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ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP - Narrative (Details) | 9 Months Ended
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Sep. 30, 2025 a ft² property
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of real estate properties | property | 63
Area of real estate property (in square feet) | 11,755,704
Unconsolidated Properties | Unconsolidated Real Estate Ventures |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Number of real estate properties | property | 9
Parent Company |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property (in square feet) | 11,900,000
Areas of land held for development (in acres) | a | 129.5
Lease agreement term | 99 years
Area of additional undeveloped parcels of land with option to purchase (in acres) | a | 5.1
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
Wholly-owned Management Company Subsidiaries |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property (in square feet) | 18,900,000
Wholly-owned Management Company Subsidiaries | Wholly Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property (in square feet) | 11,800,000
Wholly-owned Management Company Subsidiaries | Partially Owned Properties |
Organization of The Parent Company and The Operating Partnership [Line Items] |
Area of real estate property (in square feet) | 7,100,000
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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