Additional term of revolving credit facility based on specified requirements.

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- Definition

Debt Instrument, Extension Options

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No definition available.

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- Definition

Debt Instrument, Extension Term

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- Definition

Debt Instrument, Partial Repayment, Minimum Percentage of Principal

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- Definition

Debt Instrument, Prepayment, Percentage of Principal Plus a Stated Amount

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- Definition

Debt Instrument, Variable Rate Basis, One

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- Definition

Debt Instrument, Variable Rate Basis, Three

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- Definition

Debt Instrument, Variable Rate Basis, Two

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- Definition

Line of credit facility material acquisition.

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No definition available.

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- Definition

Maximum leverage percentage of revolving credit facility.

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No definition available.

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- Definition

Line of Credit Facility, Allowable Additional Borrowing Capacity

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No definition available.

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- Definition

Maximum maturities of securities.

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No definition available.

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- Definition

Maximum Recourse Indebtedness of Total Asset Value

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No definition available.

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- Definition

Maximum Secured Leverage Ratio On Revolving Credit Facility

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No definition available.

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- Definition

Maximum Unsecured Leverage Ratio

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No definition available.

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- Definition

Minimum Fixed Charge Coverage Ratio On Revolving Credit Facility

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No definition available.

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- Definition

Minimum Tangible Net Worth

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No definition available.

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- Definition

Minimum Unsecured Interest Coverage Ratio

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No definition available.

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- Definition

Percent of secured indebtedness of the company's secured total assets value.

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No definition available.

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- Definition

Percentage limit on annual distributions in relation to funds from operations.

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No definition available.

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- Definition

Percentage of net proceeds of additional equity Issuances covenant of credit facility.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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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
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- Definition

The average effective interest rate during the reporting period.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Debt (Details)						12 Months Ended
Debt (Details)	Oct. 31, 2014 USD ($)	Jan. 09, 2014 USD ($) Extension_Option	Sep. 07, 2012	Jan. 10, 2012	Mar. 07, 2011	Dec. 31, 2015 USD ($) Extension_Option	Dec. 31, 2014 USD ($)	Jan. 19, 2011 USD ($)
Debt Instrument [Line Items]
Unsecured line of credit						$ 30,000,000	$ 0
Unsecured notes payable						450,000,000	250,000,000
Unsecured line of credit
Debt Instrument [Line Items]
Maximum leverage ratio of revolving credit facility		60.00%
Maximum secured leverage ratio on revolving credit facility		40.00%
Minimum fixed charge coverage ratio covenant threshold		1.5
Minimum interest coverage ratio covenant threshold		175.00%
Maximum unsecured leverage ratio (in percents)		60.00%
Minimum tangible net worth		$ 721,160,000.00
Percent of net proceeds of any additional equity issuances in relation to net proceeds as of Offering		75.00%
Maximum recourse indebtedness of total asset value (in percents)		15.00%
Percentage annual distributions cannot exceed funds from operations		95.00%
Unsecured line of credit \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		0.50%
Unsecured line of credit \| Eurodollar [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		1.00%
American Assets Trust, L.P.
Debt Instrument [Line Items]
Revolving credit facility borrowing limit, maximum borrowing capacity								$ 250,000,000.0
Years, maximum maturities of securities					30 years
Year, extension on term of revolving credit facility				1 year
Percent of secured indebtedness of the company's secured total asset value			55.00%
Line of credit facility material acquisition			100
Unsecured line of credit						30,000,000	0
Unsecured notes payable						450,000,000	250,000,000
American Assets Trust, L.P. \| Subject to meeting specified requirements and obtaining additional commitments
Debt Instrument [Line Items]
Revolving credit facility borrowing limit, maximum borrowing capacity								$ 400,000,000.0
American Assets Trust, L.P. \| Unsecured line of credit \| Base Rate [Member]
Debt Instrument [Line Items]
Variable rate basis		base rate
American Assets Trust, L.P. \| Unsecured line of credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Number of extensions available \| Extension_Option		2
Extension term (in months)		6 months
American Assets Trust, L.P. \| Note Purchase Agreement \| Senior Guaranteed Notes
Debt Instrument [Line Items]
Principal of non-recourse mortgage loan	$ 350,000,000
Partial debt repayment, minimum percentage of principal (in percent)	5.00%
Full debt repayment percentage of principal plus a Make-Whole Amount (in percent)	100.00%
American Assets Trust, L.P. \| Note Purchase Agreement \| Senior Guaranteed Notes, Series A
Debt Instrument [Line Items]
Principal of non-recourse mortgage loan	$ 150,000,000
Stated Interest Rate	4.04%
American Assets Trust, L.P. \| Note Purchase Agreement \| Senior Guaranteed Notes, Series B
Debt Instrument [Line Items]
Principal of non-recourse mortgage loan	$ 100,000,000
Stated Interest Rate	4.45%
American Assets Trust, L.P. \| Note Purchase Agreement \| Senior Guaranteed Notes, Series C
Debt Instrument [Line Items]
Principal of non-recourse mortgage loan	$ 100,000,000
Stated Interest Rate	4.50%
American Assets Trust, L.P. \| Amended and Restated Credit Facility
Debt Instrument [Line Items]
Revolving credit facility borrowing limit, maximum borrowing capacity		$ 350,000,000
Allowable additional borrowing capacity		$ 250,000,000
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Minimum \| Revolving Credit Facility \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		0.35%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Maximum \| Revolving Credit Facility \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		0.95%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit
Debt Instrument [Line Items]
Unsecured line of credit						$ 30,000,000
Weighted average interest rate (in percent)						1.54%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit \| Base Rate [Member]
Debt Instrument [Line Items]
Prime rate		prime rate
Federal funds rate		federal funds rate
Eurodollar		Eurodollar
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility borrowing limit, maximum borrowing capacity		$ 250,000,000
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Variable rate basis		LIBOR
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit \| Minimum \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		1.35%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured line of credit \| Maximum \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		1.95%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured term loan
Debt Instrument [Line Items]
Revolving credit facility borrowing limit, maximum borrowing capacity		$ 100,000,000
Number of extensions available \| Extension_Option		3
Extension term (in months)		12 months
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured term loan \| Minimum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		1.30%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured term loan \| Minimum \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		0.30%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured term loan \| Maximum \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		1.90%
American Assets Trust, L.P. \| Amended and Restated Credit Facility \| Unsecured term loan \| Maximum \| Base Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (in percents)		0.90%
American Assets Trust, L.P. \| Term Loan
Debt Instrument [Line Items]
Number of extensions available \| Extension_Option						2
Extension term (in months)						12 months
Unsecured notes payable		$ 100,000,000				$ 100,000,000	$ 100,000,000