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

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

+ 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=73719730&loc=d3e13433-108611

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DERIVATIVE AND HEDGING ACTIVITIES (Details) - USD ($)								9 Months Ended
DERIVATIVE AND HEDGING ACTIVITIES (Details) - USD ($)	Mar. 31, 2017	May 02, 2016	Apr. 07, 2016	Mar. 29, 2016	Mar. 23, 2016	Mar. 01, 2016	Jan. 29, 2016	Sep. 30, 2016
American Assets Trust, L.P. \| Term Loan B
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Maturity Date						Mar. 01, 2023	Mar. 01, 2023
Face amount of debt						$ 100,000,000
Term of debt instrument						7 years
American Assets Trust, L.P. \| Term Loan B \| Unsecured term loans, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Maturity Date								Mar. 01, 2023
Face amount of debt						$ 100,000,000
American Assets Trust, L.P. \| Term Loan C
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Maturity Date		Mar. 01, 2023
Face amount of debt		$ 50,000,000
Term of debt instrument		7 years
American Assets Trust, L.P. \| Term Loan C \| Unsecured term loans, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated Maturity Date								Mar. 01, 2023
Face amount of debt		$ 50,000,000
American Assets Trust, L.P. \| Unsecured term loans, net \| Scenario, Forecast
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Term of debt instrument	10 years
American Assets Trust, L.P. \| Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative contract term			10 years	10 years
American Assets Trust, L.P. \| Interest Rate Swap \| Term Loan B
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative fixed interest rate (in percent)								3.15%
American Assets Trust, L.P. \| Interest Rate Swap \| Term Loan C
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative fixed interest rate (in percent)								3.14%
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount			$ 100,000,000	$ 150,000,000
Derivative fixed interest rate (in percent)			1.748%	1.88%
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap, 1/9/2019 \| Bank of America, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maturity Date								Jan. 09, 2019
Effective Date								Jan. 09, 2014
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap, 3/1/2023 \| U.S. Bank N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maturity Date								Mar. 01, 2023
Effective Date								Mar. 01, 2016
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap, 3/1/2023 \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maturity Date								Mar. 01, 2023
Effective Date								May 02, 2016
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap, 3/31/2027 $150M \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maturity Date								Mar. 31, 2027
Effective Date								Mar. 31, 2017
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap, 3/31/2027 \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maturity Date								Mar. 31, 2027
Effective Date								Mar. 31, 2017
Designated as Hedging Instrument \| Cash Flow Hedging \| American Assets Trust, L.P. \| Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative contract term					7 years		7 years
Notional Amount					$ 50,000,000		$ 100,000,000
Maturity Date			Mar. 31, 2027	Mar. 31, 2027	Mar. 01, 2023		Mar. 01, 2023
Derivative fixed interest rate (in percent)					1.441%		1.4485%
Effective Date			Mar. 31, 2017	Mar. 31, 2017	May 02, 2016		Mar. 01, 2016
Designated as Hedging Instrument \| Cash Flow Hedging \| American Assets Trust, L.P. \| Interest Rate Swap, 1/9/2019 \| Bank of America, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount								$ 100,000,000
Fair Value Liability								2,261,000
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 Liability								2,359,000
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 Liability								1,162,000
Designated as Hedging Instrument \| Cash Flow Hedging \| American Assets Trust, L.P. \| Interest Rate Swap, 3/31/2027 $150M \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount								150,000,000
Fair Value Liability								5,159,000
Designated as Hedging Instrument \| Cash Flow Hedging \| American Assets Trust, L.P. \| Interest Rate Swap, 3/31/2027 \| Wells Fargo Bank, N.A.
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional Amount								100,000,000
Fair Value Liability								$ 2,188,000