<?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>2.4.1.9</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>92</ContextCount>
  <ElementCount>173</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>39</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>7</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/StatementBalanceSheets</Role>
      <ShortName>Balance Sheets</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100020 - Statement - Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/StatementBalanceSheetsParenthetical</Role>
      <ShortName>Balance Sheets (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100030 - Statement - Statements of Operations and Other Comprehensive Income (Loss) (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/StatementStatementsOfOperationsAndOtherComprehensiveIncomeLossUnaudited</Role>
      <ShortName>Statements of Operations and Other Comprehensive Income (Loss) (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100040 - Statement - Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/StatementStatementsOfCashFlowsUnaudited</Role>
      <ShortName>Statements of Cash Flows (Unaudited)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100050 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100060 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureInvestments</Role>
      <ShortName>Investments</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>100070 - Disclosure - Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquity</Role>
      <ShortName>Stockholders' Equity</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>100080 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>100090 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>100100 - Disclosure - Revenue and Vendor Concentrations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureRevenueAndVendorConcentrations</Role>
      <ShortName>Revenue and Vendor Concentrations</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>100110 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies (Policies)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>100120 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesTables</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>100130 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureInvestmentsTables</Role>
      <ShortName>Investments (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>100140 - Disclosure - Stockholders' Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityTables</Role>
      <ShortName>Stockholders' Equity (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>100150 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>100160 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies - Potentially Dilutive Common Shares (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesPotentiallyDilutiveCommonSharesDetail</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies - Potentially Dilutive Common Shares (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>100170 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies - Calculation of Basic and Diluted Net Income (Loss) Per Share (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesCalculationOfBasicAndDilutedNetIncomeLossPerShareDetail</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies - Calculation of Basic and Diluted Net Income (Loss) Per Share (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>100180 - Disclosure - Nature of Operations and Summary of Significant Accounting Policies - Summary of Accounts Receivable (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureNatureOfOperationsAndSummaryOfSignificantAccountingPoliciesSummaryOfAccountsReceivableDetail</Role>
      <ShortName>Nature of Operations and Summary of Significant Accounting Policies - Summary of Accounts Receivable (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>100190 - Disclosure - Investments - Summary of Investments by Type of Security (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureInvestmentsSummaryOfInvestmentsByTypeOfSecurityDetail</Role>
      <ShortName>Investments - Summary of Investments by Type of Security (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>100200 - Disclosure - Investments - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureInvestmentsAdditionalInformationDetail</Role>
      <ShortName>Investments - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>100210 - Disclosure - Investments - Summary of Fair Value of Investments Measured on Recurring Basis (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureInvestmentsSummaryOfFairValueOfInvestmentsMeasuredOnRecurringBasisDetail</Role>
      <ShortName>Investments - Summary of Fair Value of Investments Measured on Recurring Basis (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>100220 - Disclosure - Stockholders' Equity - Stock-Based Compensation Expense Related to Stock Options and RSUs (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityStockBasedCompensationExpenseRelatedToStockOptionsAndRsusDetail</Role>
      <ShortName>Stockholders' Equity - Stock-Based Compensation Expense Related to Stock Options and RSUs (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>100230 - Disclosure - Stockholders' Equity - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityAdditionalInformationDetail</Role>
      <ShortName>Stockholders' Equity - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>100240 - Disclosure - Stockholders' Equity - Fair Value Calculations for Stock-Based Compensation Awards (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityFairValueCalculationsForStockBasedCompensationAwardsDetail</Role>
      <ShortName>Stockholders' Equity - Fair Value Calculations for Stock-Based Compensation Awards (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>100250 - Disclosure - Stockholders' Equity - Stock Option Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityStockOptionActivityDetail</Role>
      <ShortName>Stockholders' Equity - Stock Option Activity (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>100260 - Disclosure - Stockholders' Equity - RSU Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureStockholdersEquityRSUActivityDetail</Role>
      <ShortName>Stockholders' Equity - RSU Activity (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>100270 - Disclosure - Income Taxes - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetail</Role>
      <ShortName>Income Taxes - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>100280 - Disclosure - Commitments and Contingencies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetail</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Detail)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>100290 - Disclosure - Revenue and Vendor Concentrations - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.miteksystems.com/20150331/taxonomy/role/DisclosureRevenueAndVendorConcentrationsAdditionalInformationDetail</Role>
      <ShortName>Revenue and Vendor Concentrations - Additional Information (Detail)</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">Columns in Cash Flows statement 'Statements of Cash Flows (Unaudited) (USD $)' have maximum duration 181 days and at least 27 values. Shorter duration columns must have at least one fourth (6) as many values. Column '1/1/2014 - 3/31/2014' is shorter (89 days) and has only 3 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Statements of Cash Flows (Unaudited) (USD $)' have maximum duration 181 days and at least 27 values. Shorter duration columns must have at least one fourth (6) as many values. Column '1/1/2015 - 3/31/2015' is shorter (89 days) and has only 3 values, so it is being removed.</Log>
    <Log type="Info">Process Flow-Through: 100010 - Statement - Balance Sheets</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Mar. 31, 2014'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Sep. 30, 2013'</Log>
    <Log type="Info">Process Flow-Through: 100020 - Statement - Balance Sheets (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 100030 - Statement - Statements of Operations and Other Comprehensive Income (Loss) (Unaudited)</Log>
    <Log type="Info">Process Flow-Through: 100040 - Statement - Statements of Cash Flows (Unaudited)</Log>
  </Logs>
  <InputFiles>
    <File>mitk-20150331.xml</File>
    <File>mitk-20150331.xsd</File>
    <File>mitk-20150331_cal.xml</File>
    <File>mitk-20150331_def.xml</File>
    <File>mitk-20150331_lab.xml</File>
    <File>mitk-20150331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
