<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>498</ContextCount>
  <ElementCount>510</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>146</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>12</UnitCount>
  <MyReports>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - CONSOLIDATED BALANCE SHEET</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedBalanceSheet</Role>
      <ShortName>CONSOLIDATED BALANCE SHEET</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001501 - Statement - CONSOLIDATED BALANCE SHEET (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedBalanceSheetParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEET (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1003000 - Statement - CONSOLIDATED STATEMENT OF OPERATIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfOperations</Role>
      <ShortName>CONSOLIDATED STATEMENT OF OPERATIONS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1004000 - Statement - CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfComprehensiveIncome</Role>
      <ShortName>CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1005000 - Statement - CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfShareholdersEquity</Role>
      <ShortName>CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1005501 - Statement - CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfShareholdersEquityParenthetical</Role>
      <ShortName>CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>1007000 - Statement - CONSOLIDATED STATEMENT OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlows</Role>
      <ShortName>CONSOLIDATED STATEMENT OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - BUSINESS AND BASIS OF PRESENTATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessAndBasisOfPresentation</Role>
      <ShortName>BUSINESS AND BASIS OF PRESENTATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - INVESTMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/Investments</Role>
      <ShortName>INVESTMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2103100 - Disclosure - EARNINGS PER SHARE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/EarningsPerShare</Role>
      <ShortName>EARNINGS PER SHARE</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - BUSINESS SEGMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessSegments</Role>
      <ShortName>BUSINESS SEGMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - ACCOUNTING FOR DERIVATIVES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivatives</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - REINSURANCE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/Reinsurance</Role>
      <ShortName>REINSURANCE</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2107100 - Disclosure - INCOME TAXES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxes</Role>
      <ShortName>INCOME TAXES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligations</Role>
      <ShortName>NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - INVESTMENT BORROWINGS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentBorrowings</Role>
      <ShortName>INVESTMENT BORROWINGS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - CHANGES IN COMMON STOCK</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ChangesInCommonStock</Role>
      <ShortName>CHANGES IN COMMON STOCK</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2111100 - Disclosure - SALES INDUCEMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/SalesInducements</Role>
      <ShortName>SALES INDUCEMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2112100 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/RecentlyIssuedAccountingStandards</Role>
      <ShortName>RECENTLY ISSUED ACCOUNTING STANDARDS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - LITIGATION AND OTHER LEGAL PROCEEDINGS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/LitigationAndOtherLegalProceedings</Role>
      <ShortName>LITIGATION AND OTHER LEGAL PROCEEDINGS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - CONSOLIDATED STATEMENT OF CASH FLOW</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlow</Role>
      <ShortName>CONSOLIDATED STATEMENT OF CASH FLOW</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2123100 - Disclosure - LEASES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/Leases</Role>
      <ShortName>LEASES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2125100 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntities</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2126100 - Disclosure - FAIR VALUE MEASUREMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurements</Role>
      <ShortName>FAIR VALUE MEASUREMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2201201 - Disclosure - BUSINESS AND BASIS OF PRESENTATION (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessAndBasisOfPresentationPolicies</Role>
      <ShortName>BUSINESS AND BASIS OF PRESENTATION (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2302301 - Disclosure - INVESTMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsTables</Role>
      <ShortName>INVESTMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/Investments</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2303301 - Disclosure - EARNINGS PER SHARE (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/EarningsPerShareTables</Role>
      <ShortName>EARNINGS PER SHARE (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/EarningsPerShare</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2304301 - Disclosure - BUSINESS SEGMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessSegmentsTables</Role>
      <ShortName>BUSINESS SEGMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/BusinessSegments</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - ACCOUNTING FOR DERIVATIVES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivativesTables</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/AccountingForDerivatives</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - INCOME TAXES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesTables</Role>
      <ShortName>INCOME TAXES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/IncomeTaxes</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2308301 - Disclosure - NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligationsTables</Role>
      <ShortName>NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligations</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2309301 - Disclosure - INVESTMENT BORROWINGS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentBorrowingsTables</Role>
      <ShortName>INVESTMENT BORROWINGS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/InvestmentBorrowings</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2312301 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/RecentlyIssuedAccountingStandardsTables</Role>
      <ShortName>RECENTLY ISSUED ACCOUNTING STANDARDS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/RecentlyIssuedAccountingStandards</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2315301 - Disclosure - CONSOLIDATED STATEMENT OF CASH FLOW (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlowTables</Role>
      <ShortName>CONSOLIDATED STATEMENT OF CASH FLOW (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlow</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2323301 - Disclosure - LEASES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/LeasesTables</Role>
      <ShortName>LEASES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/Leases</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2325301 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntitiesTables</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntities</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2326301 - Disclosure - FAIR VALUE MEASUREMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsTables</Role>
      <ShortName>FAIR VALUE MEASUREMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/FairValueMeasurements</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2401402 - Disclosure - BUSINESS AND BASIS OF PRESENTATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessAndBasisOfPresentationDetails</Role>
      <ShortName>BUSINESS AND BASIS OF PRESENTATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/BusinessAndBasisOfPresentationPolicies</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - INVESTMENTS - SCHEDULE OF UNREALIZED APPRECIATION (DEPRECIATION) ON INVESTMENTS INCLUDED IN ACCUMULATED OTHER COMPREHENSIVE INCOME (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsScheduleOfUnrealizedAppreciationDepreciationOnInvestmentsIncludedInAccumulatedOtherComprehensiveIncomeDetails</Role>
      <ShortName>INVESTMENTS - SCHEDULE OF UNREALIZED APPRECIATION (DEPRECIATION) ON INVESTMENTS INCLUDED IN ACCUMULATED OTHER COMPREHENSIVE INCOME (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2402403 - Disclosure - INVESTMENTS - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsNarrativeDetails</Role>
      <ShortName>INVESTMENTS - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2402404 - Disclosure - INVESTMENTS - SCHEDULE OF AMORTIZED COST, GROSS UNREALIZED GAINS AND LOSSES, ESTIMATED FAIR VALUE, AND ALLOWANCE FOR CREDIT LOSSES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsScheduleOfAmortizedCostGrossUnrealizedGainsAndLossesEstimatedFairValueAndAllowanceForCreditLossesDetails</Role>
      <ShortName>INVESTMENTS - SCHEDULE OF AMORTIZED COST, GROSS UNREALIZED GAINS AND LOSSES, ESTIMATED FAIR VALUE, AND ALLOWANCE FOR CREDIT LOSSES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2402405 - Disclosure - INVESTMENTS - SUMMARY OF INVESTMENTS BY CONTRACTUAL MATURITY (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfInvestmentsByContractualMaturityDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF INVESTMENTS BY CONTRACTUAL MATURITY (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2402406 - Disclosure - INVESTMENTS - SUMMARY OF INVESTMENTS WITH UNREALIZED LOSSES BY INVESTMENT CATEGORY (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfInvestmentsWithUnrealizedLossesByInvestmentCategoryDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF INVESTMENTS WITH UNREALIZED LOSSES BY INVESTMENT CATEGORY (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2402407 - Disclosure - INVESTMENTS - SUMMARY OF CHANGES IN THE ALLOWANCE FOR CURRENT EXPECTED CREDIT LOSSES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfChangesInAllowanceForCurrentExpectedCreditLossesDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF CHANGES IN THE ALLOWANCE FOR CURRENT EXPECTED CREDIT LOSSES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2402408 - Disclosure - INVESTMENTS - SUMMARY OF CARRYING VALUE AND ESTIMATED FAIR VALUE OF OUTSTANDING COMMERCIAL MORTGAGE LOANS AND UNDERLYING COLLATERAL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfCarryingValueAndEstimatedFairValueOfOutstandingCommercialMortgageLoansAndUnderlyingCollateralDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF CARRYING VALUE AND ESTIMATED FAIR VALUE OF OUTSTANDING COMMERCIAL MORTGAGE LOANS AND UNDERLYING COLLATERAL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2402409 - Disclosure - INVESTMENTS - SUMMARY OF CHANGES IN THE ALLOWANCE FOR CURRENT EXPECTED CREDIT LOSSES RELATED TO MORTGAGE LOANS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfChangesInAllowanceForCurrentExpectedCreditLossesRelatedToMortgageLoansDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF CHANGES IN THE ALLOWANCE FOR CURRENT EXPECTED CREDIT LOSSES RELATED TO MORTGAGE LOANS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2402410 - Disclosure - INVESTMENTS - NET REALIZED INVESTMENT GAINS (LOSSES) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsNetRealizedInvestmentGainsLossesDetails</Role>
      <ShortName>INVESTMENTS - NET REALIZED INVESTMENT GAINS (LOSSES) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2402411 - Disclosure - INVESTMENTS - SUMMARY OF CREDIT LOSSES RECOGNIZED IN EARNINGS ON FIXED MATURITY SECURITIES, AVAILABLE FOR SALE, FOR WHICH A PORTION OF THE OTHER-THAN-TEMPORARY IMPAIRMENT WAS ALSO RECOGNIZED IN OTHER COMPREHENSIVE INCOME (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsSummaryOfCreditLossesRecognizedInEarningsOnFixedMaturitySecuritiesAvailableForSaleForWhichPortionOfOtherThanTemporaryImpairmentWasAlsoRecognizedInOtherComprehensiveIncomeDetails</Role>
      <ShortName>INVESTMENTS - SUMMARY OF CREDIT LOSSES RECOGNIZED IN EARNINGS ON FIXED MATURITY SECURITIES, AVAILABLE FOR SALE, FOR WHICH A PORTION OF THE OTHER-THAN-TEMPORARY IMPAIRMENT WAS ALSO RECOGNIZED IN OTHER COMPREHENSIVE INCOME (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2403402 - Disclosure - EARNINGS PER SHARE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/EarningsPerShareDetails</Role>
      <ShortName>EARNINGS PER SHARE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/EarningsPerShareTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2404402 - Disclosure - BUSINESS SEGMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/BusinessSegmentsDetails</Role>
      <ShortName>BUSINESS SEGMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/BusinessSegmentsTables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - ACCOUNTING FOR DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivativesFairValueByBalanceSheetLocationDetails</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES - FAIR VALUE BY BALANCE SHEET LOCATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2405403 - Disclosure - ACCOUNTING FOR DERIVATIVES - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivativesNarrativeDetails</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2405404 - Disclosure - ACCOUNTING FOR DERIVATIVES - SCHEDULE PRE-TAX GAINS (LOSSES) RECOGNIZED IN NET INCOME FOR DERIVATIVE INSTRUMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivativesSchedulePreTaxGainsLossesRecognizedInNetIncomeForDerivativeInstrumentsDetails</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES - SCHEDULE PRE-TAX GAINS (LOSSES) RECOGNIZED IN NET INCOME FOR DERIVATIVE INSTRUMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2405405 - Disclosure - ACCOUNTING FOR DERIVATIVES - DERIVATIVES WITH MASTER NETTING ARRANGEMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/AccountingForDerivativesDerivativesWithMasterNettingArrangementsDetails</Role>
      <ShortName>ACCOUNTING FOR DERIVATIVES - DERIVATIVES WITH MASTER NETTING ARRANGEMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2406401 - Disclosure - REINSURANCE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ReinsuranceDetails</Role>
      <ShortName>REINSURANCE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/Reinsurance</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - INCOME TAXES - COMPONENTS OF TAX EXPENSE (BENEFIT) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesComponentsOfTaxExpenseBenefitDetails</Role>
      <ShortName>INCOME TAXES - COMPONENTS OF TAX EXPENSE (BENEFIT) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2407403 - Disclosure - INCOME TAXES - RECONCILIATION OF CORPORATE TAX RATE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesReconciliationOfCorporateTaxRateDetails</Role>
      <ShortName>INCOME TAXES - RECONCILIATION OF CORPORATE TAX RATE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2407404 - Disclosure - INCOME TAXES - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesNarrativeDetails</Role>
      <ShortName>INCOME TAXES - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2407405 - Disclosure - INCOME TAXES - DEFERRED ASSETS AND LIABILITIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesDeferredAssetsAndLiabilitiesDetails</Role>
      <ShortName>INCOME TAXES - DEFERRED ASSETS AND LIABILITIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2407406 - Disclosure - INCOME TAXES - NET OPERATING LOSSES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/IncomeTaxesNetOperatingLossesDetails</Role>
      <ShortName>INCOME TAXES - NET OPERATING LOSSES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2408402 - Disclosure - NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - SCHEDULE OF LONG-TERM DEBT INSTRUMENTS (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligationsScheduleOfLongTermDebtInstrumentsDetails</Role>
      <ShortName>NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - SCHEDULE OF LONG-TERM DEBT INSTRUMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - NARRATIVE (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligationsNarrativeDetails</Role>
      <ShortName>NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2408404 - Disclosure - NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - SCHEDULED REPAYMENT (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.cnoinc.com/role/NotesPayableDirectCorporateObligationsScheduledRepaymentDetails</Role>
      <ShortName>NOTES PAYABLE - DIRECT CORPORATE OBLIGATIONS - SCHEDULED REPAYMENT (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2409402 - Disclosure - INVESTMENT BORROWINGS - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentBorrowingsNarrativeDetails</Role>
      <ShortName>INVESTMENT BORROWINGS - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2409403 - Disclosure - INVESTMENT BORROWINGS - TERMS OF THE BORROWINGS FROM THE FHLB (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentBorrowingsTermsOfBorrowingsFromFhlbDetails</Role>
      <ShortName>INVESTMENT BORROWINGS - TERMS OF THE BORROWINGS FROM THE FHLB (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2410401 - Disclosure - CHANGES IN COMMON STOCK (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ChangesInCommonStockDetails</Role>
      <ShortName>CHANGES IN COMMON STOCK (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/ChangesInCommonStock</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2411401 - Disclosure - SALES INDUCEMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/SalesInducementsDetails</Role>
      <ShortName>SALES INDUCEMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/SalesInducements</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2412402 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/RecentlyIssuedAccountingStandardsNarrativeDetails</Role>
      <ShortName>RECENTLY ISSUED ACCOUNTING STANDARDS - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2412403 - Disclosure - RECENTLY ISSUED ACCOUNTING STANDARDS - IMPACT OF ADOPTION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/RecentlyIssuedAccountingStandardsImpactOfAdoptionDetails</Role>
      <ShortName>RECENTLY ISSUED ACCOUNTING STANDARDS - IMPACT OF ADOPTION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2413401 - Disclosure - LITIGATION AND OTHER LEGAL PROCEEDINGS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/LitigationAndOtherLegalProceedingsDetails</Role>
      <ShortName>LITIGATION AND OTHER LEGAL PROCEEDINGS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/LitigationAndOtherLegalProceedings</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2415402 - Disclosure - CONSOLIDATED STATEMENT OF CASH FLOW (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlowDetails</Role>
      <ShortName>CONSOLIDATED STATEMENT OF CASH FLOW (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/ConsolidatedStatementOfCashFlowTables</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2423402 - Disclosure - LEASES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/LeasesDetails</Role>
      <ShortName>LEASES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.cnoinc.com/role/LeasesTables</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2425402 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES - BALANCE SHEET ITEMS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntitiesBalanceSheetItemsDetails</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES - BALANCE SHEET ITEMS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2425403 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntitiesNarrativeDetails</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2425404 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES - CHANGES IN ALLOWANCE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntitiesChangesInAllowanceDetails</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES - CHANGES IN ALLOWANCE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2425405 - Disclosure - INVESTMENTS IN VARIABLE INTEREST ENTITIES - SCHEDULE OF VIEs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/InvestmentsInVariableInterestEntitiesScheduleOfViesDetails</Role>
      <ShortName>INVESTMENTS IN VARIABLE INTEREST ENTITIES - SCHEDULE OF VIEs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2426402 - Disclosure - FAIR VALUE MEASUREMENTS - NARRATIVE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsNarrativeDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - NARRATIVE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2426403 - Disclosure - FAIR VALUE MEASUREMENTS - MEASUREMENTS BY INPUT LEVEL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsMeasurementsByInputLevelDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - MEASUREMENTS BY INPUT LEVEL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2426404 - Disclosure - FAIR VALUE MEASUREMENTS - RECURRING BASIS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsRecurringBasisDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - RECURRING BASIS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2426405 - Disclosure - FAIR VALUE MEASUREMENTS - BALANCE SHEET RECURRING (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsBalanceSheetRecurringDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - BALANCE SHEET RECURRING (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2426406 - Disclosure - FAIR VALUE MEASUREMENTS - FAIR VALUE ACTIVITY (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsFairValueActivityDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - FAIR VALUE ACTIVITY (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="cno0630202010-q.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2426407 - Disclosure - FAIR VALUE MEASUREMENTS - FAIR VALUE INPUTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.cnoinc.com/role/FairValueMeasurementsFairValueInputsDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - FAIR VALUE INPUTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</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-Q" original="cno0630202010-q.htm">cno0630202010-q.htm</File>
    <File>cno-20200630.xsd</File>
    <File>cno-20200630_cal.xml</File>
    <File>cno-20200630_def.xml</File>
    <File>cno-20200630_lab.xml</File>
    <File>cno-20200630_pre.xml</File>
    <File>cno06302020ex311.htm</File>
    <File>cno06302020ex312.htm</File>
    <File>cno06302020ex321.htm</File>
    <File>cno06302020ex322.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>orgchart2020.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/srt/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/us-gaap/2020-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2019-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
