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Organization of The Parent Company and The Operating Partnership (Textual) (Details) | 9 Months Ended
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Sep. 30, 2019 a ft² parcel property
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of properties | property | 95
Net rentable area (in square feet) | 16,711,387
Unconsolidated Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of properties | property | 10
Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Areas of land held for development (in acres) | a | 234.7
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) | 14,200,000
Parent Company | Land Parcel One |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
Parent Company | Land Parcel Two |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
Parent Company | Assets Held-for-sale |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Total potential development capacity (in square feet) | 200,000
Parent Company | Leashold Interest Land |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Areas of land held for development (in acres) | a | 1.8
Number of parcels of land | parcel | 2
Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 24,600,000
Wholly-owned Management Company Subsidiaries | Wholly Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 16,700,000
Wholly-owned Management Company Subsidiaries | Partially Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Net rentable area (in square feet) | 7,900,000
Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 99.40%

X
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- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
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