<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.4</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>400</ContextCount>
  <ElementCount>638</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>125</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>14</UnitCount>
  <MyReports>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0000002 - Document - Audit Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/AuditInformation</Role>
      <ShortName>Audit Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952151 - Statement - CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONSOLIDATEDBALANCESHEETS</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952152 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONSOLIDATEDBALANCESHEETSParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952153 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONSOLIDATEDSTATEMENTSOFOPERATIONSANDCOMPREHENSIVELOSS</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952154 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS??? EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSTOCKHOLDERSEQUITY</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS??? EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952155 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONSOLIDATEDSTATEMENTSOFCASHFLOWS</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952156 - Disclosure - DESCRIPTION OF THE BUSINESS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/DESCRIPTIONOFTHEBUSINESS</Role>
      <ShortName>DESCRIPTION OF THE BUSINESS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952157 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIES</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - REVENUES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUES</Role>
      <ShortName>REVENUES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONS</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIES</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTS</Role>
      <ShortName>FAIR VALUE OF FINANCIAL INSTRUMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - INVENTORIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INVENTORIES</Role>
      <ShortName>INVENTORIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - PREPAIDS AND OTHER CURRENT ASSETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PREPAIDSANDOTHERCURRENTASSETS</Role>
      <ShortName>PREPAIDS AND OTHER CURRENT ASSETS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - ASSETS HELD FOR SALE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/ASSETSHELDFORSALE</Role>
      <ShortName>ASSETS HELD FOR SALE</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - PROPERTY, PLANT AND EQUIPMENT, NET</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PROPERTYPLANTANDEQUIPMENTNET</Role>
      <ShortName>PROPERTY, PLANT AND EQUIPMENT, NET</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNET</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - LOAN AGREEMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LOANAGREEMENTS</Role>
      <ShortName>LOAN AGREEMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - STOCKHOLDERS??? EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKHOLDERSEQUITY</Role>
      <ShortName>STOCKHOLDERS??? EQUITY</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - STOCK-BASED COMPENSATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATION</Role>
      <ShortName>STOCK-BASED COMPENSATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - EMPLOYEE BENEFITS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/EMPLOYEEBENEFITS</Role>
      <ShortName>EMPLOYEE BENEFITS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - LEASES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LEASES</Role>
      <ShortName>LEASES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - COMMITMENTS AND CONTINGENCIES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/COMMITMENTSANDCONTINGENCIES</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - INCOME TAXES</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXES</Role>
      <ShortName>INCOME TAXES</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - NET LOSS PER SHARE</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/NETLOSSPERSHARE</Role>
      <ShortName>NET LOSS PER SHARE</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - SEGMENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SEGMENTS</Role>
      <ShortName>SEGMENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATION</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - RELATED PARTY TRANSACTIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/RELATEDPARTYTRANSACTIONS</Role>
      <ShortName>RELATED PARTY TRANSACTIONS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - SUBSEQUENT EVENTS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SUBSEQUENTEVENTS</Role>
      <ShortName>SUBSEQUENT EVENTS</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.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>31</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.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>32</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure</Role>
      <ShortName>Cybersecurity Risk Management and Strategy Disclosure</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIESPolicies</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIESTables</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIES</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - REVENUES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUESTables</Role>
      <ShortName>REVENUES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/REVENUES</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSTables</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONS</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIESTables</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIES</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTSTables</Role>
      <ShortName>FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTS</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - INVENTORIES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INVENTORIESTables</Role>
      <ShortName>INVENTORIES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/INVENTORIES</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - PREPAIDS AND OTHER CURRENT ASSETS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PREPAIDSANDOTHERCURRENTASSETSTables</Role>
      <ShortName>PREPAIDS AND OTHER CURRENT ASSETS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/PREPAIDSANDOTHERCURRENTASSETS</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - PROPERTY, PLANT AND EQUIPMENT, NET (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PROPERTYPLANTANDEQUIPMENTNETTables</Role>
      <ShortName>PROPERTY, PLANT AND EQUIPMENT, NET (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/PROPERTYPLANTANDEQUIPMENTNET</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNETTables</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNET</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - STOCKHOLDERS??? EQUITY (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKHOLDERSEQUITYTables</Role>
      <ShortName>STOCKHOLDERS??? EQUITY (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/STOCKHOLDERSEQUITY</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - STOCK-BASED COMPENSATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATIONTables</Role>
      <ShortName>STOCK-BASED COMPENSATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATION</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - LEASES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LEASESTables</Role>
      <ShortName>LEASES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/LEASES</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - INCOME TAXES (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESTables</Role>
      <ShortName>INCOME TAXES (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/INCOMETAXES</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - NET LOSS PER SHARE (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/NETLOSSPERSHARETables</Role>
      <ShortName>NET LOSS PER SHARE (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/NETLOSSPERSHARE</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - SEGMENTS (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SEGMENTSTables</Role>
      <ShortName>SEGMENTS (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/SEGMENTS</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATIONTables</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATION</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIESAdditionalInformationDetails</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - SIGNIFICANT ACCOUNTING POLICIES - Schedule of Useful Lives of Property and Equipment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SIGNIFICANTACCOUNTINGPOLICIESScheduleofUsefulLivesofPropertyandEquipmentDetails</Role>
      <ShortName>SIGNIFICANT ACCOUNTING POLICIES - Schedule of Useful Lives of Property and Equipment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - REVENUES - Schedule of Reconciliation of Disaggregation of Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUESScheduleofReconciliationofDisaggregationofRevenueDetails</Role>
      <ShortName>REVENUES - Schedule of Reconciliation of Disaggregation of Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - REVENUES - Schedule of Balances Related to Enforceable Contracts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUESScheduleofBalancesRelatedtoEnforceableContractsDetails</Role>
      <ShortName>REVENUES - Schedule of Balances Related to Enforceable Contracts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - REVENUES - Schedule of Changes in Contract Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUESScheduleofChangesinContractLiabilitiesDetails</Role>
      <ShortName>REVENUES - Schedule of Changes in Contract Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - REVENUES - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/REVENUESAdditionalInformationDetails</Role>
      <ShortName>REVENUES - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSNarrativeDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Estimates Fair Value of Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSScheduleofEstimatesFairValueofAssetsAcquiredandLiabilitiesAssumedDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Estimates Fair Value of Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Preliminary Identifiable Intangible Assets Acquired and the Related Expected Lives for the Finite-lived Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSScheduleofPreliminaryIdentifiableIntangibleAssetsAcquiredandtheRelatedExpectedLivesfortheFinitelivedIntangibleAssetsDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Preliminary Identifiable Intangible Assets Acquired and the Related Expected Lives for the Finite-lived Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Unaudited Consolidated Pro Forma Operating (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSUnauditedConsolidatedProFormaOperatingDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Unaudited Consolidated Pro Forma Operating (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS- Asset Acquisition Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSAssetAcquisitionNarrativeDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS- Asset Acquisition Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Fair Value of the Assets Acquired and the Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/BUSINESSCOMBINATIONSANDASSETACQUISITIONSScheduleofFairValueoftheAssetsAcquiredandtheLiabilitiesAssumedDetails</Role>
      <ShortName>BUSINESS COMBINATIONS AND ASSET ACQUISITIONS - Schedule of Fair Value of the Assets Acquired and the Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash and Cash Equivalents and Marketable Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIESScheduleofCashandCashEquivalentsandMarketableSecuritiesDetails</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash and Cash Equivalents and Marketable Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash Equivalents and Marketable Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIESScheduleofCashEquivalentsandMarketableSecuritiesDetails</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash Equivalents and Marketable Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash Equivalents and Marketable Securities with Unrealized Losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIESScheduleofCashEquivalentsandMarketableSecuritieswithUnrealizedLossesDetails</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Cash Equivalents and Marketable Securities with Unrealized Losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Contractual Maturities of Marketable Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CASHANDCASHEQUIVALENTSANDMARKETABLESECURITIESScheduleofContractualMaturitiesofMarketableSecuritiesDetails</Role>
      <ShortName>CASH AND CASH EQUIVALENTS AND MARKETABLE SECURITIES - Schedule of Contractual Maturities of Marketable Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTSScheduleofFinancialAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails</Role>
      <ShortName>FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS - Contingent Consideration Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTSContingentConsiderationObligationsDetails</Role>
      <ShortName>FAIR VALUE OF FINANCIAL INSTRUMENTS - Contingent Consideration Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/FAIRVALUEOFFINANCIALINSTRUMENTSAdditionalInformationDetails</Role>
      <ShortName>FAIR VALUE OF FINANCIAL INSTRUMENTS - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - INVENTORIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INVENTORIESDetails</Role>
      <ShortName>INVENTORIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/INVENTORIESTables</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - PREPAIDS AND OTHER CURRENT ASSETS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PREPAIDSANDOTHERCURRENTASSETSDetails</Role>
      <ShortName>PREPAIDS AND OTHER CURRENT ASSETS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/PREPAIDSANDOTHERCURRENTASSETSTables</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - ASSETS HELD FOR SALE (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/ASSETSHELDFORSALEDetails</Role>
      <ShortName>ASSETS HELD FOR SALE (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/ASSETSHELDFORSALE</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - PROPERTY, PLANT AND EQUIPMENT, NET - Schedule of Property, Plant and Equipment, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PROPERTYPLANTANDEQUIPMENTNETScheduleofPropertyPlantandEquipmentNetDetails</Role>
      <ShortName>PROPERTY, PLANT AND EQUIPMENT, NET - Schedule of Property, Plant and Equipment, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - PROPERTY, PLANT AND EQUIPMENT, NET - Schedule of Depreciation Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/PROPERTYPLANTANDEQUIPMENTNETScheduleofDepreciationExpenseDetails</Role>
      <ShortName>PROPERTY, PLANT AND EQUIPMENT, NET - Schedule of Depreciation Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNETAdditionalInformationDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9955553 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Components of Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNETScheduleofComponentsofIntangibleAssetsDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Components of Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9955554 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Amortization Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNETScheduleofAmortizationExpenseDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Amortization Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9955555 - Disclosure - GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Estimated Future Amortization Expense Related to Finite Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/GOODWILLANDINTANGIBLEASSETSNETScheduleofEstimatedFutureAmortizationExpenseRelatedtoFiniteIntangibleAssetsDetails</Role>
      <ShortName>GOODWILL AND INTANGIBLE ASSETS, NET - Schedule of Estimated Future Amortization Expense Related to Finite Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9955556 - Disclosure - LOAN AGREEMENTS - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LOANAGREEMENTSAdditionalInformationDetails</Role>
      <ShortName>LOAN AGREEMENTS - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9955557 - Disclosure - STOCKHOLDERS??? EQUITY - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKHOLDERSEQUITYAdditionalInformationDetails</Role>
      <ShortName>STOCKHOLDERS??? EQUITY - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9955558 - Disclosure - STOCKHOLDERS??? EQUITY- Schedule of Assumptions used in the Black-Sholes pricing model calculation for the Warrant issued (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKHOLDERSEQUITYScheduleofAssumptionsusedintheBlackSholespricingmodelcalculationfortheWarrantissuedDetails</Role>
      <ShortName>STOCKHOLDERS??? EQUITY- Schedule of Assumptions used in the Black-Sholes pricing model calculation for the Warrant issued (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9955559 - Disclosure - STOCK-BASED COMPENSATION - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATIONAdditionalInformationDetails</Role>
      <ShortName>STOCK-BASED COMPENSATION - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9955560 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Stock-based Compensation Recorded in Consolidated Statements of Operations and Comprehensive Loss (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATIONScheduleofStockbasedCompensationRecordedinConsolidatedStatementsofOperationsandComprehensiveLossDetails</Role>
      <ShortName>STOCK-BASED COMPENSATION - Schedule of Stock-based Compensation Recorded in Consolidated Statements of Operations and Comprehensive Loss (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9955561 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Stock Option Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATIONScheduleofStockOptionActivityDetails</Role>
      <ShortName>STOCK-BASED COMPENSATION - Schedule of Stock Option Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9955562 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Performance-based Restricted Stock Unit Activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/STOCKBASEDCOMPENSATIONScheduleofPerformancebasedRestrictedStockUnitActivityDetails</Role>
      <ShortName>STOCK-BASED COMPENSATION - Schedule of Performance-based Restricted Stock Unit Activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9955563 - Disclosure - EMPLOYEE BENEFITS - (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/EMPLOYEEBENEFITSDetails</Role>
      <ShortName>EMPLOYEE BENEFITS - (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/EMPLOYEEBENEFITS</ParentRole>
      <Position>86</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9955564 - Disclosure - Leases - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LeasesAdditionalInformationDetails</Role>
      <ShortName>Leases - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9955565 - Disclosure - Leases - Schedule of Supplemental Balance Sheet Information Related to Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LeasesScheduleofSupplementalBalanceSheetInformationRelatedtoLeasesDetails</Role>
      <ShortName>Leases - Schedule of Supplemental Balance Sheet Information Related to Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9955566 - Disclosure - Leases - Schedule of Components of Lease Expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LeasesScheduleofComponentsofLeaseExpenseDetails</Role>
      <ShortName>Leases - Schedule of Components of Lease Expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9955567 - Disclosure - Leases - Schedule of Supplemental Cash Flow Information Related To Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LeasesScheduleofSupplementalCashFlowInformationRelatedToLeasesDetails</Role>
      <ShortName>Leases - Schedule of Supplemental Cash Flow Information Related To Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9955568 - Disclosure - Leases - Schedule of The Future Minimum Operating Lease Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/LeasesScheduleofTheFutureMinimumOperatingLeasePaymentsDetails</Role>
      <ShortName>Leases - Schedule of The Future Minimum Operating Lease Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9955569 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/COMMITMENTSANDCONTINGENCIESDetails</Role>
      <ShortName>COMMITMENTS AND CONTINGENCIES (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/COMMITMENTSANDCONTINGENCIES</ParentRole>
      <Position>92</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9955570 - Disclosure - INCOME TAXES - Schedule of Pretax Loss from Domestic and Foreign Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofPretaxLossfromDomesticandForeignOperationsDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Pretax Loss from Domestic and Foreign Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9955571 - Disclosure - INCOME TAXES - Schedule of Provision (Benefit) for Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofProvisionBenefitforIncomeTaxesDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Provision (Benefit) for Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9955572 - Disclosure - INCOME TAXES - Schedule of Reconciliation Effective Tax Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofReconciliationEffectiveTaxRateDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Reconciliation Effective Tax Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>9955573 - Disclosure - INCOME TAXES - Schedule of Reconciliation Effective Tax Rate Before Adoption of ASU (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofReconciliationEffectiveTaxRateBeforeAdoptionofASUDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Reconciliation Effective Tax Rate Before Adoption of ASU (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>9955574 - Disclosure - INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofDeferredTaxAssetsandLiabilitiesDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>9955575 - Disclosure - INCOME TAXES - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESAdditionalInformationDetails</Role>
      <ShortName>INCOME TAXES - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>9955576 - Disclosure - INCOME TAXES - Schedule of Reconciliation of Beginning and Ending Amount Of Unrecognized Tax Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofReconciliationofBeginningandEndingAmountOfUnrecognizedTaxBenefitsDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Reconciliation of Beginning and Ending Amount Of Unrecognized Tax Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>9955577 - Disclosure - INCOME TAXES - Schedule of Income Taxes Paid By Jurisdiction (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/INCOMETAXESScheduleofIncomeTaxesPaidByJurisdictionDetails</Role>
      <ShortName>INCOME TAXES - Schedule of Income Taxes Paid By Jurisdiction (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>9955578 - Disclosure - NET LOSS PER SHARE - Schedule of Basic and Diluted net Loss Per Share Attributable to Common Stockholders (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/NETLOSSPERSHAREScheduleofBasicandDilutednetLossPerShareAttributabletoCommonStockholdersDetails</Role>
      <ShortName>NET LOSS PER SHARE - Schedule of Basic and Diluted net Loss Per Share Attributable to Common Stockholders (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>9955579 - Disclosure - NET LOSS PER SHARE - Schedule of Diluted Net Loss Per Share Attributable to Common Stockholders (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/NETLOSSPERSHAREScheduleofDilutedNetLossPerShareAttributabletoCommonStockholdersDetails</Role>
      <ShortName>NET LOSS PER SHARE - Schedule of Diluted Net Loss Per Share Attributable to Common Stockholders (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>9955580 - Disclosure - SEGMENTS - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SEGMENTSAdditionalInformationDetails</Role>
      <ShortName>SEGMENTS - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>9955581 - Disclosure - SEGMENTS - Schedule of Information by Reportable Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SEGMENTSScheduleofInformationbyReportableSegmentDetails</Role>
      <ShortName>SEGMENTS - Schedule of Information by Reportable Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>9955582 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Total Accounts Receivable Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATIONScheduleofTotalAccountsReceivableNetDetails</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Total Accounts Receivable Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>9955583 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Total Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATIONScheduleofTotalRevenueDetails</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Total Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>9955584 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Consolidated Net Revenue by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATIONScheduleofConsolidatedNetRevenuebyGeographicAreaDetails</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Consolidated Net Revenue by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>9955585 - Disclosure - CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Long Lived Assets by Geographic Area (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/CONCENTRATIONOFCREDITRISKSIGNIFICANTCUSTOMERSANDGEOGRAPHICINFORMATIONScheduleofLongLivedAssetsbyGeographicAreaDetails</Role>
      <ShortName>CONCENTRATION OF CREDIT RISK, SIGNIFICANT CUSTOMERS AND GEOGRAPHIC INFORMATION - Schedule of Long Lived Assets by Geographic Area (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>9955586 - Disclosure - RELATED PARTY TRANSACTIONS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/RELATEDPARTYTRANSACTIONSDetails</Role>
      <ShortName>RELATED PARTY TRANSACTIONS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/RELATEDPARTYTRANSACTIONS</ParentRole>
      <Position>109</Position>
    </Report>
    <Report instance="rklb-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>9955587 - Disclosure - SUBSEQUENT EVENTS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.rocketlabusa.com/role/SUBSEQUENTEVENTSDetails</Role>
      <ShortName>SUBSEQUENT EVENTS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.rocketlabusa.com/role/SUBSEQUENTEVENTS</ParentRole>
      <Position>110</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="rklb-20251231.htm">rklb-20251231.htm</File>
    <File>rklb-20251231.xsd</File>
    <File>rklb-20251231_cal.xml</File>
    <File>rklb-20251231_def.xml</File>
    <File>rklb-20251231_lab.xml</File>
    <File>rklb-20251231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>rklb-20251231_g1.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="1">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="1441">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="15">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="38">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="10">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
