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ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP - Narrative (Details) | 9 Months Ended
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Sep. 30, 2023 a ft² property parcel
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of real estate properties | property | 74
Rentable square feet | 13,179,875
Unconsolidated Properties | Unconsolidated Real Estate Ventures |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of real estate properties | property | 12
Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Rentable square feet | 12,700,000
Areas of land held for development (in acres) | a | 152.1
Lease agreement term | 99 years
Area of additional undeveloped parcels of land with option to purchase (in acres) | a | 55.1
Parent Company | Parcel of land |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Lease agreement term | 99 years
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 | 0.8
Number of parcels of land | parcel | 1
Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Rentable square feet | 22,700,000
Wholly-owned Management Company Subsidiaries | Wholly Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Rentable square feet | 13,200,000
Wholly-owned Management Company Subsidiaries | Partially Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Rentable square feet | 9,500,000
Brandywine Operating Partnership LP |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Ownership in the operating partnership | 99.70%

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