<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.23.4</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>299</ContextCount>
  <ElementCount>98</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>196</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000001 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>020000 - Document - Risk/Return Summary {Unlabeled} - American Funds Global Growth Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsGlobalGrowthPortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Global Growth Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>020007 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Global Growth Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsGlobalGrowthPortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Global Growth Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>020008 - Document - Risk/Return Summary {Unlabeled} - American Funds Growth Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsGrowthPortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Growth Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>020015 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Growth Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsGrowthPortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Growth Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>020016 - Document - Risk/Return Summary {Unlabeled} - American Funds Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>020023 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>020024 - Document - Risk/Return Summary {Unlabeled} - American Funds Moderate Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsModerateGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Moderate Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>020031 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Moderate Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsModerateGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Moderate Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>020032 - Document - Risk/Return Summary {Unlabeled} - American Funds Conservative Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsConservativeGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Conservative Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>020039 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Conservative Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsConservativeGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Conservative Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>020040 - Document - Risk/Return Summary {Unlabeled} - American Funds Tax-Aware Conservative Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsTaxAwareConservativeGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Tax-Aware Conservative Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>020047 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Tax-Aware Conservative Growth and Income Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsTaxAwareConservativeGrowthandIncomePortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Tax-Aware Conservative Growth and Income Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>020048 - Document - Risk/Return Summary {Unlabeled} - American Funds Preservation Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsPreservationPortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Preservation Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>020055 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Preservation Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsPreservationPortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Preservation Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>020056 - Document - Risk/Return Summary {Unlabeled} - American Funds Tax-Exempt Preservation Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DocumentRiskReturnSummaryUnlabeledAmericanFundsTaxExemptPreservationPortfolio</Role>
      <ShortName>Risk/Return Summary- American Funds Tax-Exempt Preservation Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ck0001537151-20231215.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>020063 - Disclosure - Risk/Return Detail Data {Elements} - American Funds Tax-Exempt Preservation Portfolio</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.american.com/20231215/role/DisclosureRiskReturnDetailDataElementsAmericanFundsTaxExemptPreservationPortfolio</Role>
      <ShortName>Risk/Return Detail Data- American Funds Tax-Exempt Preservation Portfolio</ShortName>
      <MenuCategory>Risk/Return</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="485BPOS" isN1a="true" isRR="true" isRRorOEF="true" original="ck0001537151-20231215.htm">ck0001537151-20231215.htm</File>
    <File>ck0001537151-20231215.xsd</File>
    <File>ck0001537151-20231215_cal.xml</File>
    <File>ck0001537151-20231215_def.xml</File>
    <File>ck0001537151-20231215_lab.xml</File>
    <File>ck0001537151-20231215_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>img_001.jpg</File>
    <File>img_002.jpg</File>
    <File>img_003.jpg</File>
    <File>img_004.jpg</File>
    <File>img_005.jpg</File>
    <File>img_006.jpg</File>
    <File>img_007.jpg</File>
    <File>img_008.jpg</File>
    <File>img_009.jpg</File>
    <File>img_010.jpg</File>
    <File>img_011.jpg</File>
    <File>x1_c107441x16x1.jpg</File>
    <File>x1_c107441x17x1.jpg</File>
    <File>x1_c107441x18x1.jpg</File>
    <File>x1_c107441x20x1.jpg</File>
    <File>x1_c107441x22x1.jpg</File>
    <File>x1_c107441x24x1.jpg</File>
    <File>x1_c107441x26x1.jpg</File>
    <File>x1_c107441x27x1.jpg</File>
    <File>BarChart1.png</File>
    <File>BarChart2.png</File>
    <File>BarChart3.png</File>
    <File>BarChart4.png</File>
    <File>BarChart5.png</File>
    <File>BarChart6.png</File>
    <File>BarChart7.png</File>
    <File>BarChart8.png</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="158">http://xbrl.sec.gov/dei/2023</BaseTaxonomy>
    <BaseTaxonomy items="3452">http://xbrl.sec.gov/rr/2023</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
