in determining if a decline in value of an investment has occurred. Derivatives We are exposed to market risk related to interest rates, foreign currency rates and certain balance sheet items. From time to time we enter into derivative instruments for risk management purposes, and not for speculative purposes. All derivative instruments are recorded at fair value on our balance sheet. Changes in fair value are immediately included in earnings if the derivatives are not designated as a hedge instrument or if the derivatives do not qualify as effective hedges. For derivatives designated as hedge instruments, we evaluate for hedge accounting both at inception and throughout the hedge period. If a derivative is designated as a fair value hedge, then changes in the fair value of the derivative are offset against the changes in the fair value of the underlying hedged item. If a derivative is designated as a cash flow hedge, then the changes in the fair value of the derivative are recognized as a component of accumulated other comprehensive income and subsequently reclassified to earnings in our Consolidated Statement of Operations in the same period as the underlying hedged transaction affects earnings. If a derivative is a net investment hedge, then the changes in the fair value of the derivative are recognized in other comprehensive income in the same period as the change in fair value of the underlying hedged foreign investment. Property and Equipment Furniture, equipment, leasehold improvements and buildings are stated at cost, net of accumulated depreciation. Furniture and equipment are depreciated generally using the straight-line method over the estimated useful lives of the related assets, which range from 3 to 7 years for furniture and equipment, 10 to 35 years for buildings and the shorter of the useful life or the remaining lease term for leasehold improvements. Land is stated at cost and is not depreciated. We capitalize certain internal and external costs incurred to acquire or create internal use software, principally related to our enterprise resource planning (“ERP”) systems. Our ERP systems are stated at cost, net of accumulated amortization, and are amortized using the straight-line method over 10 years. All other internal use computer software are stated at cost, net of accumulated amortization and are amortized using the straight-line method over the estimated useful lives of the related assets, which range from 3 to 7 years. Leases As of December 31, 2023, we do not have a material amount of finance leases and the majority of our operating leases, for which we serve as the lessee, consist primarily of real-estate property for our offices around the world. Both the right-of-use asset and lease liability are measured at the present value of the future lease payments, with the asset being subject to adjustments such as initial direct costs, prepaid lease payments, and lease incentives. Many of our leases provide for renewal and/or termination options, as well as escalation clauses, which are also factored into our lease payments when appropriate. The discount rate used to measure the lease asset and liability is determined at the beginning of the lease term using the rate implicit in the lease, if readily determinable, or using the Company's collateralized credit-adjusted borrowing rate. Goodwill and Other Intangible Assets We account for our business combinations using the acquisition accounting method, which requires us to determine the fair value of net assets acquired and the related goodwill and other intangible assets. Determining the fair value of assets acquired and liabilities assumed requires management's judgment and involves the use of significant estimates, including projections of future cash inflows and outflows, discount rates, asset lives and market multiples. Considering the characteristics of advertising, specialized marketing and communication services companies, our acquisitions usually do not have significant amounts of tangible assets, as the principal asset we typically acquire is creative talent. As a result, a substantial portion of the purchase price is allocated to goodwill and other intangible assets. We review goodwill as of October 1st each year and whenever events or significant changes in circumstances indicate that the carrying value may not be recoverable. We evaluate the recoverability of goodwill at a reporting unit level. We have 10 reporting units that were subject to the 2023 annual impairment testing. Our annual impairment review as of October 1, 2023 did not result in an impairment charge for any of our reporting units. Intangible assets with indefinite useful lives are not amortized but are evaluated for impairment annually or more frequently if events or changes in circumstances indicate that impairment may exist. The Company first assesses qualitative factors to determine whether it is necessary to perform a quantitative impairment test for indefinite-lived intangible assets. Impairment exists if the fair value of the indefinite-lived intangible asset is less than the carrying value. The determination of fair value is based on the relief from royalty method of the income approach, which models the cash flows from indefinite-lived intangibles assuming royalties were received under a licensing arrangement. This discounted cash flow analysis includes assumptions related to forecasted future revenues attributable to indefinite-lived intangibles, royalty rates and risk-adjusted discount rates. If the carrying value of an indefinite-lived intangible asset exceeds its estimated fair value, the indefinite-lived intangible asset is considered impaired, and an impairment loss will be recognized in an amount equal to the excess of the carrying value over the fair value. Based on this analysis, for the indefinite lived-intangible asset for which we performed a quantitative impairment test as of October 1, 2023, we concluded that it was not impaired because its fair value was in excess of its carrying value. For reporting units not included in the qualitative assessment, or for any reporting units identified in the qualitative assessment as "more likely than not" that the fair value is less than its carrying value, the quantitative impairment test is performed. For our annual impairment test, we compare the respective fair value of our reporting units' equity to the carrying value of their net assets. The sum of the fair values of all our reporting units is also reconciled to our current market capitalization plus an estimated control premium. Goodwill allocated to a reporting unit whose fair value is equal to or greater than its carrying value is not impaired, and no further testing is required. Should the carrying amount for a reporting unit exceed its fair value, then the quantitative impairment test is failed and impaired goodwill is written down to its fair value with a charge to expense in the period the impairment is identified. The fair value of each reporting unit for 2023 and 2022 was estimated using a combination of the income approach, which incorporates the use of the discounted cash flow method, and the market approach, which incorporates the use of earnings and revenue multiples based on market data. We review intangible assets with definite lives subject to amortization whenever events or circumstances indicate that a carrying amount of an asset may not be recoverable. Recoverability of these assets is determined by comparing the carrying value of these assets to the estimated undiscounted future cash flows expected to be generated by these asset groups. These asset groups are impaired when their carrying value exceeds their fair value. Impaired intangible assets with definite lives subject to amortization are written down to their fair value with a charge to expense in the period the impairment is identified. Intangible assets with definite lives are amortized on a straight-line basis with estimated useful lives generally between 7 and 15 years. Events or circumstances that might require impairment testing include the loss of a significant client, the identification of other impaired assets within a reporting unit, loss of key personnel, the disposition of a significant portion of a reporting unit, significant decline in stock price or a significant adverse change in business climate or regulations. Foreign Currencies The functional currency of our foreign operations is generally their respective local currency. Assets and liabilities are translated at the exchange rates in effect at the balance sheet date, and revenues and expenses are translated at the average exchange rates during the period presented. The resulting translation adjustments are recorded as a component of accumulated other comprehensive loss in the stockholders’ equity section of our Consolidated Balance Sheets. Currency transaction gains or losses primarily arising from transactions in currencies other than the functional currency are included in office and general expenses. Foreign currency transactions resulted in a pre-tax loss of $5.7 for the year ended December 31, 2023, a pre-tax gain of $2.5 for the year ended December 31, 2022, and a pre-tax loss of $5.0 for the year ended December 31, 2021. We monitor the currencies of countries in which we operate in order to determine if the country should be considered a highly inflationary environment. A currency is determined to be highly inflationary when there is cumulative inflation of approximately 100% or more over a three-year period. If this occurs the functional currency of that country is changed to our reporting currency, the U.S. Dollar, and foreign exchange gains or losses are recognized on all monetary transactions, assets and liabilities in currencies other than the U.S. Dollar until the currency is no longer considered highly inflationary. Income Taxes The provision for income taxes includes U.S. federal, state, local and foreign taxes. Income taxes are accounted for under the liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences of temporary differences between the financial statement carrying amounts and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the year in which the temporary differences are expected to be reversed. We evaluate the realizability of our deferred tax assets and establish a valuation allowance when it is “more likely than not” that all or a portion of the deferred tax assets will not be realized. We evaluate our tax positions using the “more likely than not” recognition threshold and then apply a measurement assessment to those positions that meet the recognition threshold. The factors used in assessing valuation allowances include all available evidence, such as past operating results, estimates of future taxable income and the feasibility of tax planning strategies. We have established tax reserves that we believe to be adequate in relation to the potential for additional assessments in each of the jurisdictions in which we are subject to taxation. We regularly assess the likelihood of additional tax assessments in those jurisdictions and adjust our reserves as additional information or events require. Redeemable Non-controlling Interests Many of our acquisitions include provisions under which the non-controlling equity owners can require us to purchase additional interests in a subsidiary at their discretion. Payments for these redeemable non-controlling interests may be contingent on projected operating performance and satisfying other conditions specified in the related agreements. These payments are also subject to revision in accordance with the terms of the agreements. We record these redeemable non-controlling interests in “mezzanine equity” in our Consolidated Balance Sheets. Each reporting period, redeemable non-controlling interests are reported at their estimated redemption value, but not less than their initial fair value. Any adjustment to the redemption value above initial value prior to exercise will also impact retained earnings but will not impact net income. Adjustments as a result of currency translation will affect the redeemable non-controlling interest balance, but do not impact retained earnings or additional paid-in capital. Earnings Per Share (“EPS”) Basic EPS available to IPG common stockholders equals net income available to IPG common stockholders divided by the weighted-average number of common shares outstanding for the applicable period. Diluted EPS equals net income available to IPG common stockholders divided by the weighted-average number of common shares outstanding, plus any additional common shares that would have been outstanding if potentially dilutive shares had been issued. Diluted EPS reflect the potential dilution that would occur if certain potentially dilutive securities were exercised. The potential issuance of common stock is assumed to occur at the beginning of the year (or at the time of issuance of the potentially dilutive instrument, if later) and the incremental shares are included using the treasury stock method. The proceeds utilized in applying the treasury stock method consist of the amount, if any, to be paid upon exercise and, as it relates to stock-based compensation, the amount of compensation cost attributed to future service not yet recognized. These proceeds are then assumed to be used to purchase common stock at the average market price of our stock during the period. The incremental shares (difference between the shares assumed to be issued and the shares assumed to be purchased), to the extent they would have been dilutive, are included in the denominator of the diluted EPS calculation. We may be required to calculate basic EPS using the two-class method as a result of our redeemable non-controlling interests. To the extent that the redemption value increases and exceeds the then-current fair value of a redeemable non-controlling interest, net income available to IPG common stockholders (used to calculate EPS) could be negatively impacted by that increase, subject to certain limitations. The partial or full recovery of any reductions to net income available to IPG common stockholders (used to calculate EPS) is limited to any cumulative prior-period reductions. For the years ended December 31, 2023, 2022 and 2021, there was no impact to EPS for adjustments related to our redeemable non-controlling interests. Pension and Postretirement Benefits We have pension and postretirement benefit plans covering certain domestic and international employees. We use various actuarial methods and assumptions in determining our net pension and postretirement benefit costs and obligations, including the discount rate used to determine the present value of future benefits, expected long-term rate of return on plan assets and healthcare cost trend rates. The overfunded or underfunded status of our pension and postretirement benefit plans is recorded on our Consolidated Balance Sheet. Stock-Based Compensation Compensation costs related to share-based transactions, including employee stock options, are recognized in the Consolidated Financial Statements based on fair value. Stock-based compensation expense is generally recognized ratably over the requisite service period based on the estimated grant-date fair value, net of estimated forfeitures. Treasury Stock We account for repurchased common stock under the cost method and include such treasury stock as a component of our Consolidated Statements of Stockholders' Equity. Upon retirement, we reduce common stock for the par value of the shares being retired and the excess of the cost of the shares over par value as a reduction to APIC, to the extent there is APIC in the same class of stock, and any remaining amount to retained earnings. These retired shares remain authorized but unissued. In October 2023, we retired 9.3 shares of our treasury stock, which resulted in a reduction in common stock of $0.9, treasury stock of $340.4 and APIC of $339.5. In October 2022, we retired 7.2 shares of our treasury stock, which resulted in a reduction in common stock of $0.7, treasury stock of $199.9 and APIC of $199.2. During 2021, there was no significant treasury stock activity due to the suspension of the share repurchase program.
Treasury Stock [Text Block]	Treasury Stock We account for repurchased common stock under the cost method and include such treasury stock as a component of our Consolidated Statements of Stockholders' Equity. Upon retirement, we reduce common stock for the par value of the shares being retired and the excess of the cost of the shares over par value as a reduction to APIC, to the extent there is APIC in the same class of stock, and any remaining amount to retained earnings. These retired shares remain authorized but unissued. In October 2023, we retired 9.3 shares of our treasury stock, which resulted in a reduction in common stock of $0.9, treasury stock of $340.4 and APIC of $339.5. In October 2022, we retired 7.2 shares of our treasury stock, which resulted in a reduction in common stock of $0.7, treasury stock of $199.9 and APIC of $199.2. During 2021, there was no significant treasury stock activity due to the suspension of the share repurchase program.

The Interpublic Group of Companies, Inc. and subsidiaries (the “Company,” “IPG,” “we,” “us” or “our”) is one of the world’s premier global advertising and marketing services companies. Our agencies create customized marketing programs for clients that range in scale from large global marketers to regional and local clients. Comprehensive global services are critical to effectively serve our multinational and local clients in markets throughout the world, as they seek to build brands, increase sales of their products and services and gain market share.

The Consolidated Financial Statements include the accounts of the Company and its consolidated subsidiaries, some of which are not wholly owned. Investments in companies over which we do not have control, but have the ability to exercise significant influence, are accounted for using the equity method of accounting. Investments in companies over which we have neither control nor have the ability to exercise significant influence are recorded at cost, less any impairment, adjusted for subsequent observable price changes. All intercompany accounts and transactions have been eliminated in consolidation.

Cost of services is comprised of the expenses of our revenue-producing operating segments including salaries and related expenses, office and other direct expenses and billable expenses, as well as an allocation of the centrally managed expenses from Corporate and other. Office and other direct expenses include rent expense, professional fees, certain expenses incurred by our staff in servicing our clients and other costs directly attributable to client engagements.

Certain reclassifications and immaterial adjustments have been made to prior-period financial statements to conform to the current-period presentation. Additionally, certain prior period amounts, wherever applicable, have been recast to reflect the transfer of certain agencies between reportable segments.

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) requires us to make judgments, assumptions and estimates that affect the amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the reporting date and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates under different assumptions or conditions. A further decline in macroeconomic conditions or increasing interest rates could have a negative impact on these estimates, including the fair value of certain estimates.

Our revenues are primarily derived from the planning and execution of multi-channel advertising and communications, marketing services, including public relations, meeting and event production, sports and entertainment marketing, corporate and brand identity, strategic marketing consulting, and providing marketing data and technology services around the world.

Most of our client contracts are individually negotiated and, accordingly, the terms of client engagements and the basis on which we earn fees and commissions vary significantly. Our contracts generally provide for termination by either party on relatively short notice, usually 30 to 90 days, although our data management contracts typically have non-cancelable terms of

We recognize revenue when we determine our customer obtains control of promised goods or services, in an amount that reflects the consideration which we expect to receive in exchange for those goods or services. To determine revenue recognition, we perform the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue as or when we satisfy the performance obligation. We only apply the five-step model to contracts when it is probable that IPG will collect the consideration it is entitled to in exchange for the goods or services it transfers to the customer. At contract inception, we assess the goods or services promised within each contract and determine those that are distinct performance obligations. We then assess whether we act as an agent or a principal for each identified performance obligation and include revenue within the transaction price for third-party costs when we determine that we act as principal. We typically do not capitalize costs to obtain a contract as these amounts would generally be recognized over a period of one year or less.

Revenue before billable expenses, primarily consisting of fees, commissions and performance incentives, represents the amount of our gross billings excluding billable expenses charged to a client. Generally, our compensation is based on a negotiated fixed price, rate per hour, a retainer, commission or volume. The majority of our fees are recognized over time as services are performed, either utilizing a function of hours incurred and rates per hour, as compared to periodically updated estimates to complete, or ratably over the term of the contract. For certain less-frequent commission-based contracts which contain clauses allowing our clients to terminate the arrangement at any time for no compensation, revenue is recognized at a point in time, typically the date of broadcast or publication. We report revenue net of taxes assessed by governmental authorities that are directly imposed on our revenue-producing transactions.

Contractual arrangements with clients may also include performance incentive provisions designed to link a portion of our revenue to our performance relative to mutually agreed-upon qualitative and/or quantitative metrics. Performance incentives are treated as variable consideration which is estimated at contract inception and included in revenue based on the most likely amount earned out of a range of potential outcomes. Our estimates are based on a combination of historical award experience, anticipated performance and our best judgment. These estimates are updated on a periodic basis and are not expected to result in a reversal of a significant amount of the cumulative revenue recognized.

The predominant component of billable expenses are third-party vendor costs incurred for performance obligations where we have determined that we are acting as principal. These third-party expenses are generally billed back to our clients. Billable expenses also includes incidental costs incurred in the performance of our services including airfare, mileage, hotel stays, out-of-town meals and telecommunication charges. We record these billable expenses within total revenue with a corresponding offset to operating expenses.

In international markets, we may receive rebates or credits from vendors based on transactions entered into on behalf of clients. Rebates and credits are remitted back to our clients in accordance with our contractual requirements or may be retained by us based on the terms of a particular client contract and local law. Amounts owed back to clients are recorded as a liability and amounts retained by us are recorded as revenue when earned.

In certain international markets, our media contracts may allow clients to terminate our arrangement at any time for no compensation to the extent that media has not yet run. For those contracts, we do not recognize revenue until the media runs which is the point in time at which we have a legally enforceable right to compensation.

In the normal course of business, certain agencies may enter into agreements with media suppliers to purchase an agreed value of media within a fixed timeframe. By entering into these agreements, the agency is taking a risk and may be required to pay a portion or all of the agreed value ahead of media being run. In order to participate in these arrangements and receive an agreed additional benefit from the agency, clients are required to contractually opt in.

Our client contracts may include various goods and services that are capable of being distinct, are distinct within the context of the contract and are therefore accounted for as separate performance obligations. We allocate revenue to each performance obligation in the contract at inception based on its relative standalone selling price.

Our advertising businesses include a wide range of services that involve the creation of an advertising idea, concept, campaign, or marketing strategy in order to promote the client’s brand ("creative services"), and to act as an agent to facilitate the production of advertisements by third-party suppliers ("production services”). Our clients can contract us to perform one or both of these services, as they can derive stand-alone benefit from each. Production services can include formatting creative material for different media and communication mediums including digital, large-scale reproduction such as printing and

adaptation services, talent engagement and acquisition, television and radio production, and outdoor billboard production. Our contracts that include both services are typically explicit in the description of which activities constitute the creative advertising services and those that constitute the production services. Both the creative and production services are sold separately, the client can derive utility from each service on its own, we do not provide a significant service of integrating these activities into a bundle, the services do not significantly modify one another, and the services are not highly interrelated or interdependent. As such, we typically identify two performance obligations in the assessment of our advertising contracts.

Our media businesses include services to formulate strategic media plans ("media planning services") and to act as an agent to purchase media (e.g. television and radio spots, outdoor advertising, digital banners, etc.) from vendors on our clients' behalf ("media buying services"). Our contracts that include both services are typically explicit in the description of which activities constitute the planning services and those that constitute the buying services. Both the planning and buying services are sold separately, the client can derive utility from each service on its own, we do not provide a significant service of integrating these activities into a bundle, the services do not significantly modify one another, and the services are not highly interrelated or interdependent. As such, we typically identify two performance obligations in the assessment of our media contracts.

Our events businesses include creative services related to the conception and planning of custom marketing events as well as activation services which entail the carrying out of the event, including, but not limited to, set-up, design and staffing. Additionally, our public relations businesses include a broad range of services, such as strategic planning, social media strategy and the monitoring and development of communication strategies, among others. While our contracts in these businesses may include some or all of these services, we typically identify only one performance obligation in the assessment of our events and public relations contracts as we provide a significant service of integrating the individual services into a combined service for which the customer has contracted.

Our data and technology services businesses include data management, data and data strategy, identity resolution, and measurement and analytics products and services. While our contracts in these businesses may include some or all of these services, we typically identify each product and service as an individual performance obligation.

When a third-party is involved in the delivery of our services to the client, we assess whether or not we are acting as a principal or an agent in the arrangement. The assessment is based on whether we control the specified services at any time before they are transferred to the customer. We have determined that in our events and public relations businesses, we generally act as a principal as our agencies provide a significant service of integrating goods or services provided by third parties into the specified deliverable to our clients. In addition, we have determined that we are responsible for the performance of the third-party suppliers, which are combined with our own services, before transferring those services to the customer. We have also determined that we act as principal when providing creative services and media planning services, as we perform a significant integration service in these transactions. For performance obligations in which we act as principal, we record the gross amount billed to the customer within total revenue and the related incremental direct costs incurred as billable expenses.

In the vast majority of our business, when a third-party is involved in the production of an advertising campaign and for media buying services, we have determined that we act as the agent and are solely arranging for the third-party suppliers to provide services to the customer. Specifically, we do not control the specified services before transferring those services to the customer, we are not primarily responsible for the performance of the third-party services, nor can we redirect those services to fulfill any other contracts. We do not have inventory risk or discretion in establishing pricing in our contracts with customers. For performance obligations for which we act as the agent, we record our revenue as the net amount of our gross billings less amounts remitted to third parties.

Cash equivalents are highly liquid investments, which include certificates of deposit, government securities, commercial paper and time deposits with original maturities of three months or less at the time of purchase and are stated at estimated fair value, which approximates cost. Cash is maintained at multiple high-credit-quality financial institutions.

The allowance for credit losses on expected future uncollectible accounts receivable is estimated based on the aging of accounts receivable, reviews of client credit reports, industry trends and economic indicators, as well as reviews of recent payment history for specific customers. The estimate is based largely on a formula-driven calculation but is supplemented with economic indicators and knowledge of potential write-offs of specific client accounts.

Accounts receivable, billable to clients are primarily comprised of production and media costs that have been incurred but have not yet been billed to clients, as well as fees that have been earned which have not yet been billed to clients. Unbilled amounts are presented in accounts receivable, billable to clients regardless of whether they relate to our fees or production and media costs. A provision is made for unrecoverable costs as deemed appropriate.

Equity investments with readily determinable fair values, other than those accounted for using the equity method of accounting, will be measured at fair value. We regularly review our investments to determine whether a significant event or change in circumstances has occurred that may impact the fair value of each investment, with changes to fair value recorded in earnings. We evaluate fair value based on specific information (valuation methodologies, estimates of appraisals, financial statements, etc.) in addition to quoted market price, if available. We consider all known quantitative and qualitative factors in determining if a decline in value of an investment has occurred.

We are exposed to market risk related to interest rates, foreign currency rates and certain balance sheet items. From time to time we enter into derivative instruments for risk management purposes, and not for speculative purposes. All derivative instruments are recorded at fair value on our balance sheet. Changes in fair value are immediately included in earnings if the derivatives are not designated as a hedge instrument or if the derivatives do not qualify as effective hedges. For derivatives designated as hedge instruments, we evaluate for hedge accounting both at inception and throughout the hedge period. If a derivative is designated as a fair value hedge, then changes in the fair value of the derivative are offset against the changes in the fair value of the underlying hedged item. If a derivative is designated as a cash flow hedge, then the changes in the fair value of the derivative are recognized as a component of accumulated other comprehensive income and subsequently reclassified to earnings in our Consolidated Statement of Operations in the same period as the underlying hedged transaction affects earnings. If a derivative is a net investment hedge, then the changes in the fair value of the derivative are recognized in other comprehensive income in the same period as the change in fair value of the underlying hedged foreign investment.

Furniture, equipment, leasehold improvements and buildings are stated at cost, net of accumulated depreciation. Furniture and equipment are depreciated generally using the straight-line method over the estimated useful lives of the related assets, which range from 3 to 7 years for furniture and equipment, 10 to 35 years for buildings and the shorter of the useful life or the remaining lease term for leasehold improvements. Land is stated at cost and is not depreciated.

We capitalize certain internal and external costs incurred to acquire or create internal use software, principally related to our enterprise resource planning (“ERP”) systems. Our ERP systems are stated at cost, net of accumulated amortization, and are amortized using the straight-line method over 10 years. All other internal use computer software are stated at cost, net of accumulated amortization and are amortized using the straight-line method over the estimated useful lives of the related assets, which range from 3 to 7 years.

As of December 31, 2023, we do not have a material amount of finance leases and the majority of our operating leases, for which we serve as the lessee, consist primarily of real-estate property for our offices around the world. Both the right-of-use asset and lease liability are measured at the present value of the future lease payments, with the asset being subject to adjustments such as initial direct costs, prepaid lease payments, and lease incentives. Many of our leases provide for renewal and/or termination options, as well as escalation clauses, which are also factored into our lease payments when appropriate. The discount rate used to measure the lease asset and liability is determined at the beginning of the lease term using the rate implicit in the lease, if readily determinable, or using the Company's collateralized credit-adjusted borrowing rate.

We account for our business combinations using the acquisition accounting method, which requires us to determine the fair value of net assets acquired and the related goodwill and other intangible assets. Determining the fair value of assets acquired and liabilities assumed requires management's judgment and involves the use of significant estimates, including projections of

future cash inflows and outflows, discount rates, asset lives and market multiples. Considering the characteristics of advertising, specialized marketing and communication services companies, our acquisitions usually do not have significant amounts of tangible assets, as the principal asset we typically acquire is creative talent. As a result, a substantial portion of the purchase price is allocated to goodwill and other intangible assets.

We review goodwill as of October 1st each year and whenever events or significant changes in circumstances indicate that the carrying value may not be recoverable. We evaluate the recoverability of goodwill at a reporting unit level. We have 10 reporting units that were subject to the 2023 annual impairment testing. Our annual impairment review as of October 1, 2023 did not result in an impairment charge for any of our reporting units.

Intangible assets with indefinite useful lives are not amortized but are evaluated for impairment annually or more frequently if events or changes in circumstances indicate that impairment may exist. The Company first assesses qualitative factors to determine whether it is necessary to perform a quantitative impairment test for indefinite-lived intangible assets. Impairment exists if the fair value of the indefinite-lived intangible asset is less than the carrying value. The determination of fair value is based on the relief from royalty method of the income approach, which models the cash flows from indefinite-lived intangibles assuming royalties were received under a licensing arrangement. This discounted cash flow analysis includes assumptions related to forecasted future revenues attributable to indefinite-lived intangibles, royalty rates and risk-adjusted discount rates. If the carrying value of an indefinite-lived intangible asset exceeds its estimated fair value, the indefinite-lived intangible asset is considered impaired, and an impairment loss will be recognized in an amount equal to the excess of the carrying value over the fair value. Based on this analysis, for the indefinite lived-intangible asset for which we performed a quantitative impairment test as of October 1, 2023, we concluded that it was not impaired because its fair value was in excess of its carrying value.

For reporting units not included in the qualitative assessment, or for any reporting units identified in the qualitative assessment as "more likely than not" that the fair value is less than its carrying value, the quantitative impairment test is performed. For our annual impairment test, we compare the respective fair value of our reporting units' equity to the carrying value of their net assets. The sum of the fair values of all our reporting units is also reconciled to our current market capitalization plus an estimated control premium. Goodwill allocated to a reporting unit whose fair value is equal to or greater than its carrying value is not impaired, and no further testing is required. Should the carrying amount for a reporting unit exceed its fair value, then the quantitative impairment test is failed and impaired goodwill is written down to its fair value with a charge to expense in the period the impairment is identified.

We review intangible assets with definite lives subject to amortization whenever events or circumstances indicate that a carrying amount of an asset may not be recoverable. Recoverability of these assets is determined by comparing the carrying value of these assets to the estimated undiscounted future cash flows expected to be generated by these asset groups. These asset groups are impaired when their carrying value exceeds their fair value. Impaired intangible assets with definite lives subject to amortization are written down to their fair value with a charge to expense in the period the impairment is identified. Intangible assets with definite lives are amortized on a straight-line basis with estimated useful lives generally between 7 and 15 years. Events or circumstances that might require impairment testing include the loss of a significant client, the identification of other impaired assets within a reporting unit, loss of key personnel, the disposition of a significant portion of a reporting unit, significant decline in stock price or a significant adverse change in business climate or regulations.

The functional currency of our foreign operations is generally their respective local currency. Assets and liabilities are translated at the exchange rates in effect at the balance sheet date, and revenues and expenses are translated at the average exchange rates during the period presented. The resulting translation adjustments are recorded as a component of accumulated other comprehensive loss in the stockholders’ equity section of our Consolidated Balance Sheets. Currency transaction gains or losses primarily arising from transactions in currencies other than the functional currency are included in office and general expenses. Foreign currency transactions resulted in a pre-tax loss of $5.7 for the year ended December 31, 2023, a pre-tax gain of $2.5 for the year ended December 31, 2022, and a pre-tax loss of $5.0 for the year ended December 31, 2021.

We monitor the currencies of countries in which we operate in order to determine if the country should be considered a highly inflationary environment. A currency is determined to be highly inflationary when there is cumulative inflation of approximately 100% or more over a three-year period. If this occurs the functional currency of that country is changed to our reporting currency, the U.S. Dollar, and foreign exchange gains or losses are recognized on all monetary transactions, assets and liabilities in currencies other than the U.S. Dollar until the currency is no longer considered highly inflationary.

The provision for income taxes includes U.S. federal, state, local and foreign taxes. Income taxes are accounted for under the liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences of temporary differences between the financial statement carrying amounts and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the year in which the temporary differences are expected to be reversed. We evaluate the realizability of our deferred tax assets and establish a valuation allowance when it is “more likely than not” that all or a portion of the deferred tax assets will not be realized. We evaluate our tax positions using the “more likely than not” recognition threshold and then apply a measurement assessment to those positions that meet the recognition threshold. The factors used in assessing valuation allowances include all available evidence, such as past operating results, estimates of future taxable income and the feasibility of tax planning strategies. We have established tax reserves that we believe to be adequate in relation to the potential for additional assessments in each of the jurisdictions in which we are subject to taxation. We regularly assess the likelihood of additional tax assessments in those jurisdictions and adjust our reserves as additional information or events require.

Many of our acquisitions include provisions under which the non-controlling equity owners can require us to purchase additional interests in a subsidiary at their discretion. Payments for these redeemable non-controlling interests may be contingent on projected operating performance and satisfying other conditions specified in the related agreements. These payments are also subject to revision in accordance with the terms of the agreements. We record these redeemable non-controlling interests in “mezzanine equity” in our Consolidated Balance Sheets. Each reporting period, redeemable non-controlling interests are reported at their estimated redemption value, but not less than their initial fair value. Any adjustment to the redemption value above initial value prior to exercise will also impact retained earnings but will not impact net income. Adjustments as a result of currency translation will affect the redeemable non-controlling interest balance, but do not impact retained earnings or additional paid-in capital.

Basic EPS available to IPG common stockholders equals net income available to IPG common stockholders divided by the weighted-average number of common shares outstanding for the applicable period. Diluted EPS equals net income available to IPG common stockholders divided by the weighted-average number of common shares outstanding, plus any additional common shares that would have been outstanding if potentially dilutive shares had been issued.

Diluted EPS reflect the potential dilution that would occur if certain potentially dilutive securities were exercised. The potential issuance of common stock is assumed to occur at the beginning of the year (or at the time of issuance of the potentially dilutive instrument, if later) and the incremental shares are included using the treasury stock method. The proceeds utilized in applying the treasury stock method consist of the amount, if any, to be paid upon exercise and, as it relates to stock-based compensation, the amount of compensation cost attributed to future service not yet recognized. These proceeds are then assumed to be used to purchase common stock at the average market price of our stock during the period. The incremental shares (difference between the shares assumed to be issued and the shares assumed to be purchased), to the extent they would have been dilutive, are included in the denominator of the diluted EPS calculation.

We may be required to calculate basic EPS using the two-class method as a result of our redeemable non-controlling interests. To the extent that the redemption value increases and exceeds the then-current fair value of a redeemable non-controlling interest, net income available to IPG common stockholders (used to calculate EPS) could be negatively impacted by that increase, subject to certain limitations. The partial or full recovery of any reductions to net income available to IPG common stockholders (used to calculate EPS) is limited to any cumulative prior-period reductions. For the years ended December 31, 2023, 2022 and 2021, there was no impact to EPS for adjustments related to our redeemable non-controlling interests.

We have pension and postretirement benefit plans covering certain domestic and international employees. We use various actuarial methods and assumptions in determining our net pension and postretirement benefit costs and obligations, including the discount rate used to determine the present value of future benefits, expected long-term rate of return on plan assets and healthcare cost trend rates. The overfunded or underfunded status of our pension and postretirement benefit plans is recorded on our Consolidated Balance Sheet.

Compensation costs related to share-based transactions, including employee stock options, are recognized in the Consolidated Financial Statements based on fair value. Stock-based compensation expense is generally recognized ratably over the requisite service period based on the estimated grant-date fair value, net of estimated forfeitures.

We account for repurchased common stock under the cost method and include such treasury stock as a component of our Consolidated Statements of Stockholders' Equity. Upon retirement, we reduce common stock for the par value of the shares being retired and the excess of the cost of the shares over par value as a reduction to APIC, to the extent there is APIC in the same class of stock, and any remaining amount to retained earnings. These retired shares remain authorized but unissued.

In October 2023, we retired 9.3 shares of our treasury stock, which resulted in a reduction in common stock of $0.9, treasury stock of $340.4 and APIC of $339.5. In October 2022, we retired 7.2 shares of our treasury stock, which resulted in a reduction in common stock of $0.7, treasury stock of $199.9 and APIC of $199.2. During 2021, there was no significant treasury stock activity due to the suspension of the share repurchase program.