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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2019	Mar. 01, 2019	Jul. 01, 2017
Related Party Transaction [Line Items]
Total rental income	$ 93,147	$ 78,079	$ 249,634	$ 231,172
Investment in WBW CHP LLC (as a percent)			47.70%
WBW CHP LLC
Related Party Transaction [Line Items]
Amount recovered for reimbursements of operating expense for related party			$ 900	800
ICW Inc \| Board of Directors Chairman
Related Party Transaction [Line Items]
Prepaid Insurance							$ 200
American Assets, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Lease term						3 years
Total rental income			200
EDisability, LLC \| Board of Directors Chairman
Related Party Transaction [Line Items]
Total rental income			100
AAI Aviation, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Aviation expense			$ 200	$ 0
Scenario, Forecast \| American Assets, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Total rental income					$ 200