PARTNERS' EQUITY OF THE PARENT COMPANY - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Numerator
Net income (loss)	$ (196,487)	$ (197,403)	$ 53,992
Nonforfeitable dividends allocated to unvested restricted shareholders, Basic	(1,178)	(567)	(456)
Nonforfeitable dividends allocated to unvested restricted shareholders, Diluted	(1,178)	(567)	(456)
Net income (loss) attributable to common shareholders, Basic	(197,085)	(197,356)	53,368
Net income (loss) attributable to common shareholders, Diluted	$ (197,085)	$ (197,356)	$ 53,368
Denominator
Weighted average units outstanding, basic (in shares)	172,526,996	171,959,210	171,491,369
Contingent securities/Share based compensation (in shares)	0	0	834,277
Weighted average shares outstanding, diluted (in shares)	172,526,996	171,959,210	172,325,646
Earnings (loss) per Common Partnership Unit:
Basic income (loss) per Common Share	$ (1.14)	$ (1.15)	$ 0.31
Net income (loss) attributable to common shareholders, Diluted (in dollars per share)	$ (1.14)	$ (1.15)	$ 0.31
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Numerator
Net income (loss)	$ (196,487)	$ (197,403)	$ 53,992
Net (income) loss attributable to noncontrolling interests	(5)	22	2
Nonforfeitable dividends allocated to unvested restricted shareholders, Basic	(1,178)	(567)	(456)
Nonforfeitable dividends allocated to unvested restricted shareholders, Diluted	(1,178)	(567)	(456)
Net income (loss) attributable to common shareholders, Basic	(197,670)	(197,948)	53,538
Net income (loss) attributable to common shareholders, Diluted	$ (197,670)	$ (197,948)	$ 53,538
Denominator
Weighted average units outstanding, basic (in shares)	173,042,591	172,475,645	172,036,481
Contingent securities/Share based compensation (in shares)	0	0	834,277
Weighted average shares outstanding, diluted (in shares)	173,042,591	172,475,645	172,870,758
Earnings (loss) per Common Partnership Unit:
Basic income (loss) per Common Share	$ (1.14)	$ (1.15)	$ 0.31
Net income (loss) attributable to common shareholders, Diluted (in dollars per share)	$ (1.14)	$ (1.15)	$ 0.31