3.25.4 html 488 637 1 false 151 0 false 19 false false R1.htm 0000001 - Document - Cover Sheet http://www.extraspace.com/role/Cover Cover Cover 1 false false R2.htm 0000002 - Document - Audit Information Sheet http://www.extraspace.com/role/AuditInformation Audit Information Cover 2 false false R3.htm 9952151 - Statement - Consolidated Balance Sheets Sheet http://www.extraspace.com/role/ConsolidatedBalanceSheets Consolidated Balance Sheets Statements 3 false false R4.htm 9952152 - Statement - Consolidated Balance Sheets (Parenthetical) Sheet http://www.extraspace.com/role/ConsolidatedBalanceSheetsParenthetical Consolidated Balance Sheets (Parenthetical) Statements 4 false false R5.htm 9952153 - Statement - Consolidated Statements of Operations Sheet http://www.extraspace.com/role/ConsolidatedStatementsofOperations Consolidated Statements of Operations Statements 5 false false R6.htm 9952154 - Statement - Consolidated Statements of Comprehensive Income Sheet http://www.extraspace.com/role/ConsolidatedStatementsofComprehensiveIncome Consolidated Statements of Comprehensive Income Statements 6 false false R7.htm 9952155 - Statement - Consolidated Statements of Stockholders??? Equity Sheet http://www.extraspace.com/role/ConsolidatedStatementsofStockholdersEquity Consolidated Statements of Stockholders??? Equity Statements 7 false false R8.htm 9952156 - Statement - Consolidated Statements of Stockholders??? Equity (Parenthetical) Sheet http://www.extraspace.com/role/ConsolidatedStatementsofStockholdersEquityParenthetical Consolidated Statements of Stockholders??? Equity (Parenthetical) Statements 8 false false R9.htm 9952157 - Statement - Consolidated Statements of Cash Flows Sheet http://www.extraspace.com/role/ConsolidatedStatementsofCashFlows Consolidated Statements of Cash Flows Statements 9 false false R10.htm 9952158 - Disclosure - Description of Business Sheet http://www.extraspace.com/role/DescriptionofBusiness Description of Business Notes 10 false false R11.htm 9952159 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 11 false false R12.htm 9952160 - Disclosure - Real Estate Assets Sheet http://www.extraspace.com/role/RealEstateAssets Real Estate Assets Notes 12 false false R13.htm 9952161 - Disclosure - Other Assets Sheet http://www.extraspace.com/role/OtherAssets Other Assets Notes 13 false false R14.htm 9952162 - Disclosure - Property Acquisitions and Dispositions Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositions Property Acquisitions and Dispositions Notes 14 false false R15.htm 9952163 - Disclosure - Investments in Unconsolidated Real Estate Entities Sheet http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntities Investments in Unconsolidated Real Estate Entities Notes 15 false false R16.htm 9952164 - Disclosure - Investments in Debt Securities and Notes Receivable Notes http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivable Investments in Debt Securities and Notes Receivable Notes 16 false false R17.htm 9952165 - Disclosure - Debt Sheet http://www.extraspace.com/role/Debt Debt Notes 17 false false R18.htm 9952166 - Disclosure - Derivatives Sheet http://www.extraspace.com/role/Derivatives Derivatives Notes 18 false false R19.htm 9952167 - Disclosure - Stockholders' Equity Sheet http://www.extraspace.com/role/StockholdersEquity Stockholders' Equity Notes 19 false false R20.htm 9952168 - Disclosure - Noncontrolling Interest Represented By Preferred Operating Partnership Units Sheet http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnits Noncontrolling Interest Represented By Preferred Operating Partnership Units Notes 20 false false R21.htm 9952169 - Disclosure - Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests Sheet http://www.extraspace.com/role/NoncontrollingInterestsInOperatingPartnershipandOtherNoncontrollingInterests Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests Notes 21 false false R22.htm 9952170 - Disclosure - Leases Sheet http://www.extraspace.com/role/Leases Leases Notes 22 false false R23.htm 9952171 - Disclosure - Stock-Based Compensation Sheet http://www.extraspace.com/role/StockBasedCompensation Stock-Based Compensation Notes 23 false false R24.htm 9952172 - Disclosure - Employee Benefit Plan Sheet http://www.extraspace.com/role/EmployeeBenefitPlan Employee Benefit Plan Notes 24 false false R25.htm 9952173 - Disclosure - Income Taxes Sheet http://www.extraspace.com/role/IncomeTaxes Income Taxes Notes 25 false false R26.htm 9952174 - Disclosure - Segment Information Sheet http://www.extraspace.com/role/SegmentInformation Segment Information Notes 26 false false R27.htm 9952175 - Disclosure - Commitments and Contingencies Sheet http://www.extraspace.com/role/CommitmentsandContingencies Commitments and Contingencies Notes 27 false false R28.htm 9952176 - Disclosure - Schedule III - Real Estate and Accumulated Depreciation Sheet http://www.extraspace.com/role/ScheduleIIIRealEstateandAccumulatedDepreciation Schedule III - Real Estate and Accumulated Depreciation Notes 28 false false R29.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 29 false false R30.htm 995447 - Disclosure - Insider Trading Policies and Procedures Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc Insider Trading Policies and Procedures Notes 30 false false R31.htm 995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure Sheet http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure Cybersecurity Risk Management and Strategy Disclosure Notes 31 false false R32.htm 9955511 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.extraspace.com/role/SummaryofSignificantAccountingPolicies 32 false false R33.htm 9955512 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://www.extraspace.com/role/SummaryofSignificantAccountingPolicies 33 false false R34.htm 9955513 - Disclosure - Real Estate Assets (Tables) Sheet http://www.extraspace.com/role/RealEstateAssetsTables Real Estate Assets (Tables) Tables http://www.extraspace.com/role/RealEstateAssets 34 false false R35.htm 9955514 - Disclosure - Other Assets (Tables) Sheet http://www.extraspace.com/role/OtherAssetsTables Other Assets (Tables) Tables http://www.extraspace.com/role/OtherAssets 35 false false R36.htm 9955515 - Disclosure - Property Acquisitions and Dispositions (Tables) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsTables Property Acquisitions and Dispositions (Tables) Tables http://www.extraspace.com/role/PropertyAcquisitionsandDispositions 36 false false R37.htm 9955516 - Disclosure - Investments in Unconsolidated Real Estate Entities (Tables) Sheet http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntitiesTables Investments in Unconsolidated Real Estate Entities (Tables) Tables http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntities 37 false false R38.htm 9955517 - Disclosure - Investments in Debt Securities and Notes Receivable (Tables) Notes http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivableTables Investments in Debt Securities and Notes Receivable (Tables) Tables http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivable 38 false false R39.htm 9955518 - Disclosure - Debt (Tables) Sheet http://www.extraspace.com/role/DebtTables Debt (Tables) Tables http://www.extraspace.com/role/Debt 39 false false R40.htm 9955519 - Disclosure - Derivatives (Tables) Sheet http://www.extraspace.com/role/DerivativesTables Derivatives (Tables) Tables http://www.extraspace.com/role/Derivatives 40 false false R41.htm 9955520 - Disclosure - Noncontrolling Interest Represented By Preferred Operating Partnership Units (Tables) Sheet http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnitsTables Noncontrolling Interest Represented By Preferred Operating Partnership Units (Tables) Tables http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnits 41 false false R42.htm 9955521 - Disclosure - Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests (Tables) Sheet http://www.extraspace.com/role/NoncontrollingInterestsInOperatingPartnershipandOtherNoncontrollingInterestsTables Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests (Tables) Tables http://www.extraspace.com/role/NoncontrollingInterestsInOperatingPartnershipandOtherNoncontrollingInterests 42 false false R43.htm 9955522 - Disclosure - Leases (Tables) Sheet http://www.extraspace.com/role/LeasesTables Leases (Tables) Tables http://www.extraspace.com/role/Leases 43 false false R44.htm 9955523 - Disclosure - Stock-Based Compensation (Tables) Sheet http://www.extraspace.com/role/StockBasedCompensationTables Stock-Based Compensation (Tables) Tables http://www.extraspace.com/role/StockBasedCompensation 44 false false R45.htm 9955524 - Disclosure - Income Taxes (Tables) Sheet http://www.extraspace.com/role/IncomeTaxesTables Income Taxes (Tables) Tables http://www.extraspace.com/role/IncomeTaxes 45 false false R46.htm 9955525 - Disclosure - Segment Information (Tables) Sheet http://www.extraspace.com/role/SegmentInformationTables Segment Information (Tables) Tables http://www.extraspace.com/role/SegmentInformation 46 false false R47.htm 9955526 - Disclosure - Description of Business (Details) Sheet http://www.extraspace.com/role/DescriptionofBusinessDetails Description of Business (Details) Details http://www.extraspace.com/role/DescriptionofBusiness 47 false false R48.htm 9955527 - Disclosure - Summary of Significant Accounting Policies - Variable Interest Entities (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesVariableInterestEntitiesDetails Summary of Significant Accounting Policies - Variable Interest Entities (Details) Details 48 false false R49.htm 9955528 - Disclosure - Summary of Significant Accounting Policies - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesScheduleofAssetsandLiabilitiesMeasuredatFairValueonaRecurringBasisDetails Summary of Significant Accounting Policies - Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) Details 49 false false R50.htm 9955529 - Disclosure - Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesAssetsandLiabilitiesMeasuredatFairValueonaNonrecurringBasisDetails Summary of Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis (Details) Details 50 false false R51.htm 9955530 - Disclosure - Summary of Significant Accounting Policies - Schedule of Fair Value of Financial Instruments (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesScheduleofFairValueofFinancialInstrumentsDetails Summary of Significant Accounting Policies - Schedule of Fair Value of Financial Instruments (Details) Details 51 false false R52.htm 9955531 - Disclosure - Summary of Significant Accounting Policies - Real Estate Assets (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesRealEstateAssetsDetails Summary of Significant Accounting Policies - Real Estate Assets (Details) Details 52 false false R53.htm 9955532 - Disclosure - Summary of Significant Accounting Policies - Risk Management and Use of Financial Instruments (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesRiskManagementandUseofFinancialInstrumentsDetails Summary of Significant Accounting Policies - Risk Management and Use of Financial Instruments (Details) Details 53 false false R54.htm 9955533 - Disclosure - Summary of Significant Accounting Policies - Revenue and Expense Recognition (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesRevenueandExpenseRecognitionDetails Summary of Significant Accounting Policies - Revenue and Expense Recognition (Details) Details 54 false false R55.htm 9955534 - Disclosure - Summary of Significant Accounting Policies - Advertising Costs (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesAdvertisingCostsDetails Summary of Significant Accounting Policies - Advertising Costs (Details) Details 55 false false R56.htm 9955535 - Disclosure - Summary of Significant Accounting Policies - Income Taxes (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesIncomeTaxesDetails Summary of Significant Accounting Policies - Income Taxes (Details) Details 56 false false R57.htm 9955536 - Disclosure - Summary of Significant Accounting Policies - Earnings Per Common Share (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesEarningsPerCommonShareDetails Summary of Significant Accounting Policies - Earnings Per Common Share (Details) Details 57 false false R58.htm 9955537 - Disclosure - Summary of Significant Accounting Policies - Schedule of Antidilutive Shares Excluded from Computation of Earnings Per Share (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesScheduleofAntidilutiveSharesExcludedfromComputationofEarningsPerShareDetails Summary of Significant Accounting Policies - Schedule of Antidilutive Shares Excluded from Computation of Earnings Per Share (Details) Details 58 false false R59.htm 9955538 - Disclosure - Summary of Significant Accounting Policies - Schedule of Computation of Earnings Per Common Share (Details) Sheet http://www.extraspace.com/role/SummaryofSignificantAccountingPoliciesScheduleofComputationofEarningsPerCommonShareDetails Summary of Significant Accounting Policies - Schedule of Computation of Earnings Per Common Share (Details) Details 59 false false R60.htm 9955539 - Disclosure - Real Estate Assets - Schedule of Components of Real Estate Assets (Details) Sheet http://www.extraspace.com/role/RealEstateAssetsScheduleofComponentsofRealEstateAssetsDetails Real Estate Assets - Schedule of Components of Real Estate Assets (Details) Details 60 false false R61.htm 9955540 - Disclosure - Real Estate Assets - Additional Information (Details) Sheet http://www.extraspace.com/role/RealEstateAssetsAdditionalInformationDetails Real Estate Assets - Additional Information (Details) Details 61 false false R62.htm 9955541 - Disclosure - Other Assets - Schedule of Other Assets (Details) Sheet http://www.extraspace.com/role/OtherAssetsScheduleofOtherAssetsDetails Other Assets - Schedule of Other Assets (Details) Details 62 false false R63.htm 9955542 - Disclosure - Other Assets - Narrative (Details) Sheet http://www.extraspace.com/role/OtherAssetsNarrativeDetails Other Assets - Narrative (Details) Details 63 false false R64.htm 9955543 - Disclosure - Property Acquisitions and Dispositions - Additional Information (Details) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsAdditionalInformationDetails Property Acquisitions and Dispositions - Additional Information (Details) Details 64 false false R65.htm 9955544 - Disclosure - Property Acquisitions and Dispositions - Asset Acquisition - Life Storage (Details) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsAssetAcquisitionLifeStorageDetails Property Acquisitions and Dispositions - Asset Acquisition - Life Storage (Details) Details 65 false false R66.htm 9955545 - Disclosure - Property Acquisitions and Dispositions - Asset Acquisition, Intangible Assets (Details) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsAssetAcquisitionIntangibleAssetsDetails Property Acquisitions and Dispositions - Asset Acquisition, Intangible Assets (Details) Details 66 false false R67.htm 9955546 - Disclosure - Property Acquisitions and Dispositions - Asset Acquisitions - Schedule of Operating Properties Acquired (Details) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsAssetAcquisitionsScheduleofOperatingPropertiesAcquiredDetails Property Acquisitions and Dispositions - Asset Acquisitions - Schedule of Operating Properties Acquired (Details) Details 67 false false R68.htm 9955547 - Disclosure - Property Acquisitions and Dispositions - Schedule of Held For Sale Activity (Details) Sheet http://www.extraspace.com/role/PropertyAcquisitionsandDispositionsScheduleofHeldForSaleActivityDetails Property Acquisitions and Dispositions - Schedule of Held For Sale Activity (Details) Details 68 false false R69.htm 9955548 - Disclosure - Investments in Unconsolidated Real Estate Entities - Schedule of Investments in Unconsolidated Real Estate Ventures (Details) Sheet http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntitiesScheduleofInvestmentsinUnconsolidatedRealEstateVenturesDetails Investments in Unconsolidated Real Estate Entities - Schedule of Investments in Unconsolidated Real Estate Ventures (Details) Details 69 false false R70.htm 9955549 - Disclosure - Investments in Unconsolidated Real Estate Entities - Schedule of Equity in Earnings of Unconsolidated Real Estate Ventures (Details) Sheet http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntitiesScheduleofEquityinEarningsofUnconsolidatedRealEstateVenturesDetails Investments in Unconsolidated Real Estate Entities - Schedule of Equity in Earnings of Unconsolidated Real Estate Ventures (Details) Details 70 false false R71.htm 9955550 - Disclosure - Investments in Unconsolidated Real Estate Entities - Additional Information (Details) Sheet http://www.extraspace.com/role/InvestmentsinUnconsolidatedRealEstateEntitiesAdditionalInformationDetails Investments in Unconsolidated Real Estate Entities - Additional Information (Details) Details 71 false false R72.htm 9955551 - Disclosure - Investments in Debt Securities and Notes Receivable - Schedule (Details) Notes http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivableScheduleDetails Investments in Debt Securities and Notes Receivable - Schedule (Details) Details http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivableTables 72 false false R73.htm 9955552 - Disclosure - Investments in Debt Securities and Notes Receivable - Additional Information (Details) Notes http://www.extraspace.com/role/InvestmentsinDebtSecuritiesandNotesReceivableAdditionalInformationDetails Investments in Debt Securities and Notes Receivable - Additional Information (Details) Details 73 false false R74.htm 9955553 - Disclosure - Debt - Schedule of Components of Term Debt (Details) Sheet http://www.extraspace.com/role/DebtScheduleofComponentsofTermDebtDetails Debt - Schedule of Components of Term Debt (Details) Details 74 false false R75.htm 9955554 - Disclosure - Debt - Schedule of Maturities of Notes Payable (Details) Notes http://www.extraspace.com/role/DebtScheduleofMaturitiesofNotesPayableDetails Debt - Schedule of Maturities of Notes Payable (Details) Details 75 false false R76.htm 9955555 - Disclosure - Debt - Additional Information (Details) Sheet http://www.extraspace.com/role/DebtAdditionalInformationDetails Debt - Additional Information (Details) Details 76 false false R77.htm 9955556 - Disclosure - Debt - Schedule of Information on Lines of Credit (Details) Sheet http://www.extraspace.com/role/DebtScheduleofInformationonLinesofCreditDetails Debt - Schedule of Information on Lines of Credit (Details) Details 77 false false R78.htm 9955557 - Disclosure - Derivatives - Additional Information (Details) Sheet http://www.extraspace.com/role/DerivativesAdditionalInformationDetails Derivatives - Additional Information (Details) Details 78 false false R79.htm 9955558 - Disclosure - Derivatives - Schedule Summarizing Terms of Entity's Derivative Financial Instruments (Details) Sheet http://www.extraspace.com/role/DerivativesScheduleSummarizingTermsofEntitysDerivativeFinancialInstrumentsDetails Derivatives - Schedule Summarizing Terms of Entity's Derivative Financial Instruments (Details) Details 79 false false R80.htm 9955559 - Disclosure - Derivatives - Schedule of Balance Sheet Classification and Fair Value of Entity's Derivative Financial Instruments (Details) Sheet http://www.extraspace.com/role/DerivativesScheduleofBalanceSheetClassificationandFairValueofEntitysDerivativeFinancialInstrumentsDetails Derivatives - Schedule of Balance Sheet Classification and Fair Value of Entity's Derivative Financial Instruments (Details) Details 80 false false R81.htm 9955560 - Disclosure - Derivatives - Schedule of Information Relating to Gain (Loss) Recognized on Swap Agreements (Details) Sheet http://www.extraspace.com/role/DerivativesScheduleofInformationRelatingtoGainLossRecognizedonSwapAgreementsDetails Derivatives - Schedule of Information Relating to Gain (Loss) Recognized on Swap Agreements (Details) Details 81 false false R82.htm 9955561 - Disclosure - Stockholders' Equity (Details) Sheet http://www.extraspace.com/role/StockholdersEquityDetails Stockholders' Equity (Details) Details http://www.extraspace.com/role/StockholdersEquity 82 false false R83.htm 9955562 - Disclosure - Noncontrolling Interest Represented By Preferred Operating Partnership Units - Preferred OP Units (Details) Sheet http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnitsPreferredOPUnitsDetails Noncontrolling Interest Represented By Preferred Operating Partnership Units - Preferred OP Units (Details) Details 83 false false R84.htm 9955563 - Disclosure - Noncontrolling Interest Represented By Preferred Operating Partnership Units - Narrative (Details) Sheet http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnitsNarrativeDetails Noncontrolling Interest Represented By Preferred Operating Partnership Units - Narrative (Details) Details http://www.extraspace.com/role/NoncontrollingInterestRepresentedByPreferredOperatingPartnershipUnitsTables 84 false false R85.htm 9955564 - Disclosure - Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests - Additional Information (Details) Sheet http://www.extraspace.com/role/NoncontrollingInterestsInOperatingPartnershipandOtherNoncontrollingInterestsAdditionalInformationDetails Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests - Additional Information (Details) Details 85 false false R86.htm 9955565 - Disclosure - Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests - Schedule of OP Unit Activity (Details) Sheet http://www.extraspace.com/role/NoncontrollingInterestsInOperatingPartnershipandOtherNoncontrollingInterestsScheduleofOPUnitActivityDetails Noncontrolling Interests In Operating Partnership and Other Noncontrolling Interests - Schedule of OP Unit Activity (Details) Details 86 false false R87.htm 9955566 - Disclosure - Leases - Additional Information (Details) Sheet http://www.extraspace.com/role/LeasesAdditionalInformationDetails Leases - Additional Information (Details) Details 87 false false R88.htm 9955567 - Disclosure - Leases - Lease Costs (Details) Sheet http://www.extraspace.com/role/LeasesLeaseCostsDetails Leases - Lease Costs (Details) Details 88 false false R89.htm 9955568 - Disclosure - Leases - Undiscounted Cash Flows on an Annual Basis (Details) Sheet http://www.extraspace.com/role/LeasesUndiscountedCashFlowsonanAnnualBasisDetails Leases - Undiscounted Cash Flows on an Annual Basis (Details) Details 89 false false R90.htm 9955569 - Disclosure - Stock-Based Compensation - Additional Information (Details) Sheet http://www.extraspace.com/role/StockBasedCompensationAdditionalInformationDetails Stock-Based Compensation - Additional Information (Details) Details 90 false false R91.htm 9955570 - Disclosure - Stock-Based Compensation - Summary of Stock Option Activity (Details) Sheet http://www.extraspace.com/role/StockBasedCompensationSummaryofStockOptionActivityDetails Stock-Based Compensation - Summary of Stock Option Activity (Details) Details 91 false false R92.htm 9955571 - Disclosure - Stock-Based Compensation - Summary of Employee and Director Share Grant Activity (Details) Sheet http://www.extraspace.com/role/StockBasedCompensationSummaryofEmployeeandDirectorShareGrantActivityDetails Stock-Based Compensation - Summary of Employee and Director Share Grant Activity (Details) Details 92 false false R93.htm 9955572 - Disclosure - Stock-Based Compensation - Summary of PSU Activity (Details) Sheet http://www.extraspace.com/role/StockBasedCompensationSummaryofPSUActivityDetails Stock-Based Compensation - Summary of PSU Activity (Details) Details 93 false false R94.htm 9955573 - Disclosure - Stock-Based Compensation - Assumptions Used to Calculate Fair Value of Awards (Details) Sheet http://www.extraspace.com/role/StockBasedCompensationAssumptionsUsedtoCalculateFairValueofAwardsDetails Stock-Based Compensation - Assumptions Used to Calculate Fair Value of Awards (Details) Details 94 false false R95.htm 9955574 - Disclosure - Employee Benefit Plan (Details) Sheet http://www.extraspace.com/role/EmployeeBenefitPlanDetails Employee Benefit Plan (Details) Details http://www.extraspace.com/role/EmployeeBenefitPlan 95 false false R96.htm 9955575 - Disclosure - Income Taxes - Income Tax Provision (Details) Sheet http://www.extraspace.com/role/IncomeTaxesIncomeTaxProvisionDetails Income Taxes - Income Tax Provision (Details) Details 96 false false R97.htm 9955576 - Disclosure - Income Taxes - Reconciliation of Statutory Income Tax Provision (Details) Sheet http://www.extraspace.com/role/IncomeTaxesReconciliationofStatutoryIncomeTaxProvisionDetails Income Taxes - Reconciliation of Statutory Income Tax Provision (Details) Details 97 false false R98.htm 9955577 - Disclosure - Income Taxes - Schedule of Income Tax Paid (Details) Sheet http://www.extraspace.com/role/IncomeTaxesScheduleofIncomeTaxPaidDetails Income Taxes - Schedule of Income Tax Paid (Details) Details 98 false false R99.htm 9955578 - Disclosure - Income Taxes - Sources of Temporary Differences (Details) Sheet http://www.extraspace.com/role/IncomeTaxesSourcesofTemporaryDifferencesDetails Income Taxes - Sources of Temporary Differences (Details) Details 99 false false R100.htm 9955579 - Disclosure - Segment Information - Additional Information (Details) Sheet http://www.extraspace.com/role/SegmentInformationAdditionalInformationDetails Segment Information - Additional Information (Details) Details 100 false false R101.htm 9955580 - Disclosure - Segment Information - Schedule of Financial Information of Business Segments (Details) Sheet http://www.extraspace.com/role/SegmentInformationScheduleofFinancialInformationofBusinessSegmentsDetails Segment Information - Schedule of Financial Information of Business Segments (Details) Details 101 false false R102.htm 9955581 - Disclosure - Commitments and Contingencies (Details) Sheet http://www.extraspace.com/role/CommitmentsandContingenciesDetails Commitments and Contingencies (Details) Details http://www.extraspace.com/role/CommitmentsandContingencies 102 false false R103.htm 9955582 - Disclosure - Schedule III - Real Estate and Accumulated Depreciation - Property Summary (Details) Sheet http://www.extraspace.com/role/ScheduleIIIRealEstateandAccumulatedDepreciationPropertySummaryDetails Schedule III - Real Estate and Accumulated Depreciation - Property Summary (Details) Details 103 false false R104.htm 9955583 - Disclosure - Schedule III - Real Estate and Accumulated Depreciation - Activity in Real Estate Facilities (Details) Sheet http://www.extraspace.com/role/ScheduleIIIRealEstateandAccumulatedDepreciationActivityinRealEstateFacilitiesDetails Schedule III - Real Estate and Accumulated Depreciation - Activity in Real Estate Facilities (Details) Details 104 false false All Reports Book All Reports exr-20251231.htm exr-20251231.xsd exr-20251231_cal.xml exr-20251231_def.xml exr-20251231_lab.xml exr-20251231_pre.xml exr-20251231_g1.jpg exr-20251231_g2.jpg http://fasb.org/srt/2025 http://fasb.org/us-gaap/2025 http://xbrl.sec.gov/cyd/2025 http://xbrl.sec.gov/dei/2025 http://xbrl.sec.gov/ecd/2025 true true