<?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>90</ContextCount>
  <ElementCount>72</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>61</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000001 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>020000 - Document - Risk/Return Summary {Unlabeled} - Equity Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledEquityIndexFund</Role>
      <ShortName>Risk/Return Summary  - Equity Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>020005 - Disclosure - Risk/Return Detail Data {Elements} - Equity Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsEquityIndexFund</Role>
      <ShortName>Risk/Return Detail Data  - Equity Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>020006 - Document - Risk/Return Summary {Unlabeled} - All America Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledAllAmericaFund</Role>
      <ShortName>Risk/Return Summary  - All America Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>020011 - Disclosure - Risk/Return Detail Data {Elements} - All America Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsAllAmericaFund</Role>
      <ShortName>Risk/Return Detail Data  - All America Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>020012 - Document - Risk/Return Summary {Unlabeled} - Small Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledSmallCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Small Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>020017 - Disclosure - Risk/Return Detail Data {Elements} - Small Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsSmallCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Small Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>020018 - Document - Risk/Return Summary {Unlabeled} - Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Small Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>020023 - Disclosure - Risk/Return Detail Data {Elements} - Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Small Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>020024 - Document - Risk/Return Summary {Unlabeled} - Mid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledMidCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Mid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>020029 - Disclosure - Risk/Return Detail Data {Elements} - Mid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsMidCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>020030 - Document - Risk/Return Summary {Unlabeled} - Mid-Cap Equity Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledMidCapEquityIndexFund</Role>
      <ShortName>Risk/Return Summary  - Mid-Cap Equity Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>020035 - Disclosure - Risk/Return Detail Data {Elements} - Mid-Cap Equity Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsMidCapEquityIndexFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid-Cap Equity Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>020036 - Document - Risk/Return Summary {Unlabeled} - Composite Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledCompositeFund</Role>
      <ShortName>Risk/Return Summary  - Composite Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>020041 - Disclosure - Risk/Return Detail Data {Elements} - Composite Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsCompositeFund</Role>
      <ShortName>Risk/Return Detail Data  - Composite Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>020042 - Document - Risk/Return Summary {Unlabeled} - International Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledInternationalFund</Role>
      <ShortName>Risk/Return Summary  - International Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>020047 - Disclosure - Risk/Return Detail Data {Elements} - International Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsInternationalFund</Role>
      <ShortName>Risk/Return Detail Data  - International Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>020048 - Document - Risk/Return Summary {Unlabeled} - Money Market Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledMoneyMarketFund</Role>
      <ShortName>Risk/Return Summary  - Money Market Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>020053 - Disclosure - Risk/Return Detail Data {Elements} - Money Market Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsMoneyMarketFund</Role>
      <ShortName>Risk/Return Detail Data  - Money Market Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>020054 - Document - Risk/Return Summary {Unlabeled} - Mid-Term Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledMidTermBondFund</Role>
      <ShortName>Risk/Return Summary  - Mid-Term Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>020059 - Disclosure - Risk/Return Detail Data {Elements} - Mid-Term Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsMidTermBondFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid-Term Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>020060 - Document - Risk/Return Summary {Unlabeled} - Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledBondFund</Role>
      <ShortName>Risk/Return Summary  - Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>020065 - Disclosure - Risk/Return Detail Data {Elements} - Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsBondFund</Role>
      <ShortName>Risk/Return Detail Data  - Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>020066 - Document - Risk/Return Summary {Unlabeled} - Retirement Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledRetirementIncomeFund</Role>
      <ShortName>Risk/Return Summary  - Retirement Income Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>020071 - Disclosure - Risk/Return Detail Data {Elements} - Retirement Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsRetirementIncomeFund</Role>
      <ShortName>Risk/Return Detail Data  - Retirement Income Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>020072 - Document - Risk/Return Summary {Unlabeled} - 2010 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2010RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2010 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>020077 - Disclosure - Risk/Return Detail Data {Elements} - 2010 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2010RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2010 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>020078 - Document - Risk/Return Summary {Unlabeled} - 2015 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2015RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2015 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>020083 - Disclosure - Risk/Return Detail Data {Elements} - 2015 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2015RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2015 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>020084 - Document - Risk/Return Summary {Unlabeled} - 2020 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2020RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2020 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>020089 - Disclosure - Risk/Return Detail Data {Elements} - 2020 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2020RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2020 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>020090 - Document - Risk/Return Summary {Unlabeled} - 2025 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2025RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2025 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>020095 - Disclosure - Risk/Return Detail Data {Elements} - 2025 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2025RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2025 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>020096 - Document - Risk/Return Summary {Unlabeled} - 2030 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2030RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2030 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>020101 - Disclosure - Risk/Return Detail Data {Elements} - 2030 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2030RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2030 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>020102 - Document - Risk/Return Summary {Unlabeled} - 2035 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2035RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2035 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>020107 - Disclosure - Risk/Return Detail Data {Elements} - 2035 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2035RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2035 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>020108 - Document - Risk/Return Summary {Unlabeled} - 2040 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2040RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2040 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>020113 - Disclosure - Risk/Return Detail Data {Elements} - 2040 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2040RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2040 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>020114 - Document - Risk/Return Summary {Unlabeled} - 2045 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2045RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2045 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>020119 - Disclosure - Risk/Return Detail Data {Elements} - 2045 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2045RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2045 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>020120 - Document - Risk/Return Summary {Unlabeled} - 2050 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeled2050RetirementFund</Role>
      <ShortName>Risk/Return Summary  - 2050 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>020124 - Disclosure - Risk/Return Detail Data {Elements} - 2050 Retirement Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElements2050RetirementFund</Role>
      <ShortName>Risk/Return Detail Data  - 2050 Retirement Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>020125 - Document - Risk/Return Summary {Unlabeled} - Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledConservativeAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>020130 - Disclosure - Risk/Return Detail Data {Elements} - Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsConservativeAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>020131 - Document - Risk/Return Summary {Unlabeled} - Moderate Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledModerateAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Moderate Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R138.htm</HtmlFileName>
      <LongName>020136 - Disclosure - Risk/Return Detail Data {Elements} - Moderate Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsModerateAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Moderate Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>020137 - Document - Risk/Return Summary {Unlabeled} - Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DocumentRiskReturnSummaryUnlabeledAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R144.htm</HtmlFileName>
      <LongName>020142 - Disclosure - Risk/Return Detail Data {Elements} - Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://dreyfus.com/20130429/role/DisclosureRiskReturnDetailDataElementsAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>040000 - Disclosure - Risk/Return Detail Data {Elements}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/rr/role/RiskReturnDetailData</Role>
      <ShortName>Risk/Return Detail Data</ShortName>
    </Report>
    <Report>
      <IsDefault>true</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs />
  <InputFiles>
    <File>ck0000795259-20130429.xml</File>
    <File>ck0000795259-20130429.xsd</File>
    <File>ck0000795259-20130429_cal.xml</File>
    <File>ck0000795259-20130429_def.xml</File>
    <File>ck0000795259-20130429_lab.xml</File>
    <File>ck0000795259-20130429_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>BarChart1.jpg</File>
    <File>BarChart2.jpg</File>
    <File>BarChart3.jpg</File>
    <File>BarChart4.jpg</File>
    <File>BarChart5.jpg</File>
    <File>BarChart6.jpg</File>
    <File>BarChart7.jpg</File>
    <File>BarChart8.jpg</File>
    <File>BarChart9.jpg</File>
    <File>BarChart10.jpg</File>
    <File>BarChart11.jpg</File>
    <File>BarChart12.jpg</File>
    <File>BarChart13.jpg</File>
    <File>BarChart14.jpg</File>
    <File>BarChart15.jpg</File>
    <File>BarChart16.jpg</File>
    <File>BarChart17.jpg</File>
    <File>BarChart18.jpg</File>
    <File>BarChart19.jpg</File>
    <File>BarChart20.jpg</File>
    <File>BarChart21.jpg</File>
    <File>BarChart22.jpg</File>
    <File>BarChart23.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
