Partners Equity of the Operating Partnership (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Numerator
Income (Loss) from Continuing Operations, Basic	$ (2,237)	$ (2,245)
Income (Loss) From Continuing Operations, Diluted	(2,237)	(2,245)
Amount allocated to unvested restricted shareholders/unitholders, Basic	(103)	(108)
Amount allocated to unvested restricted shareholders/unitholders, Diluted	(103)	(108)
Preferred share/unit dividends, Basic	(1,725)	(1,725)
Preferred share/unit dividends, Diluted	(1,725)	(1,725)
Net income attributable to non-controlling interest — partners' share of consolidated real estate ventures	(12)	0
Noncontrolling Interest in Net Income (Loss) Joint Venture Partners, Redeemable, Diluted	12	0
Income (Loss) from Discontinued Operations	(8)	6,164
Net income (loss) attributable to Common Shareholders of Brandywine Realty Trust	(4,041)	2,058
Net Income (Loss) Available to Common Shareholders/unitholders, Diluted	(4,041)	2,058
Denominator
Weighted-average units outstanding, Basic	156,794,019	143,605,659
Weighted Average Number of Shares Outstanding, Diluted	156,794,019	143,605,659
Earnings per Common Partnership Unit [Abstract]
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Basic Share	$ (0.03)	$ (0.03)
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Diluted Share	$ (0.03)	$ (0.03)
Discontinued Operations attributable to common shareholders/unitholders, Basic	$ 0.00	$ 0.04
Discontinued Operations attributable to common shareholders/unitholders, Diluted	$ 0.00	$ 0.04
Net income (loss) attributable to common shareholders/unitholders, Basic	$ (0.03)	$ 0.01
Net income attributable to common shareholders/unitholders, Diluted	$ (0.03)	$ 0.01
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Numerator
Income (Loss) from Continuing Operations, Basic	(2,237)	(2,245)
Income (Loss) From Continuing Operations, Diluted	(2,237)	(2,245)
Amount allocated to unvested restricted shareholders/unitholders, Basic	(103)	(108)
Amount allocated to unvested restricted shareholders/unitholders, Diluted	(103)	(108)
Preferred share/unit dividends, Basic	(1,725)	(1,725)
Preferred share/unit dividends, Diluted	(1,725)	(1,725)
Net income attributable to non-controlling interest — partners' share of consolidated real estate ventures	(12)	0
Noncontrolling Interest in Net Income (Loss) Joint Venture Partners, Redeemable, Diluted	12	0
Income (Loss) from continuing operations available to common unitholders, Basic	(4,077)	(4,078)
Income (Loss) from continuing operations available to common unitholders, Diluted	(4,077)	(4,078)
Income (Loss) from Discontinued Operations	(8)	6,164
Income (Loss) From Discontinued Operations, Diluted	(8)	6,164
Net income (loss) attributable to Common Shareholders of Brandywine Realty Trust	(4,085)	2,086
Net Income (Loss) Available to Common Shareholders/unitholders, Diluted	$ (4,085)	$ 2,086
Denominator
Weighted-average units outstanding, Basic	158,557,758	145,451,396
Weighted Average Number of Shares Outstanding, Diluted	158,557,758	145,451,396
Earnings per Common Partnership Unit [Abstract]
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Basic Share	$ (0.03)	$ (0.03)
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Diluted Share	$ (0.03)	$ (0.03)
Discontinued Operations attributable to common shareholders/unitholders, Basic	$ 0.00	$ 0.04
Discontinued Operations attributable to common shareholders/unitholders, Diluted	$ 0.00	$ 0.04
Net income (loss) attributable to common shareholders/unitholders, Basic	$ (0.03)	$ 0.01
Net income attributable to common shareholders/unitholders, Diluted	$ (0.03)	$ 0.01