<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>25</ContextCount>
  <ElementCount>170</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>17</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001 - Document - Document and Entity Information {Elements}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/DocumentAndEntityInformationElements</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory></MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0002 - Document - Risk/Return Summary {Unlabeled} - Amana Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnSummaryUnlabeledAmanaIncomeFund</Role>
      <ShortName>Risk/Return Summary- Amana Income Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>0008 - Disclosure - Risk/Return Detail Data {Elements} - Amana Income Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnDetailDataElementsAmanaIncomeFund</Role>
      <ShortName>Risk/Return Detail Data- Amana Income Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>0009 - Document - Risk/Return Summary {Unlabeled} - Amana Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnSummaryUnlabeledAmanaGrowthFund</Role>
      <ShortName>Risk/Return Summary- Amana Growth Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>0015 - Disclosure - Risk/Return Detail Data {Elements} - Amana Growth Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnDetailDataElementsAmanaGrowthFund</Role>
      <ShortName>Risk/Return Detail Data- Amana Growth Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>0016 - Document - Risk/Return Summary {Unlabeled} - Amana Developing World Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnSummaryUnlabeledAmanaDevelopingWorldFund</Role>
      <ShortName>Risk/Return Summary- Amana Developing World Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>0022 - Disclosure - Risk/Return Detail Data {Elements} - Amana Developing World Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnDetailDataElementsAmanaDevelopingWorldFund</Role>
      <ShortName>Risk/Return Detail Data- Amana Developing World Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>true</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>0030 - Document - Risk/Return Summary {Unlabeled} - Amana Participation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnSummaryUnlabeledAmanaParticipationFund</Role>
      <ShortName>Risk/Return Summary- Amana Participation Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>0035 - Disclosure - Risk/Return Detail Data {Elements} - Amana Participation Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.amanafunds.com/role/RiskReturnDetailDataElementsAmanaParticipationFund</Role>
      <ShortName>Risk/Return Detail Data- Amana Participation Fund</ShortName>
      <MenuCategory></MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="amft-20200531.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.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>
      <MenuCategory></MenuCategory>
      <Position>10</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Warning">[ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 1 fact(s) appearing in ix:hidden were eligible for transformation: rr:ProspectusDate</Log>
  </Logs>
  <InputFiles>
    <File doctype="485BPOS" original="amft-20200531.htm">amft-20200531.htm</File>
    <File>amft-20200531.xsd</File>
    <File>amft-20200531_cal.xml</File>
    <File>amft-20200531_def.xml</File>
    <File>amft-20200531_lab.xml</File>
    <File>amft-20200531_pre.xml</File>
    <File>ex99i-opinioncounsel.htm</File>
    <File>ex99j1-consentauditor.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>amagx-volatility.gif</File>
    <File>amana-pro.gif</File>
    <File>amanx-volatility.gif</File>
    <File>amdwx-volatility.gif</File>
    <File>amipx-volatility.gif</File>
    <File>sai-cover.gif</File>
    <File>BarChart1.png</File>
    <File>BarChart2.png</File>
    <File>BarChart3.png</File>
    <File>BarChart4.png</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy>http://xbrl.sec.gov/rr/2018-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2020-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
