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SIGNIFICANT ACCOUNTING POLICIES - Business (Details) | Sep. 30, 2025 USD ($) ft² property item | Sep. 30, 2024
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Line of Business |  |
Real Estate Assets Held for Sale | $ | $ 3,003,310 |
Partnership properties |  |
Line of Business |  |
Number of properties | 34 |
Partnership properties | Residential and mixed-use properties |  |
Line of Business |  |
Number of properties | 28 |
Number of units | item | 3,339 |
Partnership properties | Apartments |  |
Line of Business |  |
Number of properties | 22 |
Partnership properties | Mixed use residential, retail and office buildings |  |
Line of Business |  |
Number of properties | 6 |
Partnership properties | Commercial |  |
Line of Business |  |
Number of properties | 6 |
Area of property (in square feet) | ft² | 159,000 |
Partnership properties | Condominium |  |
Line of Business |  |
Number of properties | 1 |
Number of units | item | 19 |
Investment properties | Residential and mixed-use properties |  |
Line of Business |  |
Number of units | item | 688 |
Area of property (in square feet) | ft² | 12,500 |
Investment properties | Car parking lot |  |
Line of Business |  |
Capacity of real estate property (in cars per lot) | item | 50 |
Limited Partnerships | Investment properties | Residential and mixed-use properties |  |
Line of Business |  |
Number of properties | 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%

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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 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 Reference 2: 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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- Definition Amount of investment in land and building held for sale. Excludes real estate considered inventory. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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