<?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>92</ContextCount>
  <ElementCount>77</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>76</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentDocumentandEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>000011 - Document - Risk/Return Summary {Unlabeled} - Money Market Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledMoneyMarketFund</Role>
      <ShortName>Risk/Return Summary  - Money Market Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>000019 - Disclosure - Risk/Return Detail Data {Elements} - Money Market Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsMoneyMarketFund</Role>
      <ShortName>Risk/Return Detail Data  - Money Market Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>000021 - Document - Risk/Return Summary {Unlabeled} - Limited Maturity Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledLimitedMaturityBondFund</Role>
      <ShortName>Risk/Return Summary  - Limited Maturity Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>000029 - Disclosure - Risk/Return Detail Data {Elements} - Limited Maturity Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLimitedMaturityBondFund</Role>
      <ShortName>Risk/Return Detail Data  - Limited Maturity Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>000031 - Document - Risk/Return Summary {Unlabeled} - Quality Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledQualityBondFund</Role>
      <ShortName>Risk/Return Summary  - Quality Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>000039 - Disclosure - Risk/Return Detail Data {Elements} - Quality Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsQualityBondFund</Role>
      <ShortName>Risk/Return Detail Data  - Quality Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>000041 - Document - Risk/Return Summary {Unlabeled} - High Yield Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledHighYieldBondFund</Role>
      <ShortName>Risk/Return Summary  - High Yield Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>000049 - Disclosure - Risk/Return Detail Data {Elements} - High Yield Bond Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsHighYieldBondFund</Role>
      <ShortName>Risk/Return Detail Data  - High Yield Bond Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>000051 - Document - Risk/Return Summary {Unlabeled} - Flexibly Managed Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledFlexiblyManagedFund</Role>
      <ShortName>Risk/Return Summary  - Flexibly Managed Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>000059 - Disclosure - Risk/Return Detail Data {Elements} - Flexibly Managed Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsFlexiblyManagedFund</Role>
      <ShortName>Risk/Return Detail Data  - Flexibly Managed Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>000061 - Document - Risk/Return Summary {Unlabeled} - Balanced Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledBalancedFund</Role>
      <ShortName>Risk/Return Summary  - Balanced Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>000069 - Disclosure - Risk/Return Detail Data {Elements} - Balanced Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsBalancedFund</Role>
      <ShortName>Risk/Return Detail Data  - Balanced Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>000071 - Document - Risk/Return Summary {Unlabeled} - Large Growth Stock Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledLargeGrowthStockFund</Role>
      <ShortName>Risk/Return Summary  - Large Growth Stock Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>000079 - Disclosure - Risk/Return Detail Data {Elements} - Large Growth Stock Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLargeGrowthStockFund</Role>
      <ShortName>Risk/Return Detail Data  - Large Growth Stock Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>000081 - Document - Risk/Return Summary {Unlabeled} - Large Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledLargeCapGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Large Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>000089 - Disclosure - Risk/Return Detail Data {Elements} - Large Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLargeCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Large Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>000091 - Document - Risk/Return Summary {Unlabeled} - Large Core Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledLargeCoreGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Large Core Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>000099 - Disclosure - Risk/Return Detail Data {Elements} - Large Core Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLargeCoreGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Large Core Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>000101 - Document - Risk/Return Summary {Unlabeled} - Large Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledLargeCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Large Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>000109 - Disclosure - Risk/Return Detail Data {Elements} - Large Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLargeCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Large Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>000111 - Document - Risk/Return Summary {Unlabeled} - Large Core Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/role/DocumentRiskReturnSummaryUnlabeledLargeCoreValueFund</Role>
      <ShortName>Risk/Return Summary  - Large Core Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>000119 - Disclosure - Risk/Return Detail Data {Elements} - Large Core Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsLargeCoreValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Large Core Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>000121 - Document - Risk/Return Summary {Unlabeled} - Index 500 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledIndex500Fund</Role>
      <ShortName>Risk/Return Summary  - Index 500 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>000129 - Disclosure - Risk/Return Detail Data {Elements} - Index 500 Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsIndex500Fund</Role>
      <ShortName>Risk/Return Detail Data  - Index 500 Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>000131 - Document - Risk/Return Summary {Unlabeled} - Mid Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledMidCapGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Mid Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>000139 - Disclosure - Risk/Return Detail Data {Elements} - Mid Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsMidCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>000141 - Document - Risk/Return Summary {Unlabeled} - Mid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledMidCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Mid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>000149 - Disclosure - Risk/Return Detail Data {Elements} - Mid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsMidCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>000151 - Document - Risk/Return Summary {Unlabeled} - Mid Core Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledMidCoreValueFund</Role>
      <ShortName>Risk/Return Summary  - Mid Core Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>000159 - Disclosure - Risk/Return Detail Data {Elements} - Mid Core Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsMidCoreValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Mid Core Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>000161 - Document - Risk/Return Summary {Unlabeled} - Smid Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledSmidCapGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Smid Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>000169 - Disclosure - Risk/Return Detail Data {Elements} - Smid Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsSmidCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Smid Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>000171 - Document - Risk/Return Summary {Unlabeled} - Smid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledSmidCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Smid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>000179 - Disclosure - Risk/Return Detail Data {Elements} - Smid Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsSmidCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Smid Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>000181 - Document - Risk/Return Summary {Unlabeled} - Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Summary  - Small Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>000189 - Disclosure - Risk/Return Detail Data {Elements} - Small Cap Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsSmallCapGrowthFund</Role>
      <ShortName>Risk/Return Detail Data  - Small Cap Growth Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>000191 - Document - Risk/Return Summary {Unlabeled} - Small Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledSmallCapValueFund</Role>
      <ShortName>Risk/Return Summary  - Small Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>000199 - Disclosure - Risk/Return Detail Data {Elements} - Small Cap Value Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsSmallCapValueFund</Role>
      <ShortName>Risk/Return Detail Data  - Small Cap Value Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>000201 - Document - Risk/Return Summary {Unlabeled} - Small Cap Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledSmallCapIndexFund</Role>
      <ShortName>Risk/Return Summary  - Small Cap Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>000209 - Disclosure - Risk/Return Detail Data {Elements} - Small Cap Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsSmallCapIndexFund</Role>
      <ShortName>Risk/Return Detail Data  - Small Cap Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>000211 - Document - Risk/Return Summary {Unlabeled} - Developed International Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledDevelopedInternationalIndexFund</Role>
      <ShortName>Risk/Return Summary  - Developed International Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>000219 - Disclosure - Risk/Return Detail Data {Elements} - Developed International Index Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsDevelopedInternationalIndexFund</Role>
      <ShortName>Risk/Return Detail Data  - Developed International Index Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>000221 - Document - Risk/Return Summary {Unlabeled} - International Equity Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledInternationalEquityFund</Role>
      <ShortName>Risk/Return Summary  - International Equity Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>000229 - Disclosure - Risk/Return Detail Data {Elements} - International Equity Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsInternationalEquityFund</Role>
      <ShortName>Risk/Return Detail Data  - International Equity Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>000231 - Document - Risk/Return Summary {Unlabeled} - Emerging Markets Equity Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledEmergingMarketsEquityFund</Role>
      <ShortName>Risk/Return Summary  - Emerging Markets Equity Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>000239 - Disclosure - Risk/Return Detail Data {Elements} - Emerging Markets Equity Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsEmergingMarketsEquityFund</Role>
      <ShortName>Risk/Return Detail Data  - Emerging Markets Equity Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R140.htm</HtmlFileName>
      <LongName>000241 - Document - Risk/Return Summary {Unlabeled} - Real Estate Securities Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledRealEstateSecuritiesFund</Role>
      <ShortName>Risk/Return Summary  - Real Estate Securities Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>000249 - Disclosure - Risk/Return Detail Data {Elements} - Real Estate Securities Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsRealEstateSecuritiesFund</Role>
      <ShortName>Risk/Return Detail Data  - Real Estate Securities Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R146.htm</HtmlFileName>
      <LongName>000251 - Document - Risk/Return Summary {Unlabeled} - Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R151.htm</HtmlFileName>
      <LongName>000259 - Disclosure - Risk/Return Detail Data {Elements} - Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R152.htm</HtmlFileName>
      <LongName>000261 - Document - Risk/Return Summary {Unlabeled} - Moderately Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledModeratelyAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Moderately Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R157.htm</HtmlFileName>
      <LongName>000269 - Disclosure - Risk/Return Detail Data {Elements} - Moderately Aggressive Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsModeratelyAggressiveAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Moderately Aggressive Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R158.htm</HtmlFileName>
      <LongName>000271 - Document - Risk/Return Summary {Unlabeled} - Moderate Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledModerateAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Moderate Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R163.htm</HtmlFileName>
      <LongName>000279 - Disclosure - Risk/Return Detail Data {Elements} - Moderate Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsModerateAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Moderate Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R164.htm</HtmlFileName>
      <LongName>000281 - Document - Risk/Return Summary {Unlabeled} - Moderately Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledModeratelyConservativeAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Moderately Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R169.htm</HtmlFileName>
      <LongName>000289 - Disclosure - Risk/Return Detail Data {Elements} - Moderately Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsModeratelyConservativeAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Moderately Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R170.htm</HtmlFileName>
      <LongName>000291 - Document - Risk/Return Summary {Unlabeled} - Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DocumentRiskReturnSummaryUnlabeledConservativeAllocationFund</Role>
      <ShortName>Risk/Return Summary  - Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R175.htm</HtmlFileName>
      <LongName>000299 - Disclosure - Risk/Return Detail Data {Elements} - Conservative Allocation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.pennmutal.com/Role/DisclosureRiskReturnDetailDataElementsConservativeAllocationFund</Role>
      <ShortName>Risk/Return Detail Data  - Conservative Allocation Fund</ShortName>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R176.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>psfi-20120425.xml</File>
    <File>psfi-20120425.xsd</File>
    <File>psfi-20120425_cal.xml</File>
    <File>psfi-20120425_def.xml</File>
    <File>psfi-20120425_lab.xml</File>
    <File>psfi-20120425_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>
    <File>BarChart24.jpg</File>
    <File>BarChart25.jpg</File>
    <File>BarChart26.jpg</File>
    <File>BarChart27.jpg</File>
    <File>BarChart28.jpg</File>
    <File>BarChart29.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies />
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
