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Percentage of hotel occupancy gross revenue paid for program fee Percentage Of Hotel Occupancy Gross Revenue Paid For Program Fee Percentage of hotel occupancy gross revenue paid for program fee. Local Phone Number Local Phone Number Number of States Number Of State With Office, Retail, And Mixed-Use Properties Number Of State With Office, Retail, And Mixed-Use Properties Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Purchase price seller credits, future rent abatement Purchase Price Seller Credits, Future Rent Abatement Purchase Price Seller Credits, Future Rent Abatement Other Other Debt [Member] Other Debt Notional Amount Derivative, Notional Amount Improvements SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Improvements Measurement Frequency [Axis] Measurement Frequency [Axis] Senior Guaranteed Notes, Series F Senior Guaranteed Notes, Series F [Member] Senior Guaranteed Notes, Series F [Member] Forfeiture of restricted units (in shares) Partners' Capital Account, Restricted Units Forfeiture Partners' Capital Account, Restricted Units Forfeiture Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Summary of Activity of Restricted Stock Awards Share-Based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Real estate assets SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate [Roll Forward] Real estate depreciation expense Depreciation Lessor, Lease, Description [Table] Lessor, Lease, Description [Table] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Years in hotel management agreement term Term Period For Termination Of Agreement Term period for termination of agreement. Shares withheld for employee taxes Units withheld for employee taxes Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Summary of Purchase Price Allocation Schedule of Business Acquisitions, by Acquisition [Table Text Block] Cash balance at banks, excess of FDIC insured limit Cash, Uninsured Amount Capital Expenditures Capital Expenditures and Leasing Commissions Capital Expenditures And Leasing Commissions Management fees Management Fee Expense Variable Interest Entities Consolidation, Variable Interest Entity, Policy [Policy Text Block] Total revenue Revenues Revenues Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Antidilutive securities excluded from computation of EPS (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Award Type [Axis] Award Type [Axis] Granted, Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Supplemental schedule of noncash investing and financing activities Noncash Investing and Financing Items [Abstract] The aggregate tax basis for Federal tax purposes SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Federal Income Tax Basis Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Quarterly Financial Information [Table] Quarterly Financial Information [Table] Quarterly Financial Information [Table] Hedging Designation [Axis] Hedging Designation [Axis] Percentage annual distributions cannot exceed funds from operations Percentage Limit On Annual Distributions In Relation To Funds From Operations Percentage limit on annual distributions in relation to funds from operations. 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Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Award vesting rights Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage Employee Stock Option Employee Stock Option [Member] DERIVATIVE AND HEDGING ACTIVITIES Derivative Instruments and Hedging Activities Disclosure [Text Block] Interest rate swap liability Interest Rate Derivative Liabilities, at Fair Value Total operating expenses Operating expenses Costs and Expenses Maximum Maximum [Member] Number of sales agents Number of Sales Agents Number of Sales Agents Summary of Interest Rate Swap Terms Schedule of Interest Rate Derivatives [Table Text Block] Document Type Document Type Solana Beach Towne Centre Solana Beach Towne Centre [Member] Solana Beach towne centre. Weighted average interest rate Line of Credit Facility, Interest Rate During Period Tabular List, Table Tabular List [Table Text Block] Retail Or Office Retail Or Office [Member] Retail Or Office Year of Agreement, 15th Future Year Period Four [Member] Future year period four. Thereafter Long-Term Debt, Maturity, after Year Five City Center Bellevue City Center Bellevue [Member] City center bellevue. Property expense Property Expenses Property expenses. Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Capitalized Costs Capitalization of Internal Costs, Policy [Policy Text Block] Other non-operating income (expense) Other Non-Operating Income (Expense), Other Other Non-Operating Income (Expense), Other Summary Of Significant Accounting Policies Summary Of Significant Accounting Policies [Table] Summary Of Significant Accounting Policies [Table] Federal Current Federal Tax Expense (Benefit) Other, net Other Noncash Income (Expense) Property management fee, percent Property Management Fee, Percent Fee Torrey Plaza Torrey Plaza [Member] Torrey Plaza [Member] Retail Total Retail Retail Segment [Member] Retail Segment. Leases Lease Agreements [Member] Customer Concentration Risk Customer Concentration Risk [Member] Interest Rate Swap, 1/5/2027 Interest Rate Swap, 1/5/2027 [Member] Interest Rate Swap, 1/5/2027 State Deferred State and Local Income Tax Expense (Benefit) Real Estate [Table] Real Estate [Table] Variable Rate [Axis] Variable Rate [Axis] Change in accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Minimum base rate Debt Instrument, Variable Rate Basis, Four Debt Instrument, Variable Rate Basis, Four 2024 Lessor, Operating Lease, Payment to be Received, Year One Property revenue Revenue from Contract with Customer, Including Assessed Tax Title of 12(b) Security Title of 12(b) Security Related Party, Type [Domain] Related Party, Type [Domain] Sublease income Sublease Income Incremental stock compensation cost from modification Share-Based Payment Arrangement, Plan Modification, Incremental Cost Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Percentage of ownership interests classified as noncontrolling Subsidiary, Ownership Percentage, Noncontrolling Owner Nonvested, Beginning, Weighted Average Grant Date Fair Value (in USD per Share) Nonvested, End of Year, Weighted Average Grant Date Fair Value (in USD per Share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Environmental remediation monitoring period Site Contingency, Environmental Remediation Monitoring Period Site Contingency, Environmental Remediation Monitoring Period Fixed interest rate on derivative Derivative, Fixed Interest Rate Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Revenue Recognition and Accounts Receivable Revenue Recognition, Leases [Policy Text Block] Accumulated depreciation Real Estate Investment Property, Accumulated Depreciation Entity Tax Identification Number Entity Tax Identification Number La Jolla Commons One & Two La Jolla Commons One & Two [Member] La Jolla Commons I & II Effect of dilutive securities-conversion of Operating Partnership units (in shares) Incremental Common Shares Attributable To Conversion Of Operating Partnership Units Incremental common shares attributable to conversion of Operating partnership units. SCHEDULE III-Consolidated Real Estate and Accumulated Depreciation SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation Disclosure [Text Block] $250.0 Million ATM $250.0 Million ATM [Member] $250.0 Million ATM [Member] Purchase of marketable securities Payments to Acquire Marketable Securities Statistical Measurement [Axis] Statistical Measurement [Axis] Entity Interactive Data Current Entity Interactive Data Current 2025 Below Market Lease, Amortization Income, Year Two Adjustments to reconcile net income to net cash provided by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Term of lease Lessor, Operating Lease, Term of Contract Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Bank of America, N.A. Bank Of America, N.A. [Member] Bank Of America, N.A. Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Mixed-Use Total Mixed-Use Mixed Use Segment [Member] Mixed Use Segment [Member] Interest Rate Swap, Year One Interest Rate Swap, Year One [Member] Interest Rate Swap, Year One Measure: Measure [Axis] ATM Equity Program [Axis] ATM Equity Program [Axis] Information on ATM Equity Program [Axis] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Name Outstanding Recovery, Individual Name Year of Agreement, 13th Future Year Period Two [Member] Future year period two. Maximum secured leverage ratio on revolving credit facility Maximum Secured Leverage Ratio On Revolving Credit Facility Maximum Secured Leverage Ratio On Revolving Credit Facility Term Loan A Term Loan A [Member] Term Loan A [Member] Auditor [Line Items] Auditor [Line Items] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Eastgate Office Park Eastgate Office Park [Member] Eastgate Office Park Counterparty Name [Axis] Counterparty Name [Axis] Initial Cost, Building and Improvements SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Initial Cost of Building and Improvements Rental Income Rental Income [Member] Rental Income [Member] Derivative Instruments Derivatives, Policy [Policy Text Block] Schedule of Related Party Transactions, by Related Party Schedule of Related Party Transactions, by Related Party [Table] Year of Agreement, 12th Future Year Period One [Member] Future year period one. 2024 Finite-Lived Intangible Asset, Expected Amortization, Year One Cash paid for amounts included in the measurement of lease liabilities Operating Lease, Payments DENOMINATOR Computation Of Basic And Diluted Earnings Per Share Denominator [Abstract] Computation of basic and diluted earnings per share denominator. Common stock, shares outstanding (in shares) Beginning Balance (shares) Ending Balance (shares) Common Stock, Shares, Outstanding Other Income and Expenses [Abstract] Other Income and Expenses [Abstract] PEO PEO [Member] Environmental Remediation Site [Domain] Environmental Remediation Site [Domain] Minimum Future Rentals From Noncancelable Operating Leases Lessor, Operating Lease, Payment to be Received, Maturity [Table Text Block] Auditor Location Auditor Location Term of office and retail leases Term of Office and Retail Leases Term of office and retail leases. Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Marketing Marketing Expense Sale of Stock [Axis] Sale of Stock [Axis] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Senior Guaranteed Notes, Series B Senior Guaranteed Notes, Series B [Member] Senior Guaranteed Notes, Series B Below market leases Below Market Lease, Gross Change in security deposits payable Increase (Decrease) In Security Deposits Payable Increase (Decrease) In Security Deposits Payable Interest Rate Swap Interest Rate Swap [Member] Debt Instrument [Axis] Debt Instrument [Axis] Pacific South Court Pacific South Court [Member] Pacific South Court [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Waikiki Beach Walk - Retail Waikiki Beach Walk Retail [Member] Waikiki Beach walk retail. Credit Facility [Axis] Credit Facility [Axis] Scheduled Principal Payments on Notes Payable Schedule of Maturities of Long-Term Debt [Table Text Block] Total liabilities Liabilities assumed Liabilities Environmental Remediation Site [Axis] Environmental Remediation Site [Axis] EQUITY OF AMERICAN ASSETS TRUST, INC. Shareholders' Equity and Share-Based Payments [Text Block] Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] Measurement Frequency [Domain] Measurement Frequency [Domain] Senior Guaranteed Notes, Series A Senior Guaranteed Notes, Series A [Member] aat_SeniorGuaranteedNotes,SeriesA 2026 Lessor, Operating Lease, Payment to be Received, Year Three Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Property, Plant and Equipment, Type [Domain] Long-Lived Tangible Asset [Domain] Subsequent Event [Line Items] Subsequent Event [Line Items] Gross Carrying Amount, Building and Improvements SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Building and Improvements, Amount Torrey Point Torrey Point [Member] Torrey Point [Member] General and administrative General and administrative General and Administrative Expense Net income attributable to unitholders in the Operating Partnership Less: Income attributable to unitholders in the Operating Partnership Noncontrolling Interest in Net Income (Loss) Operating Partnerships, Redeemable Capital expenditures Payments for Capital Improvements Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] State Current State and Local Tax Expense (Benefit) Segment Information Segment Reporting, Policy [Policy Text Block] Carmel Country Plaza Carmel Country Plaza [Member] Carmel Country Plaza [Member] General excise tax recognized, gross Excise Taxes Collected Supplemental cash flow information Supplemental Cash Flow Information [Abstract] Aggregate offering price of common share Aggregate Offering Price Of Common Share Maximum aggregate offering price of common shares. Total rental expenses Rental Expense, Operating Expense Rental Expense, Operating Expense Other liabilities Other Liabilities First period Interest Rate, Year One [Member] Interest Rate, Year One Percentage of total revenue provided by properties Concentration Risk, Percentage Years of contract Years Of Contract Years of contract. Encumbrance as of December 31, 2023 SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Amount of Encumbrances American Assets Trust, L.P. American Assets Trust, L.P. [Member] American Assets Trust, L.P. [Member] Quarterly Financial Information Disclosure [Abstract] Quarterly Financial Information Disclosure [Abstract] Granted (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value 2028 Finite-Lived Intangible Asset, Expected Amortization, Year Five Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Forward Contracts Forward Contracts [Member] Summary of Future Amortization for Acquired In-Place Leases Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Forfeiture of restricted stock Stock Issued During Period, Value, Restricted Stock Award, Forfeitures Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Unsecured notes payable, net Total Unsecured Notes Payable Unsecured Debt Leasing commissions, net of accumulated amortization of $47,978 and $43,078, respectively Deferred Costs, Leasing, Net Depreciation and amortization Depreciation, Depletion and Amortization Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Number of employees Entity Number of Employees At The Market Equity Program At The Market Equity Program [Member] At The Market Equity Program [Member] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Restricted cash Restricted Cash and Cash Equivalents Del Monte Center Del Monte Center [Member] Del Monte Center. Provision for uncollectable rental income Net Investment in Lease, Credit Loss Expense (Reversal) Finite-Lived Intangible Assets Acquired as Part of Business Combination Finite-Lived Intangible Assets Acquired as Part of Business Combination [Table] Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Depreciation and amortization Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued OTHER ASSETS Other Assets Disclosure [Text Block] Accounts payable and accrued liabilities for construction in progress Increase (Decrease) Accrued Construction In Progress Change in accrued liabilities for construction in progress. Other liabilities and deferred credits Other liabilities and deferred credits Total other liabilities and deferred credits, net Deferred Credits and Other Liabilities Entity Emerging Growth Company Entity Emerging Growth Company Debt issuance costs, net of accumulated amortization of $1,296 and $0, respectively Debt issuance costs, net of accumulated amortization of $542 and $452, respectively Debt discount and issuance costs, net of accumulated amortization of $7,259 and $11,709, respectively Debt issuance costs Debt Issuance Costs, Net Weighted average unvested shares outstanding (in shares) Weighted Average Unvested Participating Securities Outstanding Weighted average unvested participating securities outstanding. COMPONENTS OF RENTAL INCOME AND EXPENSE Components Of Rental Income And Expense [Text Block] The entire disclosure of the principle components of rental income and/or rental expense recognized for the period. Ordinary income Ordinary Income Dividends Percentage Ordinary Income, Dividends, Percentage American Assets, Inc. American Assets, Inc. [Member] American Assets, Inc. [Member] 2024 Lessee, Operating Lease, Liability, to be Paid, Year One Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Title Trading Arrangement, Individual Title Properties owned through noncontrolling interest Number Of Properties Owned Through Noncontrolling Interests In Entities Number Of Properties Owned Through Noncontrolling Interests In Entities Common Shares Common Stock [Member] Individual: Individual [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Straight-line rent liability Deferred Rent Credit Income Statement Location [Domain] Income Statement Location [Domain] Repayment of secured notes payable Repayments of Secured Debt Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Total equity Beginning balance Ending balance Equity, Including Portion Attributable to Noncontrolling Interest PARTNERS' CAPITAL OF AMERICAN ASSETS TRUST, L.P. Partners' Capital Notes Disclosure [Text Block] Minimum Minimum [Member] Proceeds from legal settlements Net settlement payment Proceeds from Legal Settlements Amount per Share/Unit (in dollars per unit) Total (in dollars per share) Common Stock, Dividends, Per Share, Cash Paid Area of real estate property Area of Real Estate Property Number of office, retail, multifamily and mixed-use operating properties Number of Real Estate Properties Reclassified within twelve months Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] ASSETS Assets [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] LPL Holdings, Inc., Autodesk, Inc., and Smartsheet, Inc. LPL Holdings, Inc., Autodesk, Inc., and Smartsheet, Inc. [Member] LPL Holdings, Inc., Autodesk, Inc., and Smartsheet, Inc. Total Revenue Total Revenue [Member] Total Revenue [Member] In-place leases Leases, Acquired-in-Place [Member] Shares withheld for employee taxes Payment, Tax Withholding, Share-Based Payment Arrangement LIABILITIES: Liabilities [Abstract] Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Accumulated Dividends in Excess of Net Income Retained Earnings [Member] Torrey Reserve Building 13 & 14 Torrey Reserve Building 13 & 14 [Member] Torrey Reserve Building 13 & 14 [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Basic income attributable to common stockholders per share (in USD per share) Earnings per unit, basic (in USD per share) Net income per share attributable to common stockholders - basic (in USD per share) Earnings Per Share, Basic Accumulated depreciation SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation [Roll Forward] Accounting Policies [Abstract] Accounting Policies [Abstract] Sale of Stock [Domain] Sale of Stock [Domain] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Alamo Quarry Market and Waikele Center Alamo Quarry Market and Waikele Center [Member] Alamo Quarry Market and Waikele Center [Member] Maximum leverage ratio of revolving credit facility Line Of Credit Facility Maximum Leverage Percentage Maximum leverage percentage of revolving credit facility. Investment in WBW CHP LLC, in percentage Percentage Of Investment In Related Party Percentage of investment in related party. AAI Aviation, Inc. AAI Aviation, Inc. [Member] AAI Aviation Inc [Member] Years in hotel management agreement term Years In Hotel Management Agreement Term Years in hotel management agreement term. Rental operating Direct Costs of Leased Property, Lessor, Expense Direct Costs of Leased Property, Lessor, Expense Noncash compensation expense Restricted Stock or Unit Expense Cash paid for income taxes Income Taxes Paid Basis of Presentation Consolidation, Policy [Policy Text Block] Purchase Commitment, Excluding Long-term Commitment [Domain] Purchase Commitment, Excluding Long-Term Commitment [Domain] Dividends declared and paid Adjustments to Additional Paid in Capital, Dividends in Excess of Retained Earnings Real Estate and Accumulated Depreciation [Line Items] SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation [Line Items] Document Transition Report Document Transition Report Award Timing Predetermined Award Timing Predetermined [Flag] Net real estate Net real estate Real Estate Investment Property, Net Unsecured Debt Unsecured Debt [Member] Secured Overnight Financing Rate Secured Overnight Financing Rate [Member] Secured Overnight Financing Rate Repayment of unsecured line of credit Repayment of unsecured line of credit Repayments of Lines of Credit Minimum fixed charge coverage ratio covenant threshold Minimum Fixed Charge Coverage Ratio On Revolving Credit Facility Minimum Fixed Charge Coverage Ratio On Revolving Credit Facility Entity Public Float Entity Public Float Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Land improvements Land Improvements Other Liabilities Disclosure [Abstract] Other Liabilities Disclosure [Abstract] Derivative Instrument [Axis] Derivative Instrument [Axis] Principal balance Principal Balance as of Long-Term Debt, Gross Security deposits payable Security deposits payable Security Deposit Liability All Trading Arrangements All Trading Arrangements [Member] All Adjustments to Compensation All Adjustments to Compensation [Member] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Limited partners' capital, 16,181,537 and 16,181,537 units issued and outstanding as of December 31, 2023 and December 31, 2022, respectively Limited Partners' Capital Account Compensation Amount Outstanding Recovery Compensation Amount Interest and investment income Interest and Other Income Rental Income Rental Income [Table] Rental Income [Table] Pacific Torrey Daycare Pacific Torrey Daycare [Member] Pacific Torrey Daycare [Member] NUMERATOR Computation Of Basic And Diluted Earnings Per Share Numerator [Abstract] Computation of basic and diluted earnings per share numerator. Total bad debt expense Accounts Receivable, Credit Loss Expense (Reversal) Interest rate swap asset Derivative Asset Forfeited (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Issuance of restricted stock Stock Issued During Period, Value, Restricted Stock Award, Gross Subsequent Event Type [Axis] Subsequent Event Type [Axis] Schedule of Reconciliation of Segment Profit to Net Income Attributable to Stockholders Reconciliation Of Segment Profit To Net Income Attributable To Stockholders Table [Table Text Block] Reconciliation of segment profit to net income attributable to stockholders. 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Partial debt repayment, minimum percentage of principal Debt Instrument, Partial Repayment, Minimum Percentage of Principal Debt Instrument, Partial Repayment, Minimum Percentage of Principal Operating lease cost Operating Lease, Cost Hotel management agreement default penalty factor of previous twelve months of management fees in fifteenth year of term Hotel Management Agreement Default Penalty Factor Of Previous Twelve Months Of Management Fees In Fifteenth Year Of Term Hotel management agreement default penalty factor of previous twelve months of Management fees in fifteenth year of term. Impairment of Long Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Common stock, shares issued (in shares) Common Stock, Shares, Issued Lease extension options exercise period Lease Extension Options Exercise Period The period which lease extension options can be exercisable. 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[Member] ATM Equity Program [Domain] ATM Equity Program [Domain] [Domain] for Information on ATM Equity Program [Axis] Ownership percent by parent Subsidiary, Ownership Percentage, Parent Derivative, Interest Rate Period [Axis] Derivative, Interest Rate Period [Axis] Derivative, Interest Rate Period Held for development Land Available for Development Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Subsequent Event Subsequent Event [Member] Income Statement [Abstract] Income Statement [Abstract] Common shares issued (in shares) Stock Issued During Period, Shares, New Issues Other SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation, Other Deduction One Beach Street One Beach Street [Member] One Beach Street. 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Property acquisitions SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Other Acquisition Change in other liabilities and deferred credits Increase (Decrease) in Other Deferred Liability Amortization of leases Operating Lease, Right-of-Use Asset, Periodic Reduction EDisability, LLC EDisability, LLC [Member] EDisability, LLC [Member] Loma Palisades Loma Palisades [Member] Loma palisades. 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Summary of Principal Components of Rental Income Components Of Rental Income Table [Table Text Block] Components of rental income. Other SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Other Deduction Balance, beginning of period Balance, end of period SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Gross Exercise Price Award Exercise Price Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Year of Agreement, 14th Future Year Period Three [Member] Future year period three. Deferred compensation liability Liabilities, Fair Value Disclosure Other property income Other Operating Income Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Net income Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Thereafter Lessor, Operating Lease, Payment to be Received, after Year Five Look-back period Measurement Input, Volatility, Look Back Period Measurement Input, Volatility, Look Back Period Federal Funds Rate Federal Funds Rate [Member] Interest based on Federal Funds Rate. Weighted-average amortization period of acquired leases Acquired Finite-Lived Intangible Asset, Weighted-Average Period before Renewal or Extension Schedule of Segments Operating Activity Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] TOTAL LIABILITIES AND EQUITY Liabilities and Equity Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Ownership [Domain] Ownership [Domain] Right-of-use lease asset, net Operating Lease, Right-of-Use Asset Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Total Revenues, Property Total Revenues, Property [Member] Total Revenues, Property Net income attributable to common stockholders—diluted Net Income (Loss) Available to Common Stockholders, Diluted Arrangement Duration Trading Arrangement Duration Hawaii HAWAII Entity Address, City or Town Entity Address, City or Town Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Related Party Related Party [Member] Recognition of straight-line rents Straight Line Rent Partner Capital Components [Axis] Partner Capital Components [Axis] Forward starting swaps included in interest expense, net Forward Starting Swap, Interest Expense, Net [Member] Forward Starting Swap, Interest Expense, Net Purchase price seller credits, contractual tenant improvements Purchase Price Seller Credits, Contractual Tenant Improvements Purchase Price Seller Credits, Contractual Tenant Improvements Financial Instruments Fair Value of Financial Instruments, Policy [Policy Text Block] Derivative Instruments and Hedging Activities Disclosures [Table] Derivative Instruments and Hedging Activities Disclosures [Table] Termination Date Trading Arrangement Termination Date Initial Cost, Land SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Initial Cost of Land Furniture, fixtures, and equipment Furniture and Fixtures, Gross Sale of marketable securities Proceeds from Sale and Maturity of Marketable Securities Common stock, shares authorized (in shares) Common Stock, Shares Authorized Second Amended and Restated Credit Facility Second Amended and Restated Credit Facility [Member] Second Amended and Restated Credit Facility [Member] Document Information [Table] Document Information [Table] Lloyd District Portfolio Lloyd District Portfolio [Member] Lloyd District Portfolio. Percentage of taxable income required to distribute to qualify as real estate investment trust (REIT) Percentage Of Distributed Taxable Income To Qualify As Reit Percentage Of Distributed Taxable Income To Qualify As Reit Acquired lease, below market renewal options Finite-Lived Intangible Liabilities, Below Market Leases, Renewal Options Finite-Lived Intangible Liabilities, Below Market Leases, Renewal Options Related Party Transactions [Abstract] Related Party Transactions [Abstract] Hotel management agreement default penalty factor of previous twelve months of management fees in fourteenth year of term Hotel Management Agreement Default Penalty Fact Or Of Previous Twelve Months Of Management Fees In Fourteenth Year Of Term Hotel management agreement default penalty fact or of previous twelve months of Management fees in fourteenth year of term. Award Timing Disclosures [Line Items] Maximum unsecured leverage ratio (in percentage) Maximum Unsecured Leverage Ratio Maximum Unsecured Leverage Ratio La Jolla Commons - Land La Jolla Commons - Land [Member] La Jolla Commons - Land [Member] Thereafter Below Market Lease, Amortization Income, after Year Five Comprehensive income attributable to noncontrolling interest Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Auditor [Table] Auditor [Table] Number of existing buildings Number Of Existing Building Number Of Existing Building Document Information [Line Items] Document Information [Line Items] Mr. Rady And Affiliates Mr. Rady And Affiliates [Member] Mr. Rady And Affiliates Share-Based Payment Arrangement, Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Income Taxes Income Tax, Policy [Policy Text Block] 2026 Finite-Lived Intangible Asset, Expected Amortization, Year Three Insider Trading Arrangements [Line Items] Related Party, Type [Axis] Related Party, Type [Axis] Termination payment, as high as Loss on Contract Termination for Default Entity Registrant Name Entity Registrant Name Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Award Timing Method Award Timing Method [Text Block] Change in other assets Increase (Decrease) in Other Operating Assets 2025 Finite-Lived Intangible Asset, Expected Amortization, Year Two Adjustment to Compensation, Amount Adjustment to Compensation Amount Hassalo on Eighth - Retail Hassalo on Eighth - Retail [Member] Hassalo on Eighth - Retail [Member] Share-Based Payment Arrangement, Tranche Two Share-Based Payment Arrangement, Tranche Two [Member] CAPITAL: Partners' Capital [Abstract] Noncontrolling interests Equity, Attributable to Noncontrolling Interest Auditor Name Auditor Name Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Partner Type of Partners' Capital Account, Name [Domain] Partner Type of Partners' Capital Account, Name [Domain] Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Summary of Financial Liabilities Measured at Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Entity Central Index Key Entity Central Index Key Leasing commissions accumulative amortization Deferred Costs, Leasing, Accumulated Amortization Summary of Principal Components of Rental Expenses Components Of Rental Expense Table [Table Text Block] Components of rental expense. Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract] Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract] Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Environmental Remediation Contingency [Domain] Environmental Remediation Contingency [Domain] Acquired lease intangible assets Finite-Lived Intangible Asset, off-Market Lease, Favorable, Gross Maximum Recourse Indebtedness Of Total Asset Value Maximum Recourse Indebtedness Of Total Asset Value Maximum Recourse Indebtedness Of Total Asset Value Revenue Benchmark Revenue Benchmark [Member] Name Trading Arrangement, Individual Name Lessor, Lease, Description [Line Items] Lessor, Lease, Description [Line Items] Carmel Mountain Plaza Carmel Mountain Plaza [Member] Carmel Mountain Plaza [Member] Accumulated Depreciation and Amortization Balance, beginning of period Balance, end of period SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation Hotel revenue Revenue from Contract with Customer, Excluding Assessed Tax Entity [Domain] Entity [Domain] Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Amendment Flag Amendment Flag ACQUIRED IN-PLACE LEASES AND ABOVE/BELOW MARKET LEASES Intangible Assets Disclosure [Text Block] Legal Entity [Axis] Legal Entity [Axis] Weighted average yield of investment Debt Securities, Held-to-Maturity, Weighted Average Yield, Maturity, after Year 10 COMPREHENSIVE INCOME Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Weighted-average discount rate - operating leases (as a percent) Operating Lease, Weighted Average Discount Rate, Percent Cash paid for interest, net of amounts capitalized Interest Paid, Excluding Capitalized Interest, Operating Activities Imperial Beach Gardens Imperial Beach Gardens [Member] Imperial Beach Gardens. Weighted average shares of common stock outstanding-diluted (in shares) Weighted average units outstanding - diluted (in shares) Weighted average common shares outstanding - diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Amortization of acquired above and below market leases Recognition of amortization of above and below market leases Amortization of above and below Market Leases Interest expense, net Interest expense, net Interest expense, net Interest Income (Expense), Nonoperating, Net American Assets Trust, Inc. American Assets Trust, Inc. [Member] American Assets Trust, Inc. Percentage rent Operating Lease, Variable Lease Income Company Selected Measure Amount Company Selected Measure Amount Performance period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Performance Period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Performance Period Furniture And Equipment Furniture And Equipment [Member] Furniture And Equipment [Member] Above market leases Above Market Leases [Member] TOTAL ASSETS Assets Name Awards Close in Time to MNPI Disclosures, Individual Name Deferred rent revenue and amortization of lease intangibles Deferred Rent Revenue And Amortization Of Lease Intangibles The increase (decrease) during the reporting period in the amount due that is the result of the cumulative difference between actual rent due and rental income recognized on a straight-line basis. Also includes the amortization of lease intangibles. Waikiki Beach Walk Hotel Waikiki Beach Walk Hotel [Member] Waikiki Beach Walk Hotel [Member] Stock-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Rental expenses Cost of Other Property Operating Expense 2028 Long-Term Debt, Maturity, Year Five OTHER LIABILITIES AND DEFERRED CREDITS Other Liabilities Disclosure [Text Block] Vested (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Non-NEOs Non-NEOs [Member] Note offering percent Note Offering Percent Note Offering Percent Note Purchase Agreement Note Purchase Agreement [Member] Note Purchase Agreement [Member] FINANCING ACTIVITIES Net Cash Provided by (Used in) Financing Activities [Abstract] Non-PEO NEO Non-PEO NEO [Member] Adjustment to Compensation: Adjustment to Compensation [Axis] Construction in progress Construction in Progress Including Land, Gross Construction in Progress Including Land, Gross Debt Instrument [Line Items] Debt Instrument [Line Items] Weighted average shares of common stock outstanding-basic (in shares) Weighted average units outstanding - basic (in shares) Weighted Average Number of Shares Outstanding, Basic Leasing commissions Increase (Decrease) in Lease Acquisition Costs Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Cost of Real Estate Sold SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Accumulated Depreciation, Investment in Real Estate Sold Properties held for development Real Estate Properties Held For Development The number of real estate properties held for development. Proceeds from issuance of unsecured notes payable Proceeds from Unsecured Notes Payable REVENUE: Revenues [Abstract] Forfeiture of restricted stock (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Rental income Total rental income Operating Lease, Lease Income Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Statement [Line Items] Statement [Line Items] Deferred: Deferred Federal, State and Local, Tax Expense (Benefit) [Abstract] Forward-starting swap realized gain included in loss on early extinguishment of debt Forward Starting Swap, Early Extinguishment Of Debt [Member] Forward Starting Swap, Early Extinguishment Of Debt Partner Type [Axis] Partner Type [Axis] Summary of Notes Payable Outstanding Schedule of Debt [Table Text Block] Gain on derivatives Derivative, Gain on Derivative Name of Property [Axis] Name of Property [Axis] Noncontrolling Interests - Unitholders in the Operating Partnership Noncontrolling Interest [Member]