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Organization of the Parent Company and The Operating Partnership (Tables) | 3 Months Ended
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Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract] |
Summary of Core Portfolio of Operating Properties and Excludes Development, Redevelopment and Held for Sale | 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 March 31, 2021:
| Number of Properties |  | Rentable Square Feet
Office properties | 71 |  |  | 12,006,744 |
Mixed-use properties | 5 |  |  | 942,334 |
Core Properties | 76 |  |  | 12,949,078 |
Development property | 1 |  |  | 204,000 |
Redevelopment properties | 4 |  |  | 498,318 |
The Properties | 81 |  |  | 13,651,396 |

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