<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>2756</ContextCount>
  <ElementCount>1095</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>351</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>8</UnitCount>
  <MyReports>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>1001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1002 - Statement - CONSOLIDATED BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1003 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>CONSOLIDATED BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1004 - Statement - CONSOLIDATED STATEMENTS OF INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedStatementsOfIncome</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1005 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedStatementsOfComprehensiveIncome</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1006 - Statement - CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedStatementsOfChangesInEquity</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1007 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>CONSOLIDATED STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="d29000d20f.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="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.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>9</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.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>10</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>999002 - Disclosure - Significant Accounting and Reporting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SignificantAccountingAndReportingPolicies</Role>
      <ShortName>Significant Accounting and Reporting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>999003 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>999004 - Disclosure - Acquisitions and Divestitures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AcquisitionsAndDivestitures</Role>
      <ShortName>Acquisitions and Divestitures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>999005 - Disclosure - Revenues from Contracts with Customers</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomers</Role>
      <ShortName>Revenues from Contracts with Customers</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>999006 - Disclosure - Cash Flow Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CashFlowInformation</Role>
      <ShortName>Cash Flow Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>999007 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/Leases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>999008 - Disclosure - Installment Loans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InstallmentLoans</Role>
      <ShortName>Installment Loans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>999009 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLosses</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>999010 - Disclosure - Investment in Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecurities</Role>
      <ShortName>Investment in Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>999011 - Disclosure - Transfer of Financial Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/TransferOfFinancialAssets</Role>
      <ShortName>Transfer of Financial Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>999012 - Disclosure - Variable Interest Entities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/VariableInterestEntities</Role>
      <ShortName>Variable Interest Entities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>999013 - Disclosure - Equity Method Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EquityMethodInvestments</Role>
      <ShortName>Equity Method Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>999014 - Disclosure - Goodwill and Other Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssets</Role>
      <ShortName>Goodwill and Other Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>999015 - Disclosure - Short-Term and Long-Term Debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebt</Role>
      <ShortName>Short-Term and Long-Term Debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>999016 - Disclosure - Deposits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/Deposits</Role>
      <ShortName>Deposits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>999017 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>999018 - Disclosure - Pension Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlans</Role>
      <ShortName>Pension Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>999019 - Disclosure - Redeemable Noncontrolling Interests</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RedeemableNoncontrollingInterests</Role>
      <ShortName>Redeemable Noncontrolling Interests</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>999020 - Disclosure - Stock-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/StockBasedCompensation</Role>
      <ShortName>Stock-Based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>999021 - Disclosure - Accumulated Other Comprehensive Income (Loss)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLoss</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>999022 - Disclosure - ORIX Corporation Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OrixCorporationShareholdersEquity</Role>
      <ShortName>ORIX Corporation Shareholders' Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>999023 - Disclosure - Gains on Investment Securities and Dividends</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GainsOnInvestmentSecuritiesAndDividends</Role>
      <ShortName>Gains on Investment Securities and Dividends</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>999024 - Disclosure - Income and Expenses Relating to Life Insurance Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperations</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>999025 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperations</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>999026 - Disclosure - Write-Downs of Long-Lived Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/WriteDownsOfLongLivedAssets</Role>
      <ShortName>Write-Downs of Long-Lived Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>999027 - Disclosure - Per Share Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PerShareData</Role>
      <ShortName>Per Share Data</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>999028 - Disclosure - Derivative Financial Instruments and Hedging</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedging</Role>
      <ShortName>Derivative Financial Instruments and Hedging</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>999029 - Disclosure - Offsetting Assets and Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OffsettingAssetsAndLiabilities</Role>
      <ShortName>Offsetting Assets and Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>999030 - Disclosure - Significant Concentrations of Credit Risk</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SignificantConcentrationsOfCreditRisk</Role>
      <ShortName>Significant Concentrations of Credit Risk</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>999031 - Disclosure - Estimated Fair Value of Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstruments</Role>
      <ShortName>Estimated Fair Value of Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>999032 - Disclosure - Commitments, Guarantees and Contingent Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilities</Role>
      <ShortName>Commitments, Guarantees and Contingent Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>999033 - Disclosure - Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformation</Role>
      <ShortName>Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>999034 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>999035 - Disclosure - Schedule II.&amp;#8212;Valuation and Qualifying Accounts and Reserves ORIX Corporation and Subsidiaries</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ScheduleIiValuationAndQualifyingAccountsAndReservesOrixCorporationAndSubsidiaries</Role>
      <ShortName>Schedule II.&amp;#8212;Valuation and Qualifying Accounts and Reserves ORIX Corporation and Subsidiaries</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>999036 - Disclosure - Significant Accounting and Reporting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SignificantAccountingAndReportingPoliciesPolicies</Role>
      <ShortName>Significant Accounting and Reporting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SignificantAccountingAndReportingPolicies</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>999037 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurements</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>999038 - Disclosure - Revenues from Contracts with Customers (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomersTables</Role>
      <ShortName>Revenues from Contracts with Customers (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/RevenuesFromContractsWithCustomers</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>999039 - Disclosure - Cash Flow Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CashFlowInformationTables</Role>
      <ShortName>Cash Flow Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/CashFlowInformation</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>999040 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/Leases</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>999041 - Disclosure - Installment Loans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InstallmentLoansTables</Role>
      <ShortName>Installment Loans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InstallmentLoans</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>999042 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesTables</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLosses</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>999043 - Disclosure - Investment in Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesTables</Role>
      <ShortName>Investment in Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecurities</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>999044 - Disclosure - Transfer of Financial Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/TransferOfFinancialAssetsTables</Role>
      <ShortName>Transfer of Financial Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/TransferOfFinancialAssets</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>999045 - Disclosure - Variable Interest Entities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/VariableInterestEntitiesTables</Role>
      <ShortName>Variable Interest Entities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/VariableInterestEntities</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>999046 - Disclosure - Equity Method Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EquityMethodInvestmentsTables</Role>
      <ShortName>Equity Method Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EquityMethodInvestments</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>999047 - Disclosure - Goodwill and Other Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Other Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssets</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>999048 - Disclosure - Short-Term and Long-Term Debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtTables</Role>
      <ShortName>Short-Term and Long-Term Debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/ShortTermAndLongTermDebt</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>999049 - Disclosure - Deposits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DepositsTables</Role>
      <ShortName>Deposits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/Deposits</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>999050 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxes</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>999051 - Disclosure - Pension Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansTables</Role>
      <ShortName>Pension Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlans</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>999052 - Disclosure - Redeemable Noncontrolling Interests (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RedeemableNoncontrollingInterestsTables</Role>
      <ShortName>Redeemable Noncontrolling Interests (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/RedeemableNoncontrollingInterests</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>999053 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossTables</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLoss</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>999054 - Disclosure - ORIX Corporation Shareholders' Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OrixCorporationShareholdersEquityTables</Role>
      <ShortName>ORIX Corporation Shareholders' Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/OrixCorporationShareholdersEquity</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>999055 - Disclosure - Gains on Investment Securities and Dividends (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GainsOnInvestmentSecuritiesAndDividendsTables</Role>
      <ShortName>Gains on Investment Securities and Dividends (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/GainsOnInvestmentSecuritiesAndDividends</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>999056 - Disclosure - Income and Expenses Relating to Life Insurance Operations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperationsTables</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperations</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>999057 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsTables</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperations</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>999058 - Disclosure - Write-Downs of Long-Lived Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/WriteDownsOfLongLivedAssetsTables</Role>
      <ShortName>Write-Downs of Long-Lived Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/WriteDownsOfLongLivedAssets</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>999059 - Disclosure - Per Share Data (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PerShareDataTables</Role>
      <ShortName>Per Share Data (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PerShareData</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>999060 - Disclosure - Derivative Financial Instruments and Hedging (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedging</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>999061 - Disclosure - Offsetting Assets and Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OffsettingAssetsAndLiabilitiesTables</Role>
      <ShortName>Offsetting Assets and Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/OffsettingAssetsAndLiabilities</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>999062 - Disclosure - Estimated Fair Value of Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstrumentsTables</Role>
      <ShortName>Estimated Fair Value of Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstruments</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>999063 - Disclosure - Commitments, Guarantees and Contingent Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilitiesTables</Role>
      <ShortName>Commitments, Guarantees and Contingent Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilities</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>999064 - Disclosure - Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationTables</Role>
      <ShortName>Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformation</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>999065 - Disclosure - Significant Accounting and Reporting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SignificantAccountingAndReportingPoliciesAdditionalInformationDetail</Role>
      <ShortName>Significant Accounting and Reporting Policies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>999066 - Disclosure - Fair Value Measurements (Recorded Amounts of Major Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsRecordedAmountsOfMajorFinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetail</Role>
      <ShortName>Fair Value Measurements (Recorded Amounts of Major Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>999067 - Disclosure - Fair Value Measurements (Recorded Amounts of Major Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsRecordedAmountsOfMajorFinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisParentheticalDetail</Role>
      <ShortName>Fair Value Measurements (Recorded Amounts of Major Financial Assets and Liabilities Measured at Fair Value on Recurring Basis) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>999068 - Disclosure - Fair Value Measurements (Reconciliation of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsReconciliationOfFinancialAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisUsingSignificantUnobservableInputsDetail</Role>
      <ShortName>Fair Value Measurements (Reconciliation of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>999069 - Disclosure - Fair Value Measurements - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsAdditionalInformationDetail</Role>
      <ShortName>Fair Value Measurements - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>999070 - Disclosure - Fair Value Measurements (Recorded Amounts of Major Assets Measured at Fair Value on Nonrecurring Basis) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsRecordedAmountsOfMajorAssetsMeasuredAtFairValueOnNonrecurringBasisDetail</Role>
      <ShortName>Fair Value Measurements (Recorded Amounts of Major Assets Measured at Fair Value on Nonrecurring Basis) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>999071 - Disclosure - Fair Value Measurements (Information about Valuation Techniques and Significant Unobservable Inputs Used in Valuation of Level Three Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsInformationAboutValuationTechniquesAndSignificantUnobservableInputsUsedInValuationOfLevelThreeAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetail</Role>
      <ShortName>Fair Value Measurements (Information about Valuation Techniques and Significant Unobservable Inputs Used in Valuation of Level Three Assets and Liabilities Measured at Fair Value on Recurring Basis) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>80</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>999072 - Disclosure - Fair Value Measurements (Information about Valuation Techniques and Significant Unobservable Inputs Used in Valuation of Level Three Assets Measured at Fair Value on Nonrecurring Basis) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/FairValueMeasurementsInformationAboutValuationTechniquesAndSignificantUnobservableInputsUsedInValuationOfLevelThreeAssetsMeasuredAtFairValueOnNonrecurringBasisDetail</Role>
      <ShortName>Fair Value Measurements (Information about Valuation Techniques and Significant Unobservable Inputs Used in Valuation of Level Three Assets Measured at Fair Value on Nonrecurring Basis) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/FairValueMeasurementsTables</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>999073 - Disclosure - Acquisitions and Divestitures - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AcquisitionsAndDivestituresAdditionalInformationDetail</Role>
      <ShortName>Acquisitions and Divestitures - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>999074 - Disclosure - Revenues from Contracts with Customers - Summary of Revenues from Contracts with Customers, and Other Sources of Revenue (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomersSummaryOfRevenuesFromContractsWithCustomersAndOtherSourcesOfRevenueDetail</Role>
      <ShortName>Revenues from Contracts with Customers - Summary of Revenues from Contracts with Customers, and Other Sources of Revenue (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>999075 - Disclosure - Revenues from Contracts with Customers - Summary of Costs of Goods and Real Estate Sold and Service Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomersSummaryOfCostsOfGoodsAndRealEstateSoldAndServiceExpenseDetail</Role>
      <ShortName>Revenues from Contracts with Customers - Summary of Costs of Goods and Real Estate Sold and Service Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>84</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>999076 - Disclosure - Revenues from Contracts with Customers - Balances from Contracts with Customers in Fee Business (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomersBalancesFromContractsWithCustomersInFeeBusinessDetail</Role>
      <ShortName>Revenues from Contracts with Customers - Balances from Contracts with Customers in Fee Business (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>999077 - Disclosure - Revenues from Contracts with Customers - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RevenuesFromContractsWithCustomersAdditionalInformationDetail</Role>
      <ShortName>Revenues from Contracts with Customers - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>999079 - Disclosure - Cash Flow Information - Summary of Cash, Cash Equivalents and Restricted Cash (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CashFlowInformationSummaryOfCashCashEquivalentsAndRestrictedCashDetail</Role>
      <ShortName>Cash Flow Information - Summary of Cash, Cash Equivalents and Restricted Cash (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>999080 - Disclosure - Cash Flow Information (Cash Payments) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CashFlowInformationCashPaymentsDetail</Role>
      <ShortName>Cash Flow Information (Cash Payments) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/CashFlowInformationTables</ParentRole>
      <Position>88</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>999081 - Disclosure - Cash Flow Information - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CashFlowInformationAdditionalInformationDetail</Role>
      <ShortName>Cash Flow Information - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>999082 - Disclosure - Leases - Lessor: Lease Income (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorLeaseIncomeDetail</Role>
      <ShortName>Leases - Lessor: Lease Income (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>999083 - Disclosure - Leases - Lessor: Lease Income (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorLeaseIncomeParentheticalDetail</Role>
      <ShortName>Leases - Lessor: Lease Income (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>999084 - Disclosure - Leases - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesAdditionalInformationDetail</Role>
      <ShortName>Leases - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>999085 - Disclosure - Leases - Lessor: Net Investment in Leases (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorNetInvestmentInLeasesDetail</Role>
      <ShortName>Leases - Lessor: Net Investment in Leases (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>999086 - Disclosure - Leases - Lessor: Net Investment in Leases (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorNetInvestmentInLeasesParentheticalDetail</Role>
      <ShortName>Leases - Lessor: Net Investment in Leases (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>999087 - Disclosure - Leases - Lessor: Investment in Operating Leases (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorInvestmentInOperatingLeasesDetail</Role>
      <ShortName>Leases - Lessor: Investment in Operating Leases (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>999088 - Disclosure - Leases - Lessor: Depreciation and Various Expenses Included in Costs of Operating Leases (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorDepreciationAndVariousExpensesIncludedInCostsOfOperatingLeasesDetail</Role>
      <ShortName>Leases - Lessor: Depreciation and Various Expenses Included in Costs of Operating Leases (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>999089 - Disclosure - Leases - Lessor: Amounts of Remaining Lease Receivables of Net Investment in Leases and Opearting Lease Contracts Due in Each of Next Five Years and Thereafter (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLessorAmountsOfRemainingLeaseReceivablesOfNetInvestmentInLeasesAndOpeartingLeaseContractsDueInEachOfNextFiveYearsAndThereafterDetail</Role>
      <ShortName>Leases - Lessor: Amounts of Remaining Lease Receivables of Net Investment in Leases and Opearting Lease Contracts Due in Each of Next Five Years and Thereafter (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>999090 - Disclosure - Leases - Lessee: Component of Lease Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLesseeComponentOfLeaseExpenseDetail</Role>
      <ShortName>Leases - Lessee: Component of Lease Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>999091 - Disclosure - Leases - Lessee: Supplemental Cash Flow Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLesseeSupplementalCashFlowInformationDetail</Role>
      <ShortName>Leases - Lessee: Supplemental Cash Flow Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>99</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>999092 - Disclosure - Leases - Lessee: Supplemental Balance Sheet Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLesseeSupplementalBalanceSheetInformationDetail</Role>
      <ShortName>Leases - Lessee: Supplemental Balance Sheet Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>999093 - Disclosure - Leases - Lessee: Amounts of Lease Liabilities Due in Each of Next Five Years and Thereafter (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LeasesLesseeAmountsOfLeaseLiabilitiesDueInEachOfNextFiveYearsAndThereafterDetail</Role>
      <ShortName>Leases - Lessee: Amounts of Lease Liabilities Due in Each of Next Five Years and Thereafter (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>999094 - Disclosure - Installment Loans (Composition of Installment Loans By Domicile and Type of Borrower) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InstallmentLoansCompositionOfInstallmentLoansByDomicileAndTypeOfBorrowerDetail</Role>
      <ShortName>Installment Loans (Composition of Installment Loans By Domicile and Type of Borrower) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InstallmentLoansTables</ParentRole>
      <Position>102</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>999095 - Disclosure - Installment Loans (Contractual Maturities of Installment Loans Except Purchased Loans) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InstallmentLoansContractualMaturitiesOfInstallmentLoansExceptPurchasedLoansDetail</Role>
      <ShortName>Installment Loans (Contractual Maturities of Installment Loans Except Purchased Loans) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InstallmentLoansTables</ParentRole>
      <Position>103</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>999096 - Disclosure - Installment Loans - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InstallmentLoansAdditionalInformationDetail</Role>
      <ShortName>Installment Loans - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>999097 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Allowance for Credit Losses for Installment Loans (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfAllowanceForCreditLossesForInstallmentLoansDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Allowance for Credit Losses for Installment Loans (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>999098 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Allowance for Credit Losses for Installment Loans (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfAllowanceForCreditLossesForInstallmentLoansParentheticalDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Allowance for Credit Losses for Installment Loans (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>999099 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Disclosure In Tabular Form Of Allowances For Credit Losses And Provision For Credit Losses (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfDisclosureInTabularFormOfAllowancesForCreditLossesAndProvisionForCreditLossesDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Disclosure In Tabular Form Of Allowances For Credit Losses And Provision For Credit Losses (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>999100 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Disclosure In Tabular Form Of Allowances For Credit Losses And Provision For Credit Losses (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfDisclosureInTabularFormOfAllowancesForCreditLossesAndProvisionForCreditLossesParentheticalDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Disclosure In Tabular Form Of Allowances For Credit Losses And Provision For Credit Losses (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>999101 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Purchased Loans (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfPurchasedLoansDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Purchased Loans (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>999102 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Origination Years of Financial Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfOriginationYearsOfFinancialAssetsDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Origination Years of Financial Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>999103 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Revolving Repayment Card Loans (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfRevolvingRepaymentCardLoansDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Revolving Repayment Card Loans (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>999104 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Past-Due Financial Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfPastDueFinancialAssetsDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Past-Due Financial Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>999105 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Non-Accrual of Financial Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfNonAccrualOfFinancialAssetsDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Non-Accrual of Financial Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>999106 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Modifications of Financing Receivables (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfModificationsOfFinancingReceivablesDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Modifications of Financing Receivables (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>999107 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Financial Effect of Modifications of Financing Receivable (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfFinancialEffectOfModificationsOfFinancingReceivableDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Financial Effect of Modifications of Financing Receivable (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>999108 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Financing Receivables Payment Default and Modifications of Past Due (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfFinancingReceivablesPaymentDefaultAndModificationsOfPastDueDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Financing Receivables Payment Default and Modifications of Past Due (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>116</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>999109 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Past Due Financial Assets Modified to Debtors (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesSummaryOfPastDueFinancialAssetsModifiedToDebtorsDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Summary of Past Due Financial Assets Modified to Debtors (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>117</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>999110 - Disclosure - Credit Quality of Financial Assets and the Allowance for Credit Losses - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CreditQualityOfFinancialAssetsAndTheAllowanceForCreditLossesAdditionalInformationDetail</Role>
      <ShortName>Credit Quality of Financial Assets and the Allowance for Credit Losses - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>118</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>999111 - Disclosure - Investment in Securities (Summary of Investment in Securities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesSummaryOfInvestmentInSecuritiesDetail</Role>
      <ShortName>Investment in Securities (Summary of Investment in Securities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>119</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>999112 - Disclosure - Investment in Securities (Summary of Investment in Securities) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesSummaryOfInvestmentInSecuritiesParentheticalDetail</Role>
      <ShortName>Investment in Securities (Summary of Investment in Securities) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>120</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>999113 - Disclosure - Investment in Securities - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesAdditionalInformationDetail</Role>
      <ShortName>Investment in Securities - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>121</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>999114 - Disclosure - Investment in Securities (Information About Impairment and Upward or Downward Adjustments Resulting From Observable Price Changes) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesInformationAboutImpairmentAndUpwardOrDownwardAdjustmentsResultingFromObservablePriceChangesDetail</Role>
      <ShortName>Investment in Securities (Information About Impairment and Upward or Downward Adjustments Resulting From Observable Price Changes) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>122</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>999115 - Disclosure - Investment in Securities (Amortized Cost Basis Amounts, Gross Unrealized Holding Gains, Gross Unrealized Holding Losses and Fair Values of Available-for-Sale Securities and Held-to-Maturity Securities in Each Major Security Type) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesAmortizedCostBasisAmountsGrossUnrealizedHoldingGainsGrossUnrealizedHoldingLossesAndFairValuesOfAvailableForSaleSecuritiesAndHeldToMaturitySecuritiesInEachMajorSecurityTypeDetail</Role>
      <ShortName>Investment in Securities (Amortized Cost Basis Amounts, Gross Unrealized Holding Gains, Gross Unrealized Holding Losses and Fair Values of Available-for-Sale Securities and Held-to-Maturity Securities in Each Major Security Type) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>123</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>999116 - Disclosure - Investment in Securities (Summary of Roll-forwards of Allowance for Credit Losses) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesSummaryOfRollForwardsOfAllowanceForCreditLossesDetail</Role>
      <ShortName>Investment in Securities (Summary of Roll-forwards of Allowance for Credit Losses) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>124</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>999117 - Disclosure - Investment in Securities (Information about Available-for-Sale and Held-to-Maturity Securities with Gross Unrealized Losses and Length of Time that Individual Securities Have Been in Continuous Unrealized Loss Position) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesInformationAboutAvailableForSaleAndHeldToMaturitySecuritiesWithGrossUnrealizedLossesAndLengthOfTimeThatIndividualSecuritiesHaveBeenInContinuousUnrealizedLossPositionDetail</Role>
      <ShortName>Investment in Securities (Information about Available-for-Sale and Held-to-Maturity Securities with Gross Unrealized Losses and Length of Time that Individual Securities Have Been in Continuous Unrealized Loss Position) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>125</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>999118 - Disclosure - Investment in Securities (Summary of Contractual Maturities of Available-for-Sale Debt Securities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/InvestmentInSecuritiesSummaryOfContractualMaturitiesOfAvailableForSaleDebtSecuritiesDetail</Role>
      <ShortName>Investment in Securities (Summary of Contractual Maturities of Available-for-Sale Debt Securities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/InvestmentInSecuritiesTables</ParentRole>
      <Position>126</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>999119 - Disclosure - Transfer of Financial Assets - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/TransferOfFinancialAssetsAdditionalInformationDetail</Role>
      <ShortName>Transfer of Financial Assets - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>127</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>999120 - Disclosure - Transfer of Financial Assets - Roll-Forwards of Amount of Servicing Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/TransferOfFinancialAssetsRollForwardsOfAmountOfServicingAssetsDetail</Role>
      <ShortName>Transfer of Financial Assets - Roll-Forwards of Amount of Servicing Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>128</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R129.htm</HtmlFileName>
      <LongName>999121 - Disclosure - Transfer of Financial Assets - Fair Value of Servicing Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/TransferOfFinancialAssetsFairValueOfServicingAssetsDetail</Role>
      <ShortName>Transfer of Financial Assets - Fair Value of Servicing Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>129</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R130.htm</HtmlFileName>
      <LongName>999122 - Disclosure - Variable Interest Entities (Information about Consolidated VIEs) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/VariableInterestEntitiesInformationAboutConsolidatedViesDetail</Role>
      <ShortName>Variable Interest Entities (Information about Consolidated VIEs) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/VariableInterestEntitiesTables</ParentRole>
      <Position>130</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R131.htm</HtmlFileName>
      <LongName>999123 - Disclosure - Variable Interest Entities (Information about Non-consolidated VIEs) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/VariableInterestEntitiesInformationAboutNonConsolidatedViesDetail</Role>
      <ShortName>Variable Interest Entities (Information about Non-consolidated VIEs) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/VariableInterestEntitiesTables</ParentRole>
      <Position>131</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>999124 - Disclosure - Equity Method Investments (Summary of Equity Method Investments) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EquityMethodInvestmentsSummaryOfEquityMethodInvestmentsDetail</Role>
      <ShortName>Equity Method Investments (Summary of Equity Method Investments) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EquityMethodInvestmentsTables</ParentRole>
      <Position>132</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>999125 - Disclosure - Equity Method Investments - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EquityMethodInvestmentsAdditionalInformationDetail</Role>
      <ShortName>Equity Method Investments - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>133</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>999126 - Disclosure - Equity Method Investments (Summary of Information Relating to The Equity Method Investees) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EquityMethodInvestmentsSummaryOfInformationRelatingToTheEquityMethodInvesteesDetail</Role>
      <ShortName>Equity Method Investments (Summary of Information Relating to The Equity Method Investees) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EquityMethodInvestmentsTables</ParentRole>
      <Position>134</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R135.htm</HtmlFileName>
      <LongName>999127 - Disclosure - Goodwill and Other Intangible Assets (Changes in Goodwill by Reportable Segment) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsChangesInGoodwillByReportableSegmentDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets (Changes in Goodwill by Reportable Segment) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsTables</ParentRole>
      <Position>135</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R136.htm</HtmlFileName>
      <LongName>999128 - Disclosure - Goodwill and Other Intangible Assets - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsAdditionalInformationDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>136</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R137.htm</HtmlFileName>
      <LongName>999129 - Disclosure - Goodwill and Other Intangible Assets (Other Intangible Assets) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsOtherIntangibleAssetsDetail</Role>
      <ShortName>Goodwill and Other Intangible Assets (Other Intangible Assets) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/GoodwillAndOtherIntangibleAssetsTables</ParentRole>
      <Position>137</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R138.htm</HtmlFileName>
      <LongName>999130 - Disclosure - Short-Term and Long-Term Debt (Composition of Short-Term Debt and Weighted Average Contract Interest Rate on Short-Term Debt) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtCompositionOfShortTermDebtAndWeightedAverageContractInterestRateOnShortTermDebtDetail</Role>
      <ShortName>Short-Term and Long-Term Debt (Composition of Short-Term Debt and Weighted Average Contract Interest Rate on Short-Term Debt) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/ShortTermAndLongTermDebtTables</ParentRole>
      <Position>138</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>999131 - Disclosure - Short-Term and Long-Term Debt (Composition of Long-Term Debt, Weighted Average Contract Interest Rate on Long-Term Debt and Repayment Due Dates) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtCompositionOfLongTermDebtWeightedAverageContractInterestRateOnLongTermDebtAndRepaymentDueDatesDetail</Role>
      <ShortName>Short-Term and Long-Term Debt (Composition of Long-Term Debt, Weighted Average Contract Interest Rate on Long-Term Debt and Repayment Due Dates) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/ShortTermAndLongTermDebtTables</ParentRole>
      <Position>139</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R140.htm</HtmlFileName>
      <LongName>999132 - Disclosure - Short-Term and Long-Term Debt (Repayment Schedule for Next Five Years and Thereafter for Long-Term Debt) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtRepaymentScheduleForNextFiveYearsAndThereafterForLongTermDebtDetail</Role>
      <ShortName>Short-Term and Long-Term Debt (Repayment Schedule for Next Five Years and Thereafter for Long-Term Debt) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/ShortTermAndLongTermDebtTables</ParentRole>
      <Position>140</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R141.htm</HtmlFileName>
      <LongName>999133 - Disclosure - Short-Term and Long-Term Debt - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtAdditionalInformationDetail</Role>
      <ShortName>Short-Term and Long-Term Debt - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>141</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R142.htm</HtmlFileName>
      <LongName>999134 - Disclosure - Short-Term and Long-Term Debt (Assets Provided as Collateral for Short-Term and Long-Term Debt Payables to Financial Institutions) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ShortTermAndLongTermDebtAssetsProvidedAsCollateralForShortTermAndLongTermDebtPayablesToFinancialInstitutionsDetail</Role>
      <ShortName>Short-Term and Long-Term Debt (Assets Provided as Collateral for Short-Term and Long-Term Debt Payables to Financial Institutions) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/ShortTermAndLongTermDebtTables</ParentRole>
      <Position>142</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R143.htm</HtmlFileName>
      <LongName>999135 - Disclosure - Deposits (Summary of Deposits) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DepositsSummaryOfDepositsDetail</Role>
      <ShortName>Deposits (Summary of Deposits) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DepositsTables</ParentRole>
      <Position>143</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R144.htm</HtmlFileName>
      <LongName>999136 - Disclosure - Deposits - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DepositsAdditionalInformationDetail</Role>
      <ShortName>Deposits - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>144</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>999137 - Disclosure - Deposits (Maturity Schedule of Time Deposits) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DepositsMaturityScheduleOfTimeDepositsDetail</Role>
      <ShortName>Deposits (Maturity Schedule of Time Deposits) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DepositsTables</ParentRole>
      <Position>145</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R146.htm</HtmlFileName>
      <LongName>999138 - Disclosure - Income Taxes - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesAdditionalInformationDetail</Role>
      <ShortName>Income Taxes - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>146</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R147.htm</HtmlFileName>
      <LongName>999139 - Disclosure - Income Taxes (Income before Income Taxes and Provision for Income Taxes) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesIncomeBeforeIncomeTaxesAndProvisionForIncomeTaxesDetail</Role>
      <ShortName>Income Taxes (Income before Income Taxes and Provision for Income Taxes) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>147</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R148.htm</HtmlFileName>
      <LongName>999140 - Disclosure - Income Taxes (Reconciliations of Differences between Tax Provision Computed at Statutory Rate and Consolidated Provision for Income Taxes) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesReconciliationsOfDifferencesBetweenTaxProvisionComputedAtStatutoryRateAndConsolidatedProvisionForIncomeTaxesDetail</Role>
      <ShortName>Income Taxes (Reconciliations of Differences between Tax Provision Computed at Statutory Rate and Consolidated Provision for Income Taxes) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>148</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R149.htm</HtmlFileName>
      <LongName>999141 - Disclosure - Income Taxes (Summary of Amounts of Taxes Paid (Net of Amounts Received)) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesSummaryOfAmountsOfTaxesPaidNetOfAmountsReceivedDetail</Role>
      <ShortName>Income Taxes (Summary of Amounts of Taxes Paid (Net of Amounts Received)) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>149</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R150.htm</HtmlFileName>
      <LongName>999142 - Disclosure - Income Taxes (Total Income Tax Expense Recognized) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesTotalIncomeTaxExpenseRecognizedDetail</Role>
      <ShortName>Income Taxes (Total Income Tax Expense Recognized) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>150</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R151.htm</HtmlFileName>
      <LongName>999143 - Disclosure - Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesTaxEffectsOfTemporaryDifferencesAndCarryforwardsGivingRiseToDeferredTaxAssetsAndLiabilitiesDetail</Role>
      <ShortName>Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>151</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R152.htm</HtmlFileName>
      <LongName>999144 - Disclosure - Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesTaxEffectsOfTemporaryDifferencesAndCarryforwardsGivingRiseToDeferredTaxAssetsAndLiabilitiesParentheticalDetail</Role>
      <ShortName>Income Taxes (Tax Effects of Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>152</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R153.htm</HtmlFileName>
      <LongName>999145 - Disclosure - Income Taxes (Captions of Net Deferred Tax Assets and Liabilities Reflected in Consolidated Balance Sheets) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesCaptionsOfNetDeferredTaxAssetsAndLiabilitiesReflectedInConsolidatedBalanceSheetsDetail</Role>
      <ShortName>Income Taxes (Captions of Net Deferred Tax Assets and Liabilities Reflected in Consolidated Balance Sheets) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>153</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R154.htm</HtmlFileName>
      <LongName>999146 - Disclosure - Income Taxes (Expiry Schedule of Net Operating Loss Carryforwards) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeTaxesExpiryScheduleOfNetOperatingLossCarryforwardsDetail</Role>
      <ShortName>Income Taxes (Expiry Schedule of Net Operating Loss Carryforwards) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/IncomeTaxesTables</ParentRole>
      <Position>154</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R155.htm</HtmlFileName>
      <LongName>999147 - Disclosure - Pension Plans (Funded Status of Defined Benefit Pension Plans) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansFundedStatusOfDefinedBenefitPensionPlansDetail</Role>
      <ShortName>Pension Plans (Funded Status of Defined Benefit Pension Plans) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>155</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R156.htm</HtmlFileName>
      <LongName>999148 - Disclosure - Pension Plans (Defined Benefit Plan Amount Recognized in Accumulated Other Comprehensive Income (Loss), Pre-tax) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansDefinedBenefitPlanAmountRecognizedInAccumulatedOtherComprehensiveIncomeLossPreTaxDetail</Role>
      <ShortName>Pension Plans (Defined Benefit Plan Amount Recognized in Accumulated Other Comprehensive Income (Loss), Pre-tax) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>156</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R157.htm</HtmlFileName>
      <LongName>999149 - Disclosure - Pension Plans (Summary of Accumulated Benefit Obligations and Fair Value of Plan Assets for Pension Plans) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansSummaryOfAccumulatedBenefitObligationsAndFairValueOfPlanAssetsForPensionPlansDetail</Role>
      <ShortName>Pension Plans (Summary of Accumulated Benefit Obligations and Fair Value of Plan Assets for Pension Plans) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>157</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R158.htm</HtmlFileName>
      <LongName>999150 - Disclosure - Pension Plans (Summary of Projected Benefit Obligations and Fair Value of Plan Assets for Pension Plans) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansSummaryOfProjectedBenefitObligationsAndFairValueOfPlanAssetsForPensionPlansDetail</Role>
      <ShortName>Pension Plans (Summary of Projected Benefit Obligations and Fair Value of Plan Assets for Pension Plans) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>158</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R159.htm</HtmlFileName>
      <LongName>999151 - Disclosure - Pension Plans - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansAdditionalInformationDetail</Role>
      <ShortName>Pension Plans - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>159</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R160.htm</HtmlFileName>
      <LongName>999152 - Disclosure - Pension Plans (Net Pension Cost of Defined Benefit Plans) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansNetPensionCostOfDefinedBenefitPlansDetail</Role>
      <ShortName>Pension Plans (Net Pension Cost of Defined Benefit Plans) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>160</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R161.htm</HtmlFileName>
      <LongName>999153 - Disclosure - Pension Plans (Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansOtherChangesInPlanAssetsAndBenefitObligationsRecognizedInOtherComprehensiveIncomeLossDetail</Role>
      <ShortName>Pension Plans (Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income (Loss) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>161</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R162.htm</HtmlFileName>
      <LongName>999154 - Disclosure - Pension Plans (Significant Assumptions of Japan and Overseas Pension Plans Used to Determine Plan Amounts) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansSignificantAssumptionsOfJapanAndOverseasPensionPlansUsedToDeterminePlanAmountsDetail</Role>
      <ShortName>Pension Plans (Significant Assumptions of Japan and Overseas Pension Plans Used to Determine Plan Amounts) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>162</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R163.htm</HtmlFileName>
      <LongName>999155 - Disclosure - Pension Plans (Fair Value of Pension Plan Assets by Asset Category) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansFairValueOfPensionPlanAssetsByAssetCategoryDetail</Role>
      <ShortName>Pension Plans (Fair Value of Pension Plan Assets by Asset Category) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>163</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R164.htm</HtmlFileName>
      <LongName>999156 - Disclosure - Pension Plans (Fair Value of Pension Plan Assets by Asset Category) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansFairValueOfPensionPlanAssetsByAssetCategoryParentheticalDetail</Role>
      <ShortName>Pension Plans (Fair Value of Pension Plan Assets by Asset Category) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>164</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R165.htm</HtmlFileName>
      <LongName>999157 - Disclosure - Pension Plans (Benefits Expected to be Paid) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PensionPlansBenefitsExpectedToBePaidDetail</Role>
      <ShortName>Pension Plans (Benefits Expected to be Paid) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PensionPlansTables</ParentRole>
      <Position>165</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R166.htm</HtmlFileName>
      <LongName>999158 - Disclosure - Redeemable Noncontrolling Interests (Changes in Redeemable Noncontrolling Interests) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/RedeemableNoncontrollingInterestsChangesInRedeemableNoncontrollingInterestsDetail</Role>
      <ShortName>Redeemable Noncontrolling Interests (Changes in Redeemable Noncontrolling Interests) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/RedeemableNoncontrollingInterestsTables</ParentRole>
      <Position>166</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R167.htm</HtmlFileName>
      <LongName>999159 - Disclosure - Stock-Based Compensation - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/StockBasedCompensationAdditionalInformationDetail</Role>
      <ShortName>Stock-Based Compensation - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>167</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R168.htm</HtmlFileName>
      <LongName>999160 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Changes in Components of Accumulated Other Comprehensive Income (Loss)) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossChangesInComponentsOfAccumulatedOtherComprehensiveIncomeLossDetail</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) (Changes in Components of Accumulated Other Comprehensive Income (Loss)) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossTables</ParentRole>
      <Position>168</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R169.htm</HtmlFileName>
      <LongName>999161 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Changes in Components of Accumulated Other Comprehensive Income (Loss)) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossChangesInComponentsOfAccumulatedOtherComprehensiveIncomeLossParentheticalDetail</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) (Changes in Components of Accumulated Other Comprehensive Income (Loss)) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossTables</ParentRole>
      <Position>169</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R170.htm</HtmlFileName>
      <LongName>999162 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Amounts Reclassified to Net Income from Accumulated Other Comprehensive Income (loss)) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossAmountsReclassifiedToNetIncomeFromAccumulatedOtherComprehensiveIncomeLossDetail</Role>
      <ShortName>Accumulated Other Comprehensive Income (Loss) (Amounts Reclassified to Net Income from Accumulated Other Comprehensive Income (loss)) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/AccumulatedOtherComprehensiveIncomeLossTables</ParentRole>
      <Position>170</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R171.htm</HtmlFileName>
      <LongName>999163 - Disclosure - ORIX Corporation Shareholders' Equity (Changes in Number of Shares Issued) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OrixCorporationShareholdersEquityChangesInNumberOfSharesIssuedDetail</Role>
      <ShortName>ORIX Corporation Shareholders' Equity (Changes in Number of Shares Issued) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/OrixCorporationShareholdersEquityTables</ParentRole>
      <Position>171</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R172.htm</HtmlFileName>
      <LongName>999164 - Disclosure - ORIX Corporation Shareholders' Equity - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OrixCorporationShareholdersEquityAdditionalInformationDetail</Role>
      <ShortName>ORIX Corporation Shareholders' Equity - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>172</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R173.htm</HtmlFileName>
      <LongName>999165 - Disclosure - Gains on Investment Securities and Dividends - Gains on Investment Securities and Dividends (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/GainsOnInvestmentSecuritiesAndDividendsGainsOnInvestmentSecuritiesAndDividendsDetail</Role>
      <ShortName>Gains on Investment Securities and Dividends - Gains on Investment Securities and Dividends (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>173</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R174.htm</HtmlFileName>
      <LongName>999166 - Disclosure - Income and Expenses Relating to Life Insurance Operations - Life Insurance Premiums and Related Investment Income (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperationsLifeInsurancePremiumsAndRelatedInvestmentIncomeDetail</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations - Life Insurance Premiums and Related Investment Income (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>174</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R175.htm</HtmlFileName>
      <LongName>999167 - Disclosure - Income and Expenses Relating to Life Insurance Operations - Life Insurance Premiums and Related Investment Income (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperationsLifeInsurancePremiumsAndRelatedInvestmentIncomeParentheticalDetail</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations - Life Insurance Premiums and Related Investment Income (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>175</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R176.htm</HtmlFileName>
      <LongName>999168 - Disclosure - Income and Expenses Relating to Life Insurance Operations - Reinsurance Benefits and Reinsurance Premiums Included in Life Insurance Premiums (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperationsReinsuranceBenefitsAndReinsurancePremiumsIncludedInLifeInsurancePremiumsDetail</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations - Reinsurance Benefits and Reinsurance Premiums Included in Life Insurance Premiums (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>176</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R177.htm</HtmlFileName>
      <LongName>999169 - Disclosure - Income and Expenses Relating to Life Insurance Operations - Gains or Losses Relating to Variable Annuity and Variable Life Insurance Contracts (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/IncomeAndExpensesRelatingToLifeInsuranceOperationsGainsOrLossesRelatingToVariableAnnuityAndVariableLifeInsuranceContractsDetail</Role>
      <ShortName>Income and Expenses Relating to Life Insurance Operations - Gains or Losses Relating to Variable Annuity and Variable Life Insurance Contracts (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>177</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R178.htm</HtmlFileName>
      <LongName>999170 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Reconciliation of Liability For Future Policy Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfReconciliationOfLiabilityForFuturePolicyBenefitsDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Reconciliation of Liability For Future Policy Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>178</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R179.htm</HtmlFileName>
      <LongName>999171 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Policy Liabilities And Policy Account Balances In Statement of Financial Position (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfPolicyLiabilitiesAndPolicyAccountBalancesInStatementOfFinancialPositionDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Policy Liabilities And Policy Account Balances In Statement of Financial Position (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>179</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R180.htm</HtmlFileName>
      <LongName>999172 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit Expected Future Policy Benefit Undiscounted Before Reinsurance (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfLiabilityForFuturePolicyBenefitExpectedFuturePolicyBenefitUndiscountedBeforeReinsuranceDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit Expected Future Policy Benefit Undiscounted Before Reinsurance (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>180</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R181.htm</HtmlFileName>
      <LongName>999173 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit Gross Premiums And Interest Expense (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfLiabilityForFuturePolicyBenefitGrossPremiumsAndInterestExpenseDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit Gross Premiums And Interest Expense (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>181</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R182.htm</HtmlFileName>
      <LongName>999174 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit, Weighted Average Discount Rates (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfLiabilityForFuturePolicyBenefitWeightedAverageDiscountRatesDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit, Weighted Average Discount Rates (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>182</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R183.htm</HtmlFileName>
      <LongName>999175 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit, Weighted Average Duration (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfLiabilityForFuturePolicyBenefitWeightedAverageDurationDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Liability For Future Policy Benefit, Weighted Average Duration (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>183</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R184.htm</HtmlFileName>
      <LongName>999176 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Deferred Policy Acquisition Costs (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfDeferredPolicyAcquisitionCostsDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Deferred Policy Acquisition Costs (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>184</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R185.htm</HtmlFileName>
      <LongName>999177 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Minimum Guaranteed Interest Rates (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfMinimumGuaranteedInterestRatesDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Minimum Guaranteed Interest Rates (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>185</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R186.htm</HtmlFileName>
      <LongName>999178 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Minimum Guaranteed Interest Rates (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfMinimumGuaranteedInterestRatesParentheticalDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Minimum Guaranteed Interest Rates (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>186</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R187.htm</HtmlFileName>
      <LongName>999179 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Single-Payment Whole Life Insurance (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfSinglePaymentWholeLifeInsuranceDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Single-Payment Whole Life Insurance (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>187</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R188.htm</HtmlFileName>
      <LongName>999180 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Balances of Policy Account (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfBalancesOfPolicyAccountDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Balances of Policy Account (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>188</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R189.htm</HtmlFileName>
      <LongName>999181 - Disclosure - Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Policy Account Balance And Market Risk Benefits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/LongDurationInsuranceContractsRelatingToLifeInsuranceOperationsScheduleOfPolicyAccountBalanceAndMarketRiskBenefitsDetail</Role>
      <ShortName>Long-Duration Insurance Contracts Relating to Life Insurance Operations - Schedule of Policy Account Balance And Market Risk Benefits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>189</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R190.htm</HtmlFileName>
      <LongName>999182 - Disclosure - Write-Downs of Long-Lived Assets - Long-Lived Assets and Liabilities Associated With Those Assets Classified as Held for Sale (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/WriteDownsOfLongLivedAssetsLongLivedAssetsAndLiabilitiesAssociatedWithThoseAssetsClassifiedAsHeldForSaleDetail</Role>
      <ShortName>Write-Downs of Long-Lived Assets - Long-Lived Assets and Liabilities Associated With Those Assets Classified as Held for Sale (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>190</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R191.htm</HtmlFileName>
      <LongName>999183 - Disclosure - Write-Downs of Long-Lived Assets - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/WriteDownsOfLongLivedAssetsAdditionalInformationDetail</Role>
      <ShortName>Write-Downs of Long-Lived Assets - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>191</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R192.htm</HtmlFileName>
      <LongName>999184 - Disclosure - Write-Downs of Long-Lived Assets - Breakdowns of Recognized Impairment Losses for Difference between Carrying Amounts and Fair Values Reflected as Write-Downs of Long-Lived Assets (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/WriteDownsOfLongLivedAssetsBreakdownsOfRecognizedImpairmentLossesForDifferenceBetweenCarryingAmountsAndFairValuesReflectedAsWriteDownsOfLongLivedAssetsDetail</Role>
      <ShortName>Write-Downs of Long-Lived Assets - Breakdowns of Recognized Impairment Losses for Difference between Carrying Amounts and Fair Values Reflected as Write-Downs of Long-Lived Assets (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>192</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R193.htm</HtmlFileName>
      <LongName>999185 - Disclosure - Per Share Data - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PerShareDataAdditionalInformationDetail</Role>
      <ShortName>Per Share Data - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>193</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R194.htm</HtmlFileName>
      <LongName>999186 - Disclosure - Per Share Data (Reconciliation of Differences between Basic and Diluted Earnings Per Share) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/PerShareDataReconciliationOfDifferencesBetweenBasicAndDilutedEarningsPerShareDetail</Role>
      <ShortName>Per Share Data (Reconciliation of Differences between Basic and Diluted Earnings Per Share) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/PerShareDataTables</ParentRole>
      <Position>194</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R195.htm</HtmlFileName>
      <LongName>999187 - Disclosure - Derivative Financial Instruments and Hedging - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingAdditionalInformationDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>195</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R196.htm</HtmlFileName>
      <LongName>999188 - Disclosure - Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Cash flow hedges)  (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingEffectOfDerivativeInstrumentsOnConsolidatedStatementsOfIncomePreTaxCashFlowHedgesDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Cash flow hedges)  (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>196</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R197.htm</HtmlFileName>
      <LongName>999189 - Disclosure - Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Fair value hedges)  (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingEffectOfDerivativeInstrumentsOnConsolidatedStatementsOfIncomePreTaxFairValueHedgesDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Fair value hedges)  (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>197</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R198.htm</HtmlFileName>
      <LongName>999190 - Disclosure - Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Hedges of net investment in foreign operations)  (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingEffectOfDerivativeInstrumentsOnConsolidatedStatementsOfIncomePreTaxHedgesOfNetInvestmentInForeignOperationsDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Hedges of net investment in foreign operations)  (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>198</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R199.htm</HtmlFileName>
      <LongName>999191 - Disclosure - Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Derivatives not designated as hedging instruments)  (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingEffectOfDerivativeInstrumentsOnConsolidatedStatementsOfIncomePreTaxDerivativesNotDesignatedAsHedgingInstrumentsDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax, Derivatives not designated as hedging instruments)  (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>199</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R200.htm</HtmlFileName>
      <LongName>999192 - Disclosure - Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingEffectOfDerivativeInstrumentsOnConsolidatedStatementsOfIncomePreTaxDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Effect of Derivative Instruments on Consolidated Statements of Income, Pre-tax) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>200</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R201.htm</HtmlFileName>
      <LongName>999193 - Disclosure - Derivative Financial Instruments and Hedging (Derivative instruments fair value hedge assets and liabilities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingDerivativeInstrumentsFairValueHedgeAssetsAndLiabilitiesDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Derivative instruments fair value hedge assets and liabilities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>201</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R202.htm</HtmlFileName>
      <LongName>999194 - Disclosure - Derivative Financial Instruments and Hedging (Notional Amounts of Derivative Instruments and Other, Fair Values of Derivative Instruments and Other before Offsetting) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingNotionalAmountsOfDerivativeInstrumentsAndOtherFairValuesOfDerivativeInstrumentsAndOtherBeforeOffsettingDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Notional Amounts of Derivative Instruments and Other, Fair Values of Derivative Instruments and Other before Offsetting) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>202</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R203.htm</HtmlFileName>
      <LongName>999195 - Disclosure - Derivative Financial Instruments and Hedging (Notional Amounts of Derivative Instruments and Other, Fair Values of Derivative Instruments and Other before Offsetting) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingNotionalAmountsOfDerivativeInstrumentsAndOtherFairValuesOfDerivativeInstrumentsAndOtherBeforeOffsettingParentheticalDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Notional Amounts of Derivative Instruments and Other, Fair Values of Derivative Instruments and Other before Offsetting) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>203</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R204.htm</HtmlFileName>
      <LongName>999196 - Disclosure - Derivative Financial Instruments and Hedging (Credit Derivatives) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingCreditDerivativesDetail</Role>
      <ShortName>Derivative Financial Instruments and Hedging (Credit Derivatives) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/DerivativeFinancialInstrumentsAndHedgingTables</ParentRole>
      <Position>204</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R205.htm</HtmlFileName>
      <LongName>999197 - Disclosure - Offsetting Assets and Liabilities (Gross Amounts Recognized, Gross Amounts Offset, and Net Amounts Presented in Consolidated Balance Sheets Regarding to Derivative Assets and Liabilities and Other Assets and Liabilities) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/OffsettingAssetsAndLiabilitiesGrossAmountsRecognizedGrossAmountsOffsetAndNetAmountsPresentedInConsolidatedBalanceSheetsRegardingToDerivativeAssetsAndLiabilitiesAndOtherAssetsAndLiabilitiesDetail</Role>
      <ShortName>Offsetting Assets and Liabilities (Gross Amounts Recognized, Gross Amounts Offset, and Net Amounts Presented in Consolidated Balance Sheets Regarding to Derivative Assets and Liabilities and Other Assets and Liabilities) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/OffsettingAssetsAndLiabilitiesTables</ParentRole>
      <Position>205</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R206.htm</HtmlFileName>
      <LongName>999198 - Disclosure - Significant Concentrations of Credit Risk - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SignificantConcentrationsOfCreditRiskAdditionalInformationDetail</Role>
      <ShortName>Significant Concentrations of Credit Risk - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>206</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R207.htm</HtmlFileName>
      <LongName>999199 - Disclosure - Estimated Fair Value of Financial Instruments (Information about Carrying Amount of Financial Instruments Reported in Consolidated Balance Sheets and Related Market or Fair Value) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstrumentsInformationAboutCarryingAmountOfFinancialInstrumentsReportedInConsolidatedBalanceSheetsAndRelatedMarketOrFairValueDetail</Role>
      <ShortName>Estimated Fair Value of Financial Instruments (Information about Carrying Amount of Financial Instruments Reported in Consolidated Balance Sheets and Related Market or Fair Value) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstrumentsTables</ParentRole>
      <Position>207</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R208.htm</HtmlFileName>
      <LongName>999200 - Disclosure - Estimated Fair Value of Financial Instruments (Information about Carrying Amount of Financial Instruments Reported in Consolidated Balance Sheets and Related Market or Fair Value) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstrumentsInformationAboutCarryingAmountOfFinancialInstrumentsReportedInConsolidatedBalanceSheetsAndRelatedMarketOrFairValueParentheticalDetail</Role>
      <ShortName>Estimated Fair Value of Financial Instruments (Information about Carrying Amount of Financial Instruments Reported in Consolidated Balance Sheets and Related Market or Fair Value) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/EstimatedFairValueOfFinancialInstrumentsTables</ParentRole>
      <Position>208</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R209.htm</HtmlFileName>
      <LongName>999201 - Disclosure - Commitments, Guarantees, and Contingent Liabilities - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilitiesAdditionalInformationDetail</Role>
      <ShortName>Commitments, Guarantees, and Contingent Liabilities - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>209</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R210.htm</HtmlFileName>
      <LongName>999202 - Disclosure - Commitments, Guarantees and Contingent Liabilities (Amounts Due of Certain Computer Systems Operated and Maintained under Non-cancelable Contracts with Third-party Service Providers) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilitiesAmountsDueOfCertainComputerSystemsOperatedAndMaintainedUnderNonCancelableContractsWithThirdPartyServiceProvidersDetail</Role>
      <ShortName>Commitments, Guarantees and Contingent Liabilities (Amounts Due of Certain Computer Systems Operated and Maintained under Non-cancelable Contracts with Third-party Service Providers) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilitiesTables</ParentRole>
      <Position>210</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R211.htm</HtmlFileName>
      <LongName>999203 - Disclosure - Commitments, Guarantees, and Contingent Liabilities (Summary of Potential Future Payments, Book Value Recorded as Guarantee Liabilities of Guarantee Contracts Outstanding and Maturity of Longest Guarantee Contracts) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/CommitmentsGuaranteesAndContingentLiabilitiesSummaryOfPotentialFuturePaymentsBookValueRecordedAsGuaranteeLiabilitiesOfGuaranteeContractsOutstandingAndMaturityOfLongestGuaranteeContractsDetail</Role>
      <ShortName>Commitments, Guarantees, and Contingent Liabilities (Summary of Potential Future Payments, Book Value Recorded as Guarantee Liabilities of Guarantee Contracts Outstanding and Maturity of Longest Guarantee Contracts) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>211</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R212.htm</HtmlFileName>
      <LongName>999204 - Disclosure - Segment Information - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationAdditionalInformationDetail</Role>
      <ShortName>Segment Information - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>212</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R213.htm</HtmlFileName>
      <LongName>999205 - Disclosure - Segment Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationDetail</Role>
      <ShortName>Segment Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>213</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R214.htm</HtmlFileName>
      <LongName>999206 - Disclosure - Segment Information (Segment Assets) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationSegmentAssetsDetail</Role>
      <ShortName>Segment Information (Segment Assets) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>214</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R215.htm</HtmlFileName>
      <LongName>999207 - Disclosure - Segment Information (Segment Assets) (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationSegmentAssetsParentheticalDetail</Role>
      <ShortName>Segment Information (Segment Assets) (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>215</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R216.htm</HtmlFileName>
      <LongName>999208 - Disclosure - Segment Information (Reconciliation of Segment Totals to Consolidated Financial Statement Amounts) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationReconciliationOfSegmentTotalsToConsolidatedFinancialStatementAmountsDetail</Role>
      <ShortName>Segment Information (Reconciliation of Segment Totals to Consolidated Financial Statement Amounts) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>216</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R217.htm</HtmlFileName>
      <LongName>999209 - Disclosure - Segment Information (Geographical Revenues and Income before Income Taxes) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationGeographicalRevenuesAndIncomeBeforeIncomeTaxesDetail</Role>
      <ShortName>Segment Information (Geographical Revenues and Income before Income Taxes) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>217</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R218.htm</HtmlFileName>
      <LongName>999210 - Disclosure - Segment Information (Disaggregation of Revenues for Revenues From Contracts With Customers, by Goods and Services Category and Geographical Location) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SegmentInformationDisaggregationOfRevenuesForRevenuesFromContractsWithCustomersByGoodsAndServicesCategoryAndGeographicalLocationDetail</Role>
      <ShortName>Segment Information (Disaggregation of Revenues for Revenues From Contracts With Customers, by Goods and Services Category and Geographical Location) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://orixcorp.com/role/SegmentInformationTables</ParentRole>
      <Position>218</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R219.htm</HtmlFileName>
      <LongName>999211 - Disclosure - Subsequent Events - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/SubsequentEventsAdditionalInformationDetail</Role>
      <ShortName>Subsequent Events - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>219</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R220.htm</HtmlFileName>
      <LongName>999212 - Disclosure - Schedule II.-Valuation and Qualifying Accounts and Reserves (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ScheduleIiValuationAndQualifyingAccountsAndReservesDetail</Role>
      <ShortName>Schedule II.-Valuation and Qualifying Accounts and Reserves (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>220</Position>
    </Report>
    <Report instance="d29000d20f.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R221.htm</HtmlFileName>
      <LongName>999213 - Disclosure - Schedule II.-Valuation and Qualifying Accounts and Reserves (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://orixcorp.com/role/ScheduleIiValuationAndQualifyingAccountsAndReservesParentheticalDetail</Role>
      <ShortName>Schedule II.-Valuation and Qualifying Accounts and Reserves (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>221</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="20-F" isDefinitelyFs="true" isUsgaap="true" original="d29000d20f.htm">d29000d20f.htm</File>
    <File>ix-20260331.xsd</File>
  </InputFiles>
  <SupplementalFiles>
    <File>g29000g00k01.jpg</File>
    <File>g29000g00k02.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="1">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="7205">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="15">http://xbrl.sec.gov/cyd/2025</BaseTaxonomy>
    <BaseTaxonomy items="49">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="1">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>false</HasPresentationLinkbase>
  <HasCalculationLinkbase>false</HasCalculationLinkbase>
</FilingSummary>
