v3.25.4

DERIVATIVE AND HEDGING ACTIVITIES - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Sep. 10, 2024	Dec. 31, 2025	Sep. 17, 2024	Sep. 09, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Reclassified within twelve months		$ 1.0
American Assets Trust, L.P. | 6.150% Senior Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Interest Rate			6.15%
American Assets Trust, L.P. | 6.150% Senior Notes | Unsecured term loan
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Interest Rate		6.15%	6.15%
Effective interest rate (percent)		6.209%	6.194%
American Assets Trust, L.P. | Interest Rate Swap | Term Loan A
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		2.70%
American Assets Trust, L.P. | Interest Rate Swap | Term Loan B | First period
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		5.47%
American Assets Trust, L.P. | Interest Rate Swap | Term Loan B | Second period
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		5.57%
American Assets Trust, L.P. | Interest Rate Swap | Term Loan C | First period
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		5.57%
American Assets Trust, L.P. | Interest Rate Swap | Term Loan C | Second period
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		5.47%
American Assets Trust, L.P. | Forward Contracts | Series D Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		3.87%
American Assets Trust, L.P. | Forward Contracts | Series E Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		4.18%
American Assets Trust, L.P. | Forward Contracts | Series F Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		3.85%
American Assets Trust, L.P. | Forward Contracts | Series G Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fixed interest rate on derivative		3.88%
American Assets Trust, L.P. | Treasury Locks
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount	$ 150.0			$ 150.0
Loss on derivatives	$ 1.3
American Assets Trust, L.P. | Treasury Locks | 6.150% Senior Notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Effective interest rate (percent)		6.209%

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