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SIGNIFICANT ACCOUNTING POLICIES (Business) (Details) | Sep. 30, 2023 property | Sep. 30, 2023 item | Sep. 30, 2023 ft² | Sep. 30, 2023 | Aug. 23, 2023 | Jul. 14, 2023 ft² property | Sep. 30, 2022
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Residential and mixed-use properties |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties |  |  |  |  |  | 3 |
Commercial |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Area of property (in square feet) | ft² |  |  |  |  |  | 3,400 |
Wholly owned properties |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 31 |  |  |  |  |  |
Wholly owned properties | Residential and mixed-use properties |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 27 |  |  |  |  |  |
Number of units | item |  | 2,944 |  |  |  |  |
Wholly owned properties | Residential buildings |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 22 |  |  |  |  |  |
Wholly owned properties | Mixed use residential, retail and office buildings |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 5 |  |  |  |  |  |
Wholly owned properties | Commercial |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 4 |  |  |  |  |  |
Area of property (in square feet) | ft² |  |  | 137,153 |  |  |  |
Wholly owned properties | Condominium |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | 1 |  |  |  |  |  |
Number of units | item |  | 19 |  |  |  |  |
Partially owned properties | Residential and mixed-use properties |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of units | 688 | 688 |  |  |  |  |
Area of property (in square feet) | ft² |  |  | 12,500 |  |  |  |
Partially owned properties | Car parking lot |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Capacity of real estate property (in cars per lot) | item |  | 50 |  |  |  |  |
Limited Partnerships | Partially owned properties | Residential and mixed-use properties |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Number of properties | item |  | 7 |  |  |  |  |
NERA 40% |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  | 40.00% |  |  | 40.00%
NERA 50% |  |  |  |  |  |  |
Line of Business |  |  |  |  |  |  |
Ownership interest (as a percent) |  |  |  | 50.00% | 50.00% |  | 50.00%

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481687/323-10-50-3 + Details
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