<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>168</ContextCount>
  <ElementCount>374</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>60</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>5</UnitCount>
  <MyReports>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0000002 - Statement - Consolidated Statements of Financial Position</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ConsolidatedStatementsOfFinancialPosition</Role>
      <ShortName>Consolidated Statements of Financial Position</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>0000003 - Statement - Consolidated Statements of Operations and Comprehensive Income (Loss)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ConsolidatedStatementsOfOperationsAndComprehensiveIncomeLoss</Role>
      <ShortName>Consolidated Statements of Operations and Comprehensive Income (Loss)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>0000004 - Statement - Consolidated Statements of Changes in Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ConsolidatedStatementsOfChangesInEquity</Role>
      <ShortName>Consolidated Statements of Changes in Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>0000005 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>0000006 - Disclosure - NATURE OF OPERATIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/NatureOfOperations</Role>
      <ShortName>NATURE OF OPERATIONS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>0000007 - Disclosure - BASIS OF PRESENTATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/BasisOfPresentation</Role>
      <ShortName>BASIS OF PRESENTATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>0000008 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SignificantAccountingPolicies</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>0000009 - Disclosure - RECENT ACCOUNTING PRONOUNCEMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RecentAccountingPronouncements</Role>
      <ShortName>RECENT ACCOUNTING PRONOUNCEMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>000010 - Disclosure - DISPOSITION OF EXPLORATION AND EVALUATION ASSETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/DispositionOfExplorationAndEvaluationAssets</Role>
      <ShortName>DISPOSITION OF EXPLORATION AND EVALUATION ASSETS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>000011 - Disclosure - EXPLORATION AND EVALUATION ASSETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ExplorationAndEvaluationAssets</Role>
      <ShortName>EXPLORATION AND EVALUATION ASSETS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>000012 - Disclosure - ROYALTY RECEIVABLE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RoyaltyReceivable</Role>
      <ShortName>ROYALTY RECEIVABLE</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>000013 - Disclosure - INVESTMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/INVESTMENTS</Role>
      <ShortName>INVESTMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>000014 - Disclosure - SHARE CAPITAL AND SHARE-BASED PAYMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndShareBasedPayments</Role>
      <ShortName>SHARE CAPITAL AND SHARE-BASED PAYMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>000015 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalances</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>000016 - Disclosure - COMMITMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/COMMITMENTS</Role>
      <ShortName>COMMITMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>000017 - Disclosure - FINANCIAL INSTRUMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstruments</Role>
      <ShortName>FINANCIAL INSTRUMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>000018 - Disclosure - CAPITAL MANAGEMENT</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/CapitalManagement</Role>
      <ShortName>CAPITAL MANAGEMENT</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>000019 - Disclosure - SUPPLEMENTARY CASH FLOW DISCLOSURES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SupplementaryCashFlowDisclosures</Role>
      <ShortName>SUPPLEMENTARY CASH FLOW DISCLOSURES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>000020 - Disclosure - INCOME TAXES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxes</Role>
      <ShortName>INCOME TAXES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>000021 - Disclosure - SEGMENTED INFORMATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SegmentedInformation</Role>
      <ShortName>SEGMENTED INFORMATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>000022 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SignificantAccountingPoliciesPolicies</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>000023 - Disclosure - BASIS OF PRESENTATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/BasisOfPresentationTables</Role>
      <ShortName>BASIS OF PRESENTATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/BasisOfPresentation</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>000024 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SignificantAccountingPoliciesTables</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>000025 - Disclosure - DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/DispositionOfExplorationAndEvaluationAssetsTables</Role>
      <ShortName>DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/DispositionOfExplorationAndEvaluationAssets</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>000026 - Disclosure - EXPLORATION AND EVALUATION ASSETS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ExplorationAndEvaluationAssetsTables</Role>
      <ShortName>EXPLORATION AND EVALUATION ASSETS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/ExplorationAndEvaluationAssets</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>000027 - Disclosure - ROYALTY RECEIVABLE (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RoyaltyReceivableTables</Role>
      <ShortName>ROYALTY RECEIVABLE (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/RoyaltyReceivable</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>000028 - Disclosure - INVESTMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/InvestmentsTables</Role>
      <ShortName>INVESTMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/INVESTMENTS</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>000029 - Disclosure - SHARE CAPITAL AND SHARE-BASED PAYMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndShareBasedPaymentsTables</Role>
      <ShortName>SHARE CAPITAL AND SHARE-BASED PAYMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/ShareCapitalAndShareBasedPayments</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>000030 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalancesTables</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/RelatedPartyTransactionsAndBalances</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>000031 - Disclosure - FINANCIAL INSTRUMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstrumentsTables</Role>
      <ShortName>FINANCIAL INSTRUMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/FinancialInstruments</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>000032 - Disclosure - SUPPLEMENTARY CASH FLOW DISCLOSURES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SupplementaryCashFlowDisclosuresTables</Role>
      <ShortName>SUPPLEMENTARY CASH FLOW DISCLOSURES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/SupplementaryCashFlowDisclosures</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>000033 - Disclosure - INCOME TAXES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxesTables</Role>
      <ShortName>INCOME TAXES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/IncomeTaxes</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>000034 - Disclosure - SEGMENTED INFORMATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SegmentedInformationTables</Role>
      <ShortName>SEGMENTED INFORMATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://coral.com/role/SegmentedInformation</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>000035 - Disclosure - NATURE OF OPERATIONS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/NatureOfOperationsDetailsNarrative</Role>
      <ShortName>NATURE OF OPERATIONS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/NatureOfOperations</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>000036 - Disclosure - BASIS OF PRESENTATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/BasisOfPresentationDetails</Role>
      <ShortName>BASIS OF PRESENTATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/BasisOfPresentationTables</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>000037 - Disclosure - BASIS OF PRESENTATION (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/BasisOfPresentationDetailsNarrative</Role>
      <ShortName>BASIS OF PRESENTATION (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/BasisOfPresentationTables</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>000038 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SignificantAccountingPoliciesDetails</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/SignificantAccountingPoliciesTables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>000039 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SignificantAccountingPoliciesDetails1</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/SignificantAccountingPoliciesTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>000040 - Disclosure - DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/DispositionOfExplorationAndEvaluationAssetsDetails</Role>
      <ShortName>DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/DispositionOfExplorationAndEvaluationAssetsTables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>000041 - Disclosure - DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/DispositionOfExplorationAndEvaluationAssetsDetailsNarrative</Role>
      <ShortName>DISPOSITION OF EXPLORATION AND EVALUATION ASSETS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/DispositionOfExplorationAndEvaluationAssetsTables</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>000042 - Disclosure - EXPLORATION AND EVALUATION ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ExplorationAndEvaluationAssetsDetails</Role>
      <ShortName>EXPLORATION AND EVALUATION ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/ExplorationAndEvaluationAssetsTables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>000043 - Disclosure - EXPLORATION AND EVALUATION ASSETS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ExplorationAndEvaluationAssetsDetailsNarrative</Role>
      <ShortName>EXPLORATION AND EVALUATION ASSETS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/ExplorationAndEvaluationAssetsTables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>000044 - Disclosure - ROYALTY RECEIVABLE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RoyaltyReceivableDetails</Role>
      <ShortName>ROYALTY RECEIVABLE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/RoyaltyReceivableTables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>000045 - Disclosure - INVESTMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/InvestmentsDetails</Role>
      <ShortName>INVESTMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/InvestmentsTables</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>000046 - Disclosure - INVESTMENTS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/InvestmentsDetailsNarrative</Role>
      <ShortName>INVESTMENTS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/InvestmentsTables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>000047 - Disclosure - SHARE CAPITAL AND SHAREBASED PAYMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndSharebasedPaymentsDetails</Role>
      <ShortName>SHARE CAPITAL AND SHAREBASED PAYMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>000048 - Disclosure - SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndSharebasedPaymentsDetails1</Role>
      <ShortName>SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>000049 - Disclosure - SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndSharebasedPaymentsDetails2</Role>
      <ShortName>SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>000050 - Disclosure - SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndSharebasedPaymentsDetails3</Role>
      <ShortName>SHARE CAPITAL AND SHAREBASED PAYMENTS (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>000051 - Disclosure - SHARE CAPITAL AND SHAREBASED PAYMENTS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/ShareCapitalAndSharebasedPaymentsDetailsNarrative</Role>
      <ShortName>SHARE CAPITAL AND SHAREBASED PAYMENTS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>000052 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalancesDetails</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/RelatedPartyTransactionsAndBalancesTables</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>000053 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalancesDetails1</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/RelatedPartyTransactionsAndBalancesTables</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>000054 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalancesDetails2</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/RelatedPartyTransactionsAndBalancesTables</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>000055 - Disclosure - RELATED PARTY TRANSACTIONS AND BALANCES (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/RelatedPartyTransactionsAndBalancesDetailsNarrative</Role>
      <ShortName>RELATED PARTY TRANSACTIONS AND BALANCES (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/RelatedPartyTransactionsAndBalancesTables</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>000056 - Disclosure - COMMITMENTS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/CommitmentsDetailsNarrative</Role>
      <ShortName>COMMITMENTS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/COMMITMENTS</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>000057 - Disclosure - FINANCIAL INSTRUMENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstrumentsDetails</Role>
      <ShortName>FINANCIAL INSTRUMENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/FinancialInstrumentsTables</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>000058 - Disclosure - FINANCIAL INSTRUMENTS (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstrumentsDetails1</Role>
      <ShortName>FINANCIAL INSTRUMENTS (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/FinancialInstrumentsTables</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>000059 - Disclosure - FINANCIAL INSTRUMENTS (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstrumentsDetails2</Role>
      <ShortName>FINANCIAL INSTRUMENTS (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/FinancialInstrumentsTables</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>000060 - Disclosure - FINANCIAL INSTRUMENTS (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/FinancialInstrumentsDetailsNarrative</Role>
      <ShortName>FINANCIAL INSTRUMENTS (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/FinancialInstrumentsTables</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>000061 - Disclosure - SUPPLEMENTARY CASH FLOW DISCLOSURES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SupplementaryCashFlowDisclosuresDetails</Role>
      <ShortName>SUPPLEMENTARY CASH FLOW DISCLOSURES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/SupplementaryCashFlowDisclosuresTables</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>000062 - Disclosure - INCOME TAXES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxesDetails</Role>
      <ShortName>INCOME TAXES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/IncomeTaxesTables</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>000063 - Disclosure - INCOME TAXES (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxesDetails1</Role>
      <ShortName>INCOME TAXES (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/IncomeTaxesTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>000064 - Disclosure - INCOME TAXES (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxesDetails2</Role>
      <ShortName>INCOME TAXES (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/IncomeTaxesTables</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>000065 - Disclosure - INCOME TAXES (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/IncomeTaxesDetailsNarrative</Role>
      <ShortName>INCOME TAXES (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/IncomeTaxesTables</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>000066 - Disclosure - SEGMENTED INFORMATION (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SegmentedInformationDetails</Role>
      <ShortName>SEGMENTED INFORMATION (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/SegmentedInformationTables</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="coral-20200131.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>000067 - Disclosure - SEGMENTED INFORMATION (Details Narrative)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://coral.com/role/SegmentedInformationDetailsNarrative</Role>
      <ShortName>SEGMENTED INFORMATION (Details Narrative)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://coral.com/role/SegmentedInformationTables</ParentRole>
      <Position>67</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>coral-20200131.xml</File>
    <File>coral-20200131.xsd</File>
    <File>coral-20200131_cal.xml</File>
    <File>coral-20200131_def.xml</File>
    <File>coral-20200131_lab.xml</File>
    <File>coral-20200131_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.ifrs.org/taxonomy/2019-03-27/ifrs-full</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2019-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
