DERIVATIVE AND HEDGING ACTIVITIES (Details) - Designated as Hedging Instrument - Cash Flow Hedging - American Assets Trust, L.P.	6 Months Ended
Jun. 30, 2018 USD ($)
Interest Rate Swap, 1/9/2019 \| Bank of America, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	$ 100,000,000
Effective Date	Jan. 09, 2014
Maturity Date	Jan. 09, 2019
Interest rate swap asset	$ 236,000
Interest Rate Swap, 3/1/2023 \| U.S. Bank N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	$ 100,000,000
Effective Date	Mar. 01, 2016
Maturity Date	Mar. 01, 2023
Interest rate swap asset	$ 5,693,000
Interest Rate Swap, 3/1/2023 \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount	$ 50,000,000
Effective Date	May 02, 2016
Maturity Date	Mar. 01, 2023
Interest rate swap asset	$ 2,889,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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