<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>621</ContextCount>
  <ElementCount>440</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>175</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>18</UnitCount>
  <MyReports>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - COVER PAGE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COVERPAGE</Role>
      <ShortName>COVER PAGE</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - CONDENSED CONSOLIDATED INCOME STATEMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDINCOMESTATEMENTS</Role>
      <ShortName>CONDENSED CONSOLIDATED INCOME STATEMENTS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVEINCOME</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETS</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDBALANCESHEETSParenthetical</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWS</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCASHFLOWSParenthetical</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFEQUITY</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFEQUITYParenthetical</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - GENERAL INFORMATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GENERALINFORMATION</Role>
      <ShortName>GENERAL INFORMATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - ACQUISITIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/ACQUISITIONS</Role>
      <ShortName>ACQUISITIONS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - DISPOSITION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DISPOSITION</Role>
      <ShortName>DISPOSITION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - OPERATING REVENUES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUES</Role>
      <ShortName>OPERATING REVENUES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - CREDIT LOSSES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CREDITLOSSES</Role>
      <ShortName>CREDIT LOSSES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - REGULATORY ASSETS AND LIABILITIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYASSETSANDLIABILITIES</Role>
      <ShortName>REGULATORY ASSETS AND LIABILITIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/PROPERTYPLANTANDEQUIPMENT</Role>
      <ShortName>PROPERTY, PLANT, AND EQUIPMENT</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - COMMON EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITY</Role>
      <ShortName>COMMON EQUITY</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - SHORT-TERM DEBT AND LINES OF CREDIT</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SHORTTERMDEBTANDLINESOFCREDIT</Role>
      <ShortName>SHORT-TERM DEBT AND LINES OF CREDIT</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - LONG-TERM DEBT</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/LONGTERMDEBT</Role>
      <ShortName>LONG-TERM DEBT</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - MATERIALS, SUPPLIES, AND INVENTORIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/MATERIALSSUPPLIESANDINVENTORIES</Role>
      <ShortName>MATERIALS, SUPPLIES, AND INVENTORIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - INCOME TAXES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INCOMETAXES</Role>
      <ShortName>INCOME TAXES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - FAIR VALUE MEASUREMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTS</Role>
      <ShortName>FAIR VALUE MEASUREMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - DERIVATIVE INSTRUMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTS</Role>
      <ShortName>DERIVATIVE INSTRUMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - GUARANTEES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GUARANTEES</Role>
      <ShortName>GUARANTEES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - EMPLOYEE BENEFITS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/EMPLOYEEBENEFITS</Role>
      <ShortName>EMPLOYEE BENEFITS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - GOODWILL AND INTANGIBLES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLES</Role>
      <ShortName>GOODWILL AND INTANGIBLES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATES</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - SEGMENT INFORMATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SEGMENTINFORMATION</Role>
      <ShortName>SEGMENT INFORMATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - VARIABLE INTEREST ENTITIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/VARIABLEINTERESTENTITIES</Role>
      <ShortName>VARIABLE INTEREST ENTITIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952179 - Disclosure - COMMITMENTS AND CONTINGENCIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMITMENTSANDCONTINGENCIES</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9952180 - Disclosure - SUPPLEMENTAL CASH FLOW INFORMATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SUPPLEMENTALCASHFLOWINFORMATION</Role>
      <ShortName>SUPPLEMENTAL CASH FLOW INFORMATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9952181 - Disclosure - REGULATORY ENVIRONMENT</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENT</Role>
      <ShortName>REGULATORY ENVIRONMENT</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9952182 - Disclosure - OTHER INCOME, NET</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OTHERINCOMENET</Role>
      <ShortName>OTHER INCOME, NET</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9952183 - Disclosure - NEW ACCOUNTING PRONOUNCEMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/NEWACCOUNTINGPRONOUNCEMENTS</Role>
      <ShortName>NEW ACCOUNTING PRONOUNCEMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - GENERAL INFORMATION (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GENERALINFORMATIONPolicies</Role>
      <ShortName>GENERAL INFORMATION (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - OPERATING REVENUES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESTables</Role>
      <ShortName>OPERATING REVENUES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/OPERATINGREVENUES</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - CREDIT LOSSES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CREDITLOSSESTables</Role>
      <ShortName>CREDIT LOSSES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/CREDITLOSSES</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - REGULATORY ASSETS AND LIABILITIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYASSETSANDLIABILITIESTables</Role>
      <ShortName>REGULATORY ASSETS AND LIABILITIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/REGULATORYASSETSANDLIABILITIES</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - COMMON EQUITY (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYTables</Role>
      <ShortName>COMMON EQUITY (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/COMMONEQUITY</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - SHORT-TERM DEBT AND LINES OF CREDIT (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SHORTTERMDEBTANDLINESOFCREDITTables</Role>
      <ShortName>SHORT-TERM DEBT AND LINES OF CREDIT (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/SHORTTERMDEBTANDLINESOFCREDIT</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - LONG-TERM DEBT (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/LONGTERMDEBTTables</Role>
      <ShortName>LONG-TERM DEBT (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/LONGTERMDEBT</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - MATERIALS, SUPPLIES, AND INVENTORIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/MATERIALSSUPPLIESANDINVENTORIESTables</Role>
      <ShortName>MATERIALS, SUPPLIES, AND INVENTORIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/MATERIALSSUPPLIESANDINVENTORIES</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - INCOME TAXES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INCOMETAXESTables</Role>
      <ShortName>INCOME TAXES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/INCOMETAXES</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - FAIR VALUE MEASUREMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTSTables</Role>
      <ShortName>FAIR VALUE MEASUREMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTS</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - DERIVATIVE INSTRUMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTSTables</Role>
      <ShortName>DERIVATIVE INSTRUMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTS</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - GUARANTEES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GUARANTEESTables</Role>
      <ShortName>GUARANTEES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/GUARANTEES</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - EMPLOYEE BENEFITS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/EMPLOYEEBENEFITSTables</Role>
      <ShortName>EMPLOYEE BENEFITS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/EMPLOYEEBENEFITS</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - GOODWILL AND INTANGIBLES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLESTables</Role>
      <ShortName>GOODWILL AND INTANGIBLES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLES</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATESTables</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATES</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - SEGMENT INFORMATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SEGMENTINFORMATIONTables</Role>
      <ShortName>SEGMENT INFORMATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/SEGMENTINFORMATION</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - VARIABLE INTEREST ENTITIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/VARIABLEINTERESTENTITIESTables</Role>
      <ShortName>VARIABLE INTEREST ENTITIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/VARIABLEINTERESTENTITIES</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - COMMITMENTS AND CONTINGENCIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMITMENTSANDCONTINGENCIESTables</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/COMMITMENTSANDCONTINGENCIES</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - SUPPLEMENTAL CASH FLOW INFORMATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SUPPLEMENTALCASHFLOWINFORMATIONTables</Role>
      <ShortName>SUPPLEMENTAL CASH FLOW INFORMATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/SUPPLEMENTALCASHFLOWINFORMATION</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - REGULATORY ENVIRONMENT (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTTables</Role>
      <ShortName>REGULATORY ENVIRONMENT (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENT</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - OTHER INCOME, NET (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OTHERINCOMENETTables</Role>
      <ShortName>OTHER INCOME, NET (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/OTHERINCOMENET</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - GENERAL INFORMATION - GENERAL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GENERALINFORMATIONGENERALDetails</Role>
      <ShortName>GENERAL INFORMATION - GENERAL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - GENERAL INFORMATION - INVESTMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GENERALINFORMATIONINVESTMENTSDetails</Role>
      <ShortName>GENERAL INFORMATION - INVESTMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - ACQUISITIONS - WESTON 4 (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/ACQUISITIONSWESTON4Details</Role>
      <ShortName>ACQUISITIONS - WESTON 4 (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - ACQUISITIONS - WHITETAIL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/ACQUISITIONSWHITETAILDetails</Role>
      <ShortName>ACQUISITIONS - WHITETAIL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - ACQUISITIONS - HARDIN III (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/ACQUISITIONSHARDINIIIDetails</Role>
      <ShortName>ACQUISITIONS - HARDIN III (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - DISPOSITION - PGL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DISPOSITIONPGLDetails</Role>
      <ShortName>DISPOSITION - PGL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - OPERATING REVENUES - DISAGGREGATION OF OPERATING REVENUES BY SEGMENT (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESDISAGGREGATIONOFOPERATINGREVENUESBYSEGMENTDetails</Role>
      <ShortName>OPERATING REVENUES - DISAGGREGATION OF OPERATING REVENUES BY SEGMENT (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - OPERATING REVENUES - DISAGGREGATION OF ELECTRIC UTILITY OPERATING REVENUES BY CUSTOMER CLASS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESDISAGGREGATIONOFELECTRICUTILITYOPERATINGREVENUESBYCUSTOMERCLASSDetails</Role>
      <ShortName>OPERATING REVENUES - DISAGGREGATION OF ELECTRIC UTILITY OPERATING REVENUES BY CUSTOMER CLASS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - OPERATING REVENUES - DISAGGREGATION OF NATURAL GAS UTILITY OPERATING REVENUES BY CUSTOMER CLASS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESDISAGGREGATIONOFNATURALGASUTILITYOPERATINGREVENUESBYCUSTOMERCLASSDetails</Role>
      <ShortName>OPERATING REVENUES - DISAGGREGATION OF NATURAL GAS UTILITY OPERATING REVENUES BY CUSTOMER CLASS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - OPERATING REVENUES - OTHER NON-UTILITY OPERATING REVENUES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESOTHERNONUTILITYOPERATINGREVENUESDetails</Role>
      <ShortName>OPERATING REVENUES - OTHER NON-UTILITY OPERATING REVENUES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - OPERATING REVENUES - OTHER OPERATING REVENUES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OPERATINGREVENUESOTHEROPERATINGREVENUESDetails</Role>
      <ShortName>OPERATING REVENUES - OTHER OPERATING REVENUES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - CREDIT LOSSES - GROSS RECEIVABLES AND RELATED ALLOWANCES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CREDITLOSSESGROSSRECEIVABLESANDRELATEDALLOWANCESDetails</Role>
      <ShortName>CREDIT LOSSES - GROSS RECEIVABLES AND RELATED ALLOWANCES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - CREDIT LOSSES - ROLLFORWARD OF ALLOWANCES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/CREDITLOSSESROLLFORWARDOFALLOWANCESDetails</Role>
      <ShortName>CREDIT LOSSES - ROLLFORWARD OF ALLOWANCES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - REGULATORY ASSETS AND LIABILITIES - REGULATORY ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYASSETSANDLIABILITIESREGULATORYASSETSDetails</Role>
      <ShortName>REGULATORY ASSETS AND LIABILITIES - REGULATORY ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - REGULATORY ASSETS AND LIABILITIES - REGULATORY LIABILITIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYASSETSANDLIABILITIESREGULATORYLIABILITIESDetails</Role>
      <ShortName>REGULATORY ASSETS AND LIABILITIES - REGULATORY LIABILITIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT - PLANT TO BE RETIRED - OAK CREEK POWER PLANT UNITS 7 AND 8 (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/PROPERTYPLANTANDEQUIPMENTPLANTTOBERETIREDOAKCREEKPOWERPLANTUNITS7AND8Details</Role>
      <ShortName>PROPERTY, PLANT, AND EQUIPMENT - PLANT TO BE RETIRED - OAK CREEK POWER PLANT UNITS 7 AND 8 (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT - SAMSON AND DELILAH - STORM DAMAGE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/PROPERTYPLANTANDEQUIPMENTSAMSONANDDELILAHSTORMDAMAGEDetails</Role>
      <ShortName>PROPERTY, PLANT, AND EQUIPMENT - SAMSON AND DELILAH - STORM DAMAGE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - PROPERTY, PLANT, AND EQUIPMENT - PGL IMPAIRMENT (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/PROPERTYPLANTANDEQUIPMENTPGLIMPAIRMENTDetails</Role>
      <ShortName>PROPERTY, PLANT, AND EQUIPMENT - PGL IMPAIRMENT (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - COMMON EQUITY - STOCK-BASED COMPENSATION AWARDS GRANTED (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYSTOCKBASEDCOMPENSATIONAWARDSGRANTEDDetails</Role>
      <ShortName>COMMON EQUITY - STOCK-BASED COMPENSATION AWARDS GRANTED (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - COMMON EQUITY - ATM AND FORWARD SALES CONTRACTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYATMANDFORWARDSALESCONTRACTSDetails</Role>
      <ShortName>COMMON EQUITY - ATM AND FORWARD SALES CONTRACTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - COMMON EQUITY - COMMON STOCK ISSUED (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYCOMMONSTOCKISSUEDDetails</Role>
      <ShortName>COMMON EQUITY - COMMON STOCK ISSUED (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9955553 - Disclosure - COMMON EQUITY - COMMON STOCK DIVIDENDS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYCOMMONSTOCKDIVIDENDSDetails</Role>
      <ShortName>COMMON EQUITY - COMMON STOCK DIVIDENDS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9955554 - Disclosure - COMMON EQUITY - EPS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMONEQUITYEPSDetails</Role>
      <ShortName>COMMON EQUITY - EPS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9955555 - Disclosure - SHORT-TERM DEBT AND LINES OF CREDIT - SHORT-TERM BORROWINGS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SHORTTERMDEBTANDLINESOFCREDITSHORTTERMBORROWINGSDetails</Role>
      <ShortName>SHORT-TERM DEBT AND LINES OF CREDIT - SHORT-TERM BORROWINGS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9955556 - Disclosure - SHORT-TERM DEBT AND LINES OF CREDIT - REVOLVING CREDIT FACILITIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SHORTTERMDEBTANDLINESOFCREDITREVOLVINGCREDITFACILITIESDetails</Role>
      <ShortName>SHORT-TERM DEBT AND LINES OF CREDIT - REVOLVING CREDIT FACILITIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9955557 - Disclosure - LONG-TERM DEBT - CONVERTIBLE DEBT (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/LONGTERMDEBTCONVERTIBLEDEBTDetails</Role>
      <ShortName>LONG-TERM DEBT - CONVERTIBLE DEBT (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9955558 - Disclosure - LONG-TERM DEBT - ISSUANCES AND REDEMPTIONS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/LONGTERMDEBTISSUANCESANDREDEMPTIONSDetails</Role>
      <ShortName>LONG-TERM DEBT - ISSUANCES AND REDEMPTIONS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9955559 - Disclosure - MATERIALS, SUPPLIES, AND INVENTORIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/MATERIALSSUPPLIESANDINVENTORIESDetails</Role>
      <ShortName>MATERIALS, SUPPLIES, AND INVENTORIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/MATERIALSSUPPLIESANDINVENTORIESTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9955560 - Disclosure - INCOME TAXES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INCOMETAXESDetails</Role>
      <ShortName>INCOME TAXES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/INCOMETAXESTables</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9955561 - Disclosure - FAIR VALUE MEASUREMENTS - ASSETS AND LIABILITIES MEASURED ON A RECURRING BASIS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTSASSETSANDLIABILITIESMEASUREDONARECURRINGBASISDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - ASSETS AND LIABILITIES MEASURED ON A RECURRING BASIS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9955562 - Disclosure - FAIR VALUE MEASUREMENTS - UNREALIZED GAIN OR LOSS ON INVESTMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTSUNREALIZEDGAINORLOSSONINVESTMENTSDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - UNREALIZED GAIN OR LOSS ON INVESTMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9955563 - Disclosure - FAIR VALUE MEASUREMENTS - LEVEL 3 RECONCILIATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTSLEVEL3RECONCILIATIONDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - LEVEL 3 RECONCILIATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9955564 - Disclosure - FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/FAIRVALUEMEASUREMENTSFINANCIALINSTRUMENTSDetails</Role>
      <ShortName>FAIR VALUE MEASUREMENTS - FINANCIAL INSTRUMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9955565 - Disclosure - DERIVATIVE INSTRUMENTS - DERIVATIVE ASSETS AND LIABILITIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTSDERIVATIVEASSETSANDLIABILITIESDetails</Role>
      <ShortName>DERIVATIVE INSTRUMENTS - DERIVATIVE ASSETS AND LIABILITIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9955566 - Disclosure - DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTSGAINSLOSSESANDNOTIONALVOLUMESDetails</Role>
      <ShortName>DERIVATIVE INSTRUMENTS - GAINS (LOSSES) AND NOTIONAL VOLUMES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9955567 - Disclosure - DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/DERIVATIVEINSTRUMENTSBALANCESHEETOFFSETTINGDetails</Role>
      <ShortName>DERIVATIVE INSTRUMENTS - BALANCE SHEET OFFSETTING (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9955568 - Disclosure - GUARANTEES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GUARANTEESDetails</Role>
      <ShortName>GUARANTEES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/GUARANTEESTables</ParentRole>
      <Position>93</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9955569 - Disclosure - EMPLOYEE BENEFITS-COSTS AND CONTRIBUTIONS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/EMPLOYEEBENEFITSCOSTSANDCONTRIBUTIONSDetails</Role>
      <ShortName>EMPLOYEE BENEFITS-COSTS AND CONTRIBUTIONS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9955570 - Disclosure - GOODWILL AND INTANGIBLES - GOODWILL (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLESGOODWILLDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLES - GOODWILL (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>9955571 - Disclosure - GOODWILL AND INTANGIBLES - INDEFINITE LIVED INTANGIBLE ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLESINDEFINITELIVEDINTANGIBLEASSETSDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLES - INDEFINITE LIVED INTANGIBLE ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>9955572 - Disclosure - GOODWILL AND INTANGIBLES - FINITE-LIVED INTANGIBLE ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLESFINITELIVEDINTANGIBLEASSETSDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLES - FINITE-LIVED INTANGIBLE ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>9955573 - Disclosure - GOODWILL AND INTANGIBLES - INTANGIBLE LIABILITIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/GOODWILLANDINTANGIBLESINTANGIBLELIABILITIESDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLES - INTANGIBLE LIABILITIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>9955574 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES - CHANGES TO INVESTMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATESCHANGESTOINVESTMENTSDetails</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES - CHANGES TO INVESTMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>9955575 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES - RELATED PARTY TRANSACTIONS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATESRELATEDPARTYTRANSACTIONSDetails</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES - RELATED PARTY TRANSACTIONS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>9955576 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES - RECEIVABLES AND PAYABLES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATESRECEIVABLESANDPAYABLESDetails</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES - RECEIVABLES AND PAYABLES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>9955577 - Disclosure - INVESTMENT IN TRANSMISSION AFFILIATES - SUMMARIZED FINANCIAL DATA (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/INVESTMENTINTRANSMISSIONAFFILIATESSUMMARIZEDFINANCIALDATADetails</Role>
      <ShortName>INVESTMENT IN TRANSMISSION AFFILIATES - SUMMARIZED FINANCIAL DATA (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>9955578 - Disclosure - SEGMENT INFORMATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SEGMENTINFORMATIONDetails</Role>
      <ShortName>SEGMENT INFORMATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/SEGMENTINFORMATIONTables</ParentRole>
      <Position>103</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>9955579 - Disclosure - VARIABLE INTEREST ENTITIES - WEPCO ENVIRONMENTAL TRUST (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/VARIABLEINTERESTENTITIESWEPCOENVIRONMENTALTRUSTDetails</Role>
      <ShortName>VARIABLE INTEREST ENTITIES - WEPCO ENVIRONMENTAL TRUST (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>9955580 - Disclosure - VARIABLE INTEREST ENTITIES - TRANSMISSION AFFILIATES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/VARIABLEINTERESTENTITIESTRANSMISSIONAFFILIATESDetails</Role>
      <ShortName>VARIABLE INTEREST ENTITIES - TRANSMISSION AFFILIATES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>9955581 - Disclosure - COMMITMENTS AND CONTINGENCIES - UNCONDITIONAL PURCHASE OBLIGATIONS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMITMENTSANDCONTINGENCIESUNCONDITIONALPURCHASEOBLIGATIONSDetails</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES - UNCONDITIONAL PURCHASE OBLIGATIONS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>9955582 - Disclosure - COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL MATTERS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/COMMITMENTSANDCONTINGENCIESENVIRONMENTALMATTERSDetails</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES - ENVIRONMENTAL MATTERS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>9955583 - Disclosure - SUPPLEMENTAL CASH FLOW INFORMATION - ADDITIONAL INFORMATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SUPPLEMENTALCASHFLOWINFORMATIONADDITIONALINFORMATIONDetails</Role>
      <ShortName>SUPPLEMENTAL CASH FLOW INFORMATION - ADDITIONAL INFORMATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>9955584 - Disclosure - SUPPLEMENTAL CASH FLOW INFORMATION - RECONCILIATION OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/SUPPLEMENTALCASHFLOWINFORMATIONRECONCILIATIONOFCASHCASHEQUIVALENTSANDRESTRICTEDCASHDetails</Role>
      <ShortName>SUPPLEMENTAL CASH FLOW INFORMATION - RECONCILIATION OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>9955585 - Disclosure - REGULATORY ENVIRONMENT - WI 2027 AND 2028 RATE CASES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTWI2027AND2028RATECASESDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - WI 2027 AND 2028 RATE CASES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>9955586 - Disclosure - REGULATORY ENVIRONMENT - WE VLC AND BESPOKE RESOURCES TARIFFS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTWEVLCANDBESPOKERESOURCESTARIFFSDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - WE VLC AND BESPOKE RESOURCES TARIFFS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>9955587 - Disclosure - REGULATORY ENVIRONMENT - PGL AND NSG 2026 RATE APPLICATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTPGLANDNSG2026RATEAPPLICATIONDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - PGL AND NSG 2026 RATE APPLICATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>9955588 - Disclosure - REGULATORY ENVIRONMENT - PGL AND NSG 2023 RATE ORDER (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTPGLANDNSG2023RATEORDERDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - PGL AND NSG 2023 RATE ORDER (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>9955589 - Disclosure - REGULATORY ENVIRONMENT - PGL AND NSG UEA RIDER (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTPGLANDNSGUEARIDERDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - PGL AND NSG UEA RIDER (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>9955590 - Disclosure - REGULATORY ENVIRONMENT - PGL QIP RIDER (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTPGLQIPRIDERDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - PGL QIP RIDER (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>9955591 - Disclosure - REGULATORY ENVIRONMENT - UEA AND QIP RIDERS SETTLEMENT (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTUEAANDQIPRIDERSSETTLEMENTDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - UEA AND QIP RIDERS SETTLEMENT (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>9955592 - Disclosure - REGULATORY ENVIRONMENT - UMERC AREP (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/REGULATORYENVIRONMENTUMERCAREPDetails</Role>
      <ShortName>REGULATORY ENVIRONMENT - UMERC AREP (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="wec-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>9955593 - Disclosure - OTHER INCOME, NET (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.wecenergygroup.com/role/OTHERINCOMENETDetails</Role>
      <ShortName>OTHER INCOME, NET (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.wecenergygroup.com/role/OTHERINCOMENETTables</ParentRole>
      <Position>118</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" isDefinitelyFs="true" isUsgaap="true" original="wec-20260331.htm">wec-20260331.htm</File>
    <File>wec-20260331.xsd</File>
    <File>wec-20260331_cal.xml</File>
    <File>wec-20260331_def.xml</File>
    <File>wec-20260331_lab.xml</File>
    <File>wec-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>wec-20260331_g1.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="1667">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="30">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
