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Organization of The Parent Company and The Operating Partnership - Summary of Core Portfolio of Operating Properties and Excludes Development, Redevelopment and Held for Sale (Details) | Sep. 30, 2019 ft² property
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Real Estate Properties [Line Items] |
Number of properties | property | 95
Net rentable area (in square feet) | ft² | 16,711,387
Office properties |
Real Estate Properties [Line Items] |
Number of properties | property | 87
Net rentable area (in square feet) | ft² | 15,509,004
Mixed-use properties |
Real Estate Properties [Line Items] |
Number of properties | property | 3
Net rentable area (in square feet) | ft² | 641,741
Retail property |
Real Estate Properties [Line Items] |
Number of properties | property | 1
Net rentable area (in square feet) | ft² | 17,884
Core Properties |
Real Estate Properties [Line Items] |
Number of properties | property | 91
Net rentable area (in square feet) | ft² | 16,168,629
Development property |
Real Estate Properties [Line Items] |
Number of properties | property | 1
Net rentable area (in square feet) | ft² | 204,108
Redevelopment properties |
Real Estate Properties [Line Items] |
Number of properties | property | 3
Net rentable area (in square feet) | ft² | 338,650

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- Definition Area of a real estate property. + References No definition available. + Details
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