<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.25.4</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>1816</ContextCount>
  <ElementCount>322</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>178</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>16</UnitCount>
  <MyReports>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>0000002 - Statement - Consolidated Statements of Assets and Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofAssetsandLiabilities</Role>
      <ShortName>Consolidated Statements of Assets and Liabilities</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>0000003 - Statement - Consolidated Statements of Assets and Liabilities - Parenthetical 1</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofAssetsandLiabilitiesParenthetical1</Role>
      <ShortName>Consolidated Statements of Assets and Liabilities - Parenthetical 1</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>0000004 - Statement - Consolidated Statements of Assets and Liabilities - Parenthetical 2</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofAssetsandLiabilitiesParenthetical2</Role>
      <ShortName>Consolidated Statements of Assets and Liabilities - Parenthetical 2</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>0000005 - Statement - Consolidated Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofOperations</Role>
      <ShortName>Consolidated Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>0000006 - Statement - Consolidated Statements of Changes in Net Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofChangesinNetAssets</Role>
      <ShortName>Consolidated Statements of Changes in Net Assets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>0000007 - Statement - Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofCashFlows</Role>
      <ShortName>Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>0000008 - Statement - Consolidated Statements of Cash Flows - Parenthetical</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedStatementsofCashFlowsParenthetical</Role>
      <ShortName>Consolidated Statements of Cash Flows - Parenthetical</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>0000009 - Statement - Consolidated Schedule of Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedScheduleofInvestments</Role>
      <ShortName>Consolidated Schedule of Investments</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>0000010 - Statement - Consolidated Schedule of Investments - Derivatives, Foreign Currency Forward Contracts</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedScheduleofInvestmentsDerivativesForeignCurrencyForwardContracts</Role>
      <ShortName>Consolidated Schedule of Investments - Derivatives, Foreign Currency Forward Contracts</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>0000011 - Statement - Consolidated Schedule of Investments - Derivatives, Interest Rate Swap</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedScheduleofInvestmentsDerivativesInterestRateSwap</Role>
      <ShortName>Consolidated Schedule of Investments - Derivatives, Interest Rate Swap</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>0000012 - Statement - Consolidated Schedule of Investments - Parenthetical</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConsolidatedScheduleofInvestmentsParenthetical</Role>
      <ShortName>Consolidated Schedule of Investments - Parenthetical</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>0000013 - Disclosure - Organization</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/Organization</Role>
      <ShortName>Organization</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>0000014 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SignificantAccountingPolicies</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>0000015 - Disclosure - Portfolio Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestments</Role>
      <ShortName>Portfolio Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>0000016 - Disclosure - Fee Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/FeeIncome</Role>
      <ShortName>Fee Income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>0000017 - Disclosure - Share Data and Distributions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributions</Role>
      <ShortName>Share Data and Distributions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>0000018 - Disclosure - Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/Borrowings</Role>
      <ShortName>Borrowings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>0000019 - Disclosure - Taxable/Distributable Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/TaxableDistributableIncome</Role>
      <ShortName>Taxable/Distributable Income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>0000020 - Disclosure - Concentration of Credit Risks</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ConcentrationofCreditRisks</Role>
      <ShortName>Concentration of Credit Risks</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>0000021 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>0000022 - Disclosure - Financial Highlights</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/FinancialHighlights</Role>
      <ShortName>Financial Highlights</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>0000023 - Disclosure - Derivative Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/DerivativeInstruments</Role>
      <ShortName>Derivative Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>0000024 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>0000025 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>995445 - Disclosure - Insider Trading Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements</Role>
      <ShortName>Insider Trading Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SignificantAccountingPoliciesPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://oscf.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Portfolio Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsTables</Role>
      <ShortName>Portfolio Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/PortfolioInvestments</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Share Data and Distributions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsTables</Role>
      <ShortName>Share Data and Distributions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/ShareDataandDistributions</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Borrowings (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/BorrowingsTables</Role>
      <ShortName>Borrowings (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/Borrowings</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Taxable/Distributable Income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/TaxableDistributableIncomeTables</Role>
      <ShortName>Taxable/Distributable Income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/TaxableDistributableIncome</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Related Party Transactions (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/RelatedPartyTransactionsTables</Role>
      <ShortName>Related Party Transactions (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/RelatedPartyTransactions</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Financial Highlights (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/FinancialHighlightsTables</Role>
      <ShortName>Financial Highlights (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/FinancialHighlights</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Derivative Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/DerivativeInstrumentsTables</Role>
      <ShortName>Derivative Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/DerivativeInstruments</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/CommitmentsandContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/CommitmentsandContingencies</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Subsequent Events (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SubsequentEventsTables</Role>
      <ShortName>Subsequent Events (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://oscf.com/role/SubsequentEvents</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Organization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/OrganizationDetails</Role>
      <ShortName>Organization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://oscf.com/role/Organization</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SignificantAccountingPoliciesDetails</Role>
      <ShortName>Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://oscf.com/role/SignificantAccountingPoliciesPolicies</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Portfolio Investments - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsNarrativeDetails</Role>
      <ShortName>Portfolio Investments - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Portfolio Investments - Schedule of Portfolio Composition (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofPortfolioCompositionDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Portfolio Composition (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Portfolio Investments - Schedule of Composition of Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofCompositionofInvestmentsDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Composition of Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Portfolio Investments - Schedule of Portfolio of Investments by Industry (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofPortfolioofInvestmentsbyIndustryDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Portfolio of Investments by Industry (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Portfolio Investments - Schedule of Financial Instruments Carried at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofFinancialInstrumentsCarriedatFairValueDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Financial Instruments Carried at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Portfolio Investments - Schedule of Roll-forward of the Changes in Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofRollforwardoftheChangesinFairValueDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Roll-forward of the Changes in Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Portfolio Investments - Schedule of Significant Unobservable Inputs for Level 3 Investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/PortfolioInvestmentsScheduleofSignificantUnobservableInputsforLevel3InvestmentsDetails</Role>
      <ShortName>Portfolio Investments - Schedule of Significant Unobservable Inputs for Level 3 Investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Fee Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/FeeIncomeDetails</Role>
      <ShortName>Fee Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://oscf.com/role/FeeIncome</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Share Data and Distributions - Schedule of Changes in Net Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsScheduleofChangesinNetAssetsDetails</Role>
      <ShortName>Share Data and Distributions - Schedule of Changes in Net Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Share Data and Distributions - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsNarrativeDetails</Role>
      <ShortName>Share Data and Distributions - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Share Data and Distributions - Schedule of Transactions in Common Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsScheduleofTransactionsinCommonSharesDetails</Role>
      <ShortName>Share Data and Distributions - Schedule of Transactions in Common Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Share Data and Distributions - Schedule of Distributions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsScheduleofDistributionsDetails</Role>
      <ShortName>Share Data and Distributions - Schedule of Distributions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>50</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Share Data and Distributions - Schedule of Share Repurchases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/ShareDataandDistributionsScheduleofShareRepurchasesDetails</Role>
      <ShortName>Share Data and Distributions - Schedule of Share Repurchases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Borrowings - Schedule of Credit Facilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/BorrowingsScheduleofCreditFacilitiesDetails</Role>
      <ShortName>Borrowings - Schedule of Credit Facilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Borrowings - Schedule of Unsecured Notes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://oscf.com/role/BorrowingsScheduleofUnsecuredNotesDetails</Role>
      <ShortName>Borrowings - Schedule of Unsecured Notes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Borrowings - Schedule of Components of Interest Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/BorrowingsScheduleofComponentsofInterestExpensesDetails</Role>
      <ShortName>Borrowings - Schedule of Components of Interest Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Borrowings - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/BorrowingsNarrativeDetails</Role>
      <ShortName>Borrowings - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Taxable/Distributable Income - Schedule of Reconciliation of Net Increase (Decrease) in Net Assets Resulting from Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/TaxableDistributableIncomeScheduleofReconciliationofNetIncreaseDecreaseinNetAssetsResultingfromOperationsDetails</Role>
      <ShortName>Taxable/Distributable Income - Schedule of Reconciliation of Net Increase (Decrease) in Net Assets Resulting from Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Taxable/Distributable Income - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/TaxableDistributableIncomeNarrativeDetails</Role>
      <ShortName>Taxable/Distributable Income - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Taxable/Distributable Income - Schedule of Components of Accumulated Overdistributed Earnings (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/TaxableDistributableIncomeScheduleofComponentsofAccumulatedOverdistributedEarningsDetails</Role>
      <ShortName>Taxable/Distributable Income - Schedule of Components of Accumulated Overdistributed Earnings (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Related Party Transactions - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/RelatedPartyTransactionsNarrativeDetails</Role>
      <ShortName>Related Party Transactions - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Related Party Transactions - Schedule of Shareholder Servicing and/or Distribution Fees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/RelatedPartyTransactionsScheduleofShareholderServicingandorDistributionFeesDetails</Role>
      <ShortName>Related Party Transactions - Schedule of Shareholder Servicing and/or Distribution Fees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Financial Highlights (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/FinancialHighlightsDetails</Role>
      <ShortName>Financial Highlights (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://oscf.com/role/FinancialHighlightsTables</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Derivative Instruments - Schedule of Foreign Currency Forward Contracts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/DerivativeInstrumentsScheduleofForeignCurrencyForwardContractsDetails</Role>
      <ShortName>Derivative Instruments - Schedule of Foreign Currency Forward Contracts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - Derivative Instruments - Schedule of Interest Rate Swaps (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/DerivativeInstrumentsScheduleofInterestRateSwapsDetails</Role>
      <ShortName>Derivative Instruments - Schedule of Interest Rate Swaps (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - Commitments and Contingencies - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/CommitmentsandContingenciesNarrativeDetails</Role>
      <ShortName>Commitments and Contingencies - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - Commitments and Contingencies - Schedule of Unfunded Commitments by Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/CommitmentsandContingenciesScheduleofUnfundedCommitmentsbyInvestmentDetails</Role>
      <ShortName>Commitments and Contingencies - Schedule of Unfunded Commitments by Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - Subsequent Events - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SubsequentEventsNarrativeDetails</Role>
      <ShortName>Subsequent Events - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="oscf-20251231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - Subsequent Events - Schedule of Distributions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://oscf.com/role/SubsequentEventsScheduleofDistributionsDetails</Role>
      <ShortName>Subsequent Events - Schedule of Distributions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-Q" isDefinitelyFs="true" isUsgaap="true" original="oscf-20251231.htm">oscf-20251231.htm</File>
    <File>oscf-20251231.xsd</File>
    <File>oscf-20251231_cal.xml</File>
    <File>oscf-20251231_def.xml</File>
    <File>oscf-20251231_lab.xml</File>
    <File>oscf-20251231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="2">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="5798">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="30">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="4">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
