DERIVATIVE AND HEDGING ACTIVITIES (Details)	3 Months Ended
	Mar. 31, 2022 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Estimated derivative reclassification from Accumulated OCI to Income	$ 1,100,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 3/1/2023 | U.S. Bank N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	100,000,000
Fair Value	125,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 3/1/2023 | Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	50,000,000
Fair Value	55,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2027 | Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	50,000,000
Fair Value	1,802,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2027 | Bank of America, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	50,000,000
Fair Value	$ 1,807,000