DEBT - Summary of Total Secured Notes Payable Outstanding (Details) - American Assets Trust, L.P. - Secured notes payable, net - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, principal balance	$ 75,000	$ 111,000
Debt issuance costs, net	(445)	(35)
Total Debt Outstanding	74,555	110,965
Debt issuance costs, accumulated amortization	429	387
3.98% City Center Bellevue, November 2022
Debt Instrument [Line Items]
Long-term debt, principal balance	$ 0	111,000
Stated interest rate	3.98%
5.08% City Center Bellevue, October 2027
Debt Instrument [Line Items]
Long-term debt, principal balance	$ 75,000	$ 0
Stated interest rate	5.08%

Amount of accumulated amortization of debt issuance costs.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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