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

+ Details

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Period Type:	instant

- 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.

+ Details

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Period Type:	duration

- Definition

Fixed interest rate related to the interest rate derivative.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- 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.

+ Details

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Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events (Details) - USD ($)			12 Months Ended
Subsequent Events (Details) - USD ($)	Mar. 01, 2016	Jan. 29, 2016	Dec. 31, 2015	Aug. 19, 2014
Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging \| Subsequent Event
Subsequent Event [Line Items]
Notional amount		$ 100,000,000
Fixed interest rate on derivative		1.4485%
American Assets Trust, L.P. \| Subsequent Event \| Scenario, Forecast \| Term Loan
Subsequent Event [Line Items]
Number of year amortization schedule	7 years
American Assets Trust, L.P. \| Interest Rate Swap
Subsequent Event [Line Items]
Term of derivative contract			7 years
Notional amount				$ 150,000,000
Fixed interest rate on derivative			3.08%	2.1305%
American Assets Trust, L.P. \| Interest Rate Swap \| Subsequent Event
Subsequent Event [Line Items]
Term of derivative contract		7 years
American Assets Trust, L.P. \| Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging
Subsequent Event [Line Items]
Effective date			Jan. 09, 2014
Notional amount			$ 100,000,000
Maturity date			Jan. 09, 2019
Fixed interest rate on derivative			3.08%
American Assets Trust, L.P. \| Interest Rate Swap \| Designated as Hedging Instrument \| Cash Flow Hedging \| Subsequent Event
Subsequent Event [Line Items]
Effective date		Mar. 01, 2016
Maturity date		Mar. 01, 2023