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

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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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

No definition available.

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- Definition

The effective portion of gains on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

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- Definition

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

+ References

No definition available.

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- Definition

Period the derivative contract is outstanding, 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

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=49121117&loc=d3e13433-108611

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Derivative and Hedging (Details) - USD ($)			12 Months Ended
Derivative and Hedging (Details) - USD ($)	Sep. 19, 2014	Aug. 19, 2014	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative liabilities at fair value			$ 1,686,000	$ 1,448,000
American Assets Trust, L.P. \| Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount		$ 150,000,000
Fixed interest rate on derivative		2.1305%	3.08%
Term of derivative contract			7 years
American Assets Trust, L.P. \| Forward Contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Term of derivative contract		1 month	1 month
American Assets Trust, L.P. \| Cash Flow Hedging \| Designated as Hedging Instrument \| Interest Rate Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount			$ 100,000,000
Fixed interest rate on derivative			3.08%
Effective date			Jan. 09, 2014
Maturity date			Jan. 09, 2019
Derivative liabilities at fair value			$ 1,686,000
Gain recognized in other comprehensive income (loss)	$ 1,600,000