Consolidated Statements of Partners' Equity - USD ($) $ in Thousands	Total	BRANDYWINE OPERATING PARTNERSHIP, L.P.	General Partner Capital [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.	Series E-linked Preferred Stock [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.	Accumulated Other Comprehensive Loss [Member]	Accumulated Other Comprehensive Loss [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.	Noncontrolling Interest [Member]	Noncontrolling Interest [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.
Beginning Balance at Dec. 31, 2015		$ 1,929,977	$ 1,836,692	$ 96,850		$ (5,597)		$ 2,032
Beginning Balance, Shares at Dec. 31, 2015			174,688,568	4,000,000
Net income	$ 44,987	44,987	$ 44,981				$ 367	6
Other comprehensive income (loss)	(12,686)	(12,686)			$ (12,577)	(12,686)	(109)
Share Issuance from/(to) Deferred Compensation Plan	(46)	(46)	$ (46)
Share Issuance from/(to) Deferred Compensation Plan, Shares			(8,252)
Issuance of partnership interest in consolidated real estate venture	54	54					54	54
Conversion of LP Units to Common Shares		875	$ 875				(875)
Conversion of LP Units to Common Shares, Shares			55,303
Share-based compensation activity	3,615	3,615	$ 3,615
Share-based compensation activity, Shares			365,414
Adjustment of redeemable partnership units to liquidation value at period end		(2,450)	$ (2,450)
Redemption value of limited partnership units		(875)	(875)
Distribution to preferred shareholders	(3,450)	(3,450)	(3,450)
Preferred Mirror Units redemption charge	0	0
Distributions to general partnership unitholders		(54,272)	(54,272)
Ending Balance at Jun. 30, 2016		1,905,729	$ 1,825,070	$ 96,850		(18,283)		2,092
Ending Balance, Shares at Jun. 30, 2016			175,101,033	4,000,000
Beginning Balance at Dec. 31, 2016		1,859,642	$ 1,762,764	$ 96,850		(2,122)		2,150
Beginning Balance, Shares at Dec. 31, 2016			175,140,760	4,000,000
Net income	28,969	28,969	$ 28,956				214	13
Other comprehensive income (loss)	220	220			$ 217	220	3
Redemption of Preferred Mirror Units		(96,850)		$ (96,850)
Redemption of Preferred Mirror Units, Shares				(4,000,000)
Share Issuance from/(to) Deferred Compensation Plan	(48)	(48)	$ (48)
Share Issuance from/(to) Deferred Compensation Plan, Shares			(1,718)
Issuance of LP Units		(491)	$ (491)
Issuance of partnership interest in consolidated real estate venture	33	33					$ 33	33
Share Choice Plan Issuance, Shares			(1,423)
Bonus share issuance	110	110	$ 110
Bonus share issuance, Shares			6,752
Share-based compensation activity	4,344	4,344	$ 4,344
Share-based compensation activity, Shares			245,444
Adjustment of redeemable partnership units to liquidation value at period end		(2,605)	$ (2,605)
Distribution to preferred shareholders	(2,032)	(2,032)	(2,032)
Preferred Mirror Units redemption charge	$ (3,181)	(3,181)	(3,181)
Distributions to general partnership unitholders		(56,314)	(56,314)
Ending Balance at Jun. 30, 2017		$ 1,731,797	$ 1,731,503			$ (1,902)		$ 2,196
Ending Balance, Shares at Jun. 30, 2017			175,389,815