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ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP (Tables) | 12 Months Ended
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Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Summary of Core Portfolio of Operating Properties and Excludes Development and Redevelopment Properties Under Construction | The Company’s core portfolio of operating properties (the “Core Properties”) excludes development properties, redevelopment properties, and properties held for sale. The Properties were comprised of the following as of December 31, 2020:
| Number of Properties |  | Rentable Square Feet
Office properties | 73 |  |  | 12,470,257 |
Mixed-use properties | 5 |  |  | 942,334 |
Core Properties | 78 |  |  | 13,412,591 |
Development property | 1 |  |  | 205,803 |
Redevelopment properties | 3 |  |  | 234,070 |
The Properties | 82 |  |  | 13,852,464 |

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