DERIVATIVE AND HEDGING ACTIVITIES (Details)	9 Months Ended
	Sep. 30, 2023 USD ($)
Fair Value
Estimated derivative reclassification from accumulated OCI to income	$ 400,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2027 | Bank of America, N.A.
Notional Amount
Interest rate swap asset	50,000,000
Fair Value
Interest rate swap asset	4,758,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2027 | Wells Fargo Bank, N.A.
Notional Amount
Interest rate swap asset	50,000,000
Fair Value
Interest rate swap asset	4,764,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2025 | Wells Fargo Bank, N.A.
Notional Amount
Interest rate swap asset	150,000,000
Fair Value
Interest rate swap asset	2,406,000
Designated as Hedging Instrument | Cash Flow Hedging | American Assets Trust, L.P. | Interest Rate Swap, 1/5/2025 | Mizuho Capital Markets LLC
Notional Amount
Interest rate swap liability	75,000,000
Fair Value
Interest rate swap liability	$ 720,000