<?xml version="1.0" encoding="utf-8"?>
<FilingSummary xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <Version>2.4.0.6</Version>
  <ProcessingTime />
  <ReportFormat>Html</ReportFormat>
  <ContextCount>225</ContextCount>
  <ElementCount>423</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>55</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>8</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.mantech.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 - Consolidated Balance Sheet</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ConsolidatedBalanceSheet</Role>
      <ShortName>Consolidated Balance Sheet</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1001500 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002000 - Statement - Consolidated Statements Of Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ConsolidatedStatementsOfIncome</Role>
      <ShortName>Consolidated Statements Of Income</ShortName>
    </Report>
    <Report>
      <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.mantech.com/role/ConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>Consolidated Statements Of Comprehensive Income</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1004000 - Statement - Consolidated Statements of Changes in Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ConsolidatedStatementsOfChangesInStockholdersEquity</Role>
      <ShortName>Consolidated Statements of Changes in Stockholders' Equity</ShortName>
    </Report>
    <Report>
      <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.mantech.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Description of the Business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/DescriptionOfBusiness</Role>
      <ShortName>Description of the Business</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/Acquisitions</Role>
      <ShortName>Acquisitions</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - Earnings Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/EarningsPerShare</Role>
      <ShortName>Earnings Per Share</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Revenues and Receivables</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/RevenuesAndReceivables</Role>
      <ShortName>Revenues and Receivables</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2107100 - Disclosure - Property And Equipment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/PropertyAndEquipment</Role>
      <ShortName>Property And Equipment</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - Goodwill And Other Intangibles</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangibles</Role>
      <ShortName>Goodwill And Other Intangibles</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - Long-Term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebt</Role>
      <ShortName>Long-Term Debt</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Commitments And Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments And Contingencies</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2111100 - Disclosure - Stockholders Equity and Stock Options</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptions</Role>
      <ShortName>Stockholders Equity and Stock Options</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2112100 - Disclosure - Retirement Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/RetirementPlans</Role>
      <ShortName>Retirement Plans</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2114100 - Disclosure - Business Segment And Geographic Area Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformation</Role>
      <ShortName>Business Segment And Geographic Area Information</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - Sale Of Investment</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SaleOfInvestment</Role>
      <ShortName>Sale Of Investment</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Quarterly Financial Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/QuarterlyFinancialData</Role>
      <ShortName>Quarterly Financial Data</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2117100 - Disclosure - Subsequent Event</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SubsequentEvent</Role>
      <ShortName>Subsequent Event</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2118100 - Schedule - Schedule II</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ScheduleIi</Role>
      <ShortName>Schedule II</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2202201 - Disclosure - Summary of Significnat Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SummaryOfSignificnatAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significnat Accounting Policies (Policies)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2304301 - Disclosure - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/AcquisitionsTables</Role>
      <ShortName>Acquisitions (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - Earnings Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/EarningsPerShareTables</Role>
      <ShortName>Earnings Per Share (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Revenues and Receivables (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/RevenuesAndReceivablesTables</Role>
      <ShortName>Revenues and Receivables (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Property And Equipment (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/PropertyAndEquipmentTables</Role>
      <ShortName>Property And Equipment (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2308301 - Disclosure - Goodwill And Other Intangibles (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangiblesTables</Role>
      <ShortName>Goodwill And Other Intangibles (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2309301 - Disclosure - Long-Term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebtTables</Role>
      <ShortName>Long-Term Debt (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2310301 - Disclosure - Commitments And Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/CommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments And Contingencies (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2311301 - Disclosure - Stockholders Equity and Stock Options (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsTables</Role>
      <ShortName>Stockholders Equity and Stock Options (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2313301 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2314301 - Disclosure - Business Segment And Geographic Area Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationTables</Role>
      <ShortName>Business Segment And Geographic Area Information (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2316301 - Disclosure - Quarterly Financial Data (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/QuarterlyFinancialDataTables</Role>
      <ShortName>Quarterly Financial Data (Tables)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SummaryOfSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2404402 - Disclosure - Acquisitions (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/AcquisitionsNarrativeDetails</Role>
      <ShortName>Acquisitions (Narrative) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2404403 - Disclosure - Acquisitions (Purchase Price Allocation) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/AcquisitionsPurchasePriceAllocationDetails</Role>
      <ShortName>Acquisitions (Purchase Price Allocation) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2404404 - Disclosure - Acquisitions (Pro Forma Financial Information) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/AcquisitionsProFormaFinancialInformationDetails</Role>
      <ShortName>Acquisitions (Pro Forma Financial Information) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - Earnings Per Share - Dividends (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/EarningsPerShareDividendsDetails</Role>
      <ShortName>Earnings Per Share - Dividends (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2405403 - Disclosure - Earnings Per Share (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/EarningsPerShareNarrativeDetails</Role>
      <ShortName>Earnings Per Share (Narrative) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2405404 - Disclosure - Earnings Per Share (Computation Of Weighted Average Number Of Common Shares) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/EarningsPerShareComputationOfWeightedAverageNumberOfCommonSharesDetails</Role>
      <ShortName>Earnings Per Share (Computation Of Weighted Average Number Of Common Shares) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Reveneus and Receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ReveneusAndReceivablesDetails</Role>
      <ShortName>Reveneus and Receivables (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2406403 - Disclosure - Revenues and Receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/RevenuesAndReceivablesDetails</Role>
      <ShortName>Revenues and Receivables (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Property And Equipment (Major Classes Of Property And Equipment) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/PropertyAndEquipmentMajorClassesOfPropertyAndEquipmentDetails</Role>
      <ShortName>Property And Equipment (Major Classes Of Property And Equipment) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2408402 - Disclosure - Goodwill And Other Intangibles (Changes In Carrying Amounts Of Goodwill) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangiblesChangesInCarryingAmountsOfGoodwillDetails</Role>
      <ShortName>Goodwill And Other Intangibles (Changes In Carrying Amounts Of Goodwill) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - Goodwill And Other Intangibles (Summary Of Intangible Assets) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangiblesSummaryOfIntangibleAssetsDetails</Role>
      <ShortName>Goodwill And Other Intangibles (Summary Of Intangible Assets) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2408404 - Disclosure - Goodwill And Other Intangibles (Schedule Of Future Period Amortization Expense) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangiblesScheduleOfFuturePeriodAmortizationExpenseDetails</Role>
      <ShortName>Goodwill And Other Intangibles (Schedule Of Future Period Amortization Expense) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2408405 - Disclosure - Goodwill And Other Intangibles Schedule of Future Amortization Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/GoodwillAndOtherIntangiblesScheduleOfFutureAmortizationExpenseDetails</Role>
      <ShortName>Goodwill And Other Intangibles Schedule of Future Amortization Expense (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2409402 - Disclosure - Long-Term Debt (Components Of Long-term Debt) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebtComponentsOfLongTermDebtDetails</Role>
      <ShortName>Long-Term Debt (Components Of Long-term Debt) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2409403 - Disclosure - Long-Term Debt Activity Under Revolving Credit Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebtActivityUnderRevolvingCreditFacilityDetails</Role>
      <ShortName>Long-Term Debt Activity Under Revolving Credit Facility (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2409404 - Disclosure - Long-Term Debt Schedule of Revolving Credit Facility (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebtScheduleOfRevolvingCreditFacilityDetails</Role>
      <ShortName>Long-Term Debt Schedule of Revolving Credit Facility (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2409405 - Disclosure - Long-Term Debt Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/LongTermDebtNarrativeDetails</Role>
      <ShortName>Long-Term Debt Narrative (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2410402 - Disclosure - Commitments And Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/CommitmentsAndContingenciesDetails</Role>
      <ShortName>Commitments And Contingencies (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2411402 - Disclosure - Stockholders Equity and Stock Options (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsNarrativeDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Narrative) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2411403 - Disclosure - Stockholders Equity and Stock Options (Schedule Of Weighted-Average Assumptions Used In Calculation Of Fair Value) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsScheduleOfWeightedAverageAssumptionsUsedInCalculationOfFairValueDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Schedule Of Weighted-Average Assumptions Used In Calculation Of Fair Value) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2411404 - Disclosure - Stockholders Equity and Stock Options (Stock Option Activity And Options Outstanding) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsStockOptionActivityAndOptionsOutstandingDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Stock Option Activity And Options Outstanding) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2411405 - Disclosure - Stockholders Equity and Stock Options (Summary Of Non-Vested Stock Options) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsSummaryOfNonVestedStockOptionsDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Summary Of Non-Vested Stock Options) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2411406 - Disclosure - Stockholders Equity and Stock Options (Stock Options Exercisable And Expected To Vest) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsStockOptionsExercisableAndExpectedToVestDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Stock Options Exercisable And Expected To Vest) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2411407 - Disclosure - Stockholders Equity and Stock Options (Summary Of Restricted Stock Activity) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/StockholdersEquityAndStockOptionsSummaryOfRestrictedStockActivityDetails</Role>
      <ShortName>Stockholders Equity and Stock Options (Summary Of Restricted Stock Activity) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2412401 - Disclosure - Retirement Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/RetirementPlansDetails</Role>
      <ShortName>Retirement Plans (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2413402 - Disclosure - Income Taxes Domestic and Foreign Components of Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesDomesticAndForeignComponentsOfIncomeDetails</Role>
      <ShortName>Income Taxes Domestic and Foreign Components of Income (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2413403 - Disclosure - Income Taxes Provision for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesProvisionForIncomeTaxesDetails</Role>
      <ShortName>Income Taxes Provision for Income Taxes (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2413404 - Disclosure - Income Taxes Effective Income Tax Rate Reconciliation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesEffectiveIncomeTaxRateReconciliationDetails</Role>
      <ShortName>Income Taxes Effective Income Tax Rate Reconciliation (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2413405 - Disclosure - Income Taxes Schedule of Deferred Tax Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails</Role>
      <ShortName>Income Taxes Schedule of Deferred Tax Assets and Liabilities (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2413406 - Disclosure - Income Taxes Summary of Income Tax Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesSummaryOfIncomeTaxContingenciesDetails</Role>
      <ShortName>Income Taxes Summary of Income Tax Contingencies (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2413407 - Disclosure - Income Taxes Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/IncomeTaxesNarrativeDetails</Role>
      <ShortName>Income Taxes Narrative (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2414402 - Disclosure - Business Segment And Geographic Area Information (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationNarrativeDetails</Role>
      <ShortName>Business Segment And Geographic Area Information (Narrative) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2414403 - Disclosure - Business Segment And Geographic Area Information (Schedule Of Revenue By Geographic Customer And Related Percentage Of Total Revenue) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationScheduleOfRevenueByGeographicCustomerAndRelatedPercentageOfTotalRevenueDetails</Role>
      <ShortName>Business Segment And Geographic Area Information (Schedule Of Revenue By Geographic Customer And Related Percentage Of Total Revenue) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2414404 - Disclosure - Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Revenue From External Customers) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationContractsExceeding10OfRevenueFromExternalCustomersDetails</Role>
      <ShortName>Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Revenue From External Customers) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2414405 - Disclosure - Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Other Income From External Customers) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationContractsExceeding10OfOtherIncomeFromExternalCustomersDetails</Role>
      <ShortName>Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Other Income From External Customers) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2414406 - Disclosure - Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Receivables) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/BusinessSegmentAndGeographicAreaInformationContractsExceeding10OfReceivablesDetails</Role>
      <ShortName>Business Segment And Geographic Area Information (Contracts Exceeding 10% Of Receivables) (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2415401 - Disclosure - Sale Of Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SaleOfInvestmentDetails</Role>
      <ShortName>Sale Of Investment (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2416402 - Disclosure - Quarterly Financial Data (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/QuarterlyFinancialDataDetails</Role>
      <ShortName>Quarterly Financial Data (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2417401 - Disclosure - Subsequent Event (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/SubsequentEventDetails</Role>
      <ShortName>Subsequent Event (Details)</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2418401 - Schedule - Schedule II (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.mantech.com/role/ScheduleIiDetails</Role>
      <ShortName>Schedule II (Details)</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 us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed had a mix of decimals attribute values: -5 0.</Log>
    <Log type="Info">Element us-gaap_LineOfCreditFacilityAverageOutstandingAmount had a mix of decimals attribute values: -5 0.</Log>
    <Log type="Info">Element us-gaap_PaymentsOfDebtIssuanceCosts had a mix of decimals attribute values: -3 0.</Log>
    <Log type="Info">'Monetary' elements on report '2402402 - Disclosure - Summary of Significant Accounting Policies (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2404402 - Disclosure - Acquisitions (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Shares' elements on report '2405403 - Disclosure - Earnings Per Share (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2407402 - Disclosure - Property And Equipment (Major Classes Of Property And Equipment) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2410402 - Disclosure - Commitments And Contingencies (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2411402 - Disclosure - Stockholders Equity and Stock Options (Narrative) (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2413407 - Disclosure - Income Taxes Narrative (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '2415401 - Disclosure - Sale Of Investment (Details)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 1001000 - Statement - Consolidated Balance Sheet</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2009'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2008'</Log>
    <Log type="Info">Process Flow-Through: 1001500 - Statement - Consolidated Balance Sheets (Parenthetical)</Log>
    <Log type="Info">Process Flow-Through: 1002000 - Statement - Consolidated Statements Of Income</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2010'</Log>
    <Log type="Info">Process Flow-Through: 1003000 - Statement - Consolidated Statements Of Comprehensive Income</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2011'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2010'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2010'</Log>
    <Log type="Info">Process Flow-Through: 1005000 - Statement - Consolidated Statements of Cash Flows</Log>
  </Logs>
  <InputFiles>
    <File>mant-20111231.xml</File>
    <File>mant-20111231.xsd</File>
    <File>mant-20111231_cal.xml</File>
    <File>mant-20111231_def.xml</File>
    <File>mant-20111231_lab.xml</File>
    <File>mant-20111231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles />
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
