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ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP - Narrative (Details) | 12 Months Ended
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Dec. 31, 2020 ft² a property managementCompany parcel
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of Properties | property | 82
Area of real estate property | 13,852,464
Number of management companies | managementCompany | 7
Wholly Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property | 13,900,000
Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of undeveloped parcels of land | a | 228.5
Area of undeveloped land held for sale | a | 35.2
Area of additional undeveloped parcels of land with option to purchase | a | 55.5
Total potential development capacity | 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 | Held for Sale Properties Included in Continuing Operations |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Total potential development capacity | 200,000
Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property | 24,700,000
Wholly-owned Management Company Subsidiaries | Wholly Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property | 13,900,000
Wholly-owned Management Company Subsidiaries | Partially Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property | 10,800,000
Leashold Interest Land |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
Leashold Interest Land | Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of Properties | parcel | 2
Undeveloped parcels of land held | a | 1.8
Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 99.40%
BRSCO | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BMH | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BPI | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BBL | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BPM | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BBS | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
BGCS | BRANDYWINE OPERATING PARTNERSHIP, L.P. | Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 100.00%
Unconsolidated Real Estate Ventures | Unconsolidated Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of Properties | property | 9

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