<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.20.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>19</ContextCount>
  <ElementCount>177</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>12</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>2</UnitCount>
  <MyReports>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000000 - Document - Document and Entity Information {Elements}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/DocumentDocumentandEntityInformationElements</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory></MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>000011 - Document - Risk/Return Summary {Unlabeled} - DWS Intermediate Tax-Free Fund (Class ACIS)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/DocumentRiskReturnSummaryUnlabeledDWSIntermediateTax-FreeFundClassACIS</Role>
      <ShortName>Risk/Return Summary- DWS Intermediate Tax-Free Fund (Class ACIS)</ShortName>
      <MenuCategory></MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>000012 - Schedule - Shareholder Fees</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleShareholderFees000012</Role>
      <ShortName>Shareholder Fees</ShortName>
      <MenuCategory></MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>000013 - Schedule - Annual Fund Operating Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAnnualFundOperatingExpenses000013</Role>
      <ShortName>Annual Fund Operating Expenses</ShortName>
      <MenuCategory></MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>000014 - Schedule - Expense Example</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleExpenseExample000014</Role>
      <ShortName>Expense Example</ShortName>
      <MenuCategory></MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>000015 - Schedule - Expense Example, No Redemption</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleExpenseExampleNoRedemption000015</Role>
      <ShortName>Expense Example, No Redemption</ShortName>
      <MenuCategory></MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>000016 - Schedule - Annual Total Returns {Transposed} - DWS Intermediate Tax-Free Fund (Class ACIS) [BarChart]</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAnnualTotalReturnsTransposedBarChart000016</Role>
      <ShortName>Annual Total Returns- DWS Intermediate Tax-Free Fund (Class ACIS) [BarChart]</ShortName>
      <MenuCategory></MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>000017 - Schedule - Average Annual Total Returns {Transposed}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAverageAnnualTotalReturnsTransposed000017</Role>
      <ShortName>Average Annual Total Returns</ShortName>
      <MenuCategory></MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>000019 - Disclosure - Risk/Return Detail Data {Elements} - DWS Intermediate Tax-Free Fund (Class ACIS)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/DisclosureRiskReturnDetailDataElementsDWSIntermediateTax-FreeFundClassACIS</Role>
      <ShortName>Risk/Return Detail Data- DWS Intermediate Tax-Free Fund (Class ACIS)</ShortName>
      <MenuCategory></MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>000021 - Document - Risk/Return Summary {Unlabeled} - DWS Intermediate Tax-Free Fund (Class T)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/DocumentRiskReturnSummaryUnlabeledDWSIntermediateTax-FreeFundClassT</Role>
      <ShortName>Risk/Return Summary- DWS Intermediate Tax-Free Fund (Class T)</ShortName>
      <MenuCategory></MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>000022 - Schedule - Shareholder Fees</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleShareholderFees000022</Role>
      <ShortName>Shareholder Fees</ShortName>
      <MenuCategory></MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>000023 - Schedule - Annual Fund Operating Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAnnualFundOperatingExpenses000023</Role>
      <ShortName>Annual Fund Operating Expenses</ShortName>
      <MenuCategory></MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>000024 - Schedule - Expense Example {Transposed}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleExpenseExampleTransposed000024</Role>
      <ShortName>Expense Example</ShortName>
      <MenuCategory></MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>000026 - Schedule - Annual Total Returns {Transposed} - DWS Intermediate Tax-Free Fund (Class T) [BarChart]</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAnnualTotalReturnsTransposedBarChart000026</Role>
      <ShortName>Annual Total Returns- DWS Intermediate Tax-Free Fund (Class T) [BarChart]</ShortName>
      <MenuCategory></MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>000027 - Schedule - Average Annual Total Returns {Transposed}</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/ScheduleAverageAnnualTotalReturnsTransposed000027</Role>
      <ShortName>Average Annual Total Returns</ShortName>
      <MenuCategory></MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>000029 - Disclosure - Risk/Return Detail Data {Elements} - DWS Intermediate Tax-Free Fund (Class T)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dws.com/role/DisclosureRiskReturnDetailDataElementsDWSIntermediateTax-FreeFundClassT</Role>
      <ShortName>Risk/Return Detail Data- DWS Intermediate Tax-Free Fund (Class T)</ShortName>
      <MenuCategory></MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ddtft-20200924.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.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>17</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: 32 fact(s) appearing in ix:hidden were eligible for transformation: rr:ExpenseFootnotesTextBlock, rr:ExpenseHeading, rr:ExpenseNarrativeTextBlock, rr:FeeWaiverOrReimbursementOverAssets, rr:ObjectiveHeading, rr:ObjectivePrimaryTextBlock, rr:PerformanceNarrativeTextBlock, rr:PortfolioTurnoverHeading, rr:PortfolioTurnoverRate, rr:PortfolioTurnoverTextBlock, rr:ProspectusDate, rr:RiskHeading, rr:RiskNarrativeTextBlock, rr:StrategyHeading, rr:StrategyNarrativeTextBlock</Log>
  </Logs>
  <InputFiles>
    <File doctype="485BPOS" original="ddtft-20200924.htm">ddtft-20200924.htm</File>
    <File>ddtft-20200924.xsd</File>
    <File>ddtft-20200924_cal.xml</File>
    <File>ddtft-20200924_def.xml</File>
    <File>ddtft-20200924_lab.xml</File>
    <File>ddtft-20200924_pre.xml</File>
    <File>exa13-tft.htm</File>
    <File>exg3-tft.htm</File>
    <File>exh10-tft.htm</File>
    <File>exh11-tft.htm</File>
    <File>exh4-tft.htm</File>
    <File>exh8-tft.htm</File>
    <File>exj-tft.htm</File>
    <File>exn-tft.htm</File>
    <File>exp2-tft.htm</File>
  </InputFiles>
  <SupplementalFiles>
    <File>graphic1.jpg</File>
    <File>graphic3.jpg</File>
    <File>itff.gif</File>
    <File>itfft.gif</File>
    <File>logo.jpg</File>
    <File>mmbf.gif</File>
    <File>mmbft.gif</File>
    <File>shytff.gif</File>
    <File>shytfft.gif</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>
