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Organization of The Parent Company and The Operating Partnership - Narrative (Details) | 3 Months Ended
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Mar. 31, 2021 a ft² parcel property
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of properties | property | 81
Net rentable area (in square feet) | 13,651,396
Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Areas of land held for development (in acres) | a | 228.5
Area of land held for sale (in acres) | a | 35.2
Area of additional undeveloped parcels of land with option to purchase (in acres) | a | 55.5
Total potential development capacity (in square feet) | 13,900,000
Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 24,500,000
Wholly Owned Properties | Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 13,700,000
Partially Owned Properties | Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 10,800,000
Land Parcel One | Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
Land Parcel Two | Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
Held-for-sale | Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Total potential development capacity (in square feet) | 200,000
Leashold Interest Land | Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Areas of land held for development (in acres) | a | 0.8
Number of parcels of land | parcel | 1
Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 99.40%
Unconsolidated Real Estate Ventures | Unconsolidated Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of properties | property | 10

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