Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income (loss)	$ 43,189	$ 6,529	$ (4,715)
Adjustments to reconcile net loss to net cash from operating activities:
Depreciation and amortization	198,731	198,579	219,110
Amortization of deferred financing costs	4,676	6,208	4,991
Amortization of debt discount/(premium), net	2,480	1,760	1,567
Amortization of stock compensation costs	6,998	5,685	5,282
Share-based compensation expense relating to awards withheld for employee taxes upon vesting of share awards	(1,062)	(2,493)	(1,012)
Recognized hedge activity	0	2,985	0
Straight-line rent income	(20,136)	(23,566)	(20,298)
Amortization of above (below) Market Leases, Net	(7,170)	(6,084)	(5,384)
Straight-line ground rent expense	1,509	1,897	1,924
Provision for doubtful accounts	2,467	2,198	1,924
Net gain on sale of interests in real estate	(29,166)	(34,774)	(10,008)
Loss on real estate venture formation	0	950	222
Net gain from remeasurement of investments in real estate ventures	6,866	0	0
Net gain on real estate venture transactions	(3,683)	0	0
Loss on early extinguishment of debt	2,119	22,002	2,776
Historic tax credit transaction income	(11,853)	(11,840)	(12,026)
Real estate venture income in excess of distributions	(2,014)	(1,517)	(1,175)
Cumulative interest accretion of repayments of unsecured notes	0	0	(4,005)
Contributions from historic tax credit transaction, net of deferred costs	0	0	2,694
Deferred financing obligation	(974)	(1,803)	0
Changes in assets and liabilities:
Accounts receivable	(4,048)	262	(856)
Other assets	5,440	4,244	(3,851)
Accounts payable and accrued expenses	(526)	(8,355)	7,732
Deferred income, gains and rent	3,758	(2,167)	(7,220)
Other liabilities	(385)	(1,590)	(425)
Net cash from operating activities	183,484	159,110	177,247
Cash flows from investing activities:
Acquisition of properties	(161,604)	(77,555)	(40,674)
Investments in Available-for-sale Securities, Debt	0	(105,250)	0
Proceeds from the sale of available-for-sale securities	0	105,250	0
Sales of properties, net	423,480	170,918	155,956
Distribution of sales proceeds of real estate ventures	16,963	0	0
Proceeds from repayment of mortgage notes receivable	200	23,364	0
Capital expenditures for tenant improvements	(109,357)	(86,986)	(130,482)
Capital expenditures for redevelopments	(6,265)	(11,964)	(674)
Capital expenditures for developments	(5,490)	(162)	0
Payments for (Proceeds from) Other Investing Activities	1,976	0	0
Advances for purchase of tenant assets, net of repayments	(127)	270	1,365
Loan proceeds from an unconsolidated Real Estate Venture partner	0	566	1,388
Loan provided to unconsolidated Real Estate Venture partner	0	0	(1,122)
Investment in unconsolidated Real Estate Ventures	(33,069)	(65,354)	(5,277)
Increase (Decrease) in Restricted Cash	1,902	(1,827)	1,502
Cash distributions from unconsolidated Real Estate Ventures in excess of cumulative equity income	7,496	5,109	10,316
Leasing costs	(31,397)	(31,243)	(38,461)
Net cash from (used in) investing activities	104,708	(74,864)	(46,163)
Cash flows from financing activities:
Proceeds from New Unsecured Term Loans	0	600,000	0
Proceeds from Credit Facility	186,000	90,500	706,002
Repayments of Credit Facility	(255,000)	(297,000)	(613,502)
Repayments of mortgage notes payable	(11,268)	(68,513)	(221,856)
Proceeds from unsecured notes	0	248,183	321,448
Deferred financing obligation interest expense	0	935	0
Net Proceeds from Issuance of Common Stock	181,527	0	7,930
Net Proceeds from Issuance of Preferred Stock and Preference Stock	0	96,237	0
Redemption of preferred units	0	(108,536)	0
Cash used in redemption of partnership units	0	(9,676)	0
Repayments from unsecured notes	(31,369)	(338,097)	(105,381)
Repayments of unsecured term loan	0	(190,485)	(145,500)
Net settlement of hedge transactions	0	0	(613)
Debt financing costs	(355)	(10,128)	(4,249)
Exercise of stock options	2,381	976	350
Distributions paid to shareholders/unitholders	(97,367)	(96,030)	(89,559)
Distributions to noncontrolling interest	(1,083)	(1,473)	(2,309)
Net cash from (used in) financing activities	(26,534)	(83,107)	(147,239)
Increase (decrease) in cash and cash equivalents	261,658	1,139	(16,155)
Cash and cash equivalents at beginning of period	1,549	410	16,565
Cash and cash equivalents at end of period	263,207	1,549	410
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the years ended December 31, 2013, 2012, and 2011 of $3,137, $2,560, and $1,997, respectively	118,714	137,823	135,210
Supplemental disclosure of non-cash activity:
Change in operating real estate related to a non-cash acquisition of an operating property	(21,649)	0	0
Change in intangible assets, net related to non-cash acquisition of an operating property	(3,517)	0	0
Change in acquired lease intangibles, net related to non-cash acquisition of an operating property	462	0	0
Change in investments in joint venture related to non-cash acquisition of property	13,040	0	0
Change in investments in joint venture related to non-cash disposition of property	(17,628)	0	0
Change in operating real estate related to non-cash adjustment to land	7,752	0	0
Change in mortgage notes payable related to acquisition of an operating property	238,082	0	0
Change in investments in joint venture related to a contribution of land at period end	(6,058)	(15,222)	0
Change in investments in joint venture related to a contribution of services	0	(711)	0
Change in capital expenditures financed through accounts payable at period end	11,703	7,059	(3,896)
Change in capital expenditures financed through retention payable at period end	(204)	566	(6,213)
Change in unfunded tenant allowance	(969)	(1,089)	(1,717)
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Cash flows from operating activities:
Net income (loss)	43,189	6,529	(4,715)
Adjustments to reconcile net loss to net cash from operating activities:
Depreciation and amortization	198,731	198,579	219,110
Amortization of deferred financing costs	4,676	6,208	4,991
Amortization of debt discount/(premium), net	2,480	1,760	1,567
Amortization of stock compensation costs	6,998	5,685	5,282
Share-based compensation expense relating to awards withheld for employee taxes upon vesting of share awards	(1,062)	(2,493)	(1,012)
Recognized hedge activity	0	2,985	0
Straight-line rent income	(20,136)	(23,566)	(20,298)
Amortization of above (below) Market Leases, Net	(7,170)	(6,084)	(5,384)
Straight-line ground rent expense	1,509	1,897	1,924
Provision for doubtful accounts	2,467	2,198	1,924
Net gain on sale of interests in real estate	(29,166)	(34,774)	(10,008)
Loss on real estate venture formation	0	950	222
Net gain from remeasurement of investments in real estate ventures	6,866	0	0
Net gain on real estate venture transactions	(3,683)	0	0
Loss on early extinguishment of debt	2,119	22,002	2,776
Historic tax credit transaction income	(11,853)	(11,840)	(12,026)
Real estate venture income in excess of distributions	(2,014)	(1,517)	(1,175)
Cumulative interest accretion of repayments of unsecured notes	0	0	(4,005)
Contributions from historic tax credit transaction, net of deferred costs	0	0	2,694
Deferred financing obligation	(974)	(1,803)	0
Changes in assets and liabilities:
Accounts receivable	(4,048)	262	(856)
Other assets	5,440	4,244	(3,851)
Accounts payable and accrued expenses	(526)	(8,355)	7,732
Deferred income, gains and rent	3,758	(2,167)	(7,220)
Other liabilities	(385)	(1,590)	(425)
Net cash from operating activities	183,484	159,110	177,247
Cash flows from investing activities:
Acquisition of properties	(161,604)	(77,555)	(40,674)
Investments in Available-for-sale Securities, Debt	0	(105,250)	0
Proceeds from the sale of available-for-sale securities	0	105,250	0
Sales of properties, net	423,480	170,918	155,956
Distribution of sales proceeds of real estate ventures	16,963	0
Proceeds from repayment of mortgage notes receivable	200	23,364	0
Capital expenditures for tenant improvements	(109,357)	(86,986)	(130,482)
Capital expenditures for redevelopments	(6,265)	(11,964)	(674)
Capital expenditures for developments	(5,490)	(162)	0
Payments for (Proceeds from) Other Investing Activities	1,976	0
Advances for purchase of tenant assets, net of repayments	(127)	270	1,365
Loan proceeds from an unconsolidated Real Estate Venture partner	0	566	1,388
Loan provided to unconsolidated Real Estate Venture partner	0	0	(1,122)
Investment in unconsolidated Real Estate Ventures	(33,069)	(65,354)	(5,277)
Increase (Decrease) in Restricted Cash	1,902	(1,827)	1,502
Cash distributions from unconsolidated Real Estate Ventures in excess of cumulative equity income	7,496	5,109	10,316
Leasing costs	(31,397)	(31,243)	(38,461)
Net cash from (used in) investing activities	104,708	(74,864)	(46,163)
Cash flows from financing activities:
Proceeds from New Unsecured Term Loans	0	600,000	0
Proceeds from Credit Facility	186,000	90,500	706,002
Repayments of Credit Facility	(255,000)	(297,000)	(613,502)
Repayments of mortgage notes payable	(11,268)	(68,513)	(221,856)
Proceeds from unsecured notes	0	248,183	321,448
Deferred financing obligation interest expense	0	935	0
Net Proceeds from Issuance of Common Stock	181,527	0	7,930
Net Proceeds from Issuance of Preferred Stock and Preference Stock	0	96,237	0
Redemption of preferred units	0	(108,536)	0
Cash used in redemption of partnership units	0	(9,676)	0
Repayments from unsecured notes	(31,369)	(338,097)	(105,381)
Repayments of unsecured term loan	0	(190,485)	(145,500)
Net settlement of hedge transactions	0	0	(613)
Debt financing costs	(355)	(10,128)	(4,249)
Refund Of Deferred Financing Costs Related To Forward Commitment	0	0	0
Exercise of stock options	2,381	976	350
Distributions paid to shareholders/unitholders	(98,450)	(97,503)	(91,868)
Net cash from (used in) financing activities	(26,534)	(83,107)	(147,239)
Increase (decrease) in cash and cash equivalents	261,658	1,139	(16,155)
Cash and cash equivalents at beginning of period	1,549	410	16,565
Cash and cash equivalents at end of period	263,207	1,549	410
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the years ended December 31, 2013, 2012, and 2011 of $3,137, $2,560, and $1,997, respectively	118,714	137,823	135,210
Supplemental disclosure of non-cash activity:
Change in operating real estate related to a non-cash acquisition of an operating property	(21,649)	0
Change in intangible assets, net related to non-cash acquisition of an operating property	(3,517)	0
Change in acquired lease intangibles, net related to non-cash acquisition of an operating property	462	0
Change in investments in joint venture related to non-cash acquisition of property	13,040	0
Change in investments in joint venture related to non-cash disposition of property	(17,628)	0
Change in operating real estate related to non-cash adjustment to land	7,752	0
Change in mortgage notes payable related to acquisition of an operating property	238,082	0	0
Change in investments in joint venture related to a contribution of land at period end	(6,058)	(15,222)
Change in investments in joint venture related to a contribution of services	0
Change in capital expenditures financed through accounts payable at period end	11,703	7,059	(3,896)
Change in capital expenditures financed through retention payable at period end	(204)	566	(6,213)
Change in unfunded tenant allowance	$ (969)	$ (1,089)	$ (1,717)