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PARTNERS' CAPITAL OF AMERICAN ASSETS TRUST, L.P. (Details) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 shares | Sep. 30, 2024 shares | Sep. 30, 2025 shares | Sep. 30, 2024 shares
American Assets Trust, L.P. |  |  |  |
Capital Unit [Line Items] |  |  |  |
Percentage of ownership interests classified as noncontrolling | 21.10% |  | 21.10% |
American Assets Trust, L.P. |  |  |  |
Capital Unit [Line Items] |  |  |  |
Noncontrolling common units (in shares) | 16,181,537 |  | 16,181,537 |
American Assets Trust, L.P. | Operating Partnership Units |  |  |  |
Capital Unit [Line Items] |  |  |  |
Antidilutive securities excluded from computation of EPS (in shares) | 606,062 | 581,314 | 602,093 | 583,247
American Assets Trust, L.P. | Common Shares |  |  |  |
Capital Unit [Line Items] |  |  |  |
Conversion of operating partnership units (in shares) |  |  | 0 |
American Assets Trust, L.P. | Limited Partners |  |  |  |
Capital Unit [Line Items] |  |  |  |
Common unit conversion ratio |  |  | 1 |

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