<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>265</ContextCount>
  <ElementCount>306</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>88</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>8</UnitCount>
  <MyReports>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - Condensed Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofOperations</Role>
      <ShortName>Condensed Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - Condensed Consolidated Statements of Comprehensive Loss</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofComprehensiveLoss</Role>
      <ShortName>Condensed Consolidated Statements of Comprehensive Loss</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - Condensed Consolidated Statements of Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofShareholdersEquity</Role>
      <ShortName>Condensed Consolidated Statements of Shareholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - Condensed Consolidated Statements of Shareholders' Equity (Parentheticals)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofShareholdersEquityParentheticals</Role>
      <ShortName>Condensed Consolidated Statements of Shareholders' Equity (Parentheticals)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Statement - Condensed Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofCashFlows</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Statement - Condensed Consolidated Statements of Cash Flows (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/CondensedConsolidatedStatementsofCashFlowsParenthetical</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - General</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/General</Role>
      <ShortName>General</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Recently Issued and Adopted Accounting Pronouncements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/RecentlyIssuedandAdoptedAccountingPronouncements</Role>
      <ShortName>Recently Issued and Adopted Accounting Pronouncements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/Acquisitions</Role>
      <ShortName>Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Revisions in Estimates</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/RevisionsinEstimates</Role>
      <ShortName>Revisions in Estimates</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Disaggregation of Revenue</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DisaggregationofRevenue</Role>
      <ShortName>Disaggregation of Revenue</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - Unearned Revenue</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/UnearnedRevenue</Role>
      <ShortName>Unearned Revenue</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - Contract Assets and Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ContractAssetsandLiabilities</Role>
      <ShortName>Contract Assets and Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - Receivables, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/Receivablesnet</Role>
      <ShortName>Receivables, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - Fair Value Measurement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/FairValueMeasurement</Role>
      <ShortName>Fair Value Measurement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - Construction Joint Ventures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ConstructionJointVentures</Role>
      <ShortName>Construction Joint Ventures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - Investments in Affiliates</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/InvestmentsinAffiliates</Role>
      <ShortName>Investments in Affiliates</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - Property and Equipment, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/PropertyandEquipmentnet</Role>
      <ShortName>Property and Equipment, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - Accrued Expenses and Other Current Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AccruedExpensesandOtherCurrentLiabilities</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/Debt</Role>
      <ShortName>Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - Weighted Average Shares Outstanding and Net Loss Per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShare</Role>
      <ShortName>Weighted Average Shares Outstanding and Net Loss Per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - Contingencies - Legal Proceedings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ContingenciesLegalProceedings</Role>
      <ShortName>Contingencies - Legal Proceedings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - Reportable Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReportableSegmentInformation</Role>
      <ShortName>Reportable Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AcquisitionsTables</Role>
      <ShortName>Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/Acquisitions</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Disaggregation of Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DisaggregationofRevenueTables</Role>
      <ShortName>Disaggregation of Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/DisaggregationofRevenue</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Unearned Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/UnearnedRevenueTables</Role>
      <ShortName>Unearned Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/UnearnedRevenue</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Contract Assets and Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ContractAssetsandLiabilitiesTables</Role>
      <ShortName>Contract Assets and Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/ContractAssetsandLiabilities</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Receivables, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReceivablesnetTables</Role>
      <ShortName>Receivables, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/Receivablesnet</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Fair Value Measurement (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/FairValueMeasurementTables</Role>
      <ShortName>Fair Value Measurement (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/FairValueMeasurement</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Construction Joint Ventures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ConstructionJointVenturesTables</Role>
      <ShortName>Construction Joint Ventures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/ConstructionJointVentures</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Investments in Affiliates (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/InvestmentsinAffiliatesTables</Role>
      <ShortName>Investments in Affiliates (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/InvestmentsinAffiliates</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Property and Equipment, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/PropertyandEquipmentnetTables</Role>
      <ShortName>Property and Equipment, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/PropertyandEquipmentnet</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/AccruedExpensesandOtherCurrentLiabilities</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DebtTables</Role>
      <ShortName>Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/Debt</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Weighted Average Shares Outstanding and Net Loss Per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShareTables</Role>
      <ShortName>Weighted Average Shares Outstanding and Net Loss Per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShare</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/IncomeTaxes</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Reportable Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReportableSegmentInformationTables</Role>
      <ShortName>Reportable Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/ReportableSegmentInformation</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - General (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/GeneralDetails</Role>
      <ShortName>General (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/General</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Acquisitions - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AcquisitionsNarrativeDetails</Role>
      <ShortName>Acquisitions - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Acquisitions - Schedule of Purchase Price and Assumed Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AcquisitionsScheduleofPurchasePriceandAssumedLiabilitiesDetails</Role>
      <ShortName>Acquisitions - Schedule of Purchase Price and Assumed Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Revisions in Estimates (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/RevisionsinEstimatesDetails</Role>
      <ShortName>Revisions in Estimates (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/RevisionsinEstimates</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Disaggregation of Revenue - Schedule of Disaggregation of Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DisaggregationofRevenueScheduleofDisaggregationofRevenueDetails</Role>
      <ShortName>Disaggregation of Revenue - Schedule of Disaggregation of Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Unearned Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/UnearnedRevenueDetails</Role>
      <ShortName>Unearned Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/UnearnedRevenueTables</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Unearned Revenue - Schedule of Unearned Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/UnearnedRevenueScheduleofUnearnedRevenueDetails</Role>
      <ShortName>Unearned Revenue - Schedule of Unearned Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Contract Assets and Liabilities - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ContractAssetsandLiabilitiesNarrativeDetails</Role>
      <ShortName>Contract Assets and Liabilities - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Contract Assets and Liabilities - Component of Contract Asset and Liability Balances (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ContractAssetsandLiabilitiesComponentofContractAssetandLiabilityBalancesDetails</Role>
      <ShortName>Contract Assets and Liabilities - Component of Contract Asset and Liability Balances (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Receivables, net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReceivablesnetDetails</Role>
      <ShortName>Receivables, net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/ReceivablesnetTables</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Receivables, net - Schedule of Receivables (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReceivablesnetScheduleofReceivablesDetails</Role>
      <ShortName>Receivables, net - Schedule of Receivables (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Fair Value Measurement - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/FairValueMeasurementNarrativeDetails</Role>
      <ShortName>Fair Value Measurement - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Fair Value Measurement - Assets and Liabilities at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/FairValueMeasurementAssetsandLiabilitiesatFairValueDetails</Role>
      <ShortName>Fair Value Measurement - Assets and Liabilities at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Fair Value Measurement - Schedule of Carrying and Fair Value Amounts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/FairValueMeasurementScheduleofCarryingandFairValueAmountsDetails</Role>
      <ShortName>Fair Value Measurement - Schedule of Carrying and Fair Value Amounts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Construction Joint Ventures - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ConstructionJointVenturesNarrativeDetails</Role>
      <ShortName>Construction Joint Ventures - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Construction Joint Ventures - Unconsolidated Construction Joint Ventures Financial Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ConstructionJointVenturesUnconsolidatedConstructionJointVenturesFinancialInformationDetails</Role>
      <ShortName>Construction Joint Ventures - Unconsolidated Construction Joint Ventures Financial Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ConstructionJointVenturesScheduleofUnconsolidatedConstructionJointVenturesRevenueandCostsDetails</Role>
      <ShortName>Construction Joint Ventures - Schedule of Unconsolidated Construction Joint Ventures Revenue and Costs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Investments in Affiliates - Equity Method Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/InvestmentsinAffiliatesEquityMethodInvestmentsDetails</Role>
      <ShortName>Investments in Affiliates - Equity Method Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Investments in Affiliates - Summarized Balance Sheet Information for Equity Method Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/InvestmentsinAffiliatesSummarizedBalanceSheetInformationforEquityMethodInvestmentsDetails</Role>
      <ShortName>Investments in Affiliates - Summarized Balance Sheet Information for Equity Method Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Property and Equipment, net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/PropertyandEquipmentnetDetails</Role>
      <ShortName>Property and Equipment, net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/PropertyandEquipmentnetTables</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Accrued Expenses and Other Current Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/AccruedExpensesandOtherCurrentLiabilitiesDetails</Role>
      <ShortName>Accrued Expenses and Other Current Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Debt - Schedule of Long-term Debt and Credit Agreement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DebtScheduleofLongtermDebtandCreditAgreementDetails</Role>
      <ShortName>Debt - Schedule of Long-term Debt and Credit Agreement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - Debt - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/DebtNarrativeDetails</Role>
      <ShortName>Debt - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - Weighted Average Shares Outstanding and Net Loss Per Share - Reconciliation of the Weighted Average Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShareReconciliationoftheWeightedAverageSharesDetails</Role>
      <ShortName>Weighted Average Shares Outstanding and Net Loss Per Share - Reconciliation of the Weighted Average Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - Weighted Average Shares Outstanding and Net Loss Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShareDetails</Role>
      <ShortName>Weighted Average Shares Outstanding and Net Loss Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.graniteconstruction.com/role/WeightedAverageSharesOutstandingandNetLossPerShareTables</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - Income Taxes - Schedule of (Benefit from) Provision for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/IncomeTaxesScheduleofBenefitfromProvisionforIncomeTaxesDetails</Role>
      <ShortName>Income Taxes - Schedule of (Benefit from) Provision for Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - Reportable Segment Information - Segment Reporting Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReportableSegmentInformationSegmentReportingInformationDetails</Role>
      <ShortName>Reportable Segment Information - Segment Reporting Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="gva-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - Reportable Segment Information - Reconciliation of Segment Gross (Loss) Profit to Consolidated Loss (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.graniteconstruction.com/role/ReportableSegmentInformationReconciliationofSegmentGrossLossProfittoConsolidatedLossDetails</Role>
      <ShortName>Reportable Segment Information - Reconciliation of Segment Gross (Loss) Profit to Consolidated Loss (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</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" isDefinitelyFs="true" isUsgaap="true" original="gva-20260331.htm">gva-20260331.htm</File>
    <File>gva-20260331.xsd</File>
    <File>gva-20260331_cal.xml</File>
    <File>gva-20260331_def.xml</File>
    <File>gva-20260331_lab.xml</File>
    <File>gva-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>gva-20260331_g1.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="833">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="29">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
