Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income (loss)	$ (4,715)	$ (17,606)	$ 8,089
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	219,110	214,776	210,463
Amortization of deferred financing costs	4,991	3,770	5,864
Amortization of debt discount/(premium), net	1,567	831	3,495
Straight-line rent income	(20,298)	(13,705)	(9,116)
Amortization of acquired above (below) market leases to rental renenue, net	(5,384)	(5,960)	(6,661)
Straight-line ground rent expense	1,924	1,647	1,473
Provision for doubtful accounts	1,924	2,479	5,371
Non-cash compensation expense	4,270	4,814	5,200
Recognized hedge activity	0	0	916
Provision for impairment on discontinued operations	0	0	3,700
Real estate venture income in excess of cumulative distributions	(1,175)	(4,648)	(2,512)
Loss on real estate venture formation	222	0	0
Net loss (gain) on sale of interests in real estate	(10,008)	(11,011)	(1,237)
Loss (gain) on early extinguishment of debt	2,776	2,110	(23,176)
Cumulative interest accretion of repayments of unsecured notes	(4,005)	(3,433)	(5,009)
Contributions from historic tax credit transaction, net of deferred costs	2,694	27,396	23,763
Historic tax credit transaction income	(12,026)	0	0
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	(856)	(4,173)	3,746
Other assets	(2,083)	(2,782)	2,373
Accounts payable and accrued expenses	7,732	(7,980)	(4,081)
Deferred income, gains and rent	(7,220)	(6,412)	3,059
Other liabilities	(425)	5,014	(5,315)
Net cash from operating activities	179,015	185,127	220,405
Cash flows from investing activities:
Acquisition of properties	(40,674)	(50,681)	0
Sales of properties, net	155,956	50,089	101,305
Proceeds from repayment of mortgage notes receivable	0	40,000	0
Capital expenditures	(131,156)	(180,943)	(211,892)
Advances for purchase of tenant assets, net of repayments	1,365	(1,715)	0
Loan provided to unconsolidated Real Estate Venture partner	0	(826)	0
Investment in unconsolidated Real Estate Ventures	(5,277)	(5,180)	(14,980)
Escrowed cash	0	0	31,385
Cash distributions from unconsolidated Real Estate Ventures in excess of cumulative equity income	10,316	2,205	13,062
Decrease in cash due to the deconsolidation of variable interest entities	0	(1,382)	0
Leasing costs	(38,461)	(23,503)	(21,429)
Net cash used in investing activities	(47,931)	(171,936)	(102,549)
Cash flows from financing activities:
Proceeds from Credit Facility borrowings	706,002	565,000	983,000
Repayments of Credit Facility borrowings	(613,502)	(474,000)	(1,044,000)
Proceeds from mortgage notes payable	0	256,104	149,800
Repayments of mortgage notes payable	(221,856)	(51,966)	(84,102)
Repayments from unsecured term loan	(145,500)	0	0
Proceeds from unsecured notes	321,448	0	247,030
Repayments of unsecured notes	(105,381)	(276,270)	(514,004)
Proceeds from financing activity	0	0	0
Net settlement of hedge transactions	(613)	0	(5,044)
Debt financing costs	(4,249)	(595)	(24,620)
Refund of deferred financing costs related to forward commitment	0	1,659	0
Net proceeds from issuance of shares/operating units	7,930	70,867	242,332
Exercise of stock/units options	350	37	0
Distributions paid to shareholders/unitholders	(89,559)	(87,345)	(68,914)
Distributions to noncontrolling interest	(2,309)	(1,684)	(1,691)
Net cash from (used in) financing activities	(147,239)	1,807	(120,213)
Increase (decrease) in cash and cash equivalents	(16,155)	14,998	(2,357)
Cash and cash equivalents at beginning of year	16,565	1,567	3,924
Cash and cash equivalents at end of year	410	16,565	1,567
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the years ended December 31, 2011, 2010 and 2009 of $1,997, $10,385, and $8,893, respectively	135,210	135,206	139,636
Supplemental disclosure of non-cash activity:
Note receivable issued related to the sale of the two Trenton properties, net of $12.9 million deferred gain	0	0	9,600
Settlement of note receivable through foreclosure of a parcel of land	0	(2,795)	0
Proceeds from mortgage notes payable retained by lender and included in other assets (see Note 7)	0	396	0
Change in capital expenditures financed through accounts payable at period end	(3,896)	(5,126)	7,086
Change in capital expenditures financed through retention payable at period end	(6,213)	(2,066)	5,862
Change in unfunded tenant allowance	(1,717)	0	5,986
Change in real estate investments due to the deconsolidation of variable interest entities	0	(37,126)	0
Change in mortgage notes payable due to the deconsolidation of variable interest entities	0	(42,877)	0
Change in non-controlling interest from issuance of limited partnership units (see Note 3)	0	77,733	0
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Cash flows from operating activities:
Net income (loss)	(4,715)	(17,606)	8,089
Adjustments to reconcile net income (loss) to net cash from operating activities:
Depreciation and amortization	219,110	214,776	210,463
Amortization of deferred financing costs	4,991	3,770	5,864
Amortization of debt discount/(premium), net	1,567	831	3,495
Straight-line rent income	(20,298)	(13,705)	(9,116)
Amortization of acquired above (below) market leases to rental renenue, net	(5,384)	(5,960)	(6,661)
Straight-line ground rent expense	1,924	1,647	1,473
Provision for doubtful accounts	1,924	2,479	5,371
Non-cash compensation expense	4,270	4,814	5,200
Recognized hedge activity	0	0	916
Provision for impairment on discontinued operations	0	0	3,700
Real estate venture income in excess of cumulative distributions	(1,175)	(4,648)	(2,512)
Loss on real estate venture formation	222	0	0
Net loss (gain) on sale of interests in real estate	(10,008)	(11,011)	(1,237)
Loss (gain) on early extinguishment of debt	2,776	2,110	(23,176)
Cumulative interest accretion of repayments of unsecured notes	(4,005)	(3,433)	(5,009)
Contributions from historic tax credit transaction, net of deferred costs	2,694	27,396	23,763
Historic tax credit transaction income	(12,026)	0	0
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	(856)	(4,173)	3,746
Other assets	(2,083)	(2,782)	2,373
Accounts payable and accrued expenses	7,732	(7,980)	(4,081)
Deferred income, gains and rent	(7,220)	(6,412)	3,059
Other liabilities	(425)	5,014	(5,315)
Net cash from operating activities	179,015	185,127	220,405
Cash flows from investing activities:
Acquisition of properties	(40,674)	(50,681)	0
Sales of properties, net	155,956	50,089	101,305
Proceeds from repayment of mortgage notes receivable	0	40,000	0
Capital expenditures	(131,156)	(180,943)	(211,892)
Advances for purchase of tenant assets, net of repayments	1,365	(1,715)	0
Loan provided to unconsolidated Real Estate Venture partner	0	(826)	0
Investment in unconsolidated Real Estate Ventures	(5,277)	(5,180)	(14,980)
Escrowed cash	0	0	31,385
Cash distributions from unconsolidated Real Estate Ventures in excess of cumulative equity income	10,316	2,205	13,062
Decrease in cash due to the deconsolidation of variable interest entities	0	(1,382)	0
Leasing costs	(38,461)	(23,503)	(21,429)
Net cash used in investing activities	(47,931)	(171,936)	(102,549)
Cash flows from financing activities:
Proceeds from Credit Facility borrowings	706,002	565,000	983,000
Repayments of Credit Facility borrowings	(613,502)	(474,000)	(1,044,000)
Proceeds from mortgage notes payable	0	256,104	149,800
Repayments of mortgage notes payable	(221,856)	(51,966)	(84,102)
Repayments from unsecured term loan	(145,500)	0	0
Proceeds from unsecured notes	321,448	0	247,030
Repayments of unsecured notes	(105,381)	(276,270)	(514,004)
Proceeds from financing activity	0	0	0
Net settlement of hedge transactions	(613)	0	(5,044)
Debt financing costs	(4,249)	(595)	(24,620)
Refund of deferred financing costs related to forward commitment	0	1,659	0
Net proceeds from issuance of shares/operating units	7,930	70,867	242,332
Exercise of stock/units options	350	37	0
Distributions paid to shareholders/unitholders	(91,868)	(89,029)	(70,605)
Net cash from (used in) financing activities	(147,239)	1,807	(120,213)
Increase (decrease) in cash and cash equivalents	(16,155)	14,998	(2,357)
Cash and cash equivalents at beginning of year	16,565	1,567	3,924
Cash and cash equivalents at end of year	410	16,565	1,567
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the years ended December 31, 2011, 2010 and 2009 of $1,997, $10,385, and $8,893, respectively	135,210	135,206	139,636
Supplemental disclosure of non-cash activity:
Note receivable issued related to the sale of the two Trenton properties, net of $12.9 million deferred gain	0	0	9,600
Settlement of note receivable through foreclosure of a parcel of land	0	(2,795)	0
Proceeds from mortgage notes payable retained by lender and included in other assets (see Note 7)	0	396	0
Change in capital expenditures financed through accounts payable at period end	(3,896)	(5,126)	7,086
Change in capital expenditures financed through retention payable at period end	(6,213)	(2,066)	5,862
Change in unfunded tenant allowance	(1,717)	0	5,986
Change in real estate investments due to the deconsolidation of variable interest entities	0	(37,126)	0
Change in mortgage notes payable due to the deconsolidation of variable interest entities	0	(42,877)	0
Change in non-controlling interest from issuance of limited partnership units (see Note 3)	$ 0	$ 77,733	$ 0