<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Version>2.4.0.8</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>146</ContextCount>
  <ElementCount>329</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>69</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>15</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/CondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001501 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/CondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002000 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/CondensedConsolidatedStatementsOfOperationsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Operations (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1004000 - Statement - Condensed Consolidated Statement of Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/CondensedConsolidatedStatementOfStockholdersEquity</Role>
      <ShortName>Condensed Consolidated Statement of Stockholders' Equity</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1005000 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/CondensedConsolidatedStatementsOfCashFlowsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Organization and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OrganizationAndBasisOfPresentation</Role>
      <ShortName>Organization and Basis of Presentation</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2107100 - Disclosure - Acquisitions and Divestitures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AcquisitionsAndDivestitures</Role>
      <ShortName>Acquisitions and Divestitures</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - Major Customers and Concentrations of Credit Risk</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/MajorCustomersAndConcentrationsOfCreditRisk</Role>
      <ShortName>Major Customers and Concentrations of Credit Risk</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - Oil and Gas Properties and Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipment</Role>
      <ShortName>Oil and Gas Properties and Equipment</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2114100 - Disclosure - Derivative Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstruments</Role>
      <ShortName>Derivative Instruments</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/Debt</Role>
      <ShortName>Debt</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2118100 - Disclosure - Asset Retirement Obligations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AssetRetirementObligations</Role>
      <ShortName>Asset Retirement Obligations</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2119100 - Disclosure - Stock-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensation</Role>
      <ShortName>Stock-Based Compensation</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2121100 - Disclosure - Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockholdersEquity</Role>
      <ShortName>Stockholders' Equity</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2122100 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2123100 - Disclosure - Alaska Production Credits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AlaskaProductionCredits</Role>
      <ShortName>Alaska Production Credits</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2124100 - Disclosure - Litigation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/Litigation</Role>
      <ShortName>Litigation</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2126100 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2202201 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Acquisitions and Divestitures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AcquisitionsAndDivestituresTables</Role>
      <ShortName>Acquisitions and Divestitures (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2313301 - Disclosure - Oil and Gas Properties and Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipmentTables</Role>
      <ShortName>Oil and Gas Properties and Equipment (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2314301 - Disclosure - Derivative Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstrumentsTables</Role>
      <ShortName>Derivative Instruments (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2315301 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2316301 - Disclosure - Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtTables</Role>
      <ShortName>Debt (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2318301 - Disclosure - Asset Retirement Obligations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AssetRetirementObligationsTables</Role>
      <ShortName>Asset Retirement Obligations (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2319301 - Disclosure - Stock-Based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationTables</Role>
      <ShortName>Stock-Based Compensation (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2323301 - Disclosure - Alaska Production Credits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AlaskaProductionCreditsTables</Role>
      <ShortName>Alaska Production Credits (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SummaryOfSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Acquisitions and Divestitures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AcquisitionsAndDivestituresDetails</Role>
      <ShortName>Acquisitions and Divestitures (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2407403 - Disclosure - Acquisitions and Divestitures (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AcquisitionsAndDivestituresDetailsTextual</Role>
      <ShortName>Acquisitions and Divestitures (Details Textual)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2407404 - Disclosure - Acquisitions and Divestitures (Details Textual 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AcquisitionsAndDivestituresDetailsTextual1</Role>
      <ShortName>Acquisitions and Divestitures (Details Textual 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2408401 - Disclosure - Major Customers and Concentrations of Credit Risk (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/MajorCustomersAndConcentrationsOfCreditRiskDetails</Role>
      <ShortName>Major Customers and Concentrations of Credit Risk (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2410401 - Disclosure - Related Party Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/RelatedPartyTransactionsDetails</Role>
      <ShortName>Related Party Transactions (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2413402 - Disclosure - Oil and Gas Properties and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipmentDetails</Role>
      <ShortName>Oil and Gas Properties and Equipment (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2413403 - Disclosure - Oil and Gas Properties and Equipment (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipmentDetails1</Role>
      <ShortName>Oil and Gas Properties and Equipment (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2413404 - Disclosure - Oil and Gas Properties and Equipment (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipmentDetails2</Role>
      <ShortName>Oil and Gas Properties and Equipment (Details 2)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2413405 - Disclosure - Oil and Gas Properties and Equipment (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/OilAndGasPropertiesAndEquipmentDetailsTextual</Role>
      <ShortName>Oil and Gas Properties and Equipment (Details Textual)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2414402 - Disclosure - Derivative Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstrumentsDetails</Role>
      <ShortName>Derivative Instruments (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2414403 - Disclosure - Derivative Instruments (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstrumentsDetails1</Role>
      <ShortName>Derivative Instruments (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2414404 - Disclosure - Derivative Instruments (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstrumentsDetails2</Role>
      <ShortName>Derivative Instruments (Details 2)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2414405 - Disclosure - Derivative Instruments (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DerivativeInstrumentsDetails3</Role>
      <ShortName>Derivative Instruments (Details 3)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2415402 - Disclosure - Fair Value Measurements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/FairValueMeasurementsDetails</Role>
      <ShortName>Fair Value Measurements (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2416402 - Disclosure - Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtDetails</Role>
      <ShortName>Debt (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2416403 - Disclosure - Debt (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtDetails1</Role>
      <ShortName>Debt (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2416404 - Disclosure - Debt (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtDetails2</Role>
      <ShortName>Debt (Details 2)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2416405 - Disclosure - Debt (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtDetailsTextual</Role>
      <ShortName>Debt (Details Textual)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2416406 - Disclosure - Debt (Details Textual 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/DebtDetailsTextual1</Role>
      <ShortName>Debt (Details Textual 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2418402 - Disclosure - Asset Retirement Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AssetRetirementObligationsDetails</Role>
      <ShortName>Asset Retirement Obligations (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2419402 - Disclosure - Stock-Based Compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationDetails</Role>
      <ShortName>Stock-Based Compensation (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2419403 - Disclosure - Stock-Based Compensation (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationDetails1</Role>
      <ShortName>Stock-Based Compensation (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2419404 - Disclosure - Stock-Based Compensation (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationDetails2</Role>
      <ShortName>Stock-Based Compensation (Details 2)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2419405 - Disclosure - Stock-Based Compensation (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationDetails3</Role>
      <ShortName>Stock-Based Compensation (Details 3)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2419406 - Disclosure - Stock-Based Compensation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockBasedCompensationDetailsTextual</Role>
      <ShortName>Stock-Based Compensation (Details Textual)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2421401 - Disclosure - Stockholders' Equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockholdersEquityDetails</Role>
      <ShortName>Stockholders' Equity (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2421402 - Disclosure - Stockholders' Equity (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockholdersEquityDetails1</Role>
      <ShortName>Stockholders' Equity (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2421403 - Disclosure - Stockholders' Equity (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/StockholdersEquityDetails2</Role>
      <ShortName>Stockholders' Equity (Details 2)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2422401 - Disclosure - Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/IncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2423402 - Disclosure - Alaska Production Credits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AlaskaProductionCreditsDetails</Role>
      <ShortName>Alaska Production Credits (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2423403 - Disclosure - Alaska Production Credits (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/AlaskaProductionCreditsDetailsTextual</Role>
      <ShortName>Alaska Production Credits (Details Textual)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2424401 - Disclosure - Litigation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/LitigationDetails</Role>
      <ShortName>Litigation (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2426401 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2426402 - Disclosure - Subsequent Events (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.millerenergyresources.com/role/SubsequentEventsDetails1</Role>
      <ShortName>Subsequent Events (Details 1)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Info">Element mill_BusinessAcquisitionPercentageofWorkingInterestsAcquired had a mix of decimals attribute values: 0 3.</Log>
    <Log type="Info">'Monetary' elements on report '1001501 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2408401 - Disclosure - Major Customers and Concentrations of Credit Risk (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2416402 - Disclosure - Debt (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2426401 - Disclosure - Subsequent Events (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 1001000 - Statement - Condensed Consolidated Balance Sheets</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jul. 31, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Apr. 30, 2013'</Log>
    <Log type="Info">Process Flow-Through: 1001501 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 1002000 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</Log>
    <Log type="Info">Process Flow-Through: 1005000 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</Log>
  </Logs>
  <InputFiles>
    <File>mill-20140731.xml</File>
    <File>mill-20140731.xsd</File>
    <File>mill-20140731_cal.xml</File>
    <File>mill-20140731_def.xml</File>
    <File>mill-20140731_lab.xml</File>
    <File>mill-20140731_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
