<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>949</ContextCount>
  <ElementCount>655</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>267</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>37</UnitCount>
  <MyReports>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover Page</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CoverPage</Role>
      <ShortName>Cover Page</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - Condensed Consolidated Balance Sheets (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedBalanceSheetsUnaudited</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedBalanceSheetsUnauditedParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - Condensed Consolidated Statements of Operations (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedStatementsofOperationsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Operations (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - Condensed Consolidated Statements of Comprehensive Income (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedStatementsofComprehensiveIncomeUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Comprehensive Income (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Statement - Condensed Consolidated Statements of Equity (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedStatementsofEquityUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Equity (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Statement - Condensed Consolidated Statements of Equity (Unaudited) (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedStatementsofEquityUnauditedParenthetical</Role>
      <ShortName>Condensed Consolidated Statements of Equity (Unaudited) (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CondensedConsolidatedStatementsofCashFlowsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - Business and Organization</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/BusinessandOrganization</Role>
      <ShortName>Business and Organization</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SummaryofSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Acquisitions and Divestitures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/AcquisitionsandDivestitures</Role>
      <ShortName>Acquisitions and Divestitures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Loans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/Loans</Role>
      <ShortName>Loans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Investment Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecurities</Role>
      <ShortName>Investment Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Properties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/Properties</Role>
      <ShortName>Properties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>9952164 - Disclosure - Investments of Consolidated Affordable Housing Fund</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFund</Role>
      <ShortName>Investments of Consolidated Affordable Housing Fund</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9952165 - Disclosure - Investments in Unconsolidated Entities???</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsinUnconsolidatedEntities</Role>
      <ShortName>Investments in Unconsolidated Entities???</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9952166 - Disclosure - Goodwill and Intangibles</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangibles</Role>
      <ShortName>Goodwill and Intangibles</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9952167 - Disclosure - Secured Borrowings</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowings</Role>
      <ShortName>Secured Borrowings</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9952168 - Disclosure - Unsecured Senior Notes</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotes</Role>
      <ShortName>Unsecured Senior Notes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9952169 - Disclosure - Loan Securitization/Sale Activities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivities</Role>
      <ShortName>Loan Securitization/Sale Activities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9952170 - Disclosure - Derivatives and Hedging Activity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivity</Role>
      <ShortName>Derivatives and Hedging Activity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9952171 - Disclosure - Offsetting Assets and Liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/OffsettingAssetsandLiabilities</Role>
      <ShortName>Offsetting Assets and Liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9952172 - Disclosure - Variable Interest Entities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/VariableInterestEntities</Role>
      <ShortName>Variable Interest Entities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9952173 - Disclosure - Related-Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related-Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9952174 - Disclosure - Stockholders' Equity and Non-Controlling Interests</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterests</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9952175 - Disclosure - Earnings per Share</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/EarningsperShare</Role>
      <ShortName>Earnings per Share</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9952176 - Disclosure - Accumulated Other Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/AccumulatedOtherComprehensiveIncome</Role>
      <ShortName>Accumulated Other Comprehensive Income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9952177 - Disclosure - Fair Value</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValue</Role>
      <ShortName>Fair Value</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9952178 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9952179 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9952180 - Disclosure - Segment Data</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SegmentData</Role>
      <ShortName>Segment Data</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9952181 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.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>33</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SummaryofSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/SummaryofSignificantAccountingPolicies</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Loans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansTables</Role>
      <ShortName>Loans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/Loans</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Investment Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesTables</Role>
      <ShortName>Investment Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/InvestmentSecurities</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Properties (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/PropertiesTables</Role>
      <ShortName>Properties (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/Properties</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Investments of Consolidated Affordable Housing Fund (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFundTables</Role>
      <ShortName>Investments of Consolidated Affordable Housing Fund (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFund</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Investments in Unconsolidated Entities??? (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsinUnconsolidatedEntitiesTables</Role>
      <ShortName>Investments in Unconsolidated Entities??? (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/InvestmentsinUnconsolidatedEntities</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Goodwill and Intangibles (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangiblesTables</Role>
      <ShortName>Goodwill and Intangibles (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/GoodwillandIntangibles</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Secured Borrowings (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowingsTables</Role>
      <ShortName>Secured Borrowings (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/SecuredBorrowings</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Unsecured Senior Notes (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotesTables</Role>
      <ShortName>Unsecured Senior Notes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotes</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Loan Securitization/Sale Activities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivitiesTables</Role>
      <ShortName>Loan Securitization/Sale Activities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivities</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Derivatives and Hedging Activity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivityTables</Role>
      <ShortName>Derivatives and Hedging Activity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivity</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Offsetting Assets and Liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/OffsettingAssetsandLiabilitiesTables</Role>
      <ShortName>Offsetting Assets and Liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/OffsettingAssetsandLiabilities</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Variable Interest Entities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/VariableInterestEntitiesTables</Role>
      <ShortName>Variable Interest Entities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/VariableInterestEntities</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Stockholders' Equity and Non-Controlling Interests (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsTables</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterests</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Earnings per Share (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/EarningsperShareTables</Role>
      <ShortName>Earnings per Share (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/EarningsperShare</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Accumulated Other Comprehensive Income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/AccumulatedOtherComprehensiveIncomeTables</Role>
      <ShortName>Accumulated Other Comprehensive Income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/AccumulatedOtherComprehensiveIncome</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Fair Value (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueTables</Role>
      <ShortName>Fair Value (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/FairValue</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/IncomeTaxes</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Segment Data (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SegmentDataTables</Role>
      <ShortName>Segment Data (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/SegmentData</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Business and Organization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/BusinessandOrganizationDetails</Role>
      <ShortName>Business and Organization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/BusinessandOrganization</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SummaryofSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/SummaryofSignificantAccountingPoliciesPolicies</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Acquisitions and Divestitures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/AcquisitionsandDivestituresDetails</Role>
      <ShortName>Acquisitions and Divestitures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/AcquisitionsandDivestitures</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Loans - Investments in Mortgages and Loans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansInvestmentsinMortgagesandLoansDetails</Role>
      <ShortName>Loans - Investments in Mortgages and Loans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>56</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Loans - Variable Rate Loans Held for Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansVariableRateLoansHeldforInvestmentDetails</Role>
      <ShortName>Loans - Variable Rate Loans Held for Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Loans - Risk Ratings by Class of Loan (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansRiskRatingsbyClassofLoanDetails</Role>
      <ShortName>Loans - Risk Ratings by Class of Loan (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Loans - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansNarrativeDetails</Role>
      <ShortName>Loans - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Loans - Activity in Portfolio (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoansActivityinPortfolioDetails</Role>
      <ShortName>Loans - Activity in Portfolio (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Investment Securities - Investment Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesInvestmentSecuritiesDetails</Role>
      <ShortName>Investment Securities - Investment Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Investment Securities - Purchases, Sales and Redemptions, and Principal Collections for All Investment Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesPurchasesSalesandRedemptionsandPrincipalCollectionsforAllInvestmentSecuritiesDetails</Role>
      <ShortName>Investment Securities - Purchases, Sales and Redemptions, and Principal Collections for All Investment Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Investment Securities - Available-for-Sale RMBS (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesAvailableforSaleRMBSDetails</Role>
      <ShortName>Investment Securities - Available-for-Sale RMBS (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Investment Securities - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesNarrativeDetails</Role>
      <ShortName>Investment Securities - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Investment Securities - AFS and Fair Value Option (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesAFSandFairValueOptionDetails</Role>
      <ShortName>Investment Securities - AFS and Fair Value Option (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Investment Securities - HTM Debt Securities, Amortized Cost??? (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentSecuritiesHTMDebtSecuritiesAmortizedCostDetails</Role>
      <ShortName>Investment Securities - HTM Debt Securities, Amortized Cost??? (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Properties - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/PropertiesNarrativeDetails</Role>
      <ShortName>Properties - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Properties - Properties Held (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/PropertiesPropertiesHeldDetails</Role>
      <ShortName>Properties - Properties Held (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Investments of Consolidated Affordable Housing Fund - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFundNarrativeDetails</Role>
      <ShortName>Investments of Consolidated Affordable Housing Fund - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFundTables</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>9955547 - Disclosure - Investments of Consolidated Affordable Housing Fund - Investment Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsofConsolidatedAffordableHousingFundInvestmentIncomeDetails</Role>
      <ShortName>Investments of Consolidated Affordable Housing Fund - Investment Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>9955548 - Disclosure - Investments in Unconsolidated Entities??? - Investments in Unconsolidated Entities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsinUnconsolidatedEntitiesInvestmentsinUnconsolidatedEntitiesDetails</Role>
      <ShortName>Investments in Unconsolidated Entities??? - Investments in Unconsolidated Entities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>9955549 - Disclosure - Investments in Unconsolidated Entities??? - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/InvestmentsinUnconsolidatedEntitiesNarrativeDetails</Role>
      <ShortName>Investments in Unconsolidated Entities??? - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>9955550 - Disclosure - Goodwill and Intangibles - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangiblesNarrativeDetails</Role>
      <ShortName>Goodwill and Intangibles - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>9955551 - Disclosure - Goodwill and Intangibles - Intangibles Assets And Intangible Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangiblesIntangiblesAssetsAndIntangibleLiabilitiesDetails</Role>
      <ShortName>Goodwill and Intangibles - Intangibles Assets And Intangible Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>9955552 - Disclosure - Goodwill and Intangibles - Activity Within Intangible Assets and Intangible Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangiblesActivityWithinIntangibleAssetsandIntangibleLiabilitiesDetails</Role>
      <ShortName>Goodwill and Intangibles - Activity Within Intangible Assets and Intangible Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>75</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>9955553 - Disclosure - Goodwill and Intangibles - Future Expected Amortization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/GoodwillandIntangiblesFutureExpectedAmortizationDetails</Role>
      <ShortName>Goodwill and Intangibles - Future Expected Amortization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>9955554 - Disclosure - Secured Borrowings - Secured Financing Agreements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowingsSecuredFinancingAgreementsDetails</Role>
      <ShortName>Secured Borrowings - Secured Financing Agreements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>9955555 - Disclosure - Secured Borrowings - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowingsNarrativeDetails</Role>
      <ShortName>Secured Borrowings - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>9955556 - Disclosure - Secured Borrowings - Collateralized Loan Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowingsCollateralizedLoanObligationsDetails</Role>
      <ShortName>Secured Borrowings - Collateralized Loan Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>9955557 - Disclosure - Secured Borrowings - Principal Repayments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SecuredBorrowingsPrincipalRepaymentsDetails</Role>
      <ShortName>Secured Borrowings - Principal Repayments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>9955558 - Disclosure - Unsecured Senior Notes - Unsecured Convertible Senior Notes Outstanding (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotesUnsecuredConvertibleSeniorNotesOutstandingDetails</Role>
      <ShortName>Unsecured Senior Notes - Unsecured Convertible Senior Notes Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>9955559 - Disclosure - Unsecured Senior Notes - Narrative (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotesNarrativeDetails</Role>
      <ShortName>Unsecured Senior Notes - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>9955560 - Disclosure - Unsecured Senior Notes - Convertible Notes (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/UnsecuredSeniorNotesConvertibleNotesDetails</Role>
      <ShortName>Unsecured Senior Notes - Convertible Notes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>9955561 - Disclosure - Loan Securitization/Sale Activities - Loans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivitiesLoansDetails</Role>
      <ShortName>Loan Securitization/Sale Activities - Loans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivitiesTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>9955562 - Disclosure - Loan Securitization/Sale Activities - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/LoanSecuritizationSaleActivitiesNarrativeDetails</Role>
      <ShortName>Loan Securitization/Sale Activities - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>9955563 - Disclosure - Derivatives and Hedging Activity - Designated and Non-Designated Hedges (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivityDesignatedandNonDesignatedHedgesDetails</Role>
      <ShortName>Derivatives and Hedging Activity - Designated and Non-Designated Hedges (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>9955564 - Disclosure - Derivatives and Hedging Activity - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivityNarrativeDetails</Role>
      <ShortName>Derivatives and Hedging Activity - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>9955565 - Disclosure - Derivatives and Hedging Activity - Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivityFairValueDetails</Role>
      <ShortName>Derivatives and Hedging Activity - Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>9955566 - Disclosure - Derivatives and Hedging Activity - Effect of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/DerivativesandHedgingActivityEffectofFinancialInstrumentsDetails</Role>
      <ShortName>Derivatives and Hedging Activity - Effect of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>9955567 - Disclosure - Offsetting Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/OffsettingAssetsandLiabilitiesDetails</Role>
      <ShortName>Offsetting Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/OffsettingAssetsandLiabilitiesTables</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>9955568 - Disclosure - Variable Interest Entities - Assets and Liabilities of Consolidated CLO (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/VariableInterestEntitiesAssetsandLiabilitiesofConsolidatedCLODetails</Role>
      <ShortName>Variable Interest Entities - Assets and Liabilities of Consolidated CLO (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>9955569 - Disclosure - Variable Interest Entities - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/VariableInterestEntitiesNarrativeDetails</Role>
      <ShortName>Variable Interest Entities - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>9955570 - Disclosure - Related-Party Transactions - Management Agreement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactionsManagementAgreementDetails</Role>
      <ShortName>Related-Party Transactions - Management Agreement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>9955571 - Disclosure - Related-Party Transactions - Manager Equity Plan (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactionsManagerEquityPlanDetails</Role>
      <ShortName>Related-Party Transactions - Manager Equity Plan (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>94</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>9955572 - Disclosure - Related-Party Transactions - Investments in Loans and Securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactionsInvestmentsinLoansandSecuritiesDetails</Role>
      <ShortName>Related-Party Transactions - Investments in Loans and Securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>95</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>9955573 - Disclosure - Related-Party Transactions - Lease Arrangements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactionsLeaseArrangementsDetails</Role>
      <ShortName>Related-Party Transactions - Lease Arrangements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>96</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>9955574 - Disclosure - Related-Party Transactions - Other Related-Party Arrangements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/RelatedPartyTransactionsOtherRelatedPartyArrangementsDetails</Role>
      <ShortName>Related-Party Transactions - Other Related-Party Arrangements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>97</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>9955575 - Disclosure - Stockholders' Equity and Non-Controlling Interests - Declared Dividends (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsDeclaredDividendsDetails</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests - Declared Dividends (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>98</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>9955576 - Disclosure - Stockholders' Equity and Non-Controlling Interests - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsNarrativeDetails</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsTables</ParentRole>
      <Position>99</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>9955577 - Disclosure - Stockholders' Equity and Non-Controlling Interests - Equity Incentive Plans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsEquityIncentivePlansDetails</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests - Equity Incentive Plans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>9955578 - Disclosure - Stockholders' Equity and Non-Controlling Interests - Non-Vested Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/StockholdersEquityandNonControllingInterestsNonVestedSharesDetails</Role>
      <ShortName>Stockholders' Equity and Non-Controlling Interests - Non-Vested Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>101</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>9955579 - Disclosure - Earnings per Share - Reconciliation of Net Income and Number of Shares used in Computation of Earnings Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/EarningsperShareReconciliationofNetIncomeandNumberofSharesusedinComputationofEarningsPerShareDetails</Role>
      <ShortName>Earnings per Share - Reconciliation of Net Income and Number of Shares used in Computation of Earnings Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>102</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>9955580 - Disclosure - Earnings per Share - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/EarningsperShareNarrativeDetails</Role>
      <ShortName>Earnings per Share - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>103</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>9955581 - Disclosure - Accumulated Other Comprehensive Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/AccumulatedOtherComprehensiveIncomeDetails</Role>
      <ShortName>Accumulated Other Comprehensive Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/AccumulatedOtherComprehensiveIncomeTables</ParentRole>
      <Position>104</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>9955582 - Disclosure - Fair Value - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueNarrativeDetails</Role>
      <ShortName>Fair Value - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>9955583 - Disclosure - Fair Value - Financial Assets and Liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueFinancialAssetsandLiabilitiesDetails</Role>
      <ShortName>Fair Value - Financial Assets and Liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>106</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>9955584 - Disclosure - Fair Value - Level III (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueLevelIIIDetails</Role>
      <ShortName>Fair Value - Level III (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>9955585 - Disclosure - Fair Value - Financial Instruments not Carried at Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueFinancialInstrumentsnotCarriedatFairValueDetails</Role>
      <ShortName>Fair Value - Financial Instruments not Carried at Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>9955586 - Disclosure - Fair Value - Significant Unobservable Inputs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/FairValueSignificantUnobservableInputsDetails</Role>
      <ShortName>Fair Value - Significant Unobservable Inputs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>9955587 - Disclosure - Income Taxes - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/IncomeTaxesNarrativeDetails</Role>
      <ShortName>Income Taxes - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>9955588 - Disclosure - Income Taxes - Reconciliation of Tax Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/IncomeTaxesReconciliationofTaxRateDetails</Role>
      <ShortName>Income Taxes - Reconciliation of Tax Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>9955589 - Disclosure - Commitments and Contingencies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/CommitmentsandContingenciesDetails</Role>
      <ShortName>Commitments and Contingencies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/CommitmentsandContingencies</ParentRole>
      <Position>112</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>9955590 - Disclosure - Segment Data - Results of Operations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SegmentDataResultsofOperationsDetails</Role>
      <ShortName>Segment Data - Results of Operations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>113</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>9955591 - Disclosure - Segment Data - Balance Sheet (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SegmentDataBalanceSheetDetails</Role>
      <ShortName>Segment Data - Balance Sheet (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>114</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>9955592 - Disclosure - Segment Data - Additions to Long-lived Assets By Business Segment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SegmentDataAdditionstoLonglivedAssetsByBusinessSegmentDetails</Role>
      <ShortName>Segment Data - Additions to Long-lived Assets By Business Segment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>115</Position>
    </Report>
    <Report instance="stwd-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>9955593 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.starwoodpropertytrust.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.starwoodpropertytrust.com/role/SubsequentEvents</ParentRole>
      <Position>116</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="stwd-20260331.htm">stwd-20260331.htm</File>
    <File>stwd-20260331.xsd</File>
    <File>stwd-20260331_cal.xml</File>
    <File>stwd-20260331_def.xml</File>
    <File>stwd-20260331_lab.xml</File>
    <File>stwd-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="23">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="2683">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>
