<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.26.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>263</ContextCount>
  <ElementCount>349</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>95</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>11</UnitCount>
  <MyReports>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0000001 - Document - Cover</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/Cover</Role>
      <ShortName>Cover</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>9952151 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>9952152 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>9952153 - Statement - Condensed Consolidated Statements of Operations and Comprehensive Income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CondensedConsolidatedStatementsofOperationsandComprehensiveIncome</Role>
      <ShortName>Condensed Consolidated Statements of Operations and Comprehensive Income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>9952154 - Statement - Condensed Consolidated Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CondensedConsolidatedStatementsofCashFlows</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>9952155 - Disclosure - Organization, Basis of Presentation and Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/OrganizationBasisofPresentationandSignificantAccountingPolicies</Role>
      <ShortName>Organization, Basis of Presentation and Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>9952156 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>9952157 - Disclosure - Real Estate and Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssets</Role>
      <ShortName>Real Estate and Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>9952158 - Disclosure - Real Estate Dispositions, Held for Sale and Impairment Charges</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentCharges</Role>
      <ShortName>Real Estate Dispositions, Held for Sale and Impairment Charges</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>9952159 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotes</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>9952160 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CommitmentsandContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>9952161 - Disclosure - Equity and Mezzanine Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquity</Role>
      <ShortName>Equity and Mezzanine Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>9952162 - Disclosure - Earnings Per Share of Common Stock</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EarningsPerShareofCommonStock</Role>
      <ShortName>Earnings Per Share of Common Stock</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>9952163 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/SubsequentEvents</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.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>15</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>9955511 - Disclosure - Organization, Basis of Presentation and Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/OrganizationBasisofPresentationandSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Organization, Basis of Presentation and Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/OrganizationBasisofPresentationandSignificantAccountingPolicies</ParentRole>
      <Position>16</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>9955512 - Disclosure - Real Estate and Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsTables</Role>
      <ShortName>Real Estate and Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssets</ParentRole>
      <Position>17</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>9955513 - Disclosure - Real Estate Dispositions, Held for Sale and Impairment Charges (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentChargesTables</Role>
      <ShortName>Real Estate Dispositions, Held for Sale and Impairment Charges (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentCharges</ParentRole>
      <Position>18</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>9955514 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesTables</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotes</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>9955515 - Disclosure - Commitments and Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CommitmentsandContingenciesTables</Role>
      <ShortName>Commitments and Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/CommitmentsandContingencies</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>9955516 - Disclosure - Equity and Mezzanine Equity (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquityTables</Role>
      <ShortName>Equity and Mezzanine Equity (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquity</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>9955517 - Disclosure - Earnings Per Share of Common Stock (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EarningsPerShareofCommonStockTables</Role>
      <ShortName>Earnings Per Share of Common Stock (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/EarningsPerShareofCommonStock</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>9955518 - Disclosure - Subsequent Events (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/SubsequentEventsTables</Role>
      <ShortName>Subsequent Events (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/SubsequentEvents</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>9955519 - Disclosure - Organization, Basis of Presentation and Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/OrganizationBasisofPresentationandSignificantAccountingPoliciesDetails</Role>
      <ShortName>Organization, Basis of Presentation and Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/OrganizationBasisofPresentationandSignificantAccountingPoliciesPolicies</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>9955520 - Disclosure - Related Party Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RelatedPartyTransactionsDetails</Role>
      <ShortName>Related Party Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/RelatedPartyTransactions</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>9955521 - Disclosure - Real Estate and Intangible Assets - Schedule of Components of Investments in Real Estate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofComponentsofInvestmentsinRealEstateDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Components of Investments in Real Estate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>9955522 - Disclosure - Real Estate and Intangible Assets - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsNarrativeDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>9955523 - Disclosure - Real Estate and Intangible Assets - Schedule of Acquired Properties (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofAcquiredPropertiesDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Acquired Properties (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>9955524 - Disclosure - Real Estate and Intangible Assets - Schedule of Fair Value of Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofFairValueofAssetsAcquiredandLiabilitiesAssumedDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Fair Value of Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>9955525 - Disclosure - Real Estate and Intangible Assets - Schedule of Future Operating Lease Payments from Tenants Under Non-Cancelable Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofFutureOperatingLeasePaymentsfromTenantsUnderNonCancelableLeasesDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Future Operating Lease Payments from Tenants Under Non-Cancelable Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>9955526 - Disclosure - Real Estate and Intangible Assets - Schedule of Allocation of Lease Revenue (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofAllocationofLeaseRevenueDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Allocation of Lease Revenue (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>9955527 - Disclosure - Real Estate and Intangible Assets - Sales-Type Leases (Narrative) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsSalesTypeLeasesNarrativeDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Sales-Type Leases (Narrative) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>9955528 - Disclosure - Real Estate and Intangible Assets - Schedule of Carrying Value of Intangible Assets, Liabilities and Accumulated Amortization (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofCarryingValueofIntangibleAssetsLiabilitiesandAccumulatedAmortizationDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Carrying Value of Intangible Assets, Liabilities and Accumulated Amortization (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>9955529 - Disclosure - Real Estate and Intangible Assets - Schedule of Weighted Average Amortization Period for Intangible Assets Acquired and Liabilities Assumed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateandIntangibleAssetsScheduleofWeightedAverageAmortizationPeriodforIntangibleAssetsAcquiredandLiabilitiesAssumedDetails</Role>
      <ShortName>Real Estate and Intangible Assets - Schedule of Weighted Average Amortization Period for Intangible Assets Acquired and Liabilities Assumed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>9955530 - Disclosure - Real Estate Dispositions, Held for Sale and Impairment Charges - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentChargesNarrativeDetails</Role>
      <ShortName>Real Estate Dispositions, Held for Sale and Impairment Charges - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentChargesTables</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>9955531 - Disclosure - Real Estate Dispositions, Held for Sale and Impairment Charges - Schedule of Properties Disposed (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentChargesScheduleofPropertiesDisposedDetails</Role>
      <ShortName>Real Estate Dispositions, Held for Sale and Impairment Charges - Schedule of Properties Disposed (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>9955532 - Disclosure - Real Estate Dispositions, Held for Sale and Impairment Charges - Schedule of Components of Assets and Liabilities Held for Sale (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/RealEstateDispositionsHeldforSaleandImpairmentChargesScheduleofComponentsofAssetsandLiabilitiesHeldforSaleDetails</Role>
      <ShortName>Real Estate Dispositions, Held for Sale and Impairment Charges - Schedule of Components of Assets and Liabilities Held for Sale (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>9955533 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Narrative (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesNarrativeDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesTables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>9955534 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Company's Mortgage Notes Payable and Credit Facility (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofCompanysMortgageNotesPayableandCreditFacilityDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Company's Mortgage Notes Payable and Credit Facility (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>9955535 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Long-Term Mortgages (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofLongTermMortgagesDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Long-Term Mortgages (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>9955536 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Principal Payments of Mortgage Notes Payable (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofPrincipalPaymentsofMortgageNotesPayableDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Principal Payments of Mortgage Notes Payable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>9955537 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Interest Rate Caps and Swaps (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofInterestRateCapsandSwapsDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Interest Rate Caps and Swaps (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>9955538 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Impact of Derivative Instruments (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofImpactofDerivativeInstrumentsDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Impact of Derivative Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>9955539 - Disclosure - Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Information Regarding Derivative Instruments (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/MortgageNotesPayableCreditFacilityandSeniorUnsecuredNotesScheduleofInformationRegardingDerivativeInstrumentsDetails</Role>
      <ShortName>Mortgage Notes Payable, Credit Facility, and Senior Unsecured Notes - Schedule of Information Regarding Derivative Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>9955540 - Disclosure - Commitments and Contingencies - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CommitmentsandContingenciesNarrativeDetails</Role>
      <ShortName>Commitments and Contingencies - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>9955541 - Disclosure - Commitments and Contingencies - Schedule of Future Minimum Rental Payments Due (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/CommitmentsandContingenciesScheduleofFutureMinimumRentalPaymentsDueDetails</Role>
      <ShortName>Commitments and Contingencies - Schedule of Future Minimum Rental Payments Due (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>9955542 - Disclosure - Equity and Mezzanine Equity - Schedule of Changes in Stockholders' Equity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquityScheduleofChangesinStockholdersEquityDetails</Role>
      <ShortName>Equity and Mezzanine Equity - Schedule of Changes in Stockholders' Equity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>9955543 - Disclosure - Equity and Mezzanine Equity - Schedule of Distributions Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquityScheduleofDistributionsPerShareDetails</Role>
      <ShortName>Equity and Mezzanine Equity - Schedule of Distributions Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>9955544 - Disclosure - Equity and Mezzanine Equity - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EquityandMezzanineEquityNarrativeDetails</Role>
      <ShortName>Equity and Mezzanine Equity - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>49</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>9955545 - Disclosure - Earnings Per Share of Common Stock (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/EarningsPerShareofCommonStockDetails</Role>
      <ShortName>Earnings Per Share of Common Stock (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/EarningsPerShareofCommonStockTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="good-20260331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>9955546 - Disclosure - Subsequent Events (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://ir.gladstonecommercial.com/role/SubsequentEventsDetails</Role>
      <ShortName>Subsequent Events (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://ir.gladstonecommercial.com/role/SubsequentEventsTables</ParentRole>
      <Position>51</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File doctype="10-Q" isDefinitelyFs="true" isUsgaap="true" original="good-20260331.htm">good-20260331.htm</File>
    <File>good-20260331.xsd</File>
    <File>good-20260331_cal.xml</File>
    <File>good-20260331_def.xml</File>
    <File>good-20260331_lab.xml</File>
    <File>good-20260331_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="1">http://fasb.org/srt/2025</BaseTaxonomy>
    <BaseTaxonomy items="658">http://fasb.org/us-gaap/2025</BaseTaxonomy>
    <BaseTaxonomy items="36">http://xbrl.sec.gov/dei/2025</BaseTaxonomy>
    <BaseTaxonomy items="11">http://xbrl.sec.gov/ecd/2025</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
