<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.4</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>295</ContextCount>
  <ElementCount>499</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>77</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>12</UnitCount>
  <MyReports>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>75000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>75010 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_StatementConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>75020 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_StatementConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>75030 - Statement - Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_StatementConsolidatedStatementsOfOperations</Role>
      <ShortName>Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>75040 - Statement - Consolidated Statements of Comprehensive (Loss) Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/StatementConsolidatedStatementsOfComprehensiveLossIncome</Role>
      <ShortName>Consolidated Statements of Comprehensive (Loss) Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>75050 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_StatementConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>75060 - Statement - Consolidated Statements of Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_StatementConsolidatedStatementsOfStockholdersEquity</Role>
      <ShortName>Consolidated Statements of Stockholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>995410 - Disclosure - Pay vs Performance Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/PvpDisclosure</Role>
      <ShortName>Pay vs Performance Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.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>9</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>995447 - Disclosure - Insider Trading Policies and Procedures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc</Role>
      <ShortName>Insider Trading Policies and Procedures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>995457 - Disclosure - Cybersecurity Risk Management, Strategy, and Governance</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureCybersecurityRiskManagementStrategyAndGovernance</Role>
      <ShortName>Cybersecurity Risk Management, Strategy, and Governance</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>995467 - Disclosure - Organization and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentation</Role>
      <ShortName>Organization and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>995477 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>995487 - Disclosure - Revenue</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureRevenue</Role>
      <ShortName>Revenue</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>995497 - Disclosure - Receivables, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureReceivablesNet</Role>
      <ShortName>Receivables, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>995507 - Disclosure - Inventories, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureInventoriesNet</Role>
      <ShortName>Inventories, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>995517 - Disclosure - Property, Plant and Equipment, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNet</Role>
      <ShortName>Property, Plant and Equipment, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>995527 - Disclosure - Accrued Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureAccruedLiabilities</Role>
      <ShortName>Accrued Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>995537 - Disclosure - Goodwill</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureGoodwill</Role>
      <ShortName>Goodwill</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>995547 - Disclosure - Intangibles, net</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIntangiblesNet</Role>
      <ShortName>Intangibles, net</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>995557 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>995567 - Disclosure - Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureDebt</Role>
      <ShortName>Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>995577 - Disclosure - Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockholdersEquity</Role>
      <ShortName>Stockholders' Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>995587 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>995597 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>995617 - Disclosure - Accumulated Other Comprehensive (Loss) Income ("AOCI")</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAoci</Role>
      <ShortName>Accumulated Other Comprehensive (Loss) Income ("AOCI")</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>995627 - Disclosure - Business Segments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegments</Role>
      <ShortName>Business Segments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>995637 - Disclosure - Earnings Per Share ("EPS")</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEps</Role>
      <ShortName>Earnings Per Share ("EPS")</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>995647 - Disclosure - Stock-based Compensation and Outstanding Awards</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwards</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>995657 - Disclosure - Employee Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEmployeeBenefitPlans</Role>
      <ShortName>Employee Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>995667 - Disclosure - Acquisitions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitions1</Role>
      <ShortName>Acquisitions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>995677 - Disclosure - Selected Quarterly Financial Data (unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnaudited</Role>
      <ShortName>Selected Quarterly Financial Data (unaudited)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>995687 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureSubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>995697 - Disclosure - Organization and Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentationPolicies</Role>
      <ShortName>Organization and Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>995707 - Disclosure - Organization and Basis of Presentation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationTables</Role>
      <ShortName>Organization and Basis of Presentation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentation</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>995717 - Disclosure - Revenue (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureRevenueTables</Role>
      <ShortName>Revenue (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureRevenue</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>995727 - Disclosure - Receivables, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureReceivablesNetTables</Role>
      <ShortName>Receivables, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureReceivablesNet</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>995737 - Disclosure - Inventories, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureInventoriesNetTables</Role>
      <ShortName>Inventories, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureInventoriesNet</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>995747 - Disclosure - Property, Plant and Equipment, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNetTables</Role>
      <ShortName>Property, Plant and Equipment, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNet</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>995757 - Disclosure - Accrued Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureAccruedLiabilitiesTables</Role>
      <ShortName>Accrued Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureAccruedLiabilities</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>995767 - Disclosure - Goodwill (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureGoodwillTables</Role>
      <ShortName>Goodwill (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureGoodwill</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>995777 - Disclosure - Intangibles, net (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIntangiblesNetTables</Role>
      <ShortName>Intangibles, net (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIntangiblesNet</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>995787 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxes</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>995797 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeases</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>995807 - Disclosure - Stockholders' Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockholdersEquityTables</Role>
      <ShortName>Stockholders' Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockholdersEquity</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>995817 - Disclosure - Accumulated Other Comprehensive (Loss) Income ("AOCI") (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAociTables</Role>
      <ShortName>Accumulated Other Comprehensive (Loss) Income ("AOCI") (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAoci</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>995827 - Disclosure - Business Segments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegmentsTables</Role>
      <ShortName>Business Segments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegments</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>995837 - Disclosure - Earnings Per Share ("EPS") (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEpsTables</Role>
      <ShortName>Earnings Per Share ("EPS") (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEps</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>995847 - Disclosure - Stock-based Compensation and Outstanding Awards (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwardsTables</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwards</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>995867 - Disclosure - Acquisitions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitionsTables</Role>
      <ShortName>Acquisitions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitions1</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>995877 - Disclosure - Selected Quarterly Financial Data (unaudited) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnauditedTables</Role>
      <ShortName>Selected Quarterly Financial Data (unaudited) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnaudited</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>995887 - Disclosure - Organization and Basis of Presentation - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetail</Role>
      <ShortName>Organization and Basis of Presentation - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>995897 - Disclosure - Organization and Basis of Presentation - Schedule of Consolidated Statements of Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationScheduleOfConsolidatedStatementsOfOperationsDetails</Role>
      <ShortName>Organization and Basis of Presentation - Schedule of Consolidated Statements of Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>995907 - Disclosure - Organization and Basis of Presentation - Schedule of Consolidated Statements of Comprehensive Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationScheduleOfConsolidatedStatementsOfComprehensiveIncomeDetails</Role>
      <ShortName>Organization and Basis of Presentation - Schedule of Consolidated Statements of Comprehensive Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>995917 - Disclosure - Organization and Basis of Presentation - Schedule of Consolidated Balance Sheets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationScheduleOfConsolidatedBalanceSheetsDetails</Role>
      <ShortName>Organization and Basis of Presentation - Schedule of Consolidated Balance Sheets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>995927 - Disclosure - Organization and Basis of Presentation - Schedule of Consolidated Statements of Cash Flows (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationScheduleOfConsolidatedStatementsOfCashFlowsDetails</Role>
      <ShortName>Organization and Basis of Presentation - Schedule of Consolidated Statements of Cash Flows (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>995937 - Disclosure - Organization and Basis of Presentation - Schedule of Consolidated Statements of Stockholders' Equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationScheduleOfConsolidatedStatementsOfStockholdersEquityDetails</Role>
      <ShortName>Organization and Basis of Presentation - Schedule of Consolidated Statements of Stockholders' Equity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>995947 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetail</Role>
      <ShortName>Summary of Significant Accounting Policies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>995957 - Disclosure - Revenue - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureRevenueAdditionalInformationDetail</Role>
      <ShortName>Revenue - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>995967 - Disclosure - Revenue - Summary of Revenue Disaggregated by Revenue Source (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureRevenueSummaryOfRevenueDisaggregatedByRevenueSourceDetails</Role>
      <ShortName>Revenue - Summary of Revenue Disaggregated by Revenue Source (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>995977 - Disclosure - Receivables, net - Rollforward of Allowance for Doubtful Accounts (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureReceivablesNetRollforwardOfAllowanceForDoubtfulAccountsDetail</Role>
      <ShortName>Receivables, net - Rollforward of Allowance for Doubtful Accounts (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>995987 - Disclosure - Inventories, net - Schedule of Inventories (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureInventoriesNetScheduleOfInventoriesDetail</Role>
      <ShortName>Inventories, net - Schedule of Inventories (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>995997 - Disclosure - Property, Plant and Equipment, net - Summary of Property, Plant and Equipment (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNetSummaryOfPropertyPlantAndEquipmentDetail</Role>
      <ShortName>Property, Plant and Equipment, net - Summary of Property, Plant and Equipment (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>996007 - Disclosure - Property, Plant and Equipment, net - Summary of Property, Plant and Equipment (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNetSummaryOfPropertyPlantAndEquipmentParentheticalDetail</Role>
      <ShortName>Property, Plant and Equipment, net - Summary of Property, Plant and Equipment (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>996017 - Disclosure - Property, Plant and Equipment, net - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosurePropertyPlantAndEquipmentNetAdditionalInformationDetail</Role>
      <ShortName>Property, Plant and Equipment, net - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>996027 - Disclosure - Accrued Liabilities - Summary of Accrued Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureAccruedLiabilitiesSummaryOfAccruedLiabilitiesDetail</Role>
      <ShortName>Accrued Liabilities - Summary of Accrued Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>996037 - Disclosure - Goodwill - Summary of Goodwill Identified by Segment (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureGoodwillSummaryOfGoodwillIdentifiedBySegmentDetail</Role>
      <ShortName>Goodwill - Summary of Goodwill Identified by Segment (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>996047 - Disclosure - Goodwill - Summary of Goodwill Identified by Segment (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureGoodwillSummaryOfGoodwillIdentifiedBySegmentParentheticalDetail</Role>
      <ShortName>Goodwill - Summary of Goodwill Identified by Segment (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>996057 - Disclosure - Intangibles, Net - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIntangiblesNetAdditionalInformationDetail</Role>
      <ShortName>Intangibles, Net - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>996067 - Disclosure - Intangibles, Net - Identified Intangible Assets by Major Classification (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIntangiblesNetIdentifiedIntangibleAssetsByMajorClassificationDetail</Role>
      <ShortName>Intangibles, Net - Identified Intangible Assets by Major Classification (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>996077 - Disclosure - Intangibles, net - Identified Intangible Assets by Major Classification (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureIntangiblesNetIdentifiedIntangibleAssetsByMajorClassificationParentheticalDetail</Role>
      <ShortName>Intangibles, net - Identified Intangible Assets by Major Classification (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>996087 - Disclosure - Intangibles, Net - Schedule of Estimated Amortization of Intangible Assets Excluding Assets Held-for-Sale (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureIntangiblesNetScheduleOfEstimatedAmortizationOfIntangibleAssetsExcludingAssetsHeldforsaleDetail</Role>
      <ShortName>Intangibles, Net - Schedule of Estimated Amortization of Intangible Assets Excluding Assets Held-for-Sale (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>996097 - Disclosure - Income Taxes - Domestic and Foreign Components of Income Before Income Taxes (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureIncomeTaxesDomesticAndForeignComponentsOfIncomeBeforeIncomeTaxesDetail</Role>
      <ShortName>Income Taxes - Domestic and Foreign Components of Income Before Income Taxes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>996107 - Disclosure - Income Taxes - Components of the Provision (Benefit) for Income Taxes (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxesComponentsOfProvisionBenefitForIncomeTaxesDetail</Role>
      <ShortName>Income Taxes - Components of the Provision (Benefit) for Income Taxes (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>996117 - Disclosure - Income Taxes - Difference Between Effective Tax Rate (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxesDifferenceBetweenEffectiveTaxRateDetail</Role>
      <ShortName>Income Taxes - Difference Between Effective Tax Rate (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>996127 - Disclosure - Income Taxes - Income Taxes Paid, by Jurisdiction (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureIncomeTaxesIncomeTaxesPaidByJurisdictionDetails</Role>
      <ShortName>Income Taxes - Income Taxes Paid, by Jurisdiction (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>996137 - Disclosure - Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxesSignificantComponentsOfDeferredTaxAssetsAndLiabilitiesDetail</Role>
      <ShortName>Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>996147 - Disclosure - Income Taxes - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetail</Role>
      <ShortName>Income Taxes - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>996157 - Disclosure - Debt - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureDebtAdditionalInformationDetail</Role>
      <ShortName>Debt - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>996167 - Disclosure - Stockholders' Equity - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockholdersEquityAdditionalInformationDetail</Role>
      <ShortName>Stockholders' Equity - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>996177 - Disclosure - Stockholders' Equity - Schedule of Shares Repurchased (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockholdersEquityScheduleOfSharesRepurchasedDetails</Role>
      <ShortName>Stockholders' Equity - Schedule of Shares Repurchased (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>996187 - Disclosure - Leases - Supplemental Balance Sheet Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesSupplementalBalanceSheetInformationDetail</Role>
      <ShortName>Leases - Supplemental Balance Sheet Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>996207 - Disclosure - Leases - Components of Lease Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesComponentsOfLeaseExpenseDetail</Role>
      <ShortName>Leases - Components of Lease Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>996227 - Disclosure - Leases - Supplemental Cash Flow Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesSupplementalCashFlowInformationDetail</Role>
      <ShortName>Leases - Supplemental Cash Flow Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>996247 - Disclosure - Leases - Maturity of Lease Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesMaturityOfLeaseLiabilitiesDetail</Role>
      <ShortName>Leases - Maturity of Lease Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>996267 - Disclosure - Leases - Maturity of Lease Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureLeasesMaturityOfLeaseLiabilitiesDetails</Role>
      <ShortName>Leases - Maturity of Lease Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>996277 - Disclosure - Leases - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetail</Role>
      <ShortName>Leases - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>996287 - Disclosure - Commitments and Contingencies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureCommitmentsAndContingenciesAdditionalInformationDetail</Role>
      <ShortName>Commitments and Contingencies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>996307 - Disclosure - Accumulated Other Comprehensive (Loss) Income ("AOCI") - Components of Accumulated Other Comprehensive (Loss) Income (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAociComponentsOfAccumulatedOtherComprehensiveLossIncomeDetail</Role>
      <ShortName>Accumulated Other Comprehensive (Loss) Income ("AOCI") - Components of Accumulated Other Comprehensive (Loss) Income (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAociTables</ParentRole>
      <Position>89</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>996317 - Disclosure - Accumulated Other Comprehensive Income (Loss) ("AOCI") - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossAociAdditionalInformationDetail</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) ("AOCI") - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveLossIncomeAociTables</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>996327 - Disclosure - Business Segments - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegmentsAdditionalInformationDetail</Role>
      <ShortName>Business Segments - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>996337 - Disclosure - Business Segments - Summary of Financial Information of Company's Reportable Segments (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegmentsSummaryOfFinancialInformationOfCompanySReportableSegmentsDetail</Role>
      <ShortName>Business Segments - Summary of Financial Information of Company's Reportable Segments (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>996347 - Disclosure - Business Segments - Schedule of Comparison of Approximate Sales Mix in Principal Product Categories (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureBusinessSegmentsScheduleOfComparisonOfApproximateSalesMixInPrincipalProductCategoriesDetail</Role>
      <ShortName>Business Segments - Schedule of Comparison of Approximate Sales Mix in Principal Product Categories (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>996357 - Disclosure - Earnings Per Share ("EPS") - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEpsAdditionalInformationDetail</Role>
      <ShortName>Earnings Per Share ("EPS") - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEpsTables</ParentRole>
      <Position>94</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>996367 - Disclosure - Earnings Per Share ("EPS") - Computation of Basic and Diluted EPS (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEpsComputationOfBasicAndDilutedEpsDetail</Role>
      <ShortName>Earnings Per Share ("EPS") - Computation of Basic and Diluted EPS (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureEarningsPerShareEpsTables</ParentRole>
      <Position>95</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>996387 - Disclosure - Stock-based Compensation and Outstanding Awards - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwardsAdditionalInformationDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>996397 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Stock Option Activity (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwardsSummaryOfStockOptionActivityDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Stock Option Activity (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>996407 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSAs (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockbasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfRsasDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSAs (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>996417 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSAs (Detail) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockbasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfRsasDetailParentheticalDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSAs (Detail) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>996427 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSUs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockbasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfRsusDetails</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSUs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>996437 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSUs (Detail) (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureStockbasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfRsusDetailParentheticalDetails</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of RSUs (Detail) (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>996447 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of PSAs (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfPsasDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of PSAs (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>996457 - Disclosure - Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of PSAs (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/Role_DisclosureStockBasedCompensationAndOutstandingAwardsSummaryOfStatusOfNonvestedSharesOfPsasParentheticalDetail</Role>
      <ShortName>Stock-based Compensation and Outstanding Awards - Summary of Status of Nonvested Shares of PSAs (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>996467 - Disclosure - Employee Benefit Plans - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureEmployeeBenefitPlansAdditionalInformationDetail</Role>
      <ShortName>Employee Benefit Plans - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>996527 - Disclosure - Acquisitions - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitionsAdditionalInformationDetail</Role>
      <ShortName>Acquisitions - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>996537 - Disclosure - Acquisitions - Summary of Purchase Price Allocation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitionsSummaryOfPurchasePriceAllocationDetails</Role>
      <ShortName>Acquisitions - Summary of Purchase Price Allocation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>996557 - Disclosure - Acquisitions - Summary of Purchase Price Allocation (Parenthetical) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureAcquisitionsSummaryOfPurchasePriceAllocationParentheticalDetails</Role>
      <ShortName>Acquisitions - Summary of Purchase Price Allocation (Parenthetical) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="dnow-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>996567 - Disclosure - Selected Quarterly Financial Data (unaudited) - Schedule of change in accounting method for select quarterly financial data (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.dnow.com/20251231/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnauditedScheduleOfChangeInAccountingMethodForSelectQuarterlyFinancialDataDetails</Role>
      <ShortName>Selected Quarterly Financial Data (unaudited) - Schedule of change in accounting method for select quarterly financial data (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.dnow.com/20251231/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnauditedTables</ParentRole>
      <Position>108</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-K" isDefinitelyFs="true" isUsgaap="true" original="dnow-20251231.htm">dnow-20251231.htm</File>
    <File>dnow-20251231.xsd</File>
  </InputFiles>
  <SupplementalFiles>
    <File>img88354990_0.jpg</File>
    <File>img88354990_1.jpg</File>
    <File>img88354990_2.gif</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="4">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="1428">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="7">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="42">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="5">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>false</HasPresentationLinkbase>
  <HasCalculationLinkbase>false</HasCalculationLinkbase>
</FilingSummary>
