<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.10.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>172</ContextCount>
  <ElementCount>306</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>73</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>8</UnitCount>
  <MyReports>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>00090 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>00100 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/StatementCondensedConsolidatedBalanceSheetsUnaudited</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>00105 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical</Role>
      <ShortName>CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>00200 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfOperationsUnaudited</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>00300 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfComprehensiveIncomeUnaudited</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>00400 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited</Role>
      <ShortName>CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>10101 - Disclosure - Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentation</Role>
      <ShortName>Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>10201 - Disclosure - Business Combinations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinations</Role>
      <ShortName>Business Combinations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>10301 - Disclosure - Balance Sheet Details</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBalanceSheetDetails</Role>
      <ShortName>Balance Sheet Details</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>10401 - Disclosure - Goodwill and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssets</Role>
      <ShortName>Goodwill and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>10501 - Disclosure - Restructuring and Other Charges</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRestructuringAndOtherCharges</Role>
      <ShortName>Restructuring and Other Charges</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>10601 - Disclosure - Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBorrowings</Role>
      <ShortName>Borrowings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>10701 - Disclosure - Stockholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureStockholdersEquity</Role>
      <ShortName>Stockholders' Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>10801 - Disclosure - Retirement Benefit Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRetirementBenefitPlans</Role>
      <ShortName>Retirement Benefit Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>10901 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>11001 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureIncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>11101 - Disclosure - Segment Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureSegmentInformation</Role>
      <ShortName>Segment Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>20102 - Disclosure - Basis of Presentation (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationPolicies</Role>
      <ShortName>Basis of Presentation (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>30103 - Disclosure - Basis of Presentation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationTables</Role>
      <ShortName>Basis of Presentation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBasisOfPresentation</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>30203 - Disclosure - Business Combinations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinationsTables</Role>
      <ShortName>Business Combinations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBusinessCombinations</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>30303 - Disclosure - Balance Sheet Details (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBalanceSheetDetailsTables</Role>
      <ShortName>Balance Sheet Details (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBalanceSheetDetails</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>30403 - Disclosure - Goodwill and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsTables</Role>
      <ShortName>Goodwill and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssets</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>30503 - Disclosure - Restructuring and Other Charges (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesTables</Role>
      <ShortName>Restructuring and Other Charges (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureRestructuringAndOtherCharges</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>30603 - Disclosure - Borrowings (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBorrowingsTables</Role>
      <ShortName>Borrowings (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBorrowings</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>30703 - Disclosure - Stockholders' Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureStockholdersEquityTables</Role>
      <ShortName>Stockholders' Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureStockholdersEquity</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>30803 - Disclosure - Retirement Benefit Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRetirementBenefitPlansTables</Role>
      <ShortName>Retirement Benefit Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureRetirementBenefitPlans</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>30903 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureCommitmentsAndContingencies</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>31103 - Disclosure - Segment Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureSegmentInformationTables</Role>
      <ShortName>Segment Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureSegmentInformation</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>40101 - Disclosure - Basis of Presentation - Description of Business (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationDescriptionOfBusinessDetails</Role>
      <ShortName>Basis of Presentation - Description of Business (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>40102 - Disclosure - Basis of Presentation - Per Share Computations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationPerShareComputationsDetails</Role>
      <ShortName>Basis of Presentation - Per Share Computations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>40103 - Disclosure - Basis of Presentation - Cash Equivalents (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationCashEquivalentsDetails</Role>
      <ShortName>Basis of Presentation - Cash Equivalents (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>40104 - Disclosure - Basis of Presentation - Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationFairValueDetails</Role>
      <ShortName>Basis of Presentation - Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>40105 - Disclosure - Basis of Presentation - Revenue Recognition (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBasisOfPresentationRevenueRecognitionDetails</Role>
      <ShortName>Basis of Presentation - Revenue Recognition (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>40201 - Disclosure - Business Combinations - Fiscal Year 2019 Business Acquisitions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinationsFiscalYear2019BusinessAcquisitionsDetails</Role>
      <ShortName>Business Combinations - Fiscal Year 2019 Business Acquisitions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>40202 - Disclosure - Business Combinations - Explosive Trace Detection (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinationsExplosiveTraceDetectionDetails</Role>
      <ShortName>Business Combinations - Explosive Trace Detection (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>40203 - Disclosure - Business Combinations - Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinationsIntangibleAssetsDetails</Role>
      <ShortName>Business Combinations - Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>40204 - Disclosure - Business Combinations - Other Business Acquisition (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBusinessCombinationsOtherBusinessAcquisitionDetails</Role>
      <ShortName>Business Combinations - Other Business Acquisition (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>40301 - Disclosure - Balance Sheet Details (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBalanceSheetDetailsDetails</Role>
      <ShortName>Balance Sheet Details (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBalanceSheetDetailsTables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>40401 - Disclosure - Goodwill and Intangible Assets - Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsGoodwillDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>40402 - Disclosure - Goodwill and Intangible Assets - Intangible Assets Subject to Amortization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsIntangibleAssetsSubjectToAmortizationDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Intangible Assets Subject to Amortization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>40403 - Disclosure - Goodwill and Intangible Assets - Intangible Amortization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureGoodwillAndIntangibleAssetsIntangibleAmortizationDetails</Role>
      <ShortName>Goodwill and Intangible Assets - Intangible Amortization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>40501 - Disclosure - Restructuring and Other Charges - Restructuring and other charges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesRestructuringAndOtherChargesDetails</Role>
      <ShortName>Restructuring and Other Charges - Restructuring and other charges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>40502 - Disclosure - Restructuring and Other Charges - Changes in the accrual for restructuring and other charges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRestructuringAndOtherChargesChangesInAccrualForRestructuringAndOtherChargesDetails</Role>
      <ShortName>Restructuring and Other Charges - Changes in the accrual for restructuring and other charges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>40601 - Disclosure - Borrowings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureBorrowingsDetails</Role>
      <ShortName>Borrowings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureBorrowingsTables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>40701 - Disclosure - Stockholders' Equity - Stock-based Compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureStockholdersEquityStockBasedCompensationDetails</Role>
      <ShortName>Stockholders' Equity - Stock-based Compensation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>40702 - Disclosure - Stockholders' Equity - Share Repurchase Program (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureStockholdersEquityShareRepurchaseProgramDetails</Role>
      <ShortName>Stockholders' Equity - Share Repurchase Program (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>40801 - Disclosure - Retirement Benefit Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureRetirementBenefitPlansDetails</Role>
      <ShortName>Retirement Benefit Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureRetirementBenefitPlansTables</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>40901 - Disclosure - Commitments and Contingencies - Contingent Acquisition Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesContingentAcquisitionObligationsDetails</Role>
      <ShortName>Commitments and Contingencies - Contingent Acquisition Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>40902 - Disclosure - Commitments and Contingencies - Product Warranties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureCommitmentsAndContingenciesProductWarrantiesDetails</Role>
      <ShortName>Commitments and Contingencies - Product Warranties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>41001 - Disclosure - Income Taxes - (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureIncomeTaxesDetails</Role>
      <ShortName>Income Taxes - (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.osi-systems.com/role/DisclosureIncomeTaxes</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="osis-20180930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>41101 - Disclosure - Segment Information - Operations and Identifiable Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.osi-systems.com/role/DisclosureSegmentInformationOperationsAndIdentifiableAssetsDetails</Role>
      <ShortName>Segment Information - Operations and Identifiable Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>osis-20180930.xml</File>
    <File>osis-20180930.xsd</File>
    <File>osis-20180930_cal.xml</File>
    <File>osis-20180930_def.xml</File>
    <File>osis-20180930_lab.xml</File>
    <File>osis-20180930_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/us-gaap/2018-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://fasb.org/srt/2018-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2018-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
