<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.19.3.a.u2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>349</ContextCount>
  <ElementCount>675</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>80</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>6</UnitCount>
  <MyReports>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document and Entity Information Document</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DocumentAndEntityInformationDocument</Role>
      <ShortName>Document and Entity Information Document</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedStatementsOfOperations</Role>
      <ShortName>Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1002000 - Statement - Consolidated Statements of Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>Consolidated Statements of Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1003000 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1003501 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1004000 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1005000 - Statement - Consolidated Statements of Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ConsolidatedStatementsOfStockholdersEquity</Role>
      <ShortName>Consolidated Statements of Stockholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Significant Accounting Policies (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</Role>
      <ShortName>Significant Accounting Policies (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - Revenue (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/RevenueNotes</Role>
      <ShortName>Revenue (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Debt and Credit Agreements (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsNotes</Role>
      <ShortName>Debt and Credit Agreements (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - Earnings Per Share (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/EarningsPerShareNotes</Role>
      <ShortName>Earnings Per Share (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - Acquisitions (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsNotes</Role>
      <ShortName>Acquisitions (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - Supplementary Data (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataNotes</Role>
      <ShortName>Supplementary Data (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2114100 - Disclosure - Goodwill and Other Intangible Assets (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/GoodwillAndOtherIntangibleAssetsNotes</Role>
      <ShortName>Goodwill and Other Intangible Assets (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - Income Taxes (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesNotes</Role>
      <ShortName>Income Taxes (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Accumulated Other Comprehensive Loss, Net of Tax (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/AccumulatedOtherComprehensiveLossNetOfTaxNotes</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Net of Tax (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2117100 - Disclosure - Incentive Compensation Plans (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansNotes</Role>
      <ShortName>Incentive Compensation Plans (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2118100 - Disclosure - Fair Value Measurements (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/FairValueMeasurementsNotes</Role>
      <ShortName>Fair Value Measurements (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2119100 - Disclosure - Employee Benefits (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsNotes</Role>
      <ShortName>Employee Benefits (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2120100 - Disclosure - Segment Information (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/SegmentInformationNotes</Role>
      <ShortName>Segment Information (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2122100 - Disclosure - Commitments and Contingencies (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/CommitmentsAndContingenciesNotes</Role>
      <ShortName>Commitments and Contingencies (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2123100 - Disclosure - Recent Accounting Standards (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/RecentAccountingStandardsNotes</Role>
      <ShortName>Recent Accounting Standards (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2124100 - Disclosure - Results by Quarter (Unaudited) (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/ResultsByQuarterUnauditedNotes</Role>
      <ShortName>Results by Quarter (Unaudited) (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2125100 - Disclosure - Subsequent Events (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/SubsequentEventsNotes</Role>
      <ShortName>Subsequent Events (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2126100 - Disclosure - Restructuring Charges (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/RestructuringChargesNotes</Role>
      <ShortName>Restructuring Charges (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2127100 - Disclosure - Leases (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.interpublic.com/role/LeasesNotes</Role>
      <ShortName>Leases (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2201201 - Disclosure - Significant Accounting Policies Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesBasisOfPresentationPolicies</Role>
      <ShortName>Significant Accounting Policies Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2201202 - Disclosure - Significant Accounting Policies Leases (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesLeasesPolicies</Role>
      <ShortName>Significant Accounting Policies Leases (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2201204 - Disclosure - Significant Accounting Policies Principles of Consolidation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesPrinciplesOfConsolidationPolicies</Role>
      <ShortName>Significant Accounting Policies Principles of Consolidation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2201205 - Disclosure - Significant Accounting Policies Reclassifications (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesReclassificationsPolicies</Role>
      <ShortName>Significant Accounting Policies Reclassifications (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2201206 - Disclosure - Significant Accounting Policies Use of Estimates (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesUseOfEstimatesPolicies</Role>
      <ShortName>Significant Accounting Policies Use of Estimates (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2201207 - Disclosure - Significant Accounting Policies Revenue Recognition (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesRevenueRecognitionPolicies</Role>
      <ShortName>Significant Accounting Policies Revenue Recognition (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2201208 - Disclosure - Significant Accounting Policies Cash and Cash Equivalents (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesCashAndCashEquivalentsPolicies</Role>
      <ShortName>Significant Accounting Policies Cash and Cash Equivalents (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2201209 - Disclosure - Significant Accounting Policies Allowance for Doubtful Accounts (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesAllowanceForDoubtfulAccountsPolicies</Role>
      <ShortName>Significant Accounting Policies Allowance for Doubtful Accounts (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2201210 - Disclosure - Significant Accounting Policies Acounts Receivable, Billable to Clients (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesAcountsReceivableBillableToClientsPolicies</Role>
      <ShortName>Significant Accounting Policies Acounts Receivable, Billable to Clients (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2201211 - Disclosure - Significant Accounting Policies Accounts Payable (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesAccountsPayablePolicies</Role>
      <ShortName>Significant Accounting Policies Accounts Payable (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2201212 - Disclosure - Significant Accounting Policies Investments (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesInvestmentsPolicies</Role>
      <ShortName>Significant Accounting Policies Investments (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2201213 - Disclosure - Significant Accounting Policies Derivatives (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesDerivativesPolicies</Role>
      <ShortName>Significant Accounting Policies Derivatives (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2201214 - Disclosure - Significant Accounting Policies Property and Equipment (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesPropertyAndEquipmentPolicies</Role>
      <ShortName>Significant Accounting Policies Property and Equipment (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2201215 - Disclosure - Significant Accounting Policies Goodwill and Other Intangible Assets (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesGoodwillAndOtherIntangibleAssetsPolicies</Role>
      <ShortName>Significant Accounting Policies Goodwill and Other Intangible Assets (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2201216 - Disclosure - Significant Accounting Policies Foreign Currencies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesForeignCurrenciesPolicies</Role>
      <ShortName>Significant Accounting Policies Foreign Currencies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2201217 - Disclosure - Significant Accounting Policies Income Taxes (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesIncomeTaxesPolicies</Role>
      <ShortName>Significant Accounting Policies Income Taxes (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2201218 - Disclosure - Significant Accounting Policies Redeemable Noncontrolling Interests (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesRedeemableNoncontrollingInterestsPolicies</Role>
      <ShortName>Significant Accounting Policies Redeemable Noncontrolling Interests (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2201219 - Disclosure - Significant Accounting Policies Earnings Per Share (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesEarningsPerSharePolicies</Role>
      <ShortName>Significant Accounting Policies Earnings Per Share (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2201220 - Disclosure - Significant Accounting Policies Pension and Postretirement Benefits (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesPensionAndPostretirementBenefitsPolicies</Role>
      <ShortName>Significant Accounting Policies Pension and Postretirement Benefits (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2201221 - Disclosure - Significant Accounting Policies Stock-Based Compensation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesStockBasedCompensationPolicies</Role>
      <ShortName>Significant Accounting Policies Stock-Based Compensation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2201222 - Disclosure - Significant Accounting Policies Treasury Stock (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SignificantAccountingPoliciesTreasuryStockPolicies</Role>
      <ShortName>Significant Accounting Policies Treasury Stock (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SignificantAccountingPoliciesNotes</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2304301 - Disclosure - Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueTables</Role>
      <ShortName>Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/RevenueNotes</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Debt and Credit Agreements Schedule of Long-term Debt Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsScheduleOfLongTermDebtInstrumentsTables</Role>
      <ShortName>Debt and Credit Agreements Schedule of Long-term Debt Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2306302 - Disclosure - Debt and Credit Agreements Schedule of Maturities of Long-term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsScheduleOfMaturitiesOfLongTermDebtTables</Role>
      <ShortName>Debt and Credit Agreements Schedule of Maturities of Long-term Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2306304 - Disclosure - Debt and Credit Agreements Schedule of Financial Covenants in Credit Agreement (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsScheduleOfFinancialCovenantsInCreditAgreementTables</Role>
      <ShortName>Debt and Credit Agreements Schedule of Financial Covenants in Credit Agreement (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2308301 - Disclosure - Earnings Per Share Basic and Diluted Earnings Per Common Share Available to IPG Common Stockholders (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EarningsPerShareBasicAndDilutedEarningsPerCommonShareAvailableToIpgCommonStockholdersTables</Role>
      <ShortName>Earnings Per Share Basic and Diluted Earnings Per Common Share Available to IPG Common Stockholders (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2309301 - Disclosure - Acquisitions Cash Paid for Current and Prior Years' Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsCashPaidForCurrentAndPriorYearsAcquisitionsTables</Role>
      <ShortName>Acquisitions Cash Paid for Current and Prior Years' Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2309302 - Disclosure - Acquisitions Redeemable Noncontrolling Interest (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsRedeemableNoncontrollingInterestTables</Role>
      <ShortName>Acquisitions Redeemable Noncontrolling Interest (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2313301 - Disclosure - Supplementary Data Valuation and Qualifying Accounts - Allowance for Uncollectible Accounts (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataValuationAndQualifyingAccountsAllowanceForUncollectibleAccountsTables</Role>
      <ShortName>Supplementary Data Valuation and Qualifying Accounts - Allowance for Uncollectible Accounts (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2313302 - Disclosure - Supplementary Data Property and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataPropertyAndEquipmentTables</Role>
      <ShortName>Supplementary Data Property and Equipment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2313303 - Disclosure - Supplementary Data Accrued Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataAccruedLiabilitiesTables</Role>
      <ShortName>Supplementary Data Accrued Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2313304 - Disclosure - Supplementary Data Other Expense, Net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataOtherExpenseNetTables</Role>
      <ShortName>Supplementary Data Other Expense, Net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2313305 - Disclosure - Supplementary Data Share Repurchase Program (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataShareRepurchaseProgramTables</Role>
      <ShortName>Supplementary Data Share Repurchase Program (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2313306 - Disclosure - Supplementary Data Supplemental Cash Flow Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataSupplementalCashFlowInformationTables</Role>
      <ShortName>Supplementary Data Supplemental Cash Flow Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2314301 - Disclosure - Goodwill and Other Intangible Assets Changes in Carrying Value of Goodwill (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/GoodwillAndOtherIntangibleAssetsChangesInCarryingValueOfGoodwillTables</Role>
      <ShortName>Goodwill and Other Intangible Assets Changes in Carrying Value of Goodwill (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2314302 - Disclosure - Goodwill and Other Intangible Assets Summary of Other Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/GoodwillAndOtherIntangibleAssetsSummaryOfOtherIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Other Intangible Assets Summary of Other Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2314303 - Disclosure - Goodwill and Other Intangible Assets Estimated future amortization of other intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/GoodwillAndOtherIntangibleAssetsEstimatedFutureAmortizationOfOtherIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Other Intangible Assets Estimated future amortization of other intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2315301 - Disclosure - Income Taxes Schedule of Income before Income Tax, Domestic and Foreign (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTables</Role>
      <ShortName>Income Taxes Schedule of Income before Income Tax, Domestic and Foreign (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2315302 - Disclosure - Income Taxes Schedule of Components of Provision for Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesScheduleOfComponentsOfProvisionForIncomeTaxesTables</Role>
      <ShortName>Income Taxes Schedule of Components of Provision for Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2315303 - Disclosure - Income Taxes Schedule of Effective Income Tax Rate Reconciliation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesScheduleOfEffectiveIncomeTaxRateReconciliationTables</Role>
      <ShortName>Income Taxes Schedule of Effective Income Tax Rate Reconciliation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2315304 - Disclosure - Income Taxes Schedule of Deferred Tax Assets and Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesTables</Role>
      <ShortName>Income Taxes Schedule of Deferred Tax Assets and Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2315305 - Disclosure - Income Taxes Summary of Valuation Allowance (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesSummaryOfValuationAllowanceTables</Role>
      <ShortName>Income Taxes Summary of Valuation Allowance (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2315306 - Disclosure - Income Taxes Schedule of Unrecognized Tax Benefits Activity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesScheduleOfUnrecognizedTaxBenefitsActivityTables</Role>
      <ShortName>Income Taxes Schedule of Unrecognized Tax Benefits Activity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2316301 - Disclosure - Accumulated Other Comprehensive Loss, Net of Tax Schedule of Accumulated Other Comprehensive Income (Loss) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AccumulatedOtherComprehensiveLossNetOfTaxScheduleOfAccumulatedOtherComprehensiveIncomeLossTables</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Net of Tax Schedule of Accumulated Other Comprehensive Income (Loss) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2316302 - Disclosure - Accumulated Other Comprehensive Loss, Net of Tax Reclassification out of Accumulated Other Comprehensive Income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AccumulatedOtherComprehensiveLossNetOfTaxReclassificationOutOfAccumulatedOtherComprehensiveIncomeTables</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Net of Tax Reclassification out of Accumulated Other Comprehensive Income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2317301 - Disclosure - Incentive Compensation Plans Schedule of Stock-based Compensation Expense (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansScheduleOfStockBasedCompensationExpenseTables</Role>
      <ShortName>Incentive Compensation Plans Schedule of Stock-based Compensation Expense (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2317302 - Disclosure - Incentive Compensation Plans Schedule of Stock Options Activity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansScheduleOfStockOptionsActivityTables</Role>
      <ShortName>Incentive Compensation Plans Schedule of Stock Options Activity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2317303 - Disclosure - Incentive Compensation Plans Stock-based Compensation, Grants in Period Weighted Average (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansStockBasedCompensationGrantsInPeriodWeightedAverageTables</Role>
      <ShortName>Incentive Compensation Plans Stock-based Compensation, Grants in Period Weighted Average (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2317304 - Disclosure - Incentive Compensation Plans Schedule of Nonvested Stock Activity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansScheduleOfNonvestedStockActivityTables</Role>
      <ShortName>Incentive Compensation Plans Schedule of Nonvested Stock Activity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2318301 - Disclosure - Fair Value Measurements Fair Value of Assets and Liabilities Measured on a Recurring Basis (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/FairValueMeasurementsFairValueOfAssetsAndLiabilitiesMeasuredOnRecurringBasisTables</Role>
      <ShortName>Fair Value Measurements Fair Value of Assets and Liabilities Measured on a Recurring Basis (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2318302 - Disclosure - Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Nonrecurring (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/FairValueMeasurementsAssetsAndLiabilitiesMeasuredAtFairValueOnNonrecurringTables</Role>
      <ShortName>Fair Value Measurements Assets and Liabilities Measured at Fair Value on a Nonrecurring (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2319301 - Disclosure - Schedule of Defined Benefit Plans Disclosures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ScheduleOfDefinedBenefitPlansDisclosuresTables</Role>
      <ShortName>Schedule of Defined Benefit Plans Disclosures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2319302 - Disclosure - Employee Benefits Schedule of Net Benefit Costs (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsScheduleOfNetBenefitCostsTables</Role>
      <ShortName>Employee Benefits Schedule of Net Benefit Costs (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2319303 - Disclosure - Employee Benefits Fair Value of Pension Plan Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsFairValueOfPensionPlanAssetsTables</Role>
      <ShortName>Employee Benefits Fair Value of Pension Plan Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2319304 - Disclosure - Employee Benefits Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsScheduleOfEffectOfSignificantUnobservableInputsChangesInPlanAssetsTables</Role>
      <ShortName>Employee Benefits Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2319305 - Disclosure - Employee Benefits Schedule of Allocation of Plan Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsScheduleOfAllocationOfPlanAssetsTables</Role>
      <ShortName>Employee Benefits Schedule of Allocation of Plan Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2319306 - Disclosure - Employee Benefits Schedule of Estimated Future Benefit Payments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsScheduleOfEstimatedFutureBenefitPaymentsTables</Role>
      <ShortName>Employee Benefits Schedule of Estimated Future Benefit Payments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>2320301 - Disclosure - Segment Information Schedule of Segment Reporting Information, by Segment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SegmentInformationScheduleOfSegmentReportingInformationBySegmentTables</Role>
      <ShortName>Segment Information Schedule of Segment Reporting Information, by Segment (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>2320302 - Disclosure - Segment Information Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SegmentInformationScheduleOfRevenueFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTables</Role>
      <ShortName>Segment Information Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>2322301 - Disclosure - Commitments and Contingencies Schedule of Contingent Acquisition Obligations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/CommitmentsAndContingenciesScheduleOfContingentAcquisitionObligationsTables</Role>
      <ShortName>Commitments and Contingencies Schedule of Contingent Acquisition Obligations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>2324301 - Disclosure - Results by Quarter (Unaudited) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ResultsByQuarterUnauditedTables</Role>
      <ShortName>Results by Quarter (Unaudited) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/ResultsByQuarterUnauditedNotes</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>2326301 - Disclosure - Restructuring Charges (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RestructuringChargesTables</Role>
      <ShortName>Restructuring Charges (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/RestructuringChargesNotes</ParentRole>
      <Position>88</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>2327301 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/LeasesNotes</ParentRole>
      <Position>89</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>2401403 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SummaryOfSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>2404402 - Disclosure - Revenue Income Statement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueIncomeStatementDetails</Role>
      <ShortName>Revenue Income Statement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>2404403 - Disclosure - Revenue Balance Sheet (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueBalanceSheetDetails</Role>
      <ShortName>Revenue Balance Sheet (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>2404404 - Disclosure - Revenue Statement of Cash Flows (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueStatementOfCashFlowsDetails</Role>
      <ShortName>Revenue Statement of Cash Flows (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>2404405 - Disclosure - Revenue Major Geographical Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueMajorGeographicalAreaDetails</Role>
      <ShortName>Revenue Major Geographical Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>2404406 - Disclosure - Revenue Contract Balances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RevenueContractBalancesDetails</Role>
      <ShortName>Revenue Contract Balances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>2406405 - Disclosure - Debt and Credit Agreements Long-Term Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsLongTermDebtDetails</Role>
      <ShortName>Debt and Credit Agreements Long-Term Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>2406406 - Disclosure - Debt and Credit Agreements Debt Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsDebtTransactionsDetails</Role>
      <ShortName>Debt and Credit Agreements Debt Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>2406407 - Disclosure - Debt and Credit Agreements Annual Maturities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsAnnualMaturitiesDetails</Role>
      <ShortName>Debt and Credit Agreements Annual Maturities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>2406408 - Disclosure - Debt and Credit Agreements Credit Agreements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsCreditAgreementsDetails</Role>
      <ShortName>Debt and Credit Agreements Credit Agreements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>2406409 - Disclosure - Debt and Credit Agreements Commercial Paper (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsCommercialPaperDetails</Role>
      <ShortName>Debt and Credit Agreements Commercial Paper (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>2406410 - Disclosure - Debt and Credit Agreements Cash Pooling (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/DebtAndCreditAgreementsCashPoolingDetails</Role>
      <ShortName>Debt and Credit Agreements Cash Pooling (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>2408402 - Disclosure - Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EarningsPerShareDetails</Role>
      <ShortName>Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/EarningsPerShareBasicAndDilutedEarningsPerCommonShareAvailableToIpgCommonStockholdersTables</ParentRole>
      <Position>102</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>2409403 - Disclosure - Acquisitions Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsNarrativeDetails</Role>
      <ShortName>Acquisitions Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>2409404 - Disclosure - Acquisitions Cash Paid for Acquisitions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsCashPaidForAcquisitionsDetails</Role>
      <ShortName>Acquisitions Cash Paid for Acquisitions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>2409405 - Disclosure - Redeemable Noncontrolling Interests (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RedeemableNoncontrollingInterestsDetails</Role>
      <ShortName>Redeemable Noncontrolling Interests (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>2409406 - Disclosure - Acquisitions Acxiom Acquisition (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AcquisitionsAcxiomAcquisitionDetails</Role>
      <ShortName>Acquisitions Acxiom Acquisition (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>2413407 - Disclosure - Valuation and Qualifying Accounts - Allowance for Uncollectible Accounts Receivable (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ValuationAndQualifyingAccountsAllowanceForUncollectibleAccountsReceivableDetails</Role>
      <ShortName>Valuation and Qualifying Accounts - Allowance for Uncollectible Accounts Receivable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>2413408 - Disclosure - Supplementary Data Property and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementaryDataPropertyAndEquipmentDetails</Role>
      <ShortName>Supplementary Data Property and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SupplementaryDataPropertyAndEquipmentTables</ParentRole>
      <Position>108</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>2413409 - Disclosure - Accrued Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AccruedLiabilitiesDetails</Role>
      <ShortName>Accrued Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>2413410 - Disclosure - Other Expense, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/OtherExpenseNetDetails</Role>
      <ShortName>Other Expense, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>2413411 - Disclosure - Share Repurchase Program (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ShareRepurchaseProgramDetails</Role>
      <ShortName>Share Repurchase Program (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>2413412 - Disclosure - Supplemental Cash Flow Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SupplementalCashFlowInformationDetails</Role>
      <ShortName>Supplemental Cash Flow Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>2414404 - Disclosure - Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/GoodwillDetails</Role>
      <ShortName>Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/GoodwillAndOtherIntangibleAssetsChangesInCarryingValueOfGoodwillTables</ParentRole>
      <Position>113</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>2414405 - Disclosure - Other Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/OtherIntangibleAssetsDetails</Role>
      <ShortName>Other Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>2415407 - Disclosure - Components of Income Before Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ComponentsOfIncomeBeforeIncomeTaxesDetails</Role>
      <ShortName>Components of Income Before Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>2415408 - Disclosure - Provision for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ProvisionForIncomeTaxesDetails</Role>
      <ShortName>Provision for Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>2415409 - Disclosure - Reconciliation of Effective Income Tax Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ReconciliationOfEffectiveIncomeTaxRateDetails</Role>
      <ShortName>Reconciliation of Effective Income Tax Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>2415410 - Disclosure - Income Taxes Primary Impact on Provision for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesPrimaryImpactOnProvisionForIncomeTaxesDetails</Role>
      <ShortName>Income Taxes Primary Impact on Provision for Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>118</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>2415411 - Disclosure - Components of Deferred Tax Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ComponentsOfDeferredTaxAssetsDetails</Role>
      <ShortName>Components of Deferred Tax Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>119</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>2415412 - Disclosure - Income Taxes Change in Valuation Allowances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncomeTaxesChangeInValuationAllowancesDetails</Role>
      <ShortName>Income Taxes Change in Valuation Allowances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>120</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>2415413 - Disclosure - Unrecognized Tax Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/UnrecognizedTaxBenefitsDetails</Role>
      <ShortName>Unrecognized Tax Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>121</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>2416403 - Disclosure - Accumulated Other Comprehensive Loss, Net of Tax Changes in AOCI (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AccumulatedOtherComprehensiveLossNetOfTaxChangesInAociDetails</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Net of Tax Changes in AOCI (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>122</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>2416404 - Disclosure - Accumulated Other Comprehensive Loss, Net of Tax Reclassifications from AOCI, net of tax (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/AccumulatedOtherComprehensiveLossNetOfTaxReclassificationsFromAociNetOfTaxDetails</Role>
      <ShortName>Accumulated Other Comprehensive Loss, Net of Tax Reclassifications from AOCI, net of tax (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>123</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>2417405 - Disclosure - Plan Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/PlanInformationDetails</Role>
      <ShortName>Plan Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>124</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>2417406 - Disclosure - Stock Based Compensation Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/StockBasedCompensationExpenseDetails</Role>
      <ShortName>Stock Based Compensation Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>125</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>2417407 - Disclosure - Incentive Compensation Plans Stock Option Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansStockOptionActivityDetails</Role>
      <ShortName>Incentive Compensation Plans Stock Option Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>126</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>2417408 - Disclosure - Share-based Compensation Awards (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ShareBasedCompensationAwardsDetails</Role>
      <ShortName>Share-based Compensation Awards (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>127</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>2417409 - Disclosure - Non-vested Award Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/NonVestedAwardActivityDetails</Role>
      <ShortName>Non-vested Award Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>128</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R129.htm</HtmlFileName>
      <LongName>2417410 - Disclosure - Incentive Compensation Plans Employee Stock Purchase Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/IncentiveCompensationPlansEmployeeStockPurchasePlansDetails</Role>
      <ShortName>Incentive Compensation Plans Employee Stock Purchase Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>129</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R130.htm</HtmlFileName>
      <LongName>2418403 - Disclosure - Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/FairValueOnRecurringBasisDetails</Role>
      <ShortName>Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>130</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R131.htm</HtmlFileName>
      <LongName>2418404 - Disclosure - Fair Value on a Nonrecurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/FairValueOnNonrecurringBasisDetails</Role>
      <ShortName>Fair Value on a Nonrecurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>131</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>2419407 - Disclosure - Employee Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsDetails</Role>
      <ShortName>Employee Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/EmployeeBenefitsScheduleOfNetBenefitCostsTables</ParentRole>
      <Position>132</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>2419408 - Disclosure - Pension and Postretirement Benefit Obligation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/PensionAndPostretirementBenefitObligationDetails</Role>
      <ShortName>Pension and Postretirement Benefit Obligation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>133</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>2419409 - Disclosure - Net Periodic Cost (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/NetPeriodicCostDetails</Role>
      <ShortName>Net Periodic Cost (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>134</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R135.htm</HtmlFileName>
      <LongName>2419410 - Disclosure - Fair Value of Pension Plan Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/FairValueOfPensionPlanAssetsDetails</Role>
      <ShortName>Fair Value of Pension Plan Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>135</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R136.htm</HtmlFileName>
      <LongName>2419411 - Disclosure - Employee Benefits Allocation of Plan Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/EmployeeBenefitsAllocationOfPlanAssetsDetails</Role>
      <ShortName>Employee Benefits Allocation of Plan Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>136</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R137.htm</HtmlFileName>
      <LongName>2419412 - Disclosure - Pension Cash Flows (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/PensionCashFlowsDetails</Role>
      <ShortName>Pension Cash Flows (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>137</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R138.htm</HtmlFileName>
      <LongName>2419413 - Disclosure - Savings Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SavingsPlansDetails</Role>
      <ShortName>Savings Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>138</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>2420403 - Disclosure - Segment Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SegmentOperationsDetails</Role>
      <ShortName>Segment Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>139</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R140.htm</HtmlFileName>
      <LongName>2420404 - Disclosure - Segment Information Major Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SegmentInformationMajorGeographicAreaDetails</Role>
      <ShortName>Segment Information Major Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>140</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R141.htm</HtmlFileName>
      <LongName>2422402 - Disclosure - Guarantees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/GuaranteesDetails</Role>
      <ShortName>Guarantees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>141</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R142.htm</HtmlFileName>
      <LongName>2422403 - Disclosure - Contingent Acquisition Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ContingentAcquisitionObligationsDetails</Role>
      <ShortName>Contingent Acquisition Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>142</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R143.htm</HtmlFileName>
      <LongName>2424402 - Disclosure - Results by Quarter (Unaudited) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/ResultsByQuarterUnauditedDetails</Role>
      <ShortName>Results by Quarter (Unaudited) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/ResultsByQuarterUnauditedTables</ParentRole>
      <Position>143</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R144.htm</HtmlFileName>
      <LongName>2425402 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/SubsequentEventsNotes</ParentRole>
      <Position>144</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>2426402 - Disclosure - Restructuring Charges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/RestructuringChargesDetails</Role>
      <ShortName>Restructuring Charges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/RestructuringChargesTables</ParentRole>
      <Position>145</Position>
    </Report>
    <Report instance="ipg12311910k.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R146.htm</HtmlFileName>
      <LongName>2427402 - Disclosure - Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.interpublic.com/role/LeasesDetails</Role>
      <ShortName>Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.interpublic.com/role/LeasesTables</ParentRole>
      <Position>146</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-K" original="ipg12311910k.htm">ipg12311910k.htm</File>
    <File>a10iiia62.htm</File>
    <File>a10iiia63.htm</File>
    <File>a10iiia64.htm</File>
    <File>a10iiia65.htm</File>
    <File>a10iiia66.htm</File>
    <File>a10iiia67.htm</File>
    <File>a10iiia68.htm</File>
    <File>a10iiia69.htm</File>
    <File>a10iiia71.htm</File>
    <File>a4vi.htm</File>
    <File>ipg-20191231.xsd</File>
    <File>ipg-20191231_cal.xml</File>
    <File>ipg-20191231_def.xml</File>
    <File>ipg-20191231_lab.xml</File>
    <File>ipg-20191231_pre.xml</File>
    <File>ipg12311910kex21.htm</File>
    <File>ipg12311910kex23.htm</File>
    <File>ipg12311910kex24.htm</File>
    <File>ipg12311910kex311.htm</File>
    <File>ipg12311910kex312.htm</File>
    <File>ipg12311910kex32.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>ipglogo61617a18.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/country/2017-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/us-gaap/2019-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2019-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2019-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
