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

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

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

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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
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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Events (Details) - USD ($)	Jan. 18, 2017	Jan. 13, 2017	Sep. 19, 2014	Dec. 31, 2016	Apr. 07, 2016	Mar. 29, 2016	Mar. 23, 2016	Jan. 29, 2016	Aug. 19, 2014
Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Subsequent Event [Line Items]
Notional amount					$ 100,000,000	$ 150,000,000
American Assets Trust, L.P. \| Interest Rate Swap
Subsequent Event [Line Items]
Notional amount									$ 150,000,000
American Assets Trust, L.P. \| Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Subsequent Event [Line Items]
Notional amount				$ 100,000,000			$ 50,000,000	$ 100,000,000
Gain recognized in other comprehensive income (loss)			$ 1,600,000
American Assets Trust, L.P. \| Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging \| Subsequent Event
Subsequent Event [Line Items]
Gain recognized in other comprehensive income (loss)	$ 10,400,000
American Assets Trust, L.P. \| Forward Contracts
Subsequent Event [Line Items]
Effective interest rate (percent)				3.88%
Wells Fargo Bank, N.A. \| American Assets Trust, L.P. \| Interest Rate Swap, 3/31/2027 $150M \| Designated as Hedging Instrument \| Cash Flow Hedging
Subsequent Event [Line Items]
Notional amount				$ 150,000,000		$ 150,000,000
Wells Fargo Bank, N.A. \| American Assets Trust, L.P. \| Interest Rate Swap, 3/31/2027 $100M \| Designated as Hedging Instrument \| Cash Flow Hedging
Subsequent Event [Line Items]
Notional amount				$ 100,000,000	$ 100,000,000
Unsecured debt \| American Assets Trust, L.P. \| Subsequent Event \| Scenario, Forecast \| Senior Guaranteed Notes, Series D
Subsequent Event [Line Items]
Face amount of debt		$ 250,000,000
Stated Interest Rate		4.29%
Stated Maturity Date		Mar. 01, 2027
Debt issuance date		Mar. 01, 2017
Unsecured debt \| American Assets Trust, L.P. \| Forward Contracts \| Subsequent Event \| Scenario, Forecast \| Senior Guaranteed Notes, Series D
Subsequent Event [Line Items]
Effective interest rate (percent)		3.73%