v3.25.4

COMMITMENTS AND CONTINGENCIES (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2025 USD ($) mo property | Dec. 31, 2024
Commitment And Contingencies [Line Items] |  |
Termination payment, as high as | $ | $ 7,900 |
Revenues | Product Concentration Risk | Office Building |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 47.20% | 47.10%
Revenues | Product Concentration Risk | Retail Site |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 21.80% | 23.80%
Revenues | Customer Concentration Risk | Alamo Quarry Market and Waikele Center |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 9.30% | 8.80%
Base Rent | Customer Concentration Risk |  |
Commitment And Contingencies [Line Items] |  |
Annualized base rent reporting percentage | 2.00% |
Base Rent | Customer Concentration Risk | Google LLC at The Landmark at One Market |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 9.80% |
Base Rent | Customer Concentration Risk | LPL Holdings, Inc., Autodesk, Inc., and Smartsheet, Inc. |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 15.00% |
Southern California |  |
Commitment And Contingencies [Line Items] |  |
Number of consolidated properties located in Southern California | property | 16 |
Southern California | Revenues | Product Concentration Risk |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 43.80% | 43.20%
Hawaii | Revenues | Product Concentration Risk |  |
Commitment And Contingencies [Line Items] |  |
Percentage of total revenue provided by properties | 15.10% | 14.80%
Waikiki Beach Walk - Retail |  |
Commitment And Contingencies [Line Items] |  |
Property management fee, percent | 3.00% |
Outrigger Hotels |  |
Commitment And Contingencies [Line Items] |  |
Property management fee, percent | 6.00% |
Number of calendar months termination fee is based | 2 months |
Maximum percentage of hotel's fiscal year gross revenues paid for aggregate yearly management fee | 3.50% |
Previous months of management fees | 12 months |
Hotel management agreement default penalty factor of previous twelve months of management fees in first 11 years of term | 8 |
Years in hotel management agreement term | 11 years |
Hotel management agreement default penalty factor of previous twelve months of management fees in twelfth year of term | 4 |
Hotel management agreement default penalty factor of previous twelve months of management fees in thirteenth year of term | 3 |
Hotel management agreement default penalty factor of previous twelve months of management fees in fourteenth year of term | 2 |
Hotel management agreement default penalty factor of previous twelve months of management fees in fifteenth year of term | 1 |
Payment for management fee | $ | $ 12 |
Termination notice period | 30 days |
Outrigger Hotels | Year of Agreement, 12th |  |
Commitment And Contingencies [Line Items] |  |
Years in hotel management agreement term | 15 years |
Outrigger Hotels | Year of Agreement, 13th |  |
Commitment And Contingencies [Line Items] |  |
Years in hotel management agreement term | 14 years |
Outrigger Hotels | Year of Agreement, 14th |  |
Commitment And Contingencies [Line Items] |  |
Years in hotel management agreement term | 13 years |
Outrigger Hotels | Year of Agreement, 15th |  |
Commitment And Contingencies [Line Items] |  |
Years in hotel management agreement term | 12 years |
Outrigger Hotels | Maximum |  |
Commitment And Contingencies [Line Items] |  |
Property management fee, percent | 3.00% |
Wbw Hotel Lessee Llc |  |
Commitment And Contingencies [Line Items] |  |
Years of contract | 20 years |
Percentage of hotel occupancy gross revenue paid for program fee | 4.00% |
Wbw Hotel Lessee Llc | Future Time Period After 12-31-2021 |  |
Commitment And Contingencies [Line Items] |  |
Percentage of hotel occupancy gross revenue paid for franchise royalty fee | 5.00% |

X
- Definition Calendar months. + References No definition available. + Details
Name: | aat_CalendarMonths
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Commitment And Contingencies [Line Items] + References No definition available. + Details
Name: | aat_CommitmentAndContingenciesLineItems
Namespace Prefix: | aat_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Concentration Risk, Reporting Threshold Percentage + References No definition available. + Details
Name: | aat_ConcentrationRiskReportingThresholdPercentage
Namespace Prefix: | aat_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Hotel management agreement default penalty fact or of previous twelve months of Management fees in first eleven years of term. + References No definition available. + Details
Name: | aat_HotelManagementAgreementDefaultPenaltyFactOrOfPreviousTwelveMonthsOfManagementFeesInFirstElevenYearsOfTerm
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Hotel management agreement default penalty fact or of previous twelve months of Management fees in fourteenth year of term. + References No definition available. + Details
Name: | aat_HotelManagementAgreementDefaultPenaltyFactOrOfPreviousTwelveMonthsOfManagementFeesInFourteenthYearOfTerm
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Hotel management agreement default penalty fact or of previous twelve months of Management fees in thirteenth year of term. + References No definition available. + Details
Name: | aat_HotelManagementAgreementDefaultPenaltyFactOrOfPreviousTwelveMonthsOfManagementFeesInThirteenthYearOfTerm
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Hotel management agreement default penalty fact or of previous twelve months of Management fees in twelfth year of term. + References No definition available. + Details
Name: | aat_HotelManagementAgreementDefaultPenaltyFactOrOfPreviousTwelveMonthsOfManagementFeesInTwelfthYearOfTerm
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Hotel management agreement default penalty factor of previous twelve months of Management fees in fifteenth year of term. + References No definition available. + Details
Name: | aat_HotelManagementAgreementDefaultPenaltyFactorOfPreviousTwelveMonthsOfManagementFeesInFifteenthYearOfTerm
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum percentage of hotels fiscal year gross revenues paid for aggregate yearly Management fee. + References No definition available. + Details
Name: | aat_MaximumPercentageOfHotelsFiscalYearGrossRevenuesPaidForAggregateYearlyManagementFee
Namespace Prefix: | aat_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of consolidated properties. + References No definition available. + Details
Name: | aat_NumberOfConsolidatedProperties
Namespace Prefix: | aat_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of hotel occupancy gross revenue paid for franchise royalty fee. + References No definition available. + Details
Name: | aat_PercentageOfHotelOccupancyGrossRevenuePaidForFranchiseRoyaltyFee
Namespace Prefix: | aat_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of hotel occupancy gross revenue paid for program fee. + References No definition available. + Details
Name: | aat_PercentageOfHotelOccupancyGrossRevenuePaidForProgramFee
Namespace Prefix: | aat_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The previous months management fees used in the calculation of the management cancellation fee. + References No definition available. + Details
Name: | aat_PreviousMonthsOfManagementFees
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Property Management Fee, Monthly Fee + References No definition available. + Details
Name: | aat_PropertyManagementFeeMonthlyFee
Namespace Prefix: | aat_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Term period for termination of agreement. + References No definition available. + Details
Name: | aat_TermPeriodForTerminationOfAgreement
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Termination Notice Period + References No definition available. + Details
Name: | aat_TerminationNoticePeriod
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Years in hotel management agreement term. + References No definition available. + Details
Name: | aat_YearsInHotelManagementAgreementTerm
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Years of contract. + References No definition available. + Details
Name: | aat_YearsOfContract
Namespace Prefix: | aat_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-42 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-18 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 20 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-20 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-18 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-18 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-18 + Details
Name: | us-gaap_ConcentrationRiskPercentage1
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of the loss on termination of a contract for default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 912 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482291/912-20-45-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 912 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482269/912-20-50-1 + Details
Name: | us-gaap_LossOnContractTerminationForDefault
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The percentage charged for managing real estate properties. + References No definition available. + Details
Name: | us-gaap_PropertyManagementFeePercentFee
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_ProductConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_OfficeBuildingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_RetailSiteMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByTypeAxis=us-gaap_CustomerConcentrationRiskMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=aat_AlamoQuarryMarketandWaikeleCenterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConcentrationRiskByBenchmarkAxis=aat_TotalBaseRentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=aat_GoogleLLCAtTheLandmarkAtOneMarketMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_MajorCustomersAxis=aat_LPLHoldingsIncAutodeskIncAndSmartsheetIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=aat_SouthernCaliforniaMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=stpr_HI
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis=aat_WaikikiBeachWalkRetailMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis=aat_OutriggerHotelsAndResortsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aat_LineOfCreditFutureTimePeriodAxis=aat_FutureYearPeriodOneMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aat_LineOfCreditFutureTimePeriodAxis=aat_FutureYearPeriodTwoMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aat_LineOfCreditFutureTimePeriodAxis=aat_FutureYearPeriodThreeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aat_LineOfCreditFutureTimePeriodAxis=aat_FutureYearPeriodFourMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis=aat_WbwHotelLesseeLlcMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | aat_LineOfCreditFutureTimePeriodAxis=aat_FutureTimePeriodAfterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |