Percentage of investment in related party.

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- Definition

Other operating costs incurred during the reporting period and may include amounts paid to maintain the property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

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- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Section 50
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

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- Definition

Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands				12 Months Ended
	Jun. 01, 2021	Mar. 01, 2021	Mar. 01, 2019	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Transaction [Line Items]
Rental income				$ 419,373	$ 402,507	$ 360,208
General and administrative				35,960	32,143	29,879
Rental expenses				118,801	107,645	86,980
Related Party \| American Assets, Inc.
Related Party Transaction [Line Items]
Term of lease		10 years	3 years
Rental income		$ 200	$ 200	300	300	300
Related Party \| EDisability, LLC
Related Party Transaction [Line Items]
Term of lease	3 years
Rental income	$ 100			100	100	100
Related Party \| AAI Aviation, Inc.
Related Party Transaction [Line Items]
General and administrative				$ 200	200	200
Related Party \| WBW CHP LLC
Related Party Transaction [Line Items]
Investment in WBW CHP LLC, in percentage				47.70%
Rental expenses				$ 1,100	$ 1,300	$ 1,000
Related Party \| American Assets Trust, Inc. \| Mr. Rady And Affiliates
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling				35.80%
Related Party \| American Assets Trust, Inc. \| Mr. Rady And Affiliates \| Common Shares
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling				16.60%
Related Party \| American Assets Trust, Inc. \| Mr. Rady And Affiliates \| Member Units
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling				19.40%