Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue
Revenue	$ 120,418	$ 126,106	$ 361,289	$ 408,031
Operating expenses
Property operating expenses	30,304	31,567	88,503	102,320
Real estate taxes	13,421	14,923	42,784	48,525
Third party management expenses	3,327	2,509	9,866	7,546
Depreciation and amortization	48,175	43,533	131,303	145,314
General and administrative expenses	7,076	7,069	22,016	23,973
Total operating expenses	102,303	99,601	294,472	327,678
Gain on sale of real estate
Net gain on disposition of real estate	0	271,901	142	274,487
Net gain on sale of undepreciated real estate	910	0	2,903	201
Total gain on sale of real estate	910	271,901	3,045	274,688
Operating income	19,025	298,406	69,862	355,041
Other income (expense):
Interest and investment income	4,494	467	7,845	1,487
Interest expense	(15,190)	(16,310)	(46,973)	(56,510)
Interest expense - amortization of deferred financing costs	(709)	(715)	(2,127)	(2,195)
Equity in loss of unconsolidated real estate ventures	(6,634)	(5,788)	(20,798)	(9,882)
Net gain on real estate venture transactions	0	75	0	75
Net income before income taxes	986	276,135	7,809	288,016
Income tax (provision) benefit	(12)	(2)	(46)	224
Net income	974	276,133	7,763	288,240
Net income attributable to noncontrolling interests	(7)	(1,612)	(42)	(1,701)
Net income attributable to Brandywine Realty Trust	967	274,521	7,721	286,539
Nonforfeitable dividends allocated to unvested restricted shareholders	(91)	(93)	(331)	(317)
Net income attributable to Common Shareholders of Brandywine Realty Trust	$ 876	$ 274,428	$ 7,390	$ 286,222
Basic income per Common Share (in dollars per share)	$ 0.01	$ 1.61	$ 0.04	$ 1.66
Diluted income per Common Share (in dollars per share)	$ 0.01	$ 1.60	$ 0.04	$ 1.66
Basic weighted average shares outstanding (in shares)	170,907,018	170,573,028	170,794,585	172,380,410
Diluted weighted average shares outstanding (in shares)	172,237,194	171,026,492	172,077,950	172,735,436
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Revenue
Revenue	$ 120,418	$ 126,106	$ 361,289	$ 408,031
Operating expenses
Property operating expenses	30,304	31,567	88,503	102,320
Real estate taxes	13,421	14,923	42,784	48,525
Third party management expenses	3,327	2,509	9,866	7,546
Depreciation and amortization	48,175	43,533	131,303	145,314
General and administrative expenses	7,076	7,069	22,016	23,973
Total operating expenses	102,303	99,601	294,472	327,678
Gain on sale of real estate
Net gain on disposition of real estate	0	271,901	142	274,487
Net gain on sale of undepreciated real estate	910	0	2,903	201
Total gain on sale of real estate	910	271,901	3,045	274,688
Operating income	19,025	298,406	69,862	355,041
Other income (expense):
Interest and investment income	4,494	467	7,845	1,487
Interest expense	(15,190)	(16,310)	(46,973)	(56,510)
Interest expense - amortization of deferred financing costs	(709)	(715)	(2,127)	(2,195)
Equity in loss of unconsolidated real estate ventures	(6,634)	(5,788)	(20,798)	(9,882)
Net gain on real estate venture transactions	0	75	0	75
Net income before income taxes	986	276,135	7,809	288,016
Income tax (provision) benefit	(12)	(2)	(46)	224
Net income	974	276,133	7,763	288,240
Net (income) loss attributable to noncontrolling interests - consolidated real estate ventures	2	2	4	(20)
Net income attributable to Brandywine Operating Partnership	976	276,135	7,767	288,220
Nonforfeitable dividends allocated to unvested restricted shareholders	(91)	(93)	(331)	(317)
Net income attributable to Common Shareholders of Brandywine Realty Trust	$ 885	$ 276,042	$ 7,436	$ 287,903
Basic income per Common Share (in dollars per share)	$ 0.01	$ 1.61	$ 0.04	$ 1.66
Diluted income per Common Share (in dollars per share)	$ 0.01	$ 1.60	$ 0.04	$ 1.66
Basic weighted average shares outstanding (in shares)	171,731,001	171,554,662	171,710,387	173,362,044
Diluted weighted average shares outstanding (in shares)	173,061,177	172,008,126	172,993,752	173,717,070
Rents
Revenue
Revenue	$ 112,159	$ 121,277	$ 336,878	$ 392,661
Rents | BRANDYWINE OPERATING PARTNERSHIP, L.P.
Revenue
Revenue	112,159	121,277	336,878	392,661
Third party management fees, labor reimbursement and leasing
Revenue
Revenue	6,500	4,324	19,778	13,339
Third party management fees, labor reimbursement and leasing | BRANDYWINE OPERATING PARTNERSHIP, L.P.
Revenue
Revenue	6,500	4,324	19,778	13,339
Other
Revenue
Revenue	1,759	505	4,633	2,031
Other | BRANDYWINE OPERATING PARTNERSHIP, L.P.
Revenue
Revenue	$ 1,759	$ 505	$ 4,633	$ 2,031