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SIGNIFICANT ACCOUNTING POLICIES (Business) (Details) | Dec. 31, 2020 ft² item property | Dec. 31, 2019 item | Dec. 31, 2018 item
--- | --- | --- | ---
Wholly owned properties |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 29 |  |
Wholly owned properties | Residential and mixed-use properties |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 25 |  |
Number of units | 2,892 |  |
Wholly owned properties | Residential buildings |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 21 |  |
Wholly owned properties | Mixed use residential, retail and office buildings |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 4 |  |
Wholly owned properties | Commercial |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 3 |  |
Area of property (in square feet) | ft² | 108,043 |  |
Wholly owned properties | Condominium |  |  |
Line of Business |  |  |
Number of Real Estate Properties | property | 1 |  |
Number of units | 19 |  |
Partially owned properties | Residential and mixed-use properties |  |  |
Line of Business |  |  |
Number of Real Estate Properties | 7 |  |
Number of properties after balance sheet date | 688 |  |
Number of units | 688 |  |
Partially owned properties | Residential and mixed-use properties | Minimum |  |  |
Line of Business |  |  |
Ownership interest (as a percent) | 40.00% |  |
Partially owned properties | Commercial |  |  |
Line of Business |  |  |
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) | 50 |  |
Investment Properties |  |  |
Line of Business |  |  |
Number of units | 865 | 913 | 913
Investment Properties | Minimum |  |  |
Line of Business |  |  |
Ownership interest (as a percent) | 40.00% |  |
Investment Properties | Maximum |  |  |
Line of Business |  |  |
Ownership interest (as a percent) | 50.00% |  |
Investment Properties | Residential buildings |  |  |
Line of Business |  |  |
Number of units | 862 | 910 | 910
Investment Properties | Commercial |  |  |
Line of Business |  |  |
Number of units | 3 | 3 | 3
Investment Properties | Partially owned properties | Residential and mixed-use properties |  |  |
Line of Business |  |  |
Number of Real Estate Properties | 7 |  |
Investment Properties | Partially owned properties | Residential and mixed-use properties | Minimum |  |  |
Line of Business |  |  |
Ownership interest (as a percent) | 40.00% |  |
Investment Properties | Partially owned properties | Residential and mixed-use properties | Maximum |  |  |
Line of Business |  |  |
Ownership interest (as a percent) | 50.00% |  |

X
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