<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.22.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>323</ContextCount>
  <ElementCount>386</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>110</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>7</UnitCount>
  <MyReports>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001002 - Statement - Unaudited Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/UnauditedCondensedConsolidatedBalanceSheets</Role>
      <ShortName>Unaudited Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1002003 - Statement - Unaudited Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/UnauditedCondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Unaudited Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1003004 - Statement - Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/UnauditedCondensedConsolidatedStatementsofOperationsandComprehensiveLoss</Role>
      <ShortName>Unaudited Condensed Consolidated Statements of Operations and Comprehensive Loss</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1004005 - Statement - Unaudited Condensed Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Deficit</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/UnauditedCondensedConsolidatedStatementsofChangesinRedeemableConvertiblePreferredStockandStockholdersDeficit</Role>
      <ShortName>Unaudited Condensed Consolidated Statements of Changes in Redeemable Convertible Preferred Stock and Stockholders' Deficit</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1005006 - Statement - Unaudited Condensed Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/UnauditedCondensedConsolidatedStatementsofCashFlows</Role>
      <ShortName>Unaudited Condensed Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>2101101 - Disclosure - Description of business</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Descriptionofbusiness</Role>
      <ShortName>Description of business</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>2103102 - Disclosure - Summary of significant accounting policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Summaryofsignificantaccountingpolicies</Role>
      <ShortName>Summary of significant accounting policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2111103 - Disclosure - Liquidity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Liquidity</Role>
      <ShortName>Liquidity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2113104 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Acquisitions</Role>
      <ShortName>Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2115105 - Disclosure - Reverse Recapitalization</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/ReverseRecapitalization</Role>
      <ShortName>Reverse Recapitalization</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2117106 - Disclosure - Fair value measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Fairvaluemeasurements</Role>
      <ShortName>Fair value measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2123107 - Disclosure - Property and equipment, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Propertyandequipmentnet</Role>
      <ShortName>Property and equipment, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2126108 - Disclosure - Accrued expenses and other current liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Accruedexpensesandothercurrentliabilities</Role>
      <ShortName>Accrued expenses and other current liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2129109 - Disclosure - Debt facilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Debtfacilities</Role>
      <ShortName>Debt facilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2135110 - Disclosure - Warrants</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Warrants</Role>
      <ShortName>Warrants</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2139111 - Disclosure - Stockholders??? deficit and stock-based compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Stockholdersdeficitandstockbasedcompensation</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2156112 - Disclosure - Net loss per share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Netlosspershare</Role>
      <ShortName>Net loss per share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2159113 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Leases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2166114 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2168115 - Disclosure - Income taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Incometaxes</Role>
      <ShortName>Income taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2170116 - Disclosure - Related party transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Relatedpartytransactions</Role>
      <ShortName>Related party transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2172117 - Disclosure - Subsequent events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/Subsequentevents</Role>
      <ShortName>Subsequent events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2204201 - Disclosure - Summary of significant accounting policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesPolicies</Role>
      <ShortName>Summary of significant accounting policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - Summary of significant accounting policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesTables</Role>
      <ShortName>Summary of significant accounting policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Summaryofsignificantaccountingpolicies</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2318302 - Disclosure - Fair value measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/FairvaluemeasurementsTables</Role>
      <ShortName>Fair value measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Fairvaluemeasurements</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2324303 - Disclosure - Property and equipment, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/PropertyandequipmentnetTables</Role>
      <ShortName>Property and equipment, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Propertyandequipmentnet</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2327304 - Disclosure - Accrued expenses and other current liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/AccruedexpensesandothercurrentliabilitiesTables</Role>
      <ShortName>Accrued expenses and other current liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Accruedexpensesandothercurrentliabilities</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2330305 - Disclosure - Debt facilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DebtfacilitiesTables</Role>
      <ShortName>Debt facilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Debtfacilities</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2336306 - Disclosure - Warrants (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/WarrantsTables</Role>
      <ShortName>Warrants (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Warrants</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2340307 - Disclosure - Stockholders??? deficit and stock-based compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationTables</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Stockholdersdeficitandstockbasedcompensation</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2357308 - Disclosure - Net loss per share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/NetlosspershareTables</Role>
      <ShortName>Net loss per share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Netlosspershare</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2360309 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.volta.com/role/Leases</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2402401 - Disclosure - Description of business (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DescriptionofbusinessDetails</Role>
      <ShortName>Description of business (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Descriptionofbusiness</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Summary of significant accounting policies - Additional information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesAdditionalinformationDetails</Role>
      <ShortName>Summary of significant accounting policies - Additional information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2407403 - Disclosure - Summary of significant accounting policies - Concentration of risk (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesConcentrationofriskDetails</Role>
      <ShortName>Summary of significant accounting policies - Concentration of risk (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2408404 - Disclosure - Summary of significant accounting policies - Property and equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesPropertyandequipmentDetails</Role>
      <ShortName>Summary of significant accounting policies - Property and equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2409405 - Disclosure - Summary of significant accounting policies - Disaggregation of revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesDisaggregationofrevenueDetails</Role>
      <ShortName>Summary of significant accounting policies - Disaggregation of revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2410406 - Disclosure - Summary of significant accounting policies - Equity issuance costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SummaryofsignificantaccountingpoliciesEquityissuancecostsDetails</Role>
      <ShortName>Summary of significant accounting policies - Equity issuance costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2412407 - Disclosure - Liquidity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LiquidityDetails</Role>
      <ShortName>Liquidity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Liquidity</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2414408 - Disclosure - Acquisitions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/AcquisitionsDetails</Role>
      <ShortName>Acquisitions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Acquisitions</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2416409 - Disclosure - Reverse Recapitalization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/ReverseRecapitalizationDetails</Role>
      <ShortName>Reverse Recapitalization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/ReverseRecapitalization</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2419410 - Disclosure - Fair value measurements - Derivative Instruments at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/FairvaluemeasurementsDerivativeInstrumentsatFairValueDetails</Role>
      <ShortName>Fair value measurements - Derivative Instruments at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2420411 - Disclosure - Fair value measurements - Quantitative Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/FairvaluemeasurementsQuantitativeInformationDetails</Role>
      <ShortName>Fair value measurements - Quantitative Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2421412 - Disclosure - Fair value measurements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/FairvaluemeasurementsAdditionalInformationDetails</Role>
      <ShortName>Fair value measurements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2422413 - Disclosure - Fair value measurements - Changes in Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/FairvaluemeasurementsChangesinFairValueDetails</Role>
      <ShortName>Fair value measurements - Changes in Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2425414 - Disclosure - Property and equipment, net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/PropertyandequipmentnetDetails</Role>
      <ShortName>Property and equipment, net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/PropertyandequipmentnetTables</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2428415 - Disclosure - Accrued expenses and other current liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/AccruedexpensesandothercurrentliabilitiesDetails</Role>
      <ShortName>Accrued expenses and other current liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/AccruedexpensesandothercurrentliabilitiesTables</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2431416 - Disclosure - Debt facilities - Schedule of Debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DebtfacilitiesScheduleofDebtDetails</Role>
      <ShortName>Debt facilities - Schedule of Debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2432417 - Disclosure - Debt facilities - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DebtfacilitiesAdditionalInformationDetails</Role>
      <ShortName>Debt facilities - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2433418 - Disclosure - Debt facilities - PPP Loan Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DebtfacilitiesPPPLoanPaymentsDetails</Role>
      <ShortName>Debt facilities - PPP Loan Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2434419 - Disclosure - Debt facilities - Future Maturities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/DebtfacilitiesFutureMaturitiesDetails</Role>
      <ShortName>Debt facilities - Future Maturities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2437420 - Disclosure - Warrants - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/WarrantsAdditionalInformationDetails</Role>
      <ShortName>Warrants - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2438421 - Disclosure - Warrants - Schedule of Activities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/WarrantsScheduleofActivitiesDetails</Role>
      <ShortName>Warrants - Schedule of Activities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2441422 - Disclosure - Stockholders??? deficit and stock-based compensation - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationAdditionalInformationDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2442423 - Disclosure - Stockholders??? deficit and stock-based compensation - Convertible Preferred Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationConvertiblePreferredStockDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Convertible Preferred Stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2443424 - Disclosure - Stockholders??? deficit and stock-based compensation - Common sock activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationCommonsockactivityDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Common sock activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2444425 - Disclosure - Stockholders??? deficit and stock-based compensation - Volta stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationVoltastockDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Volta stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2445426 - Disclosure - Stockholders??? deficit and stock-based compensation - Shares reserved for issuance (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationSharesreservedforissuanceDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Shares reserved for issuance (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2446427 - Disclosure - Stockholders??? deficit and stock-based compensation - Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationPlansDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationTables</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2447428 - Disclosure - Stockholders??? deficit and stock-based compensation - Option reward activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationOptionrewardactivityDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Option reward activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2448429 - Disclosure - Stockholders??? deficit and stock-based compensation - Stock option activity, narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationStockoptionactivitynarrativeDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Stock option activity, narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2449430 - Disclosure - Stockholders??? deficit and stock-based compensation - Restricted stock units, narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationRestrictedstockunitsnarrativeDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Restricted stock units, narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2450431 - Disclosure - Stockholders??? deficit and stock-based compensation - Restricted stock units activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationRestrictedstockunitsactivityDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Restricted stock units activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2451432 - Disclosure - Stockholders??? deficit and stock-based compensation - Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationAssumptionsDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2452433 - Disclosure - Stockholders??? deficit and stock-based compensation - Stock-based compensation and expense, narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationStockbasedcompensationandexpensenarrativeDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Stock-based compensation and expense, narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2453434 - Disclosure - Stockholders??? deficit and stock-based compensation - Significant modifications and Compensation expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationSignificantmodificationsandCompensationexpenseDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Significant modifications and Compensation expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2454435 - Disclosure - Stockholders??? deficit and stock-based compensation - Schedule of significant modifications (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationScheduleofsignificantmodificationsDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Schedule of significant modifications (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2455436 - Disclosure - Stockholders??? deficit and stock-based compensation - Partial recourse promissory notes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.volta.com/role/StockholdersdeficitandstockbasedcompensationPartialrecoursepromissorynotesDetails</Role>
      <ShortName>Stockholders??? deficit and stock-based compensation - Partial recourse promissory notes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2458437 - Disclosure - Net loss per share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/NetlosspershareDetails</Role>
      <ShortName>Net loss per share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/NetlosspershareTables</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2461438 - Disclosure - Leases - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesAdditionalInformationDetails</Role>
      <ShortName>Leases - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2462439 - Disclosure - Leases - Balance Sheets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesBalanceSheetsDetails</Role>
      <ShortName>Leases - Balance Sheets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2463440 - Disclosure - Leases - Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesCostsDetails</Role>
      <ShortName>Leases - Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2464441 - Disclosure - Leases - Cash Flows (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesCashFlowsDetails</Role>
      <ShortName>Leases - Cash Flows (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2465442 - Disclosure - Leases - Maturities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/LeasesMaturitiesDetails</Role>
      <ShortName>Leases - Maturities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2467443 - Disclosure - Commitments and Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/CommitmentsandContingenciesDetails</Role>
      <ShortName>Commitments and Contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/CommitmentsandContingencies</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2469444 - Disclosure - Income taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/IncometaxesDetails</Role>
      <ShortName>Income taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Incometaxes</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2471445 - Disclosure - Related party transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/RelatedpartytransactionsDetails</Role>
      <ShortName>Related party transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Relatedpartytransactions</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="vlta-20220331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2473446 - Disclosure - Subsequent events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.volta.com/role/SubsequenteventsDetails</Role>
      <ShortName>Subsequent events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.volta.com/role/Subsequentevents</ParentRole>
      <Position>79</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="10-Q" original="vlta-20220331.htm">vlta-20220331.htm</File>
    <File>vlta-20220331.xsd</File>
    <File>vlta-20220331_cal.xml</File>
    <File>vlta-20220331_def.xml</File>
    <File>vlta-20220331_lab.xml</File>
    <File>vlta-20220331_pre.xml</File>
    <File>volta-exx311q12022.htm</File>
    <File>volta-exx312q12022.htm</File>
    <File>volta-exx321q12022.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="841">http://fasb.org/us-gaap/2021-01-31</BaseTaxonomy>
    <BaseTaxonomy items="34">http://xbrl.sec.gov/dei/2021q4</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
