<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.21.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>74</ContextCount>
  <ElementCount>295</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>21</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>4</UnitCount>
  <MyReports>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>000 - Document - Document And Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>001 - Statement - Balance Sheet</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ConsolidatedBalanceSheet</Role>
      <ShortName>Balance Sheet</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>002 - Statement - Balance Sheet (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ConsolidatedBalanceSheet_Parentheticals</Role>
      <ShortName>Balance Sheet (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>003 - Statement - Statement of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ConsolidatedIncomeStatement</Role>
      <ShortName>Statement of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>004 - Statement - Statement of Changes in Stockholders??? Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ShareholdersEquityType2or3</Role>
      <ShortName>Statement of Changes in Stockholders??? Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>005 - Statement - Statement of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ConsolidatedCashFlow</Role>
      <ShortName>Statement of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>006 - Disclosure - Description of Organization and Business Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/DescriptionofOrganizationandBusinessOperations</Role>
      <ShortName>Description of Organization and Business Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>007 - Disclosure - Restatement of Previously Issued Financial Statements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatements</Role>
      <ShortName>Restatement of Previously Issued Financial Statements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>008 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPolicies</Role>
      <ShortName>Basis of Presentation and Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>009 - Disclosure - Initial Public Offering</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/InitialPublicOffering</Role>
      <ShortName>Initial Public Offering</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>010 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>011 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>012 - Disclosure - Derivative Warrant Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/DerivativeWarrantLiabilities</Role>
      <ShortName>Derivative Warrant Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>013 - Disclosure - Class A Common Stock Subject to Possible Redemption</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemption</Role>
      <ShortName>Class A Common Stock Subject to Possible Redemption</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>014 - Disclosure - Stockholders??? Deficit</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/StockholdersDeficit</Role>
      <ShortName>Stockholders??? Deficit</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>015 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>016 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>017 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>018 - Disclosure - Accounting Policies, by Policy (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/AccountingPoliciesByPolicy</Role>
      <ShortName>Accounting Policies, by Policy (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPolicies</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>019 - Disclosure - Restatement of Previously Issued Financial Statements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsTables</Role>
      <ShortName>Restatement of Previously Issued Financial Statements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatements</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>020 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesTables</Role>
      <ShortName>Basis of Presentation and Summary of Significant Accounting Policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPolicies</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>021 - Disclosure - Class A Common Stock Subject to Possible Redemption (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemptionTables</Role>
      <ShortName>Class A Common Stock Subject to Possible Redemption (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemption</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>022 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/FairValueMeasurements</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>023 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/IncomeTaxes</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>024 - Disclosure - Description of Organization and Business Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/DescriptionofOrganizationandBusinessOperationsDetails</Role>
      <ShortName>Description of Organization and Business Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/DescriptionofOrganizationandBusinessOperations</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>025 - Disclosure - Restatement of Previously Issued Financial Statements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsDetails</Role>
      <ShortName>Restatement of Previously Issued Financial Statements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsTables</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>026 - Disclosure - Restatement of Previously Issued Financial Statements (Details) - Schedule of balance sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofbalancesheetsTable</Role>
      <ShortName>Restatement of Previously Issued Financial Statements (Details) - Schedule of balance sheets</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsTables</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>027 - Disclosure - Restatement of Previously Issued Financial Statements (Details) - Schedule of cash flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofcashflowsTable</Role>
      <ShortName>Restatement of Previously Issued Financial Statements (Details) - Schedule of cash flows</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsTables</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>028 - Disclosure - Restatement of Previously Issued Financial Statements (Details) - Schedule of operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofoperationsTable</Role>
      <ShortName>Restatement of Previously Issued Financial Statements (Details) - Schedule of operations</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RestatementofPreviouslyIssuedFinancialStatementsTables</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>029 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesDetails</Role>
      <ShortName>Basis of Presentation and Summary of Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesTables</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>030 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details) - Schedule of basic and diluted net income (loss) per share for each class of common stock</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofbasicanddilutednetincomelosspershareforeachclassofcommonstockTable</Role>
      <ShortName>Basis of Presentation and Summary of Significant Accounting Policies (Details) - Schedule of basic and diluted net income (loss) per share for each class of common stock</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/BasisofPresentationandSummaryofSignificantAccountingPoliciesTables</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>031 - Disclosure - Initial Public Offering (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/InitialPublicOfferingDetails</Role>
      <ShortName>Initial Public Offering (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/InitialPublicOffering</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>032 - Disclosure - Related Party Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/RelatedPartyTransactionsDetails</Role>
      <ShortName>Related Party Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/RelatedPartyTransactions</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>033 - Disclosure - Commitments and Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/CommitmentsandContingenciesDetails</Role>
      <ShortName>Commitments and Contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/CommitmentsandContingencies</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>034 - Disclosure - Derivative Warrant Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/DerivativeWarrantLiabilitiesDetails</Role>
      <ShortName>Derivative Warrant Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/DerivativeWarrantLiabilities</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>035 - Disclosure - Class A Common Stock Subject to Possible Redemption (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemptionDetails</Role>
      <ShortName>Class A Common Stock Subject to Possible Redemption (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemptionTables</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>036 - Disclosure - Class A Common Stock Subject to Possible Redemption (Details) - Schedule of class A common stock subject to possible redemption reflected on the balance sheet</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofclassAcommonstocksubjecttopossibleredemptionreflectedonthebalancesheetTable</Role>
      <ShortName>Class A Common Stock Subject to Possible Redemption (Details) - Schedule of class A common stock subject to possible redemption reflected on the balance sheet</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/ClassACommonStockSubjecttoPossibleRedemptionTables</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>037 - Disclosure - Stockholders??? Deficit (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/StockholdersDeficitDetails</Role>
      <ShortName>Stockholders??? Deficit (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/StockholdersDeficit</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>038 - Disclosure - Fair Value Measurements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/FairValueMeasurementsDetails</Role>
      <ShortName>Fair Value Measurements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>039 - Disclosure - Fair Value Measurements (Details) - Schedule of fair value on a recurring basis</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleoffairvalueonarecurringbasisTable</Role>
      <ShortName>Fair Value Measurements (Details) - Schedule of fair value on a recurring basis</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>040 - Disclosure - Fair Value Measurements (Details) - Schedule of quantitative information regarding Level 3 fair value measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofquantitativeinformationregardingLevel3fairvaluemeasurementsTable</Role>
      <ShortName>Fair Value Measurements (Details) - Schedule of quantitative information regarding Level 3 fair value measurements</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>041 - Disclosure - Fair Value Measurements (Details) - Schedule of changes in fair value of warrant liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofchangesinfairvalueofwarrantliabilitiesTable</Role>
      <ShortName>Fair Value Measurements (Details) - Schedule of changes in fair value of warrant liabilities</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>042 - Disclosure - Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/IncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/IncomeTaxesTables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>043 - Disclosure - Income Taxes (Details) - Schedule of income tax provision (benefit)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofincometaxprovisionbenefitTable</Role>
      <ShortName>Income Taxes (Details) - Schedule of income tax provision (benefit)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/IncomeTaxesTables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>044 - Disclosure - Income Taxes (Details) - Schedule of net deferred tax assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofnetdeferredtaxassetsTable</Role>
      <ShortName>Income Taxes (Details) - Schedule of net deferred tax assets</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/IncomeTaxesTables</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="dune-20201231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>045 - Disclosure - Income Taxes (Details) - Schedule of reconciliation of statutory federal income tax rate (benefit)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.duneacquisition.com/role/ScheduleofreconciliationofstatutoryfederalincometaxratebenefitTable</Role>
      <ShortName>Income Taxes (Details) - Schedule of reconciliation of statutory federal income tax rate (benefit)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.duneacquisition.com/role/IncomeTaxesTables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>dune-20201231.xml</File>
    <File>dune-20201231.xsd</File>
    <File>dune-20201231_cal.xml</File>
    <File>dune-20201231_def.xml</File>
    <File>dune-20201231_lab.xml</File>
    <File>dune-20201231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/us-gaap/2021-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2021-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2021</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
