<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.3.1.900</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>1006</ContextCount>
  <ElementCount>778</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>228</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>26</UnitCount>
  <MyReports>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001501 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002000 - Statement - Consolidated Statements of Earnings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedStatementsOfEarnings</Role>
      <ShortName>Consolidated Statements of Earnings</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1003000 - Statement - Consolidated Statements of Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>Consolidated Statements of Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1004000 - Statement - Consolidated Statements of Changes in Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedStatementsOfChangesInShareholdersEquity</Role>
      <ShortName>Consolidated Statements of Changes in Shareholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1005000 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Description of Business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DescriptionOfBusiness</Role>
      <ShortName>Description of Business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2112100 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SignificantAccountingPolicies</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2122100 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/Acquisitions</Role>
      <ShortName>Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2123100 - Disclosure - Significant New Business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SignificantNewBusiness</Role>
      <ShortName>Significant New Business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2124100 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/Investments</Role>
      <ShortName>Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2125100 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2126100 - Disclosure - Derivative Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DerivativeInstruments</Role>
      <ShortName>Derivative Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2127100 - Disclosure - Reinsurance Balances Recoverable</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverable</Role>
      <ShortName>Reinsurance Balances Recoverable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2128100 - Disclosure - Losses and Loss Adjustment Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpenses</Role>
      <ShortName>Losses and Loss Adjustment Expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2129100 - Disclosure - Policy Benefits for Life and Annuity Contracts</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PolicyBenefitsForLifeAndAnnuityContracts</Role>
      <ShortName>Policy Benefits for Life and Annuity Contracts</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2130100 - Disclosure - Premiums Written and Earned</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PremiumsWrittenAndEarned</Role>
      <ShortName>Premiums Written and Earned</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2131100 - Disclosure - Goodwill, Intangible Assets and Deferred Charge</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredCharge</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charge</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2132100 - Disclosure - Loans Payable</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LoansPayable</Role>
      <ShortName>Loans Payable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2133100 - Disclosure - Noncontrolling Interests</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/NoncontrollingInterests</Role>
      <ShortName>Noncontrolling Interests</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2134100 - Disclosure - Share Capital</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ShareCapital</Role>
      <ShortName>Share Capital</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2135100 - Disclosure - Earnings Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EarningsPerShare</Role>
      <ShortName>Earnings Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2136100 - Disclosure - Employee Benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefits</Role>
      <ShortName>Employee Benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2137100 - Disclosure - Taxation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/Taxation</Role>
      <ShortName>Taxation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2140100 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2141100 - Disclosure - Dividend Restrictions and Statutory Requirements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DividendRestrictionsAndStatutoryRequirements</Role>
      <ShortName>Dividend Restrictions and Statutory Requirements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2142100 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2143100 - Disclosure - Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformation</Role>
      <ShortName>Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2144100 - Disclosure - Unaudited Condensed Quarterly Financial Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/UnauditedCondensedQuarterlyFinancialData</Role>
      <ShortName>Unaudited Condensed Quarterly Financial Data</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2145100 - Disclosure - Schedule I - Summary of Investments Other Than Investments in Related Parties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleISummaryOfInvestmentsOtherThanInvestmentsInRelatedParties</Role>
      <ShortName>Schedule I - Summary of Investments Other Than Investments in Related Parties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2149100 - Disclosure - Schedule II - Condensed Financial Statements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiCondensedFinancialStatements</Role>
      <ShortName>Schedule II - Condensed Financial Statements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2150100 - Disclosure - Schedule III - Supplementary Insurance Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiiSupplementaryInsuranceInformation</Role>
      <ShortName>Schedule III - Supplementary Insurance Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2151100 - Disclosure - Schedule IV - Reinsurance</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIvReinsurance</Role>
      <ShortName>Schedule IV - Reinsurance</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2152100 - Disclosure - Schedule VI - Supplementary Information Concerning Property/Casualty Insurance Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleViSupplementaryInformationConcerningPropertyCasualtyInsuranceOperations</Role>
      <ShortName>Schedule VI - Supplementary Information Concerning Property/Casualty Insurance Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2212201 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SignificantAccountingPoliciesPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2322301 - Disclosure - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsTables</Role>
      <ShortName>Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/Acquisitions</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2324301 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsTables</Role>
      <ShortName>Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/Investments</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2325301 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/FairValueMeasurements</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2326301 - Disclosure - Derivative Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DerivativeInstrumentsTables</Role>
      <ShortName>Derivative Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/DerivativeInstruments</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2327301 - Disclosure - Reinsurance Balances Recoverable (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverableTables</Role>
      <ShortName>Reinsurance Balances Recoverable (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverable</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2328301 - Disclosure - Losses and Loss Adjustment Expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesTables</Role>
      <ShortName>Losses and Loss Adjustment Expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpenses</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2329301 - Disclosure - Policy Benefits for Life and Annuity Contracts (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PolicyBenefitsForLifeAndAnnuityContractsTables</Role>
      <ShortName>Policy Benefits for Life and Annuity Contracts (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/PolicyBenefitsForLifeAndAnnuityContracts</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2330301 - Disclosure - Premiums Written and Earned (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PremiumsWrittenAndEarnedTables</Role>
      <ShortName>Premiums Written and Earned (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/PremiumsWrittenAndEarned</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2331301 - Disclosure - Goodwill, Intangible Assets and Deferred Charges (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredChargesTables</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charges (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredCharge</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2332301 - Disclosure - Loans Payable (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LoansPayableTables</Role>
      <ShortName>Loans Payable (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/LoansPayable</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2333301 - Disclosure - Noncontrolling Interests (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/NoncontrollingInterestsTables</Role>
      <ShortName>Noncontrolling Interests (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/NoncontrollingInterests</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2335301 - Disclosure - Earnings Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/EarningsPerShare</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2336301 - Disclosure - Employee Benefits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsTables</Role>
      <ShortName>Employee Benefits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/EmployeeBenefits</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2337301 - Disclosure - Taxation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationTables</Role>
      <ShortName>Taxation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/Taxation</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2341301 - Disclosure - Dividend Restrictions and Statutory Requirements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DividendRestrictionsAndStatutoryRequirementsTables</Role>
      <ShortName>Dividend Restrictions and Statutory Requirements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/DividendRestrictionsAndStatutoryRequirements</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2342301 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/CommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/CommitmentsAndContingencies</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2343301 - Disclosure - Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformationTables</Role>
      <ShortName>Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/SegmentInformation</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2344301 - Disclosure - Unaudited Condensed Quarterly Financial Data (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/UnauditedCondensedQuarterlyFinancialDataTables</Role>
      <ShortName>Unaudited Condensed Quarterly Financial Data (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/UnauditedCondensedQuarterlyFinancialData</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2406401 - Disclosure - Description of Business - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DescriptionOfBusinessAdditionalInformationDetail</Role>
      <ShortName>Description of Business - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2412402 - Disclosure - Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SignificantAccountingPoliciesDetails</Role>
      <ShortName>Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/SignificantAccountingPoliciesPolicies</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2422402 - Disclosure - Acquisitions - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsAdditionalInformationDetail</Role>
      <ShortName>Acquisitions - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2422403 - Disclosure - Acquisitions - Purchase Price and Fair Value of Assets Acquired (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsPurchasePriceAndFairValueOfAssetsAcquiredDetail</Role>
      <ShortName>Acquisitions - Purchase Price and Fair Value of Assets Acquired (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2422404 - Disclosure - Acquisitions - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed as of Date of Acquisition (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsSummaryOfEstimatedFairValuesOfAssetsAcquiredAndLiabilitiesAssumedAsOfDateOfAcquisitionDetail</Role>
      <ShortName>Acquisitions - Summary of Estimated Fair Values of Assets Acquired and Liabilities Assumed as of Date of Acquisition (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2422405 - Disclosure - Acquisitions - Summary of Intangible Assets Recorded in Connection with Acquisition (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsSummaryOfIntangibleAssetsRecordedInConnectionWithAcquisitionDetail</Role>
      <ShortName>Acquisitions - Summary of Intangible Assets Recorded in Connection with Acquisition (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2422406 - Disclosure - Acquisitions - Pro Forma Condensed Combined Statement of Earnings (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsProFormaCondensedCombinedStatementOfEarningsDetail</Role>
      <ShortName>Acquisitions - Pro Forma Condensed Combined Statement of Earnings (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2422407 - Disclosure - Acquisitions - Summary of Pro Forma Adjustments to Pro Forma Condensed Statement of Earnings (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/AcquisitionsSummaryOfProFormaAdjustmentsToProFormaCondensedStatementOfEarningsDetail</Role>
      <ShortName>Acquisitions - Summary of Pro Forma Adjustments to Pro Forma Condensed Statement of Earnings (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2423401 - Disclosure - Significant New Business - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SignificantNewBusinessAdditionalInformationDetail</Role>
      <ShortName>Significant New Business - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2424402 - Disclosure - Investments - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsAdditionalInformationDetail</Role>
      <ShortName>Investments - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2424403 - Disclosure - Investments - Estimated Fair Values of Investments in Fixed Maturity Investments, Short-Term Investments and Equities, Trading Securities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsEstimatedFairValuesOfInvestmentsInFixedMaturityInvestmentsShortTermInvestmentsAndEquitiesTradingSecuritiesDetail</Role>
      <ShortName>Investments - Estimated Fair Values of Investments in Fixed Maturity Investments, Short-Term Investments and Equities, Trading Securities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2424404 - Disclosure - Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity Classified as Trading (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsAmortizedCostAndEstimatedFairValuesOfCompanysFixedMaturityClassifiedAsTradingDetail</Role>
      <ShortName>Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity Classified as Trading (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2424405 - Disclosure - Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity Investments Classified as Held-to-Maturity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsAmortizedCostAndEstimatedFairValuesOfCompanysFixedMaturityInvestmentsClassifiedAsHeldToMaturityDetail</Role>
      <ShortName>Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity Investments Classified as Held-to-Maturity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2424406 - Disclosure - Investments - Summary of Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsSummaryOfAmortizedCostAndEstimatedFairValueOfFixedMaturitiesByContractualMaturityDetail</Role>
      <ShortName>Investments - Summary of Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2424407 - Disclosure - Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity and Short-Term Investments Classified as Available-for-Sale (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsAmortizedCostAndEstimatedFairValuesOfCompanysFixedMaturityAndShortTermInvestmentsClassifiedAsAvailableForSaleDetail</Role>
      <ShortName>Investments - Amortized Cost and Estimated Fair Values of Company's Fixed Maturity and Short-Term Investments Classified as Available-for-Sale (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2424408 - Disclosure - Investments - Summary of Contractual Maturities of Company's Fixed Maturity and Short-Term Investments Classified as Available-for-Sale (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsSummaryOfContractualMaturitiesOfCompanysFixedMaturityAndShortTermInvestmentsClassifiedAsAvailableForSaleDetail</Role>
      <ShortName>Investments - Summary of Contractual Maturities of Company's Fixed Maturity and Short-Term Investments Classified as Available-for-Sale (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2424409 - Disclosure - Investments - Summary of Investments Classified as Available-for-Sale in Unrealized Loss Position as Well as Aggregate Fair Value and Gross Unrealized Loss by Length of Time (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsSummaryOfInvestmentsClassifiedAsAvailableForSaleInUnrealizedLossPositionAsWellAsAggregateFairValueAndGrossUnrealizedLossByLengthOfTimeDetail</Role>
      <ShortName>Investments - Summary of Investments Classified as Available-for-Sale in Unrealized Loss Position as Well as Aggregate Fair Value and Gross Unrealized Loss by Length of Time (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2424410 - Disclosure - Investments - Credit Ratings of Fixed Maturity and Short-Term Investments, Trading (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsCreditRatingsOfFixedMaturityAndShortTermInvestmentsTradingDetail</Role>
      <ShortName>Investments - Credit Ratings of Fixed Maturity and Short-Term Investments, Trading (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2424411 - Disclosure - Investments - Other Investments (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsOtherInvestmentsDetail</Role>
      <ShortName>Investments - Other Investments (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2424412 - Disclosure - Investments - Investments in Life Settlements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsInvestmentsInLifeSettlementsDetails</Role>
      <ShortName>Investments - Investments in Life Settlements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2424413 - Disclosure - Investments - Components of Net Realized and Unrealized Gains (Losses) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsComponentsOfNetRealizedAndUnrealizedGainsLossesDetail</Role>
      <ShortName>Investments - Components of Net Realized and Unrealized Gains (Losses) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2424414 - Disclosure - Investments - Major Categories of Net Investment Income (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsMajorCategoriesOfNetInvestmentIncomeDetail</Role>
      <ShortName>Investments - Major Categories of Net Investment Income (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2424415 - Disclosure - Investments - Schedule of Carrying Value of Restricted Investments (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/InvestmentsScheduleOfCarryingValueOfRestrictedInvestmentsDetail</Role>
      <ShortName>Investments - Schedule of Carrying Value of Restricted Investments (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2425402 - Disclosure - Fair Value Measurements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/FairValueMeasurementsAdditionalInformationDetails</Role>
      <ShortName>Fair Value Measurements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2425403 - Disclosure - Fair Value Measurements - Categorized Investments and Assets Carried at Cost or Amortized Cost and Fair Value Among Levels (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/FairValueMeasurementsCategorizedInvestmentsAndAssetsCarriedAtCostOrAmortizedCostAndFairValueAmongLevelsDetails</Role>
      <ShortName>Fair Value Measurements - Categorized Investments and Assets Carried at Cost or Amortized Cost and Fair Value Among Levels (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2425404 - Disclosure - Fair Value Measurements - Reconciliation for Investments Measured At Fair Value on Recurring Basis Level 3 (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/FairValueMeasurementsReconciliationForInvestmentsMeasuredAtFairValueOnRecurringBasisLevel3Details</Role>
      <ShortName>Fair Value Measurements - Reconciliation for Investments Measured At Fair Value on Recurring Basis Level 3 (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2426402 - Disclosure - Derivative Instruments - Forward Contracts Outstanding, Estimated Fair Value, Change in Fair Value and Realized Gains of Derivative Instruments (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DerivativeInstrumentsForwardContractsOutstandingEstimatedFairValueChangeInFairValueAndRealizedGainsOfDerivativeInstrumentsDetail</Role>
      <ShortName>Derivative Instruments - Forward Contracts Outstanding, Estimated Fair Value, Change in Fair Value and Realized Gains of Derivative Instruments (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2427402 - Disclosure - Reinsurance Balances Recoverable - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverableAdditionalInformationDetail</Role>
      <ShortName>Reinsurance Balances Recoverable - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2427403 - Disclosure - Reinsurance Balances Recoverable - Summary of Reinsurance Reserves Recoverable (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverableSummaryOfReinsuranceReservesRecoverableDetail</Role>
      <ShortName>Reinsurance Balances Recoverable - Summary of Reinsurance Reserves Recoverable (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>2427404 - Disclosure - Reinsurance Balances Recoverable - Reinsurance Balances Recoverable by Reinsurer (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverableReinsuranceBalancesRecoverableByReinsurerDetail</Role>
      <ShortName>Reinsurance Balances Recoverable - Reinsurance Balances Recoverable by Reinsurer (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>2427405 - Disclosure - Reinsurance Balances Recoverable - Summary of Provisions for Uncollectible Reinsurance Balances Recoverable by Rating of Reinsurer (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ReinsuranceBalancesRecoverableSummaryOfProvisionsForUncollectibleReinsuranceBalancesRecoverableByRatingOfReinsurerDetails</Role>
      <ShortName>Reinsurance Balances Recoverable - Summary of Provisions for Uncollectible Reinsurance Balances Recoverable by Rating of Reinsurer (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>2428402 - Disclosure - Losses and Loss Adjustment Expenses - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesAdditionalInformationDetail</Role>
      <ShortName>Losses and Loss Adjustment Expenses - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>2428403 - Disclosure - Losses and Loss Adjustment Expenses - Total Losses and Loss Adjustment Expense Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesTotalLossesAndLossAdjustmentExpenseLiabilitiesDetail</Role>
      <ShortName>Losses and Loss Adjustment Expenses - Total Losses and Loss Adjustment Expense Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>2428404 - Disclosure - Losses and Loss Adjustment Expenses - Reconciliation of Beginning and Ending Reserves for Losses and Loss Adjustment Expenses (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesReconciliationOfBeginningAndEndingReservesForLossesAndLossAdjustmentExpensesDetail</Role>
      <ShortName>Losses and Loss Adjustment Expenses - Reconciliation of Beginning and Ending Reserves for Losses and Loss Adjustment Expenses (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>2428405 - Disclosure - Losses and Loss Adjustment Expenses - Net (Reduction) Increase in Ultimate Losses and Loss Adjustment Expense Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesNetReductionIncreaseInUltimateLossesAndLossAdjustmentExpenseLiabilitiesDetail</Role>
      <ShortName>Losses and Loss Adjustment Expenses - Net (Reduction) Increase in Ultimate Losses and Loss Adjustment Expense Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/LossesAndLossAdjustmentExpensesTables</ParentRole>
      <Position>89</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>2429402 - Disclosure - Policy Benefits for Life and Annuity Contracts - Schedule of Life and Annuity Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PolicyBenefitsForLifeAndAnnuityContractsScheduleOfLifeAndAnnuityBenefitsDetail</Role>
      <ShortName>Policy Benefits for Life and Annuity Contracts - Schedule of Life and Annuity Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>2430402 - Disclosure - Premiums Written and Earned - Schedule of Net Premiums Written and Earned (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/PremiumsWrittenAndEarnedScheduleOfNetPremiumsWrittenAndEarnedDetail</Role>
      <ShortName>Premiums Written and Earned - Schedule of Net Premiums Written and Earned (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>2431400 - Disclosure - Goodwill, Intangible Assets and Deferred Charge - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredChargeAdditionalInformationDetail</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charge - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>2431402 - Disclosure - Goodwill, Intangible Assets and Deferred Charge - Schedule of Goodwill, Intangible Assets and Deferred Charges (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredChargeScheduleOfGoodwillIntangibleAssetsAndDeferredChargesDetail</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charge - Schedule of Goodwill, Intangible Assets and Deferred Charges (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>2431403 - Disclosure - Goodwill, Intangible Assets and Deferred Charge - Summary of Gross Carrying Value, Accumulated Amortization and Net Carrying Value of Intangible Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredChargeSummaryOfGrossCarryingValueAccumulatedAmortizationAndNetCarryingValueOfIntangibleAssetsDetail</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charge - Summary of Gross Carrying Value, Accumulated Amortization and Net Carrying Value of Intangible Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>2431404 - Disclosure - Goodwill, Intangible Assets and Deferred Charge - Summary of Estimated Amortization Expense of Intangible Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/GoodwillIntangibleAssetsAndDeferredChargeSummaryOfEstimatedAmortizationExpenseOfIntangibleAssetsDetail</Role>
      <ShortName>Goodwill, Intangible Assets and Deferred Charge - Summary of Estimated Amortization Expense of Intangible Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>2432402 - Disclosure - Loans Payable - Amounts of Loans Payable Outstanding, and Accrued Interest (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LoansPayableAmountsOfLoansPayableOutstandingAndAccruedInterestDetail</Role>
      <ShortName>Loans Payable - Amounts of Loans Payable Outstanding, and Accrued Interest (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>2432403 - Disclosure - Loans Payable - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/LoansPayableAdditionalInformationDetail</Role>
      <ShortName>Loans Payable - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>2433402 - Disclosure - Noncontrolling Interests - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/NoncontrollingInterestsAdditionalInformationDetail</Role>
      <ShortName>Noncontrolling Interests - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>2433403 - Disclosure - Noncontrolling Interests - Carrying Amount of Equity Attributable to Noncontrolling Interest (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/NoncontrollingInterestsCarryingAmountOfEquityAttributableToNoncontrollingInterestDetail</Role>
      <ShortName>Noncontrolling Interests - Carrying Amount of Equity Attributable to Noncontrolling Interest (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>2434401 - Disclosure - Share Capital - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ShareCapitalAdditionalInformationDetail</Role>
      <ShortName>Share Capital - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>2435402 - Disclosure - Earnings Per Share - Comparison of Basic and Diluted Earnings per Share (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EarningsPerShareComparisonOfBasicAndDilutedEarningsPerShareDetail</Role>
      <ShortName>Earnings Per Share - Comparison of Basic and Diluted Earnings per Share (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>2436402 - Disclosure - Employee Benefits - Components of Salaries and Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsComponentsOfSalariesAndBenefitsDetail</Role>
      <ShortName>Employee Benefits - Components of Salaries and Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>2436403 - Disclosure - Employee Benefits - Employee Share Awards (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsEmployeeShareAwardsDetail</Role>
      <ShortName>Employee Benefits - Employee Share Awards (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>2436404 - Disclosure - Employee Benefits - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsAdditionalInformationDetail</Role>
      <ShortName>Employee Benefits - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>2436405 - Disclosure - Employee Benefits - Summary of Company's SARs Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsSummaryOfCompanysSarsActivityDetail</Role>
      <ShortName>Employee Benefits - Summary of Company's SARs Activity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>2436406 - Disclosure - Employee Benefits - Assumptions Used to Estimate Fair Value of SARs Using Black-Scholes Option Valuation Model (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsAssumptionsUsedToEstimateFairValueOfSarsUsingBlackScholesOptionValuationModelDetail</Role>
      <ShortName>Employee Benefits - Assumptions Used to Estimate Fair Value of SARs Using Black-Scholes Option Valuation Model (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>2436407 - Disclosure - Employee Benefits - Restricted Share Units - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsRestrictedShareUnitsAdditionalInformationDetail</Role>
      <ShortName>Employee Benefits - Restricted Share Units - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>2436408 - Disclosure - Employee Benefits - Pension Plan - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/EmployeeBenefitsPensionPlanAdditionalInformationDetail</Role>
      <ShortName>Employee Benefits - Pension Plan - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>2437402 - Disclosure - Taxation - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationAdditionalInformationDetail</Role>
      <ShortName>Taxation - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>2437403 - Disclosure - Taxation - Earnings before Income Taxes (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationEarningsBeforeIncomeTaxesDetail</Role>
      <ShortName>Taxation - Earnings before Income Taxes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>2437404 - Disclosure - Taxation - Tax Expense for Income Taxes (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationTaxExpenseForIncomeTaxesDetail</Role>
      <ShortName>Taxation - Tax Expense for Income Taxes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>2437405 - Disclosure - Taxation - Reconciliation of Earnings before Income Taxes Computed by Applying Effective Rate (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationReconciliationOfEarningsBeforeIncomeTaxesComputedByApplyingEffectiveRateDetail</Role>
      <ShortName>Taxation - Reconciliation of Earnings before Income Taxes Computed by Applying Effective Rate (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>2437406 - Disclosure - Taxation - Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationComponentsOfDeferredTaxAssetsAndDeferredTaxLiabilitiesDetail</Role>
      <ShortName>Taxation - Components of Deferred Tax Assets and Deferred Tax Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>2437407 - Disclosure - Taxation - Net Operating Loss Carryforwards (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationNetOperatingLossCarryforwardsDetails</Role>
      <ShortName>Taxation - Net Operating Loss Carryforwards (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>2437408 - Disclosure - Taxation - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/TaxationReconciliationOfBeginningAndEndingAmountOfUnrecognizedTaxBenefitsDetail</Role>
      <ShortName>Taxation - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>2440401 - Disclosure - Related Party Transactions - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/RelatedPartyTransactionsAdditionalInformationDetail</Role>
      <ShortName>Related Party Transactions - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>2441402 - Disclosure - Dividend Restrictions and Statutory Requirements - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DividendRestrictionsAndStatutoryRequirementsAdditionalInformationDetail</Role>
      <ShortName>Dividend Restrictions and Statutory Requirements - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>2441403 - Disclosure - Dividend Restrictions and Statutory Requirements - Summary of Statutory Capital and Surplus (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/DividendRestrictionsAndStatutoryRequirementsSummaryOfStatutoryCapitalAndSurplusDetail</Role>
      <ShortName>Dividend Restrictions and Statutory Requirements - Summary of Statutory Capital and Surplus (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>118</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>2442402 - Disclosure - Commitments and Contingencies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/CommitmentsAndContingenciesAdditionalInformationDetail</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>119</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>2442403 - Disclosure - Commitments and Contingencies - Schedule of Future Minimum Rental Payments on Non-Cancellable Leases (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/CommitmentsAndContingenciesScheduleOfFutureMinimumRentalPaymentsOnNonCancellableLeasesDetail</Role>
      <ShortName>Commitments and Contingencies - Schedule of Future Minimum Rental Payments on Non-Cancellable Leases (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>120</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>2443402 - Disclosure - Segment Information - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformationAdditionalInformationDetail</Role>
      <ShortName>Segment Information - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>121</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>2443403 - Disclosure - Segment Information - Summary of Operations by Segment (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformationSummaryOfOperationsBySegmentDetail</Role>
      <ShortName>Segment Information - Summary of Operations by Segment (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>122</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>2443404 - Disclosure - Segment Information - Gross Premiums Written by Geographical Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformationGrossPremiumsWrittenByGeographicalAreaDetails</Role>
      <ShortName>Segment Information - Gross Premiums Written by Geographical Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>123</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>2443405 - Disclosure - Segment Information - Summary of Company's Assets by Segment (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/SegmentInformationSummaryOfCompanysAssetsBySegmentDetail</Role>
      <ShortName>Segment Information - Summary of Company's Assets by Segment (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>124</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>2444402 - Disclosure - Unaudited Condensed Quarterly Financial Data (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/UnauditedCondensedQuarterlyFinancialDataDetail</Role>
      <ShortName>Unaudited Condensed Quarterly Financial Data (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/UnauditedCondensedQuarterlyFinancialDataTables</ParentRole>
      <Position>125</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>2445401 - Disclosure - Schedule I - Summary of Investments Other Than Investments in Related Parties (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleISummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesDetail</Role>
      <ShortName>Schedule I - Summary of Investments Other Than Investments in Related Parties (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/ScheduleISummaryOfInvestmentsOtherThanInvestmentsInRelatedParties</ParentRole>
      <Position>126</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>2449401 - Disclosure - Schedule II - Condensed Balance Sheets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiCondensedBalanceSheetsDetail</Role>
      <ShortName>Schedule II - Condensed Balance Sheets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>127</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>2449402 - Disclosure - Schedule II - Condensed Statements of Earnings (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiCondensedStatementsOfEarningsDetail</Role>
      <ShortName>Schedule II - Condensed Statements of Earnings (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>128</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R129.htm</HtmlFileName>
      <LongName>2449403 - Disclosure - Schedule II - Comprehensive Income (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiComprehensiveIncomeDetail</Role>
      <ShortName>Schedule II - Comprehensive Income (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>129</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R130.htm</HtmlFileName>
      <LongName>2449404 - Disclosure - Schedule II - Condensed Statements of Cash Flows (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiCondensedStatementsOfCashFlowsDetail</Role>
      <ShortName>Schedule II - Condensed Statements of Cash Flows (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>130</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R131.htm</HtmlFileName>
      <LongName>2449405 - Disclosure - Schedule II - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiNarrativeDetails</Role>
      <ShortName>Schedule II - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>131</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>2450401 - Disclosure - Schedule III - Supplementary Insurance Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIiiSupplementaryInsuranceInformationDetail</Role>
      <ShortName>Schedule III - Supplementary Insurance Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/ScheduleIiiSupplementaryInsuranceInformation</ParentRole>
      <Position>132</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>2451401 - Disclosure - Schedule IV - Reinsurance (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleIvReinsuranceDetail</Role>
      <ShortName>Schedule IV - Reinsurance (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/ScheduleIvReinsurance</ParentRole>
      <Position>133</Position>
    </Report>
    <Report instance="esgr-20151231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>2452401 - Disclosure - Schedule VI - Supplementary Information Concerning Property/Casualty Insurance Operations (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.enstargroup.com/role/ScheduleViSupplementaryInformationConcerningPropertyCasualtyInsuranceOperationsDetail</Role>
      <ShortName>Schedule VI - Supplementary Information Concerning Property/Casualty Insurance Operations (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.enstargroup.com/role/ScheduleViSupplementaryInformationConcerningPropertyCasualtyInsuranceOperations</ParentRole>
      <Position>134</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>esgr-20151231.xml</File>
    <File>esgr-20151231.xsd</File>
    <File>esgr-20151231_cal.xml</File>
    <File>esgr-20151231_def.xml</File>
    <File>esgr-20151231_lab.xml</File>
    <File>esgr-20151231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies/>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
