CONSOLIDATED STATEMENTS OF PARTNERS’ EQUITY - BRANDYWINE OPERATING PARTNERSHIP, L.P. - USD ($) $ in Thousands	Total	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest - Consolidated Real Estate Ventures	BRANDYWINE OPERATING PARTNERSHIP, L.P.	BRANDYWINE OPERATING PARTNERSHIP, L.P. Accumulated Other Comprehensive Income (Loss)	BRANDYWINE OPERATING PARTNERSHIP, L.P. Noncontrolling Interest - Consolidated Real Estate Ventures	BRANDYWINE OPERATING PARTNERSHIP, L.P. General Partner Capital
Beginning balance (in shares) at Dec. 31, 2022							171,569,807
Beginning balance at Dec. 31, 2022				$ 1,630,139	$ 3,569	$ 2,832	$ 1,623,738
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	$ (5,276)		$ (17)	(5,276)		(1)	$ (5,275)
Other comprehensive income (loss)	(5,291)	$ (5,307)	16	(5,291)	(5,291)
Deferred compensation obligation (in shares)							(13,422)
Deferred compensation obligation	(88)			(88)			$ (88)
Repurchase and retirement of LP units				0
Share-based compensation activity (in shares)							171,318
Share-based compensation activity	3,371			3,371			$ 3,371
Adjustment of redeemable partnership units to liquidation value at period end				779			779
Distributions declared to general partnership unit holders				(32,734)			$ (32,734)
Ending balance (in shares) at Mar. 31, 2023							171,727,703
Ending balance at Mar. 31, 2023				1,590,900	(1,722)	2,831	$ 1,589,791
Beginning balance (in shares) at Dec. 31, 2022							171,569,807
Beginning balance at Dec. 31, 2022				1,630,139	3,569	2,832	$ 1,623,738
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(39,649)			(39,649)
Other comprehensive income (loss)	4,240			4,240
Ending balance (in shares) at Sep. 30, 2023							172,097,661
Ending balance at Sep. 30, 2023				1,512,086	7,809	2,811	$ 1,501,466
Beginning balance (in shares) at Mar. 31, 2023							171,727,703
Beginning balance at Mar. 31, 2023				1,590,900	(1,722)	2,831	$ 1,589,791
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(12,737)		(41)	(12,737)			$ (12,737)
Other comprehensive income (loss)	6,646	6,626	20	6,646	6,646
Deferred compensation obligation	0
Share-based compensation activity (in shares)							374,226
Share-based compensation activity	2,616			2,616			$ 2,616
Adjustment of redeemable partnership units to liquidation value at period end				(98)			(98)
Distributions declared to general partnership unit holders				(32,985)			$ (32,985)
Ending balance (in shares) at Jun. 30, 2023							172,101,929
Ending balance at Jun. 30, 2023				1,554,342	4,924	2,831	$ 1,546,587
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(21,636)		(82)	(21,636)		(20)	$ (21,616)
Other comprehensive income (loss)	2,885	2,909	(24)	2,885	2,885
Deferred compensation obligation (in shares)							(4,268)
Deferred compensation obligation	(20)			(20)			$ (20)
Share-based compensation activity	2,506			2,506			2,506
Adjustment of redeemable partnership units to liquidation value at period end				(41)			(41)
Distributions declared to general partnership unit holders				(25,950)			$ (25,950)
Ending balance (in shares) at Sep. 30, 2023							172,097,661
Ending balance at Sep. 30, 2023				1,512,086	7,809	2,811	$ 1,501,466
Beginning balance (in shares) at Dec. 31, 2023							172,097,661
Beginning balance at Dec. 31, 2023				1,321,372	(1,010)	2,810	$ 1,319,572
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(16,414)		(46)	(16,414)		3	$ (16,417)
Other comprehensive income (loss)	6,026	6,007	19	6,026	6,026
Deferred compensation obligation (in shares)							(21,234)
Deferred compensation obligation	(100)			(100)			$ (100)
Share-based compensation activity (in shares)							194,480
Share-based compensation activity	4,831			4,831			$ 4,831
Adjustment of redeemable partnership units to liquidation value at period end				316			316
Distributions declared to general partnership unit holders				(26,177)			$ (26,177)
Ending balance (in shares) at Mar. 31, 2024							172,270,907
Ending balance at Mar. 31, 2024				1,289,854	5,016	2,813	$ 1,282,025
Beginning balance (in shares) at Dec. 31, 2023							172,097,661
Beginning balance at Dec. 31, 2023				1,321,372	(1,010)	2,810	$ 1,319,572
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(151,867)			(151,867)
Other comprehensive income (loss)	(3,112)			(3,112)
Ending balance (in shares) at Sep. 30, 2024							172,665,995
Ending balance at Sep. 30, 2024				1,101,957	(4,122)	2,813	$ 1,103,266
Beginning balance (in shares) at Mar. 31, 2024							172,270,907
Beginning balance at Mar. 31, 2024				1,289,854	5,016	2,813	$ 1,282,025
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	30,267		94	30,267		3	$ 30,264
Other comprehensive income (loss)	781	778	3	781	781
Deferred compensation obligation (in shares)							(43)
Deferred compensation obligation	0
Share-based compensation activity (in shares)							407,226
Share-based compensation activity	2,359			2,359			$ 2,359
Adjustment of redeemable partnership units to liquidation value at period end				16			16
Distributions declared to general partnership unit holders				(26,179)			$ (26,179)
Ending balance (in shares) at Jun. 30, 2024							172,678,090
Ending balance at Jun. 30, 2024				1,297,098	5,797	2,816	$ 1,288,485
Increase (Decrease) in Partners' Capital [Roll Forward]
Net (loss) income	(165,720)		(500)	(165,720)		(3)	$ (165,717)
Other comprehensive income (loss)	(9,919)	$ (9,890)	$ (29)	(9,919)	(9,919)
Deferred compensation obligation (in shares)							(12,095)
Deferred compensation obligation	(59)			(59)			$ (59)
Share-based compensation activity	$ 7,284			7,284			7,284
Adjustment of redeemable partnership units to liquidation value at period end				(551)			(551)
Distributions declared to general partnership unit holders				(26,176)			$ (26,176)
Ending balance (in shares) at Sep. 30, 2024							172,665,995
Ending balance at Sep. 30, 2024				$ 1,101,957	$ (4,122)	$ 2,813	$ 1,103,266