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SALES OF PROPERTIES, PROPERTY HELD-FOR-SALE AND IMPAIRMENT LOSS - Property Held-for-Sale and Impairment loss (Details) - USD ($) | 3 Months Ended | 6 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2026 | Jun. 30, 2026 | Jun. 30, 2025 | Jun. 30, 2026 | Jun. 30, 2025 | Sep. 30, 2026 | Jun. 26, 2026 | May 12, 2026
SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE |  |  |  |  |  |  |  |
Gain (loss) on sale of real estate, net |  | $ 13,433,000 | $ 6,531,000 | $ 17,309,000 | $ 7,641,000 |  |  |
Impairment loss |  | 142,000 |  | 142,000 |  |  |  |
Retail property in Monroeville, Pennsylvania | Forecast |  |  |  |  |  |  |  |
SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE |  |  |  |  |  |  |  |
Gain (loss) on sale of real estate, net | $ 887,000 |  |  |  |  | $ 887,000 |  |
Retail property in Chicago, Illinois |  |  |  |  |  |  |  |
SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE |  |  |  |  |  |  |  |
Contracted sale price of property |  |  |  |  |  |  | $ 5,700,000 |
Impairment loss |  | 142,000 |  | 142,000 |  |  |  |
Retail property in Chicago, Illinois | Forecast |  |  |  |  |  |  |  |
SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE |  |  |  |  |  |  |  |
Gain (loss) on sale of real estate, net | $ (280,000) |  |  |  |  | $ (280,000) |  |
Properties held-for-sale | Retail property in Monroeville, Pennsylvania |  |  |  |  |  |  |  |
SALES OF PROPERTIES AND PROPERTY HELD-FOR-SALE |  |  |  |  |  |  |  |
Contracted sale price of property |  |  |  |  |  |  |  | $ 2,050,000
Net book value |  | $ 1,054,000 |  | $ 1,054,000 |  |  |  |

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