10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

_________________________

FORM 10-Q

_________________________

(Mark One)

þ	Quarterly Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
	For the quarterly period ended September 30, 2013

or

o	Transition Report Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934
	For the transition period from                      to

Commission file number

001-9106 (Brandywine Realty Trust)

000-24407 (Brandywine Operating Partnership, L.P.)

_________________________

Brandywine Realty Trust

Brandywine Operating Partnership, L.P.

(Exact name of registrant as specified in its charter)

_________________________

MARYLAND (Brandywine Realty Trust)	23-2413352
DELAWARE (Brandywine Operating Partnership L.P.)	23-2862640
(State or other jurisdiction of	(I.R.S. Employer
Incorporation or organization)	Identification No.)
555 East Lancaster Avenue
Radnor, Pennsylvania	19087
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code (610) 325-5600

_________________________

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.

Brandywine Realty Trust	Yes þ No o
Brandywine Operating Partnership, L.P.	Yes þ No o

1

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).

Brandywine Realty Trust	Yes þ No o
Brandywine Operating Partnership, L.P.	Yes þ No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer”, "accelerated filer", and "smaller reporting company" in Rule 12b-2 of the Exchange Act.

Brandywine Realty Trust:

Large accelerated filer þ Accelerated filer o Non-accelerated filer o Smaller reporting company o

Brandywine Operating Partnership, L.P.:

Large accelerated filer o Accelerated filer o Non-accelerated filer þ Smaller reporting company o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Brandywine Realty Trust	Yes o No þ
Brandywine Operating Partnership, L.P.	Yes o No þ

A total of 156,710,290 Common Shares of Beneficial Interest, par value $0.01 per share of Brandywine Realty Trust, were outstanding as of October 29, 2013.

2

EXPLANATORY NOTE

This report combines the quarterly reports on Form 10-Q for the period ended September 30, 2013 of Brandywine Realty Trust (the “Parent Company”) and Brandywine Operating Partnership L.P. (the “Operating Partnership”). The Parent Company is a Maryland real estate investment trust, or REIT, that owns its assets and conducts its operations through the Operating Partnership, a Delaware limited partnership, and subsidiaries of the Operating Partnership. The Parent Company, the Operating Partnership and their consolidated subsidiaries are collectively referred to in this report as the “Company”. In addition, as used in this report, terms such as “we”, “us”, and “our” may refer to the Company, the Parent Company, or the Operating Partnership.

The Parent Company is the sole general partner of the Operating Partnership and, as of September 30, 2013, owned a 98.8% interest in the Operating Partnership. The remaining 1.2% interest consists of common units of limited partnership interest issued by the Operating Partnership to third parties in exchange for contributions of properties to the Operating Partnership. As the sole general partner of the Operating Partnership, the Parent Company has full and complete authority over the Operating Partnership’s day-to-day operations and management.

The Company believes that combining the quarterly reports on Form 10-Q of the Parent Company and the Operating Partnership into a single report will result in the following benefits:

• facilitate a better understanding by the investors of the Parent Company and the Operating Partnership by enabling them to view the business as a whole in the same manner as management views and operates the business;

• remove duplicative disclosures and provide a more straightforward presentation in light of the fact that a substantial portion of the disclosure applies to both the Parent Company and the Operating Partnership; and

• create time and cost efficiencies through the preparation of one combined report instead of two separate reports.

Management operates the Parent Company and the Operating Partnership as one enterprise. The management of the Parent Company consists of the same members as the management of the Operating Partnership.

There are few differences between the Parent Company and the Operating Partnership, which are reflected in the footnote disclosures in this report. The Company believes it is important to understand the differences between the Parent Company and the Operating Partnership in the context of how these entities operate as an interrelated consolidated company. The Parent Company is a REIT, whose only material asset is its ownership of partnership interests of the Operating Partnership. As a result, the Parent Company does not conduct business itself, other than acting as the sole general partner of the Operating Partnership, issuing equity from time to time and guaranteeing the debt obligations of the Operating Partnership. The Operating Partnership holds substantially all the assets of the Company and directly or indirectly holds the ownership interests in the Company’s real estate ventures. The Operating Partnership conducts the operations of the Company’s business and is structured as a partnership with no publicly traded equity. Except for net proceeds from equity issuances by the Parent Company, which are contributed to the Operating Partnership in exchange for partnership units, the Operating Partnership generates the capital required by the Company’s business through the Operating Partnership’s operations, by the Operating Partnership’s incurrence of indebtedness (directly and through subsidiaries) and through the issuance of partnership units of the Operating Partnership or equity interests in subsidiaries of the Operating Partnership.

The equity and non-controlling interests in the Parent Company and the Operating Partnership’s equity are the main areas of difference between the consolidated financial statements of the Parent Company and the Operating Partnership. The common units of limited partnership interest in the Operating Partnership are accounted for as partners’ equity in the Operating Partnership’s financial statements while the common units of limited partnership interests held by parties other than the Parent Company are presented as non-controlling interests in the Parent Company’s financial statements. The differences between the Parent Company and the Operating Partnership’s equity relate to the differences in the equity issued at the Parent Company and Operating Partnership levels.

To help investors understand the significant differences between the Parent Company and the Operating Partnership, this report presents the following as separate notes or sections for each of the Parent Company and the Operating Partnership:

• Consolidated Financial Statements;

• Parent Company’s and Operating Partnership’s Equity; and

• Liquidity and Capital Resources in the Management’s Discussion and Analysis of Financial Condition and Results of Operations.

3

This report also includes separate Item 4. (Controls and Procedures) disclosures and separate Exhibit 31 and 32 certifications for each of the Parent Company and the Operating Partnership in order to establish that the Chief Executive Officer and the Chief Financial Officer of each entity have made the requisite certifications and that the Parent Company and Operating Partnership are compliant with Rule 13a-15 or Rule 15d-15 of the Securities Exchange Act of 1934, as amended, and 18 U.S.C. § 1350.

In order to highlight the differences between the Parent Company and the Operating Partnership, the separate sections in this report for the Parent Company and the Operating Partnership specifically refer to the Parent Company and the Operating Partnership. In the sections that combine disclosures of the Parent Company and the Operating Partnership, this report refers to such disclosures as those of the Company. Although the Operating Partnership is generally the entity that directly or indirectly enters into contracts and real estate ventures and holds assets and debt, reference to the Company is appropriate because the business is one enterprise and the Parent Company operates the business through the Operating Partnership.

As general partner with control of the Operating Partnership, the Parent Company consolidates the Operating Partnership for financial reporting purposes, and the Parent Company does not have significant assets other than its investment in the Operating Partnership. Therefore, the assets and liabilities of the Parent Company and the Operating Partnership are the same on their respective financial statements. The separate discussions of the Parent Company and the Operating Partnership in this report should be read in conjunction with each other to understand the results of the Company’s operations on a consolidated basis and how management operates the Company.

4

TABLE OF CONTENTS

	Page
PART I — FINANCIAL INFORMATION
Item 1. Financial Statements
Brandywine Realty Trust
Financial Statements of Brandywine Realty Trust (unaudited)
Consolidated Balance Sheets as of September 30, 2013 and December 31, 2012	7
Consolidated Statements of Operations for the three and nine-month periods ended September 30, 2013 and 2012	8
Consolidated Statements of Comprehensive Income for the three and nine-month periods ended September 30, 2013 and 2012	9
Consolidated Statements of Beneficiaries’ Equity for the nine-month periods ended September 30, 2013 and 2012	10
Consolidated Statements of Cash Flows for the nine-month periods ended September 30, 2013 and 2012	12
Brandywine Operating Partnership, L.P.
Financial Statements of Brandywine Operating Partnership, L.P. (unaudited)
Consolidated Balance Sheets as of September 30, 2013 and December 31, 2012	14
Consolidated Statements of Operations for the three and nine-month periods ended September 30, 2013 and 2012	15
Consolidated Statements of Comprehensive Income for the three and nine-month periods ended September 30, 2013 and 2012	16
Consolidated Statements of Cash Flows for the nine-month periods ended September 30, 2013 and 2012	17
Notes to Unaudited Consolidated Financial Statements	19
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations	49
Item 3. Quantitative and Qualitative Disclosures about Market Risk	73
Item 4. Controls and Procedures	74
PART II — OTHER INFORMATION
Item 1. Legal Proceedings	75
Item 1A. Risk Factors	75
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds	75
Item 3. Defaults Upon Senior Securities	75
Item 4. Mine Safety Disclosures	75
Item 5. Other Information	75
Item 6. Exhibits	76
Signatures	77
Exhibit 31.1
Exhibit 31.2
Exhibit 31.3
Exhibit 31.4
Exhibit 32.1
Exhibit 32.2
Exhibit 32.3
Exhibit 32.4

5

 EX-101 INSTANCE DOCUMENT

 EX-101 SCHEMA DOCUMENT

 EX-101 CALCULATION LINKBASE DOCUMENT

 EX-101 LABELS LINKBASE DOCUMENT

 EX-101 PRESENTATION LINKBASE DOCUMENT

 EX-101 DEFINITION LINKBASE DOCUMENT

Filing Format

This combined Form 10-Q is being filed separately by Brandywine Realty Trust and Brandywine Operating Partnership, L.P.

6

PART I - FINANCIAL INFORMATION

Item 1. — Financial Statements

BRANDYWINE REALTY TRUST

CONSOLIDATED BALANCE SHEETS

(unaudited, in thousands, except share and per share information)

	September 30, 2013			December 31, 2012
	(unaudited)
ASSETS
Real estate investments:
Operating properties	$	4,631,910		$	4,726,169
Accumulated depreciation	(998,409		)	(954,665		)
Operating real estate investments, net	3,633,501			3,771,504
Construction-in-progress	52,702			48,950
Land inventory	94,097			102,439
Total real estate investments, net	3,780,300			3,922,893
Cash and cash equivalents	185,517			1,549
Accounts receivable, net	13,718			13,232
Accrued rent receivable, net	128,232			122,066
Assets held for sale, net	2,371			—
Investment in real estate ventures, at equity	194,572			193,555
Deferred costs, net	126,260			122,243
Intangible assets, net	54,457			70,620
Notes receivable	7,026			7,226
Other assets	65,689			53,325
Total assets	$	4,558,142		$	4,506,709
LIABILITIES AND BENEFICIARIES’ EQUITY
Mortgage notes payable	$	434,895		$	442,974
Unsecured credit facility	—			69,000
Unsecured term loans	450,000			450,000
Unsecured senior notes, net of discounts	1,492,296			1,503,356
Accounts payable and accrued expenses	89,087			71,579
Distributions payable	25,579			23,652
Deferred income, gains and rent	69,637			82,947
Acquired lease intangibles, net	28,500			33,859
Other liabilities	46,990			55,826
Total liabilities	2,636,984			2,733,193
Commitments and contingencies (Note 17)
Brandywine Realty Trust’s equity:
Preferred Shares (shares authorized-20,000,000):
6.90% Series E Preferred Shares, $0.01 par value; issued and outstanding- 4,000,000 in 2013 and 2012	40			40
Common Shares of Brandywine Realty Trust’s beneficial interest, $0.01 par value; shares authorized 200,000,000; 156,703,790 and 143,538,733 issued and outstanding in 2013 and 2012, respectively	1,565			1,434
Additional paid-in capital	2,970,576			2,780,194
Deferred compensation payable in common shares	5,431			5,352
Common shares in grantor trust, 313,023 in 2013 and 290,745 in 2012	(5,431		)	(5,352		)
Cumulative earnings	501,735			479,734
Accumulated other comprehensive loss	(5,825		)	(15,918		)
Cumulative distributions	(1,567,202		)	(1,493,206		)
Total Brandywine Realty Trust’s equity	1,900,889			1,752,278
Non-controlling interests	20,269			21,238
Total equity	1,921,158			1,773,516
Total liabilities and equity	$	4,558,142		$	4,506,709

The accompanying notes are an integral part of these consolidated financial statements.

7

BRANDYWINE REALTY TRUST

CONSOLIDATED STATEMENTS OF OPERATIONS

(unaudited, in thousands, except share and per share information)

	Three-month periods ended						Nine-month periods ended
	September 30,						September 30,
	2013			2012			2013			2012
Revenue:
Rents	$	116,479		$	108,658		$	347,680		$	327,362
Tenant reimbursements	20,699			20,294			60,615			57,179
Termination fees	2,040			931			2,946			2,522
Third party management fees, labor reimbursement and leasing	3,263			3,007			9,652			9,021
Other	975			1,630			3,305			4,029
Total revenue	143,456			134,520			424,198			400,113
Operating Expenses:
Property operating expenses	40,661			38,783			119,522			112,961
Real estate taxes	14,190			13,486			42,706			40,430
Third party management expenses	1,317			1,298			4,105			3,812
Depreciation and amortization	50,613			46,955			149,423			142,262
General and administrative expenses	6,436			6,080			20,322			18,209
Total operating expenses	113,217			106,602			336,078			317,674
Operating income	30,239			27,918			88,120			82,439
Other Income (Expense):
Interest income	268			311			448			2,631
Historic tax credit transaction income	11,853			11,840			11,853			11,840
Interest expense	(30,338		)	(32,620		)	(91,689		)	(99,745		)
Interest expense — amortization of deferred financing costs	(1,158		)	(1,218		)	(3,502		)	(3,790		)
Interest expense — financing obligation	(264		)	(230		)	(693		)	(608		)
Equity in income of real estate ventures	714			500			3,757			1,382
Gain from remeasurement of investment in a real estate venture	—			—			7,847			—
Net gain on real estate venture transactions	—			—			3,683			—
Net loss on sale of undepreciated real estate	(129		)	—			(129		)	—
Loss on real estate venture formation	—			(950		)	—			(950		)
Loss on early extinguishment of debt	(11		)	(51		)	(1,127		)	(1,549		)
Income (Loss) from continuing operations	11,174			5,500			18,568			(8,350		)
Discontinued operations:
Income (Loss) from discontinued operations	(70		)	1,649			590			6,803
Net gain (loss) on disposition of discontinued operations	(16		)	9,940			3,029			34,774
Total discontinued operations	(86		)	11,589			3,619			41,577
Net income	11,088			17,089			22,187			33,227
Net (income) loss from discontinued operations attributable to non-controlling interests — LP units	1			(211		)	(48		)	(760		)
Net (income) loss attributable to non-controlling interests — LP units	(106		)	(49		)	(147		)	335
Net income attributable to non-controlling interests	(105		)	(260		)	(195		)	(425		)
Net income attributable to Brandywine Realty Trust	10,983			16,829			21,992			32,802
Distribution to Preferred Shares	(1,725		)	(2,785		)	(5,175		)	(7,832		)
Preferred share redemption charge	—			—			—			(2,090		)
Amount allocated to unvested restricted shareholders	(85		)	(95		)	(278		)	(286		)
Net income attributable to Common Shareholders of Brandywine Realty Trust	$	9,173		$	13,949		$	16,539		$	22,594
Basic income (loss) per Common Share:
Continuing operations	$	0.06		$	0.02		$	0.09		$	(0.13	)
Discontinued operations	—			0.08			0.02			0.29
	$	0.06		$	0.10		$	0.11		$	0.16
Diluted income (loss) per Common Share:
Continuing operations	$	0.06		$	0.02		$	0.09		$	(0.13	)
Discontinued operations	—			0.08			0.02			0.29
	$	0.06		$	0.10		$	0.11		$	0.16
Basic weighted average shares outstanding	156,703,348			143,424,485			151,933,441			143,182,911
Diluted weighted average shares outstanding	157,992,082			144,128,010			153,142,825			143,182,911
Net income (loss) attributable to Brandywine Realty Trust
Net income (loss) from continuing operations	$	11,068		$	5,451		$	18,421		$	(8,015	)
Income (Loss) from discontinued operations	(85		)	11,378			3,571			40,817
Net income	$	10,983		$	16,829		$	21,992		$	32,802

The accompanying notes are an integral part of these consolidated financial statements.

8

BRANDYWINE REALTY TRUST

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(unaudited, in thousands)

	Three-month periods ended						Nine-month periods ended
	September 30,						September 30,
	2013			2012			2013			2012
Net income	$	11,088		$	17,089		$	22,187		$	33,227
Comprehensive income (loss):
Unrealized gain (loss) on derivative financial instruments	(1,302		)	(4,222		)	9,978			(14,780		)
Reclassification of realized losses on derivative financial instruments to operations, net (1)	64			76			232			200
Unrealized gain on available-for-sale securities	—			65			—			—
Total comprehensive income (loss)	(1,238		)	(4,081		)	10,210			(14,580		)
Comprehensive income	9,850			13,008			32,397			18,647
Comprehensive (income) attributable to non-controlling interest	(91		)	(186		)	(312		)	(158		)
Comprehensive income (loss) attributable to Brandywine Realty Trust	$	9,759		$	12,822		$	32,085		$	18,489

(1) Amounts reclassified from comprehensive income to interest expense within the Consolidated Statements of Operations.

The accompanying notes are an integral part of these consolidated financial statements.

9

BRANDYWINE REALTY TRUST

CONSOLIDATED STATEMENTS OF BENEFICIARIES’ EQUITY

For the nine-month periods ended September 30, 2013 and September 30, 2012

(unaudited, in thousands, except number of shares)

September 30, 2013

	Number of Preferred Shares	Par Value of Preferred Shares		Number of Common Shares		Number of Rabbi Trust/Deferred Compensation Shares		Common Shares of Brandywine Realty Trust’s beneficial interest		Additional Paid-in Capital			Deferred Compensation Payable in Common Shares		Common Shares in Grantor Trust			Cumulative Earnings		Accumulated Other Comprehensive Income (Loss)			Cumulative Distributions			Non-Controlling Interests			Total
BALANCE, December 31, 2012	4,000,000	$	40	143,538,733		290,745		$	1,434	$	2,780,194		$	5,352	$	(5,352	)	$	479,734	$	(15,918	)	$	(1,493,206	)	$	21,238		$	1,773,516
Net income																		21,992								195			22,187
Comprehensive income																				10,093						117			10,210
Issuance of Common Shares of Beneficial Interest				12,650,000				127		181,907																			182,034
Equity issuance costs										(382		)																	(382		)
Conversion of LP Units to Common Shares				81,998				1		1,240																(1,241		)	—
Bonus Share Issuance				27,918						361																			361
Vesting of Restricted Shares				147,495		7,050		2		(904		)																	(902		)
Restricted Share Amortization										2,565																			2,565
Vesting of Restricted Performance Units				53,134		27,067				(160		)																	(160		)
Restricted Performance Units Amortization										3,718																			3,718
Restricted Share Forfeitures																		9											9
Exercise of Stock Options				207,941				1		2,237																			2,238
Stock Option Amortization										546																			546
Share Issuance from/to Deferred Compensation Plan				(4,838	)	(11,839	)						79		(79		)												—
Trustee Fees Paid in Shares				1,409						20																			20
Adjustment to Non-controlling Interest										(766		)														766			—
Preferred Share distributions																							(5,175		)				(5,175		)
Distributions declared ($0.15 per share)																							(68,821		)	(806		)	(69,627		)
BALANCE, September 30, 2013	4,000,000	$	40	156,703,790		313,023		$	1,565	$	2,970,576		$	5,431	$	(5,431	)	$	501,735	$	(5,825	)	$	(1,567,202	)	$	20,269		$	1,921,158

The accompanying notes are an integral part of these consolidated financial statements.

10

September 30, 2012

	Number of Preferred Shares		Par Value of Preferred Shares			Number of Common Shares		Number of Rabbi Trust/Deferred Compensation Shares		Common Shares of Brandywine Realty Trust’s beneficial interest		Additional Paid-in Capital			Deferred Compensation Payable in Common Shares			Common Shares in Grantor Trust			Cumulative Earnings			Accumulated Other Comprehensive Income (Loss)			Cumulative Distributions			Non-Controlling Interests			Total
BALANCE, December 31, 2011	4,300,000		$	43		142,690,755		292,646		$	1,424	$	2,776,197		$	5,631		$	(5,631	)	$	477,338		$	(6,079	)	$	(1,392,332	)	$	33,105		$	1,889,696
Net income																					32,804									423			33,227
Comprehensive loss																								(14,377		)				(203		)	(14,580		)
Issuance of Preferred Shares	4,000,000		40									96,810																					96,850
Preferred Share Issuance Costs												(610		)																			(610		)
Redemption of Preferred Shares	(2,000,000	)	(20		)							(47,890		)																			(47,910		)
Conversion of LP Units to Common Shares						20,464				1		149									(49		)							(332		)	(231		)
Bonus Share Issuance						35,703						387																					387
Vesting of Restricted Shares						280,851		9,036		3		(1,294		)																			(1,291		)
Restricted Share Amortization												2,138																					2,138
Vesting of Restricted Performance Units						249,797				2		(1,331		)																			(1,329		)
Restricted Performance Units Amortization												1,926																					1,926
Exercise of Stock Options						165,159				2		746																					748
Stock Option Amortization												1,121																					1,121
Share Issuance from/to Deferred Compensation Plan						(5,564	)	(10,937	)						(279		)	279															—
Trustee Fees Paid in Shares						1,336						15																					15
Adjustment to Non-controlling Interest												358																		(347		)	11
Preferred Share distributions																											(7,832		)				(7,832		)
Preferred Share redemption charges																											(2,090		)				(2,090		)
Distributions declared ($0.15 per share)																											(64,804		)	(1,233		)	(66,037		)
BALANCE, September 30, 2012	6,300,000		$	63		143,438,501		290,745		$	1,432	$	2,828,722		$	5,352		$	(5,352	)	$	510,093		$	(20,456	)	$	(1,467,058	)	$	31,413		$	1,884,209

The accompanying notes are an integral part of these consolidated financial statements.

11

BRANDYWINE REALTY TRUST

CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited, in thousands)

	Nine-month periods ended
	September 30,
	2013			2012
Cash flows from operating activities:
Net income	$	22,187		$	33,227
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	151,066			150,362
Amortization of deferred financing costs	3,502			3,790
Amortization of debt discount/(premium), net	1,112			1,095
Amortization of stock compensation costs	5,510			3,740
Shares used for employee taxes upon vesting of share awards	(1,062		)	(2,232		)
Straight-line rent income	(16,337		)	(17,792		)
Amortization of acquired above (below) market leases to rental revenue, net	(5,372		)	(4,468		)
Straight-line ground rent expense	1,286			1,423
Provision for doubtful accounts	1,777			1,363
Net gain on sale of interests in real estate	(3,044		)	(34,773		)
Loss on real estate venture formation	—			950
Net gain on real estate venture transactions	(3,683		)	—
Gain from remeasurement of investment in a real estate venture	(7,847		)	—
Loss on early extinguishment of debt	1,127			1,549
Historic tax credit transaction income	(11,853		)	(11,840		)
Real estate venture income in excess of distributions	(2,371		)	(1,024		)
Deferred financing obligation	(1,392		)	(1,314		)
Changes in assets and liabilities:
Accounts receivable	(287		)	1,580
Other assets	(5,758		)	(7,200		)
Accounts payable and accrued expenses	14,684			9,565
Deferred income, gains and rent	1,265			(4,681		)
Other liabilities	1,718			(1,175		)
Net cash from operating activities	146,228			122,145
Cash flows from investing activities:
Acquisition of properties	(20,758		)	(9,226		)
Investments in available-for-sale securities	—			(98,250		)
Proceeds from the sale of available-for-sale securities	—			98,250
Sales of properties, net	145,931			170,918
Distribution of sales proceeds from real estate ventures	16,963			—
Proceeds from repayment of mortgage notes receivable	200			23,930
Capital expenditures for tenant improvements	(64,481		)	(64,527		)
Capital expenditures for redevelopments	(5,288		)	(9,122		)
Capital expenditures for developments	(5,399		)	—
Reimbursement from real estate venture for pre-formation development costs	1,976			—
Advances for purchase of tenant assets, net of repayments	(420		)	(13		)
Investment in unconsolidated real estate ventures	(30,142		)	(49,763		)
Cash distributions from unconsolidated real estate ventures	3,661			2,779
Leasing costs	(25,704		)	(22,111		)
Net cash from investing activities	16,539			42,865
Cash flows from financing activities:
Proceeds from Unsecured Term Loans	—			600,000
Proceeds from Credit Facility borrowings	186,000			21,500
Repayments of Credit Facility borrowings	(255,000		)	(297,000		)
Repayments of mortgage notes payable	(8,351		)	(9,209		)
Deferred financing obligation non-cash interest expense	697			701
Net proceeds from issuance of common shares	181,527			—
Net proceeds from issuance of preferred shares	—			96,240
Redemption of preferred shares	—			(50,188		)

12

Repayments of unsecured notes	(13,027		)	(167,841		)
Repayments of unsecured term loan	—			(37,500		)
Net settlement of hedge transactions	—			(74		)
Debt financing costs	(6		)	(8,462		)
Exercise of stock options	2,240			748
Distributions paid to shareholders	(72,061		)	(71,523		)
Distributions to noncontrolling interest	(818		)	(1,196		)
Net cash from financing activities	21,201			76,196
Increase in cash and cash equivalents	183,968			241,206
Cash and cash equivalents at beginning of period	1,549			410
Cash and cash equivalents at end of period	$	185,517		$	241,616
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the nine months ended September 30, 2013 and 2012 of $2,012 and $1,978, respectively	$	76,528		$	83,618
Supplemental disclosure of non-cash activity:
Change in operating real estate related to a non-cash acquisition of an operating property	(21,649		)	—
Change in intangible assets, net related to non-cash acquisition of an operating property	(3,517		)	—
Change in acquired lease intangibles, net related to non-cash acquisition of an operating property	462			—
Change in investments in joint venture related to non-cash acquisition of property	13,040			—
Change in operating real estate related to non-cash adjustment to land	(4,386		)	—
Change in investments in real estate ventures related to a contribution of land	(6,058		)	—
Change in capital expenditures financed through accounts payable at period end	1,210			(1,270		)
Change in capital expenditures financed through retention payable at period end	(736		)	284
Change in unfunded tenant allowance	(811		)	(1,411		)

The accompanying notes are an integral part of these consolidated financial statements

13

BRANDYWINE OPERATING PARTNERSHIP, L.P.

CONSOLIDATED BALANCE SHEETS

(unaudited, in thousands, except unit and per unit information)

	September 30, 2013			December 31, 2012
	(unaudited)
ASSETS
Real estate investments:
Operating properties	$	4,631,910		$	4,726,169
Accumulated depreciation	(998,409		)	(954,665		)
Operating real estate investments, net	3,633,501			3,771,504
Construction-in-progress	52,702			48,950
Land inventory	94,097			102,439
Total real estate investments, net	3,780,300			3,922,893
Cash and cash equivalents	185,517			1,549
Accounts receivable, net	13,718			13,232
Accrued rent receivable, net	128,232			122,066
Assets held for sale, net	2,371			—
Investment in real estate ventures, at equity	194,572			193,555
Deferred costs, net	126,260			122,243
Intangible assets, net	54,457			70,620
Notes receivable	7,026			7,226
Other assets	65,689			53,325
Total assets	$	4,558,142		$	4,506,709
LIABILITIES AND EQUITY
Mortgage notes payable	$	434,895		$	442,974
Unsecured credit facility	—			69,000
Unsecured term loans	450,000			450,000
Unsecured senior notes, net of discounts	1,492,296			1,503,356
Accounts payable and accrued expenses	89,087			71,579
Distributions payable	25,579			23,652
Deferred income, gains and rent	69,637			82,947
Acquired lease intangibles, net	28,500			33,859
Other liabilities	46,990			55,826
Total liabilities	2,636,984			2,733,193
Commitments and contingencies (Note 17)
Redeemable limited partnership units at redemption value; 1,763,739 and 1,845,737 issued and outstanding in 2013 and 2012, respectively	26,290			26,777
Brandywine Operating Partnership, L.P.’s equity:
6.90% Series E-Linked Preferred Mirror Units; issued and outstanding- 4,000,000 in 2013 and 2012	96,850			96,850
General Partnership Capital, 156,703,790 and 143,538,733 units issued and outstanding in 2013 and 2012, respectively	1,804,378			1,666,341
Accumulated other comprehensive loss	(6,360		)	(16,452		)
Total Brandywine Operating Partnership, L.P.’s equity	1,894,868			1,746,739
Total liabilities and partners’ equity	$	4,558,142		$	4,506,709

The accompanying notes are an integral part of these consolidated financial statements.

14

BRANDYWINE OPERATING PARTNERSHIP, L.P.

CONSOLIDATED STATEMENTS OF OPERATIONS

(unaudited, in thousands, except unit and per unit information)

	Three-month periods ended						Nine-month periods ended
	September 30,						September 30,
	2013			2012			2013			2012
Revenue:
Rents	$	116,479		$	108,658		$	347,680		$	327,362
Tenant reimbursements	20,699			20,294			60,615			57,179
Termination fees	2,040			931			2,946			2,522
Third party management fees, labor reimbursement and leasing	3,263			3,007			9,652			9,021
Other	975			1,630			3,305			4,029
Total revenue	143,456			134,520			424,198			400,113
Operating Expenses:
Property operating expenses	40,661			38,783			119,522			112,961
Real estate taxes	14,190			13,486			42,706			40,430
Third party management expenses	1,317			1,298			4,105			3,812
Depreciation and amortization	50,613			46,955			149,423			142,262
General & administrative expenses	6,436			6,080			20,322			18,209
Total operating expenses	113,217			106,602			336,078			317,674
Operating income	30,239			27,918			88,120			82,439
Other Income (Expense):
Interest income	268			311			448			2,631
Historic tax credit transaction income	11,853			11,840			11,853			11,840
Interest expense	(30,338		)	(32,620		)	(91,689		)	(99,745		)
Interest expense — amortization of deferred financing costs	(1,158		)	(1,218		)	(3,502		)	(3,790		)
Interest expense — financing obligation	(264		)	(230		)	(693		)	(608		)
Equity in income of real estate ventures	714			500			3,757			1,382
Gain from remeasurement of investment in a real estate venture	—			—			7,847			—
Net gain on real estate venture transactions	—			—			3,683			—
Net loss on sale of undepreciated real estate	(129		)	—			(129		)	—
Loss on real estate venture formation	—			(950		)	—			(950		)
Loss on early extinguishment of debt	(11		)	(51		)	(1,127		)	(1,549		)
Gain (Loss) from continuing operations	11,174			5,500			18,568			(8,350		)
Discontinued operations:
Income (Loss) from discontinued operations	(70		)	1,649			590			6,803
Net gain (loss) on disposition of discontinued operations	(16		)	9,940			3,029			34,774
Total discontinued operations	(86		)	11,589			3,619			41,577
Net income	11,088			17,089			22,187			33,227
Distribution to Preferred Units	(1,725		)	(2,785		)	(5,175		)	(7,832		)
Preferred unit redemption charge	—			—			—			(2,090		)
Amount allocated to unvested restricted unitholders	(85		)	(95		)	(278		)	(286		)
Net income attributable to Common Partnership Unitholders of Brandywine Operating Partnership, L.P.	$	9,278		$	14,209		$	16,734		$	23,019
Basic income (loss) per Common Partnership Unit:
Continuing operations	$	0.06		$	0.02		$	0.09		$	(0.13	)
Discontinued operations	—			0.08			0.02			0.29
	$	0.06		$	0.10		$	0.11		$	0.16
Diluted income (loss) per Common Partnership Unit:
Continuing operations	$	0.06		$	0.02		$	0.09		$	(0.13	)
Discontinued operations	—			0.08			0.02			0.29
	$	0.06		$	0.10		$	0.11		$	0.16
Basic weighted average common partnership units outstanding	158,467,087			146,082,206			153,731,070			145,842,872
Diluted weighted average common partnership units outstanding	159,755,821			146,785,731			154,940,454			145,842,872
Net income (loss) attributable to Brandywine Operating Partnership, L.P.
Income (Loss) from continuing operations	$	11,174		$	5,500		$	18,568		$	(8,350	)
Income (Loss) from discontinued operations	(86		)	11,589			3,619			41,577
Net income	$	11,088		$	17,089		$	22,187		$	33,227

The accompanying notes are an integral part of these consolidated financial statements.

15

BRANDYWINE OPERATING PARTNERSHIP, L.P.

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(unaudited, in thousands)

	Three-month periods ended						Nine-month periods ended
	September 30,						September 30,
	2013			2012			2013		2012
Net income	$	11,088		$	17,089		$	22,187	$	33,227
Comprehensive income (loss):
Unrealized gain (loss) on derivative financial instruments	(1,302		)	(4,222		)	9,978		(14,780		)
Reclassification of realized losses on derivative financial instruments to operations, net (1)	64			76			232		200
Unrealized gain on available-for-sale securities	—			65			—		—
Total comprehensive income (loss)	(1,238		)	(4,081		)	10,210		(14,580		)
Comprehensive income attributable to Brandywine Operating Partnership, L.P.	$	9,850		$	13,008		$	32,397	$	18,647

(1) Amounts reclassified from comprehensive income to interest expense within the Consolidated Statements of Operations.

The accompanying notes are an integral part of these consolidated financial statements.

16

BRANDYWINE OPERATING PARTNERSHIP L.P.

CONSOLIDATED STATEMENTS OF CASH FLOWS

(unaudited, in thousands)

	Nine-month periods ended
	September 30,
	2013			2012
Cash flows from operating activities:
Net income	$	22,187		$	33,227
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	151,066			150,362
Amortization of deferred financing costs	3,502			3,790
Amortization of debt discount/(premium), net	1,112			1,095
Amortization of stock compensation costs	5,510			3,740
Shares used for employee taxes upon vesting of share awards	(1,062		)	(2,232		)
Straight-line rent income	(16,337		)	(17,792		)
Amortization of acquired above (below) market leases, net	(5,372		)	(4,468		)
Straight-line ground rent expense	1,286			1,423
Provision for doubtful accounts	1,777			1,363
Net gain on sale of interests in real estate	(3,044		)	(34,773		)
Loss on real estate venture formation	—			950
Net gain on real estate venture transaction	(3,683		)	—
Gain on remeasurement of investment in a real estate venture	(7,847		)	—
Loss on early extinguishment of debt	1,127			1,549
Historic tax credit transaction income	(11,853		)	(11,840		)
Real estate venture income in excess of distributions	(2,371		)	(1,024		)
Deferred financing obligation	(1,392		)	(1,314		)
Changes in assets and liabilities:
Accounts receivable	(287		)	1,580
Other assets	(5,758		)	(7,200		)
Accounts payable and accrued expenses	14,684			9,565
Deferred income, gains and rent	1,265			(4,681		)
Other liabilities	1,718			(1,175		)
Net cash from operating activities	146,228			122,145
Cash flows from investing activities:
Acquisition of properties	(20,758		)	(9,226		)
Investments in available-for-sale securities	—			(98,250		)
Proceeds from sale of available-for-sale securities	—			98,250
Sales of properties, net	145,931			170,918
Distribution of sales proceeds from real estate ventures	16,963			—
Proceeds from repayment of mortgage notes receivable	200			23,930
Capital expenditures for tenant improvements	(64,481		)	(64,527		)
Capital expenditures for redevelopments	(5,288		)	(9,122		)
Capital expenditures for developments	(5,399		)	—
Reimbursement from real estate venture for pre-formation development costs	1,976			—
Advances for purchase of tenant assets, net of repayments	(420		)	(13		)
Investment in unconsolidated Real Estate Ventures	(30,142		)	(49,763		)
Cash distributions from unconsolidated Real Estate Ventures	3,661			2,779
Leasing costs	(25,704		)	(22,111		)
Net cash from investing activities	16,539			42,865
Cash flows from financing activities:
Proceeds from Unsecured Term Loans	—			600,000
Proceeds from Credit Facility borrowings	186,000			21,500
Repayments of Credit Facility borrowings	(255,000		)	(297,000		)
Repayments of mortgage notes payable	(8,351		)	(9,209		)
Deferred financing obligation non-cash interest expense	697			701
Net proceeds from issuance of common units	181,527			—
Net proceeds from issuance of preferred units	—			96,240
Redemption of preferred units	—			(50,188		)

17

Repayments of unsecured notes	(13,027		)	(167,841		)
Repayments of unsecured term loan	—			(37,500		)
Net settlement of hedge transactions	—			(74		)
Debt financing costs	(6		)	(8,462		)
Exercise of stock options	2,240			748
Distributions paid to preferred and common partnership unitholders	(72,879		)	(72,719		)
Net cash from financing activities	21,201			76,196
Increase in cash and cash equivalents	183,968			241,206
Cash and cash equivalents at beginning of period	1,549			410
Cash and cash equivalents at end of period	$	185,517		$	241,616
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the nine months ended September 30, 2013 and 2012 of $2,012 and $1,978, respectively	$	76,528		$	83,618
Supplemental disclosure of non-cash activity:
Change in operating real estate related to a non-cash acquisition of an operating property	(21,649		)	—
Change in intangible assets, net related to a non-cash acquisition of an operating property	(3,517		)	—
Change in acquired lease intangibles, net related to a non-cash acquisition of an operating property	462			—
Change in investments in joint venture related to non-cash acquisition of property	13,040			—
Change in operating real estate related to non-cash adjustment to land	(4,386		)	—
Change in investments in real estate ventures related to a contribution of land	(6,058		)	—
Change in capital expenditures financed through accounts payable at period end	1,210			(1,270		)
Change in capital expenditures financed through retention payable at period end	(736		)	284
Change in unfunded tenant allowance	(811		)	(1,411		)

The accompanying notes are an integral part of these consolidated financial statements.

18

BRANDYWINE REALTY TRUST AND BRANDYWINE OPERATING PARTNERSHIP, L.P.

NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS

SEPTEMBER 30, 2013

1. ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP

The Parent Company is a self-administered and self-managed real estate investment trust (“REIT”) that provides leasing, property management, development, redevelopment, acquisition and other tenant-related services for a portfolio of office and industrial properties. The Parent Company owns its assets and conducts its operations through the Operating Partnership and subsidiaries of the Operating Partnership. The Parent Company is the sole general partner of the Operating Partnership and, as of September 30, 2013, owned a 98.8% interest in the Operating Partnership. The Parent Company’s common shares of beneficial interest are publicly traded on the New York Stock Exchange under the ticker symbol “BDN”.

As of September 30, 2013, the Company owned 210 properties, consisting of 182 office properties (one of which is held-for-sale), 19 industrial facilities, five mixed-use properties, one development property, two redevelopment properties and one re-entitlement property (collectively, the “Properties”) containing an aggregate of approximately 24.1 million net rentable square feet. In addition, as of September 30, 2013, the Company owned economic interests in 18 unconsolidated real estate ventures that contain approximately 6.2 million net rentable square feet (collectively, the “Real Estate Ventures”). As of September 30, 2013, the Company also owned 423 acres of undeveloped land, and held options to purchase approximately 51 additional acres of undeveloped land. As of September 30, 2013, the total potential development that these land parcels could support, under current zoning, entitlements or combination thereof, amounted to 6.1 million square feet. The Properties and the properties owned by the Real Estate Ventures are located in or near Philadelphia, Pennsylvania; Metropolitan Washington, D.C.; Southern New Jersey; Richmond, Virginia; Wilmington, Delaware; Austin, Texas and Oakland, Concord, and Carlsbad, California.

The Company conducts its third-party real estate management services business primarily through wholly-owned management company subsidiaries. As of September 30, 2013, the management company subsidiaries were managing properties containing an aggregate of approximately 30.7 million net rentable square feet, of which approximately 24.1 million net rentable square feet related to Properties owned by the Company and approximately 6.6 million net rentable square feet related to properties owned by third parties and Real Estate Ventures.

2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, all adjustments (consisting solely of normal recurring matters) for a fair statement of the financial position of the Company as of September 30, 2013, the results of its operations for the three and nine-month periods ended September 30, 2013 and 2012 and its cash flows for the nine-month periods ended September 30, 2013 and 2012 have been included. The results of operations for such interim periods are not necessarily indicative of the results for a full year. These consolidated financial statements should be read in conjunction with the Parent Company’s and the Operating Partnership’s consolidated financial statements and footnotes included in their combined 2012 Annual Report on Form 10-K filed with the SEC on February 26, 2013.

Reclassifications

Certain amounts have been reclassified in prior years to conform to the current year presentation. The reclassifications are primarily due to the treatment of sold properties as discontinued operations on the statement of operations for all periods presented.

Principles of Consolidation

When the Company obtains an economic interest in an entity, the Company evaluates the entity to determine if the entity is deemed a variable interest entity (“VIE”), and if the Company is deemed to be the primary beneficiary, in accordance with the accounting standard for the consolidation of variable interest entities. The accounting standard for the consolidation of VIEs requires the Company to qualitatively assess if the Company was the primary beneficiary of the VIEs based on whether the Company had (i) the power to direct those matters that most significantly impacted the activities of the VIE and (ii) the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. For entities determined to be VIEs, but for which the Company is not the primary beneficiary, the Company's maximum exposure to loss is the carrying amount of its investments, as the Company has not provided any payment guarantees other than on approximately $0.6 million, as of September 30, 2013, of debt of the Real Estate Venture known as "PJP Building VII LC" and on the Company's share of the debt

19

and potential cost overruns associated with the Real Estate Venture known as "evo at Cira Centre South Venture" (formerly referred to as the "Grove Venture"). Please refer to Note 4.

When an entity is not deemed to be a VIE, the Company considers the provisions of the same accounting standard to determine whether a general partner, or the general partners as a group, controls a limited partnership or similar entity when the limited partners have certain rights. The Company consolidates (i) entities that are VIEs and of which the Company is deemed to be the primary beneficiary and (ii) entities that are non-VIEs and controlled by the Company and in which the limited partners neither have the ability to dissolve the entity or remove the Company without cause nor any substantive participating rights. Entities that the Company accounts for under the equity method (i.e., at cost, increased or decreased by the Company’s share of earnings or losses, plus contributions, less distributions) include (i) entities that are VIEs and of which the Company is not deemed to be the primary beneficiary, (ii) entities that are non-VIEs which the Company does not control, but over which the Company has the ability to exercise significant influence, and (iii) entities that are non-VIEs that the Company controls through its general partner status, but the limited partners in the entity have the substantive ability to dissolve the entity or remove the Company without cause or have substantive participating rights. The Company continuously assesses its determination of whether an entity is a VIE and who the primary beneficiary is, and whether or not the limited partners in an entity have substantive rights, more particularly if certain events occur that are likely to cause a change in the original determinations. The Company’s assessment includes a review of applicable documents such as, but not limited to, applicable partnership agreements, LLC and other real estate venture agreements and management and leasing agreements to determine whether the Company has control to direct the business activities of the entities. The portion of the consolidated entities that is not owned by the Company is presented as non-controlling interest as of and during the periods consolidated. All intercompany accounts and transactions have been eliminated in consolidation.

On July 31, 2013, the Company formed a Real Estate Venture known as "4040 Wilson LLC Venture" (and referred to as "4040 Wilson") with an unaffiliated third party. Based upon the facts and circumstances at formation of 4040 Wilson, the Company determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and the Company's lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by the Company, and is accounted for under the equity method of accounting. Please refer to Note 4.

On January 25, 2013, the Company formed the evo at Cira Centre South Venture (formerly referred to as the "Grove Venture"), a Real Estate Venture with two unaffiliated third parties. Based upon the facts and circumstances at formation of the evo at Cira Centre South Venture, the Company determined that the evo at Cira Centre South Venture is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate the evo at Cira Centre South Venture. Based upon each member's shared power over the evo at Cira Centre South Venture activities under the operating and related agreements of the evo at Cira Centre South Venture, and the Company's lack of exclusive control over the development and construction phases of the project, the evo at Cira Centre South Venture is not consolidated by the Company and is accounted for under the equity method of accounting. For further information regarding the evo at Cira Centre South Venture and its formation, please refer to Note 4.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Management makes significant estimates regarding revenue, valuation of real estate and related intangible assets and liabilities, impairment of long-lived assets, allowance for doubtful accounts and deferred costs.

Operating Properties

Operating properties are carried at historical cost less accumulated depreciation and impairment losses. The cost of operating properties reflects their purchase price or development cost. Acquisition costs related to business combinations are expensed as incurred. Costs incurred for the renovation and betterment of an operating property are capitalized to the Company’s investment in that property. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. Fully-depreciated assets are removed from the accounts.

20

Purchase Price Allocation

The Company allocates the purchase price of properties to net tangible and identified intangible assets acquired based on fair values. Above-market and below-market in-place lease values for acquired properties are recorded based on the present value (using an interest rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to the in-place leases and (ii) the Company’s estimate of the fair market lease rates for the corresponding in-place leases, measured over a period equal to the remaining non-cancelable term of the lease (including the below market fixed renewal period, if applicable). Capitalized above-market lease values are amortized as a reduction of rental income over the remaining non-cancelable terms of the respective leases. Capitalized below-market lease values are amortized as an increase to rental income over the remaining non-cancelable terms of the respective leases, including any below market fixed-rate renewal periods.

Other intangible assets also include amounts representing the value of tenant relationships and in-place leases based on the Company’s evaluation of the specific characteristics of each tenant’s lease and the Company’s overall relationship with the respective tenant. The Company generally estimates the cost to execute leases with terms similar to the remaining lease terms of the in-place leases, including leasing commissions, legal and other related expenses. This intangible asset is generally amortized to expense over the remaining term of the respective leases and any fixed-rate bargain renewal periods. Company estimates of value are made using methods similar to those used by independent appraisers or by using independent appraisals. Factors considered by the Company in this analysis include an estimate of the carrying costs during the expected lease-up periods considering current market conditions and costs to execute similar leases. In estimating carrying costs, the Company includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, which primarily range from three to twelve months. The Company also considers information obtained about each property as a result of its pre-acquisition due diligence, marketing and leasing activities in estimating the fair value of the tangible and intangible assets acquired. The Company also uses the information obtained as a result of its pre-acquisition due diligence as part of its consideration of the accounting standard governing asset retirement obligations, and, when necessary, will record a conditional asset retirement obligation as part of its purchase price.

Characteristics considered by the Company in allocating value to its tenant relationships include the nature and extent of the Company’s business relationship with the tenant, growth prospects for developing new business with the tenant, the tenant’s credit quality and expectations of lease renewals, among other factors. The value of tenant relationship intangibles is generally amortized over the remaining initial lease term and expected renewals, but in no event longer than the remaining depreciable life of the building. The value of in-place leases is generally amortized over the remaining non-cancelable term of the respective leases and any fixed-rate renewal periods.

In the event that a tenant terminates its lease, the unamortized portion of each intangible, including in-place lease values and tenant relationship values, would be charged to expense and market rate adjustments (above or below) would be recorded to revenue.

Impairment or Disposal of Long-Lived Assets

The accounting standard for property, plant and equipment provides a single accounting model for long-lived assets classified as held-for-sale; defines the scope of businesses to be disposed of that qualify for reporting as discontinued operations; and affects the timing of recognizing losses on such operations.

The Company reviews long-lived assets whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The review of recoverability is based on an estimate of the future undiscounted cash flows (excluding interest charges) expected to result from the long-lived asset’s use and eventual disposition. These cash flows consider factors such as expected future operating income, trends and prospects, as well as the effects of leasing demand, competition and other factors. If impairment exists due to the inability to recover the carrying value of a long-lived asset, an impairment loss is recorded to the extent that the carrying value exceeds the estimated fair-value of the property. The Company is required to make subjective assessments as to whether there are impairments in the values of the investments in long-lived assets. These assessments have a direct impact on its net income because recording an impairment loss results in an immediate negative adjustment to net income. The evaluation of anticipated cash flows is highly subjective and is based in part on assumptions regarding future occupancy, rental rates and capital requirements that could differ materially from actual results in future periods. Although the Company’s strategy is generally to hold its properties over the long-term, the Company will selectively dispose of properties for strategic needs. If the Company’s strategy changes or market conditions otherwise dictate an earlier sale date, an impairment loss may be recognized to reduce the property to the lower of the carrying amount or fair value less costs to sell, and such loss could be material. If the Company determines that impairment has occurred and the assets are classified as held and used, the affected assets must be reduced to their fair-value.

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Where properties have been identified as having a potential for sale, additional judgments are required related to the determination as to the appropriate period over which the undiscounted cash flows should include the operating cash flows and the amount included as the estimated residual value. Management determines the amounts to be included based on a probability weighted cash flow. This requires significant judgment. In some cases, the results of whether an impairment is indicated are sensitive to changes in assumptions input into the estimates, including the hold period until expected sale.

The Company determined during its impairment review for the three and nine-month periods ended September 30, 2013 and 2012, that no impairment charges were necessary.

Investments in Unconsolidated Real Estate Ventures

The Company accounts for its investments in unconsolidated Real Estate Ventures under the equity method of accounting as it is not the primary beneficiary (for VIEs) and the Company exercises significant influence, but does not control these entities under the provisions of the entities’ governing agreements pursuant to the accounting standard for the consolidation of VIEs. When the Company determines that its investment in an unconsolidated Real Estate Venture does not constitute a VIE, the Company utilizes the voting interest model under the accounting standard for consolidation to determine whether to consolidate the venture.

Under the equity method, investments in unconsolidated Real Estate Ventures are recorded initially at cost, as investments in Real Estate Ventures, and subsequently adjusted for equity in earnings, cash contributions, less distributions and impairments. On a periodic basis, management also assesses whether there are any indicators that the value of the Company’s investments in unconsolidated Real Estate Ventures may be other than temporarily impaired. An investment is impaired only if the value of the investment, as estimated by management, is less than the carrying value of the investment and the decline is other than temporary. To the extent that an impairment has occurred, the loss shall be measured as the excess of the carrying amount of the investment over the fair value of the investment, as estimated by management. The determination as to whether an impairment exists requires significant management judgment about the fair value of its ownership interest. Fair value is determined through various valuation techniques, including but not limited to, discounted cash flow models, quoted market values and third party appraisals.

When the Company acquires an interest in or contributes assets to a Real Estate Venture project, the difference between the Company’s cost basis in the investment and the value of the Real Estate Venture or asset contributed is amortized over the life of the related assets, intangibles and liabilities and such adjustment is included in the Company’s share of equity in income of unconsolidated Real Estate Ventures. For purposes of cash flow presentation, distributions from unconsolidated Real Estate Ventures are presented as part of operating activities when they are considered as return on investments. Distributions in excess of the Company’s share in the cumulative unconsolidated Real Estate Ventures’ earnings are considered as return of investments and are presented as part of investing activities in accordance with the accounting standard for cash flow presentation.

Revenue Recognition

Rental revenue is recognized on the straight-line basis, which averages minimum rents over the terms of the leases from the later of the date of the commencement of the lease or the date of acquisition of the property subject to existing leases. The straight-line rent adjustment increased revenue by approximately $4.5 million and $14.5 million for the three and nine-month periods ended September 30, 2013, and approximately $4.3 million and $16.0 million for the three and nine-month periods ended September 30, 2012, respectively. Deferred rents on the balance sheet represent rental revenue received prior to their due dates and amounts paid by the tenant for certain improvements considered to be landlord assets that will remain as the Company’s property at the end of the tenant’s lease term. The amortization of the amounts paid by the tenant for such improvements is calculated on a straight-line basis over the term of the tenant’s lease and is a component of straight-line rental income and increased revenue by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2013, and by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2012, respectively. Lease incentives, which are included as reductions of rental revenue in the accompanying consolidated statements of operations, are recognized on a straight-line basis over the term of the lease. Lease incentives decreased revenue by $0.2 million and $0.4 million for the three and nine-month periods ended September 30, 2013, and decreased revenue by $0.1 million and $0.6 million for the three and nine-month periods ended September 30, 2012, respectively.

Leases also typically provide for tenant reimbursement of a portion of common area maintenance and other operating expenses to the extent that a tenant’s pro rata share of expenses exceeds a base year level set in the lease or to the extent that the tenant has a lease on a triple net basis. For certain leases, significant assumptions and judgments are made by the Company in determining the lease term such as when termination options are provided to the tenant. The lease term impacts the period over which minimum rents are determined and recorded and also considers the period over which lease related costs are amortized. Termination fees received from tenants, bankruptcy settlement fees, third party management fees, labor reimbursement and leasing income are recorded when earned.

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Stock-Based Compensation Plans

The Parent Company maintains a shareholder-approved equity-incentive plan known as the Amended and Restated 1997 Long-Term Incentive Plan (the “1997 Plan”). The 1997 Plan is administered by the Compensation Committee of the Parent Company’s Board of Trustees. Under the 1997 Plan, the Compensation Committee is authorized to award equity and equity-based awards, including incentive stock options, non-qualified stock options, restricted shares and performance-based shares. As of September 30, 2013, 5,195,177 common shares remained available for future awards under the 1997 Plan (including 3,011,946 shares available solely for options and share appreciation rights). Through September 30, 2013, all options awarded under the 1997 Plan had a one to ten-year term.

The Company incurred stock-based compensation expense of $2.3 million and $7.0 million during the three and nine-month periods ended September 30, 2013, of which $0.3 million and $1.1 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The Company incurred stock-based compensation expense of $1.8 million and $5.5 million during the three and nine-month periods ended September 30, 2012, of which $0.5 million and $1.4 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The expensed amounts are included in general and administrative expense on the Company’s consolidated income statement in the respective periods.

Accounting for Derivative Instruments and Hedging Activities

The Company accounts for its derivative instruments and hedging activities in accordance with the accounting standard for derivative and hedging activities. The accounting standard requires the Company to measure every derivative instrument (including certain derivative instruments embedded in other contracts) at fair value and record them in the balance sheet as either an asset or liability. See disclosures below related to the accounting standard for fair value measurements and disclosures.

For derivatives designated as cash flow hedges, the effective portions of changes in the fair value of the derivative are reported in other comprehensive income while the ineffective portions are recognized in earnings.

The Company actively manages its ratio of fixed-to-floating rate debt. To manage its fixed and floating rate debt in a cost-effective manner, the Company, from time to time, enters into interest rate swap agreements as cash flow hedges, under which it agrees to exchange various combinations of fixed and/or variable interest rates based on agreed upon notional amounts.

Fair Value Measurements

The Company estimates the fair value of its derivatives and available-for-sale securities in accordance with the accounting standard for fair value measurements and disclosures. The accounting standard defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. It also establishes a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value. Financial assets and liabilities recorded on the Consolidated Balance Sheets are categorized based on the inputs to the valuation techniques as follows:

• Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access;

• Level 2 inputs are inputs other than quoted prices included in Level 1, that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals; and

• Level 3 inputs are unobservable inputs for the asset or liability, which is typically based on an entity’s own assumptions, as there is little, if any, related market activity or information.

In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

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The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2013		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	112	$	—	$	112	$	—
Liabilities:
Interest Rate Swaps	$	4,314	$	—	$	4,314	$	—

The following table sets forth the Company’s financial liabilities that were accounted for at fair value on a recurring basis as of December 31, 2012 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2012		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	—	$	—	$	—	$	—
Liabilities:
Interest Rate Swaps	$	14,210	$	—	$	14,210	$	—

We classify our interest rate swaps, shown above, within Level 2 as the valuation inputs are based on quoted prices and market observable data of similar instruments.

Non-financial assets and liabilities recorded at fair value on a non-recurring basis to which the Company would apply the accounting standard where a measurement was required under fair value would include:

• Non-financial assets and liabilities initially measured at fair value in an acquisition or business combination that are not remeasured at least quarterly at fair value,

• Long-lived assets measured at fair value due to an impairment in accordance with the accounting standard for the impairment or disposal of long-lived assets,

• Equity and cost method investments measured at fair value due to an impairment in accordance with the accounting standard for investments,

• Notes receivable adjusted for any impairment in its value in accordance with the accounting standard for loan receivables, and

• Asset retirement obligations initially measured at fair value under the accounting standard for asset retirement obligations.

Other than the remeasurement of Six Tower Bridge (see Note 3), there were no items that were accounted for at fair value on a non-recurring basis for the nine months ended September 30, 2013.

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Notes Receivable

As of September 30, 2013 and December 31, 2012, notes receivable included a purchase money mortgage with a 20-year amortization period bearing interest at 8.5%, which was valued at $7.0 million and $7.2 million, respectively. The borrower had previously defaulted on the note. As a result, a forbearance agreement dated October 2011, as amended by a second forbearance agreement dated July 9, 2013, was entered into between the Company and the borrower, outlining the repayment terms of the outstanding debt. The Company has determined that the loan modification represents a troubled debt restructuring due to the fact that the borrower was considered to be in a financial difficulty when it defaulted on the two mortgage debts, and that a concession was granted in the form of the forbearance agreements. In accordance with the accounting standard for loan receivables the Company performs, on an ongoing basis, a collectability assessment of the note using the expected cash flow information provided by the borrower. Based on cash flow projections provided by the borrower, the note will be fully paid during 2015. As of September 30, 2013, the present value of the expected cash flows of the note receivable exceeded the outstanding balance of the note and therefore the note is recoverable as of September 30, 2013.

Income Taxes

Parent Company

The Parent Company has elected to be treated as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). In order to continue to qualify as a REIT, the Parent Company is required to, among other things, distribute at least 90% of its annual REIT taxable income to its shareholders and meet certain tests regarding the nature of its income and assets. As a REIT, the Parent Company is not subject to federal and state income taxes with respect to the portion of its income that meets certain criteria and is distributed annually to its shareholders. Accordingly, no provision for federal and state income taxes is included in the accompanying consolidated financial statements with respect to the operations of the Parent Company. The Parent Company intends to continue to operate in a manner that allows it to meet the requirements for taxation as a REIT. If the Parent Company fails to qualify as a REIT in any taxable year, it will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent tax years. The Parent Company is subject to certain local income taxes. Provision for such taxes has been included in general and administrative expenses in the Parent Company’s Consolidated Statements of Operations and Comprehensive Income.

The Parent Company has elected to treat several of its subsidiaries as taxable REIT subsidiaries (each a “TRS”). A TRS is subject to federal, state and local income tax. In general, a TRS may perform non-customary services for tenants, hold assets that the Parent Company, as a REIT, cannot hold directly and generally may engage in any real estate or non-real estate related business.

Operating Partnership

In general, the Operating Partnership is not subject to federal and state income taxes, and accordingly, no provision for income taxes has been made in the accompanying consolidated financial statements. The partners of the Operating Partnership are required to include their respective share of the Operating Partnership’s profits or losses in their respective tax returns. The Operating Partnership’s tax returns and the amount of allocable Partnership profits and losses are subject to examination by federal and state taxing authorities. If such examination results in changes to the Operating Partnership profits or losses, then the tax liability of the partners would be changed accordingly.

The Operating Partnership may elect to treat one or more of its subsidiaries as REITs under Sections 856 through 860 of the Code. Each subsidiary REIT has met the requirements for treatment as a REIT under Sections 856 through 860 of the Code, and, accordingly, no provision has been made for federal and state income taxes in the accompanying consolidated financial statements. If any subsidiary REIT fails to qualify as a REIT in any taxable year, that subsidiary REIT will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent taxable years. Also, each subsidiary REIT may be subject to certain local income taxes.

The Operating Partnership has elected to treat several of its subsidiaries as taxable TRSs, which are subject to federal, state and local income tax.

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Recent Accounting Pronouncements

In February 2013, the Financial Accounting Standards Board (FASB) issued an amendment to the accounting standard for the presentation of comprehensive income. This amendment requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component, and represents the culmination of the FASB's redeliberation on the reporting of such reclassification adjustments. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income, but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. This update is effective for fiscal years and interim periods beginning after December 15, 2012. The Company’s adoption of the accounting standard did not have a material impact on its consolidated financial position or results of operations as the update relates only to changes in financial statement presentation.

3. REAL ESTATE INVESTMENTS

As of September 30, 2013 and December 31, 2012, the gross carrying value of the Company’s Properties was as follows (in thousands):

	September 30, 2013		December 31, 2012
Land	$	664,952	$	662,107
Building and improvements	3,465,544		3,576,065
Tenant improvements	501,414		487,997
	$	4,631,910	$	4,726,169

Acquisitions

On June 19, 2013, the Company acquired the remaining ownership interest in the Real Estate Venture known as "Six Tower Bridge" that it did not then already own. See Note 4 "Investments in Unconsolidated Real Estate Ventures" for further discussion.

On April 25, 2013, the Company exercised its purchase option under the long term ground lease agreement it held through its acquisition of Three Logan Square on August 5, 2010 and acquired the 1.8 acre land parcel underlying Three Logan Square in Philadelphia, Pennsylvania for $20.8 million. The Company has accounted for the transaction as an asset acquisition. A portion of the original purchase price of Three Logan Square was allocated to the below market ground lease intangible asset, as the sum of the purchase price of the land plus the $4.3 million remaining unamortized balance for the intangible asset approximates the fair value of the land as unencumbered by the ground lease. The remaining intangible asset balance was reclassified to land upon exercise of the purchase option. The Company funded the cost of the acquisition with available corporate funds and capitalized $0.1 million of acquisition related costs as part of the basis in the operating land.

Dispositions

On August 5, 2013, the Company sold an eight-acre parcel of land located in Richmond, Virginia known as Dabney Land East, for a sales price of $0.5 million. The land parcel was undeveloped as of the date of sale.

On June 28, 2013, the Company sold 16870 West Bernardo Drive, a 67,909 net rentable square feet office property located in San Diego, California, for a sales price of $18.0 million. The property was 98.8% occupied as of the date of sale.

On June 28, 2013, the Company sold 100 Arrandale Boulevard, a 34,931 net rentable square feet office property located in Exton, Pennsylvania, for a sales price of $3.5 million. The property was vacant at the date of sale.

On June 19, 2013, the Company sold 1700 Paoli Pike, a 28,000 net rentable square feet office property located in Malvern, Pennsylvania, for a sales price of $2.7 million. The property was vacant at the date of sale.

On June 14, 2013, the Company sold Pacific View Plaza, a 51,695 net rentable square feet office property located in Carlsbad, California, for a sales price of $10.3 million. The property was 90.5% occupied as of the date of sale.

On February 25, 2013, the Company sold a portfolio of eight office properties containing 800,546 square feet in Lawrenceville, New Jersey for an aggregate sales price of $121.0 million. These properties, collectively known as "Princeton Pike Corporate Center," were 86.9% occupied as of the date of sale.

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The sales of these properties are included in discontinued operations (see Note 10).

4. INVESTMENT IN UNCONSOLIDATED VENTURES

As of September 30, 2013, the Company had an aggregate investment of approximately $194.6 million in 18 unconsolidated Real Estate Ventures. The Company formed or acquired interests in these ventures with unaffiliated third parties to develop or manage office properties or to acquire land in anticipation of possible development of office or residential properties. As of September 30, 2013, 12 of the Real Estate Ventures owned 50 office buildings that contain an aggregate of approximately 6.2 million net rentable square feet; four Real Estate Ventures owned 25.3 acres of undeveloped parcels of land; one Real Estate Venture owned 1.0-acres of land under active development and one Real Estate Venture developed a hotel property that contains 137 rooms in Conshohocken, PA.

The Company accounts for its unconsolidated interests in its Real Estate Ventures using the equity method. The Company’s unconsolidated interests range from 20% to 65%, subject to specified priority allocations of distributable cash in certain of the Real Estate Ventures.

The amounts reflected in the following tables (except for the Company’s share of equity and income) are based on the historical financial information of the individual Real Estate Ventures. The Company does not record operating losses of the Real Estate Ventures in excess of its investment balance unless the Company is liable for the obligations of the Real Estate Venture or is otherwise committed to provide financial support to the Real Estate Venture.

The following is a summary of the financial position of the Real Estate Ventures as of September 30, 2013 and December 31, 2012 (in thousands):

	September 30, 2013		December 31, 2012
Net property	$	879,838	$	923,536
Other assets	164,508		174,677
Other liabilities	36,115		53,645
Debt	707,847		724,780
Equity	300,384		319,788
Company’s share of equity (Company’s basis) (a)	194,572		193,555

(a) Amounts reflect the effects of basis differences resulting from assets contributed to Real Estate Ventures, as well as certain costs at the Real Estate Venture level. Basis differences occur from the impairment of investments and upon the transfer of assets that were previously owned by the Company into a Real Estate Venture. In addition, certain acquisition, transaction and other costs may not be reflected in the net assets at the Real Estate Venture level.

The following is a summary of results of operations of the Real Estate Ventures for the three and nine-month periods ended September 30, 2013 and 2012 (in thousands):

	Three-month periods ended September 30,					Nine-month periods ended September 30,
	2013			2012		2013			2012
Revenue	$	30,684		$	42,772	$	108,500		$	120,644
Operating expenses	13,199			18,753		48,671			51,819
Interest expense, net	9,223			10,233		28,167			31,100
Depreciation and amortization	9,893			12,947		33,778			36,067
Net income (loss)	(1,631		)	839		(2,116		)	1,658
Company’s share of income (Company’s basis)	714			500		3,757			1,382

4040 Wilson Venture

On July 31, 2013, the Company formed 4040 Wilson LLC Venture ("4040 Wilson"), a joint venture between the Company and Ashton Park Associates LLC (“Ashton Park”), an unaffiliated third party. 4040 Wilson expects to construct a 20-story office building located in the Ballston submarket of Arlington, Virginia. Each of the Company and Ashton Park owns a 50% interest in 4040 Wilson. 4040 Wilson would develop the project on a 1.3-acre land parcel contributed by Ashton Park at an agreed upon value of $36.0 million. The total estimated project costs are $194.3 million, which the Company expects would be financed through approximately $72.0 million of partner capital contributions (consisting of $36.0 million in cash from the Company and land with a value of $36.0 million from Ashton Park) and approximately $122.3 million of debt financing through a construction lender that

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has not yet been determined. Construction is scheduled to commence during the fourth quarter of 2013, with a targeted project completion in 2015. As part of the 4040 Wilson venture, the Company has agreed to guarantee 100% of any lender mandated recourse. As of September 30, 2013, the Company had not provided any guarantees in respect of 4040 Wilson.

Based upon the facts and circumstances at formation of 4040 Wilson, the Company determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and the Company's lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by the Company, and is accounted for under the equity method of accounting.

Two and Six Tower Bridge Exchange Transaction

On June 19, 2013, the Company acquired, from an unaffiliated third party, the third party's ownership interest in Six Tower Bridge real estate venture through a nonmonetary exchange for the Company's ownership interest in the Two Tower Bridge real estate venture. Six Tower Bridge owns an unencumbered office property in Conshohocken, PA. The Company previously accounted for its noncontrolling interest in Six Tower Bridge using the equity method. As a result of the exchange transaction, the Company obtained control of the Six Tower Bridge property and the Company's existing equity interest was remeasured at fair value based on the fair value of the underlying property and the distribution provisions of the real estate venture agreement. Accordingly, during 2013, the Company recorded a gain of approximately $7.8 million, which is reflected in "Gain from remeasurement of investment in a real estate venture" on the accompanying statements of operations. Following the acquisition, the Class A office property in Conshohocken, PA is wholly owned by the Company with an unencumbered fair value of $24.5 million. The Company accounted for this acquisition as a business combination and allocated the fair value as follows: $14.8 million to building, $6.9 million to land, $3.3 million to intangible assets and $0.5 million to below market lease liabilities assumed.

As mentioned above, the Company exchanged its investment in Two Tower Bridge real estate venture in a nonmonetary transaction with an unaffiliated third party for the third party's interest in the Six Tower Bridge real estate venture. The investment in Two Tower Bridge had a fair value of $3.6 million on the date of the exchange transaction based on the fair value of the venture's equity and the distribution provisions of the real estate venture agreement. Based on this fair value and the carrying value for the Company's investment of $(0.1) million, during 2013 the Company recognized a gain on exchange ofinterests in real estate venturesof $3.7 million.

evo at Cira Centre South Venture (formerly the Grove Venture)

On January 25, 2013, the Company formed the evo at Cira Centre South Venture, a joint venture among the Company and two unaffiliated third parties: Campus Crest Properties, LLC ("Campus Crest") and HSRE-Campus Crest IXA, LLC ("HSRE"). The evo at Cira Centre South Venture has commenced construction of a 33-story, 850-bed student housing tower located in the University City submarket of Philadelphia, Pennsylvania, to be called "evo at Cira Centre South." Each of the Company and Campus Crest owns a 30% interest in the evo at Cira Centre South Venture and HSRE owns a 40% interest. The evo at Cira Centre South Venture is developing the project on a one-acre land parcel held under a long-term ground lease with a third party lessor. The Company contributed to the evo at Cira Centre South Venture its tenancy rights under a long-term ground lease, together with associated development rights, at an agreed-upon value of $8.5 million. The total estimated project costs are $158.5 million, which will be financed through partner capital contributions totaling $60.7 million, with the remaining $97.8 million being financed through construction facilities provided by PNC Bank, Capital One and First Niagara Bank. Construction has already commenced, with a targeted project completion in 2014. In connection with the development of the evo at Cira Centre South Venture, each of the Company and Campus Crest provided, in addition to customary non-recourse carve-out guarantees, a completion and cost overrun guaranty, as well as a payment guaranty, on the construction financing (with the Company's share of the payment guaranty being approximately $23.0 million).

The Company's historical cost basis in the development rights that it contributed to the evo at Cira Centre South Venture at formation was $6.0 million, thus creating an initial $2.5 million basis difference between the Company's initial outside investment basis compared to its $8.5 million initial equity basis in the evo at Cira Centre South Venture. As this basis difference is not related to a physical land parcel, but rather to development rights to construct evo at Cira Centre South, the Company will accrete the basis difference as a reduction of depreciation expense over the life of the evo at Cira Centre South Venture's assets.

Based upon the facts and circumstances at evo at Cira Centre South Venture Venture formation, the Company determined that the evo at Cira Centre South Venture is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate the evo at Cira Centre South Venture. Based upon each member's shared power over the activities of the evo at Cira Centre South Venture under the operating and related agreements of the evo at Cira Centre South Venture, and the Company's lack

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of exclusive control over the development and construction phases of the project, the evo at Cira Centre South Venture is not consolidated by the Company, and is accounted for under the equity method of accounting. Accordingly, the land parcel and associated development rights contributed by the Company to the evo at Cira Centre South Venture were deconsolidated by the Company upon formation of the evo at Cira Centre South Venture.

BDN Beacon Venture

On March 26, 2013, the Company sold its entire 20% ownership interest in an unconsolidated real estate venture known as BDN Beacon Venture LLC (the "Beacon Venture"). The carrying amount of the Company's investment in the Beacon Venture amounted to $17.0 million at the sale date, with the Company's proceeds effectively matching the carrying amount.

The Company, from time to time, also provides guarantees and indemnities on behalf of Real Estate Ventures, including environmental indemnities and non-recourse carve-outs under mortgage loans, in connection with both construction and permanent financing. As of September 30, 2013, the Company had guaranteed repayment of approximately $0.6 million of loans on behalf of the PJP VII Real Estate Venture.

5. DEFERRED COSTS

As of September 30, 2013 and December 31, 2012, the Company’s deferred costs were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	159,113	$	(59,569	)	$	99,544
Financing Costs	40,116		(13,400		)	26,716
Total	$	199,229	$	(72,969	)	$	126,260

	December 31, 2012
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	150,331	$	(58,343	)	$	91,988
Financing Costs	40,246		(9,991		)	30,255
Total	$	190,577	$	(68,334	)	$	122,243

During the three and nine-month periods ended September 30, 2013, the Company capitalized internal direct leasing costs of $1.4 million and $4.3 million, respectively, and $1.3 million and $4.0 million during the three and nine-month periods ended September 30, 2012, respectively, in accordance with the accounting standard for the capitalization of leasing costs.

6. INTANGIBLE ASSETS AND LIABILITIES

As of September 30, 2013 and December 31, 2012, the Company’s intangible assets/liabilities were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	81,410	$	(42,629	)	$	38,781
Tenant relationship value	46,160		(31,786		)	14,374
Above market leases acquired	2,705		(1,403		)	1,302
Total	$	130,275	$	(75,818	)	$	54,457
Below market leases acquired	$	76,874	$	(48,374	)	$	28,500

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	December 31, 2012
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	87,909	$	(42,894	)	$	45,015
Tenant relationship value	56,137		(37,389		)	18,748
Above market leases acquired	8,565		(1,708		)	6,857
Total	$	152,611	$	(81,991	)	$	70,620
Below market leases acquired	$	77,083	$	(43,224	)	$	33,859

As of September 30, 2013, the Company’s annual amortization for its intangible assets/liabilities were as follows (in thousands, and assuming no early lease terminations):

	Assets		Liabilities
2013 (three months remaining)	$	3,787	$	1,915
2014	13,335		6,179
2015	10,661		4,014
2016	6,285		2,074
2017	5,117		1,545
Thereafter	15,272		12,773
Total	$	54,457	$	28,500

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7. DEBT OBLIGATIONS

The following table sets forth information regarding the Company’s consolidated debt obligations outstanding at September 30, 2013 and December 31, 2012 (in thousands):

Property / Location	September 30, 2013			December 31, 2012			Effective Interest Rate			Maturity Date
MORTGAGE DEBT:
Tysons Corner	$	91,855		$	93,188		5.36	%	(a)	Aug-15
Two Logan Square	88,782			89,340			7.57	%		Apr-16
Fairview Eleven Tower	21,754			22,000			4.25	%		Jan-17
IRS Philadelphia Campus	192,535			197,111			7.00	%		Sep-30
Cira South Garage	40,664			42,303			7.12	%		Sep-30
Principal balance outstanding	435,590			443,942
Plus: fair market value premiums (discounts), net	(695		)	(968		)
Total mortgage indebtedness	$	434,895		$	442,974
UNSECURED DEBT:
Credit Facility	—			69,000			LIBOR + 1.50%			Feb-16
Three-Year Term Loan - Swapped to fixed	150,000			150,000			2.60	%		Feb-15
Four-Year Term Loan - Variable	100,000			100,000			LIBOR + 1.75%			Feb-16
Seven-Year Term Loan - Swapped to fixed	200,000			200,000			3.62	%		Feb-19
$250.0M 5.400% Guaranteed Notes due 2014	232,199			238,379			5.53	%		Nov-14
$250.0M 7.500% Guaranteed Notes due 2015	161,325			166,535			7.76	%		May-15
$250.0M 6.000% Guaranteed Notes due 2016	149,919			150,429			5.95	%		Apr-16
$300.0M 5.700% Guaranteed Notes due 2017	300,000			300,000			5.68	%		May-17
$325.0M 4.950% Guaranteed Notes due 2018	325,000			325,000			5.13	%		Apr-18
$250.0M 3.950% Guaranteed Notes due 2023	250,000			250,000			4.02	%		Feb-23
Indenture IA (Preferred Trust I)	27,062			27,062			2.75	%		Mar-35
Indenture IB (Preferred Trust I)	25,774			25,774			3.30	%		Apr-35
Indenture II (Preferred Trust II)	25,774			25,774			3.09	%		Jul-35
Principal balance outstanding	1,947,053			2,027,953
Plus: original issue premiums (discounts), net	(4,757		)	(5,597		)
Total unsecured indebtedness	$	1,942,296		$	2,022,356
Total Debt Obligations	$	2,377,191		$	2,465,330

(a) This loan was assumed upon acquisition of the property that secures the mortgage debt. The interest rate reflects the market rate at the time of acquisition.

During the nine-month periods ended September 30, 2013 and September 30, 2012, the Company’s weighted-average effective interest rate on its mortgage notes payable was 6.64% and 6.72%, respectively.

During the nine months ended September 30, 2013, the Company repurchased $11.9 million in principal amount of its outstanding unsecured notes in a series of transactions that are summarized in the following table (in thousands):

Notes	Repurchase Amount		Principal		Loss			Deferred Financing Amortization
2014 5.400% Notes	$	6,570	$	6,180	$	(401	)	$	7
2015 7.500% Notes	5,843		5,210		(663		)	15
2016 6.000% Notes	573		510		(63		)	1
	$	12,986	$	11,900	$	(1,127	)	$	23

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The Parent Company unconditionally guarantees the unsecured debt obligations of the Operating Partnership (or is a co-borrower with the Operating Partnership) but does not by itself incur unsecured indebtedness. The Parent Company has no material assets other than its investment in the Operating Partnership.

The Company utilizes its unsecured revolving credit facility (the "Credit Facility") for general business purposes, including to fund costs of acquisitions, developments and redevelopments and repayment of other debt. The scheduled maturity date of the Credit Facility in place at September 30, 2013 is February 1, 2016. The per annum variable interest rate on balances outstanding under the Credit Facility is LIBOR plus 1.50%. The interest rate and facility fee are subject to adjustment upon a change in the Company’s unsecured debt ratings. As of September 30, 2013, the Company did not have any outstanding borrowings on its Credit Facility, with $1.3 million in letters of credit outstanding, leaving $598.7 million of unused availability under the Credit Facility. During each of the three and nine-month periods ended September 30, 2013 and 2012, there were no weighted-average interest rates associated with the Credit Facility because there were no borrowings outstanding under the Credit Facility during either period.

The Company has the option to increase the amounts available to be advanced under the Credit Facility, the $150.0 million three-year term loan, and the $100.0 million four-year term loan by an aggregate of $200.0 million, subject to customary conditions and limitations, by obtaining additional commitments from the current lenders and other financial institutions. The Company also has the option to extend the maturity dates of each of the Credit facility, the $150.0 million three-year term loan and the $100.0 million four-year term loan by one year, subject to payment of an extension fee and other customary conditions and limitations. The Company may repay the $150.0 million three-year term loan and the $100.0 million four-year term loan at any time without penalty. The $200.0 million seven-year term loan is subject to a declining prepayment penalty (3.00% commencing one year after closing, 2.00% after two years, 1.00% after three years and without penalty thereafter).

The spread to LIBOR for LIBOR-based loans under the Credit Facility and term loans depends on the Company's unsecured senior debt credit rating. Based on the Company's current credit rating, the spread for such loans will be 150 basis points under the Credit Facility, 175 basis points under both the $150.0 million three-year term loan and the $100.0 million four-year term loan and 190 basis points under the $200.0 million seven-year term loan. At the Company's option, advances under the Credit Facility and term loans may also bear interest at a per annum floating rate equal to the higher of the prime rate or the federal funds rate plus 0.50% per annum. The Credit Facility contains a competitive bid option that allows banks that are part of the lender consortium to bid to make loans to the Company at a reduced rate. The Company executed hedging transactions that fix the rate on the $200.0 million seven-year term loan at a 3.623% average rate for its full term, and the rate on the $150.0 million three-year term loan at a 2.596% average rate for periods of three to four years. All hedges commenced on February 1, 2012 and the rates are inclusive of the LIBOR spread based on the Company's current investment grade rating. See Note 9 for details of the interest rate swaps entered into as of September 30, 2013.

The Credit Facility and term loans contain financial and operating covenants and restrictions. The Company was in compliance with all such restrictions and financial covenants as of September 30, 2013.

As of September 30, 2013, the Company’s aggregate scheduled principal payments on debt obligations, excluding amortization of discounts and premiums, were as follows (in thousands):

2013 (three months remaining)	$	2,886
2014	244,141
2015	411,358
2016	346,528
2017	330,323
Thereafter	1,047,407
Total principal payments	2,382,643
Net unamortized premiums/(discounts)	(5,452		)
Outstanding indebtedness	$	2,377,191

8. FAIR VALUE OF FINANCIAL INSTRUMENTS

The Company determined the fair values disclosed below using available market information and discounted cash flow analyses as of September 30, 2013 and December 31, 2012, respectively. The discount rate used in calculating fair value is the sum of the current risk free rate and the risk premium on the date of measurement of the instruments or obligations. Considerable judgment is necessary to interpret market data and to develop the related estimates of fair value. Accordingly, the estimates presented are not necessarily indicative of the amounts that the Company could realize upon disposition. The use of different estimates and

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valuation methodologies may have a material effect on the fair value amounts shown. The Company believes that the carrying amounts reflected in the consolidated balance sheets at September 30, 2013 and December 31, 2012 approximate the fair values for cash and cash equivalents, accounts receivable, other assets, accounts payable and accrued expenses.

The following are financial instruments for which the Company’s estimates of fair value differ from the carrying amounts (in thousands):

	September 30, 2013				December 31, 2012
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Mortgage notes payable	$	435,590	$	473,614	$	443,942	$	486,412
Unsecured notes payable	$	1,418,443	$	1,499,166	$	1,430,343	$	1,553,123
Variable rate debt	$	528,610	$	526,693	$	597,610	$	595,693
Notes receivable	$	7,026	$	7,491	$	7,226	$	7,783

The fair value of the Company's unsecured notes payable is categorized at a Level 2 basis (as provided by the accounting standard for Fair Value Measurements and Disclosures). This is because the Company valued these instruments using quoted market prices as of September 30, 2013 and December 31, 2012.

The fair value of the Company's mortgage notes payable, variable rate debt and notes receivable are all categorized at a Level 3 basis (as provided by the accounting standard for Fair Value Measurements and Disclosures). The fair value of the variable rate debt was estimated using a discounted cash flow analysis valuation on the borrowing rates currently available to the Company for loans with similar terms and maturities, as applicable. The fair value of the mortgage debt was determined by discounting the future contractual interest and principal payments by a blended market rate. The fair value of the notes receivable was determined by using the expected cash flows of the notes receivable, and discounting those cash flows using the market rate of interest for mortgage notes with a comparable level of risk. These financial instruments have been categorized as Level 3 because the Company considers the rates used in the valuation techniques to be unobservable inputs.

The only significant unobservable input in the discounted cash flow model is the discount rate. For the fair value of the Company's unsecured notes, the Company uses a discount rate based on the indicative new issue pricing provided by lenders. For the Company's mortgage loans, the Company uses an estimate based on its knowledge of the mortgage market. The weighted average discount rate for the combined variable rate debt and mortgage loans used as of September 30, 2013 was 3.337%. An increase in the discount rate used in the discounted cash flow model would result in a decrease to the fair value of the Company's long-term debt. Conversely, a decrease in the discount rate used in the discounted cash flow model would result in an increase to the fair value of the Company's long-term debt.

Disclosure about the fair value of financial instruments is based upon pertinent information available to management as of September 30, 2013 and December 31, 2012. Although management is not aware of any factors that would significantly affect the fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since September 30, 2013, and current estimates of fair value may differ from the amounts presented herein.

9. RISK MANAGEMENT AND USE OF FINANCIAL INSTRUMENTS

Risk Management

In the course of its ongoing business operations, the Company encounters economic risk. There are three main components of economic risk: interest rate risk, credit risk and market risk. The Company is subject to interest rate risk on its interest-bearing liabilities. Credit risk is primarily the risk of inability or unwillingness of tenants to make contractually required payments and of counterparties on derivatives contracts to fulfill their obligations. Market risk is the risk of declines in the value of Company properties due to changes in rental rates, interest rates, supply and demand of similar products and other market factors affecting the valuation of properties.

Risks and Uncertainties

Challenging economic conditions have reduced the volume of real estate transactions and created credit stresses on many businesses. Vacancy rates may increase through the remainder of 2013 and possibly beyond as the current economic climate continues to negatively impact tenants. The current financial markets also have an adverse effect on the Company’s Real Estate Venture partners and contractual counter parties, including counter parties in derivative contracts.

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The Company was in compliance with all financial covenants as of September 30, 2013. Management continuously monitors the Company’s compliance with and anticipated compliance with the covenants. Certain of the covenants restrict the Company’s ability to obtain alternative sources of capital. While the Company currently believes it will remain in compliance with its covenants, in the event of a continued slow-down or deterioration in the economy, the Company may not be able to remain in compliance with such covenants, in which case a default would result absent a lender waiver.

Derivative Financial Instruments

The following table summarizes the terms and fair values of the Company's derivative financial instruments as of September 30, 2013 and December 31, 2012. The notional amounts provide an indication of the extent of the Company's involvement in these instruments at that time, but do not represent exposure to credit, interest rate or market risks (amounts presented in thousands).

Hedge Product	Hedge Type	Designation		Notional Amount				Strike		Trade Date	Maturity Date	Fair value
				09/30/2013		12/31/2012						09/30/2013			12/31/2012
Assets:
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.300	%	December 22, 2011	January 30, 2021	112			(1,262		)
				$	25,774	$	25,774					$	112		$	(1,262	)
Liabilities:
Swap	Interest Rate	Cash Flow	(a)	$	200,000	$	200,000	3.623	%	December 6-13, 2011	February 1, 2019	$	(2,369	)	$	(8,859	)
Swap	Interest Rate	Cash Flow	(a)	77,000		77,000		2.703	%	December 9-13, 2011	February 1, 2016	(942		)	(1,343		)
Swap	Interest Rate	Cash Flow	(a)	50,000		50,000		2.470	%	December 13, 2011	February 1, 2015	(327		)	(458		)
Swap	Interest Rate	Cash Flow	(a)	23,000		23,000		2.513	%	December 7-12, 2011	May 1, 2015	(181		)	(245		)
Swap	Interest Rate	Cash Flow	(a)	27,062		27,062		2.750	%	December 21, 2011	September 30, 2017	(410		)	(914		)
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.090	%	January 6, 2012	October 30, 2019	(85		)	(1,129		)
				$	402,836	$	402,836					$	(4,314	)	$	(12,948	)

(a) Hedging unsecured variable rate debt.

The Company measures its derivative instruments at fair value and records them in the balance sheet as either an asset or liability. As of September 30, 2013, one interest rate swap held an asset position and was included in other assets on the Company's consolidated balance sheets. The remaining swaps are included in other liabilities on the Company's consolidated balance sheets.

Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. The Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy.

Concentration of Credit Risk

Concentrations of credit risk arise for the Company when multiple tenants of the Company are engaged in similar business activities, or are located in the same geographic region, or have similar economic features that impact in a similar manner their ability to meet contractual obligations, including those to the Company. The Company regularly monitors its tenant base to assess potential concentrations of credit risk. Management believes the current credit risk portfolio is reasonably well diversified and does not contain an unusual concentration of credit risk. No tenant accounted for 10% or more of the Company’s rents during the three and nine-month periods ended September 30, 2013 and 2012. Conditions in the general economy and the global credit markets have had a significant adverse effect on numerous industries. The Company has tenants concentrated in various industries that may be experiencing adverse effects from the current economic conditions and the Company could be adversely affected if such tenants were to default under their leases.

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10. DISCONTINUED OPERATIONS

For the three and nine-month periods ended September 30, 2013, income from discontinued operations relates to the twelve properties sold by the Company during 2013, as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The Company determined the property met the criteria for assets held-for-sale pursuant to the related requirements provided for the classification as held for sale under the accounting standard for long lived assets. Accordingly, at September 30, 2013, the property is required to be measured at the lower of its carrying value or the estimated fair value less costs to sell. No provision for impairment was recognized at September 30, 2013 as the estimated fair value of the property less costs to sell are higher than the carrying value based on a purchase and sale agreement. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2013 (in thousands):

	Three-month period ended September 30, 2013			Nine-month period ended  September 30, 2013
Revenue:
Rents	$	—		$	4,129
Tenant reimbursements	3			334
Other	—			123
Total revenue	3			4,586
Expenses:
Property operating expenses	38			1,672
Real estate taxes	17			557
Depreciation and amortization	18			1,769
Total operating expenses	73			3,998
Other income:
Interest income	—			2
Income (Loss) from discontinued operations before gain on sale of interests in real estate	(70		)	590
Net gain (loss) on disposition of discontinued operations	(16		)	3,029
Income (Loss) from discontinued operations	$	(86	)	$	3,619

The following table summarizes balance sheet information for one property designated as held-for-sale as of September 30, 2013 (in thousands);

	September 30,
	2013
Real Estate Investments:
Operating properties	$	3,724
Accumulated depreciation	(1,399		)
	2,325
Construction-in-progress	—
	2,325
Other assets	46
Total assets held for sale	$	2,371

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For the three and nine-month periods ended September 30, 2012, income from discontinued operations relates to the 26 properties sold by the Company from January 1, 2012 through September 30, 2013 as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2012 (in thousands):

	Three-month period ended September 30, 2012		Nine-month period ended  September 30, 2012
Revenue:
Rents	$	5,602	$	22,282
Tenant reimbursements	386		1,872
Termination fees	4		11
Other	129		318
Total revenue	6,121		24,483
Expenses:
Property operating expenses	1,977		6,863
Real estate taxes	707		2,717
Depreciation and amortization	1,788		8,106
Total operating expenses	4,472		17,686
Other income:
Interest income	—		6
Income from discontinued operations before gain on sale of interests in real estate	1,649		6,803
Net gain on disposition of discontinued operations	9,940		34,774
Income from discontinued operations	$	11,589	$	41,577

Discontinued operations have not been segregated in the consolidated statements of cash flows. Therefore, amounts for certain captions will not agree with respective data in the consolidated statements of operations.

11. NON-CONTROLLING INTERESTS IN THE PARENT COMPANY

Non-controlling interests in the Parent Company’s financial statements relate to redeemable common limited partnership interests in the Operating Partnership held by parties other than the Parent Company.

As of September 30, 2013 and December 31, 2012, the aggregate book value of the non-controlling interests associated with the redeemable common limited partnership interests in the accompanying consolidated balance sheet of the Parent Company was $20.3 million and $21.2 million, respectively. The Parent Company believes that the aggregate settlement value of these interests (based on the number of units outstanding and the closing price of the common shares on the balance sheet date) was approximately $23.2 million and $22.5 million, respectively, as of September 30, 2013 and December 31, 2012.

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12. BENEFICIARIES’ EQUITY OF THE PARENT COMPANY

Earnings per Share (EPS)

The following tables detail the number of shares and net income used to calculate basic and diluted earnings per share (in thousands, except share and per share amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Net (income) from continuing operations attributable to non-controlling interests	(106		)	(106		)	(49		)	(49		)
Amount allocable to unvested restricted shareholders	(85		)	(85		)	(95		)	(95		)
Preferred share dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common shareholders	9,258			9,258			2,571			2,571
Income (Loss) from discontinued operations	(86		)	(86		)	11,589			11,589
Discontinued operations attributable to non-controlling interests	1			1			(211		)	(211		)
Discontinued operations attributable to common shareholders	(85		)	(85		)	11,378			11,378
Net income attributable to common shareholders	$	9,173		$	9,173		$	13,949		$	13,949
Denominator
Weighted-average shares outstanding	156,703,348			156,703,348			143,424,485			143,424,485
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average shares outstanding	156,703,348			157,992,082			143,424,485			144,128,010
Earnings per Common Share:
Income from continuing operations attributable to common shareholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common shareholders	—			—			0.08			0.08
Net income attributable to common shareholders	$	0.06		$	0.06		$	0.10		$	0.10

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	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Net (income) loss from continuing operations attributable to non-controlling interests	(147		)	(147		)	335			335
Amount allocable to unvested restricted shareholders	(278		)	(278		)	(286		)	(286		)
Preferred share dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred share redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common shareholders	12,968			12,968			(18,223		)	(18,223		)
Income from discontinued operations	3,619			3,619			41,577			41,577
Discontinued operations attributable to non-controlling interests	(48		)	(48		)	(760		)	(760		)
Discontinued operations attributable to common shareholders	3,571			3,571			40,817			40,817
Net income attributable to common shareholders	$	16,539		$	16,539		$	22,594		$	22,594
Denominator
Weighted-average shares outstanding	151,933,441			151,933,441			143,182,911			143,182,911
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average shares outstanding	151,933,441			153,142,825			143,182,911			143,182,911
Earnings per Common Share:
Income (Loss) from continuing operations attributable to common shareholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common shareholders	0.02			0.02			0.29			0.29
Net income attributable to common shareholders	$	0.11		$	0.11		$	0.16		$	0.16

Redeemable common limited partnership units totaling 1,763,739 and 2,657,721 as of September 30, 2013 and 2012, respectively, were excluded from the diluted earnings per share computations because their effect would have been anti-dilutive.

The contingent securities/share based compensation impact is calculated using the treasury stock method and relates to employee awards settled in shares of the Parent Company. The effect of these securities is anti-dilutive for periods that the Parent Company incurs a net loss from continuing operations available to common shareholders and therefore is excluded from the dilutive earnings per share calculation in such periods.

Unvested restricted shares are considered participating securities which require the use of the two-class method for the computation of basic and diluted earnings per share. For the nine months ended September 30, 2013 and 2012, earnings representing nonforfeitable dividends as noted in the table above were allocated to the unvested restricted shares issued to the Company’s executives and other employees under the 1997 Plan.

Common and Preferred Shares

On September 10, 2013, the Parent Company declared a distribution of $0.15 per common share, totaling $23.8 million, which was paid on October 18, 2013 to shareholders of record as of October 4, 2013. On September 10, 2013, the Parent Company declared distributions on its Series E Preferred Shares to holders of record as of September 30, 2013. These shares are entitled to a preferential return of 6.90% per annum on the $25.00 per share liquidation preference. Distributions paid on October 15, 2013 to holders of Series E Preferred Shares totaled $1.7 million.

On April 10, 2013, the Parent Company closed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating

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Partnership. The Operating Partnership continues to use the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

In March 2010, the Parent Company commenced a continuous equity offering program (the “Offering Program”), that provided for the Parent Company's sale, from time to time until the Offering Program's expiration on March 10, 2013, of up to an aggregate of 15,000,000 common shares in amounts and at times determined by the Parent Company. The Parent Company determined to sell shares under the Offering Program based on a variety of factors, including the trading price of its common shares, overall market conditions and the Parent Company's needs for and assessment of alternative sources of capital. Under the Offering Program, the Parent Company engaged sales agents, who received compensation of up to 2% of the gross sales price per share sold. From January 1, 2013 through the expiration of the Offering Program, the Parent Company did not sell any shares under the Offering Program. From the inception of the Offering Program in March 2010 through its expiration, the Parent Company sold an aggregate of 6,421,553 common shares under the Offering Program at an average sales price of $12.50 per share. The Parent Company contributed the net proceeds from the sale of its shares to the Operating Partnership in exchange for the issuance of 6,421,553 common partnership units to the Parent Company. The Operating Partnership used the net proceeds contributed to it by the Parent Company to repay balances on credit facilities and for general corporate purposes.

Common Share Repurchases

The Parent Company maintains a share repurchase program under which it may repurchase its common shares from time to time in accordance with limits set by the Board of Trustees.

The Parent Company did not repurchase any shares under the share repurchase program during the nine-month period ended September 30, 2013. As of September 30, 2013, the Parent Company may purchase an additional 539,200 shares under the current program limits.

Repurchases may be made from time to time in the open market or in privately negotiated transactions, subject to market conditions and compliance with legal requirements. The share repurchase program does not contain any time limitation and does not obligate the Parent Company to repurchase any shares. The Parent Company may discontinue the program at any time.

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13. PARTNERS’ EQUITY OF THE OPERATING PARTNERSHIP

Earnings per Common Partnership Unit

The following tables detail the number of units and net income used to calculate basic and diluted earnings per common partnership unit (in thousands, except unit and per unit amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Amount allocable to unvested restricted unitholders	(85		)	(85		)	(95		)	(95		)
Preferred unit dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common unitholders	9,364			9,364			2,620			2,620
Discontinued operations attributable to common unitholders	(86		)	(86		)	11,589			11,589
Net income attributable to common unitholders	$	9,278		$	9,278		$	14,209		$	14,209
Denominator
Weighted-average units outstanding	158,467,087			158,467,087			146,082,206			146,082,206
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average units outstanding	158,467,087			159,755,821			146,082,206			146,785,731
Earnings per Common Partnership Unit:
Income from continuing operations attributable to common unitholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common unitholders	—			—			0.08			0.08
Net income attributable to common unitholders	$	0.06		$	0.06		$	0.10		$	0.10

	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Amount allocable to unvested restricted unitholders	(278		)	(278		)	(286		)	(286		)
Preferred unit dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred unit redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common unitholders	13,115			13,115			(18,558		)	(18,558		)
Discontinued operations attributable to common unitholders	3,619			3,619			41,577			41,577
Net income attributable to common unitholders	$	16,734		$	16,734		$	23,019		$	23,019
Denominator
Weighted-average units outstanding	153,731,070			153,731,070			145,842,872			145,842,872
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average units outstanding	153,731,070			154,940,454			145,842,872			145,842,872
Earnings per Common Partnership Unit:
Income (Loss) from continuing operations attributable to common unitholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common unitholders	0.02			0.02			0.29			0.29
Net income attributable to common unitholders	$	0.11		$	0.11		$	0.16		$	0.16

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Unvested restricted units are considered participating securities which require the use of the two-class method for the computation of basic and diluted earnings per share. For the nine months ended September 30, 2013 and 2012, earnings representing nonforfeitable dividends as noted in the table above were allocated to the unvested restricted units.

Common Partnership Units and Preferred Mirror Units

On September 10, 2013, the Operating Partnership declared a distribution of $0.15 per common partnership unit, totaling $23.8 million, which was paid on October 18, 2013 to unitholders of record as of October 4, 2013.

On September 10, 2013, the Operating Partnership declared distributions on its Series E-Linked Preferred Mirror Units to holders of record as of September 30, 2013. These units are entitled to a preferential return of 6.90% per annum on the $25.00 per unit liquidation preference. Distributions paid on October 15, 2013 to holders of Series E-Linked Preferred Mirror Units totaled $1.7 million.

On April 10, 2013, the Parent Company closed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership continues to use the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

From January 1, 2013 through expiration of the Offering Program on March 10, 2013, the Parent Company did not sell any shares under the Offering Program and, accordingly, the Operating Partnership did not issue any common partnership units to the Parent Company in connection with the Offering Program during this time. From the inception of the Offering Program in March 2010 through expiration of the Offering Program in March 2013, the Parent Company sold an aggregate of 6,421,553 common shares under the Offering Program at an average sales price of $12.50 per share. The Operating Partnership used the net proceeds contributed to it by the Parent Company to repay balances on credit facilities and for general corporate purposes.

Common Unit Repurchases

The Parent Company did not repurchase any shares under its share repurchase program during the nine-month period ended September 30, 2013 and accordingly, during the nine-month period ended September 30, 2012, the Operating Partnership did not repurchase any units in connection with the Parent Company’s share repurchase program.

14. SHARE BASED AND DEFERRED COMPENSATION

Stock Options

At September 30, 2013, options exercisable for 2,827,517 common shares were outstanding under the Parent Company's shareholder approved equity incentive plan. There were 184,429 options unvested as of September 30, 2013 and $0.2 million of unrecognized compensation expense associated with these options to be recognized over a weighted average term of 0.4 years. During the three and nine-month periods ended September 30, 2013 the Company recognized compensation expense related to unvested options of $0.2 million and $0.6 million, of which a nominal amount and $0.1 million, respectively, were capitalized. During the three and nine-month periods ended September 30, 2012 the Company recognized compensation expense related to unvested options of $0.4 million and $1.1 million, of which $0.1 million and $0.3 million, respectively, were capitalized consistent with the Company’s policies for capitalizing eligible portions of employee compensation.

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Option activity as of September 30, 2013 and changes during the nine months ended September 30, 2013 were as follows:

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at January 1, 2013	3,337,549		$	14.50	7.2	$	—
Granted	—		—		—	—
Exercised	(207,941	)	$	10.52	—	—
Canceled	(117,662	)	$	18.61
Outstanding at September 30, 2013	3,011,946		$	15.40	5.4	$	—
Vested/Exerciseable at September 30, 2013	2,827,517		$	15.63	5.3	$	—

Restricted Share Awards

As of September 30, 2013, 563,713 restricted shares were outstanding under the 1997 Plan and vest over three to seven years from the initial grant date. At September 30, 2013, approximately $2.4 million of compensation expense remained to be recognized and is expected to be recognized over a weighted average remaining vesting period of 1.4 years. The Company recognized compensation expense related to outstanding restricted shares of $0.9 million and $2.6 million during the three and nine-month periods ended September 30, 2013, of which $0.1 million and $0.4 million, respectively, were capitalized as part of the Company’s policies for capitalizing eligible portions of employee compensation. The Company recognized compensation expense related to outstanding restricted shares of $0.8 million and $2.3 million during the three and nine-month periods ended September 30, 2012, of which $0.2 million and $0.5 million, respectively, were capitalized. The expensed amounts are included in general and administrative expense on the Company’s consolidated statement of operations in the respective periods.

The following table summarizes the Company’s restricted share activity for the nine months ended September 30, 2013:

	Shares		Weighted Average Grant Date Fair value
Non-vested at January 1, 2013	597,708		$	9.46
Granted	182,576		13.13
Vested	(208,306	)	13.13
Forfeited	(8,265	)	11.41
Non-vested at September 30, 2013	563,713		$	12.56

On February 25, 2013, the Compensation Committee of the Parent Company’s Board of Trustees awarded 157,208 restricted shares to the Company’s executives. The restricted shares will cliff vest after three years from the grant date. The vesting of the restricted shares is also subject to acceleration upon a change in control or if the recipient of the award were to die, become disabled or retire in a qualifying retirement. In the case of two of the Company's executives who have employment agreements with the Company, the vesting of the restricted shares is also subject to acceleration if either executive were to be terminated without cause or resign for good reason. Qualifying retirement means the recipient’s voluntary termination of employment after reaching at least age 57 and accumulating at least 15 years of service with the Company. In accordance with the accounting standard for stock-based compensation, the Company amortizes stock-based compensation costs through the qualifying retirement dates for those executives who meet the conditions for qualifying retirement during the scheduled vesting period.

Restricted Performance Share Units Plan

On each of February 25, 2013, March 1, 2012 and March 2, 2011, the Compensation Committee of the Parent Company’s Board of Trustees awarded an aggregate of 231,093, 242,122, and 113,256 share-based awards, respectively, to its executives. These awards are referred to as Restricted Performance Share Units, or RPSUs. The RPSUs represent the right to earn common shares. The number of common shares, if any, deliverable to award recipients depends on the Company’s performance based on its total return to shareholders during the three years measurement period that commenced on January 1, 2013 (in the case of the February 25, 2013 awards), January 1, 2012 (in the case of the March 1, 2012 awards), and January 1, 2011 (in the case of the March 2, 2011 awards), and that ends on December 31, 2015, December 31, 2014 or December 31, 2013 (as applicable) or, if earlier, the date of a change of control. In the case of the awards made on February 25, 2013 and March 1, 2012, the Company's performance

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is compared to the shareholder return of REITs within an index over the measurement period for 50% of the RPSUs awarded on that date, with the remaining 50% being compared to the total shareholder return of REITs within the Company's proxy peer group over such period. In the case of the awards made on March 2, 2011, the Company's performance is compared to the total shareholder return of REITs within an index over the performance period. The vesting of RPSUs is contingent upon the continued employment of the participants through the performance periods (with exceptions for death, disability and qualifying retirement). Dividends are deemed credited to the performance units accounts and are applied to “acquire” additional RPSUs for the account of the unit holder at the price per common share on the dividend payment date. If earned, RPSUs will be settled in common shares in an amount that reflects both the number of RPSUs in the holder’s account at the end of the applicable measurement period and the Company’s total return to shareholders during the applicable three year measurement period relative to the total shareholder returns of the REITs within the index or peer group, as applicable.

On the date of each grant, the RPSUs were valued using a Monte Carlo simulation. The fair values of the 2013, 2012 and 2011 awards on the grant dates were $4.1 million, $4.2 million and $2.0 million, respectively. The fair values of each award are being amortized over the three year cliff vesting period. The vesting of RPSUs is subject to acceleration upon a change in control or if the recipient of the award were to die, become disabled or retire in a qualifying retirement prior to the vesting date. In the case of two of the Company's executives who have employment agreements with the Company, the vesting of the restricted shares is also subject to acceleration if either executive were to be terminated without cause or resign for good reason. Qualifying retirement means the recipient’s voluntary termination of employment after reaching age 57 and accumulating at least 15 years of service with the Company. In accordance with the accounting standard for stock-based compensation, the Company amortizes stock-based compensation costs through the qualifying retirement date for those executives who meet the conditions for qualifying retirement during the schedule vesting period.

For the three and nine-month periods ended September 30, 2013, the Company recognized total compensation expense for the 2013, 2012 and 2011 RPSU awards of $1.3 million and $3.7 million, of which $0.2 million and $0.6 million, respectively, were capitalized consistent with the Company’s policies for capitalizing eligible portions of employee compensation. For the three and nine-month periods ended September 30, 2012, the Company recognized total compensation expense for the 2012, 2011 and 2010 awards of $0.7 million and $2.1 million, of which $0.2 million and $0.6 million, respectively, were capitalized.

A total of 64,678 common shares vested on December 31, 2012 (the end of the three-year measurement period for the linked RPSUs) and were delivered to holders of the RPSUs on March 1, 2013 in settlement of the RPSUs. Holders of these RPSUs also received cash dividend equivalents to the cash dividends paid on common shares on February 8, 2013.

15. TAX CREDIT TRANSACTIONS

Historic Tax Credit Transaction

On November 17, 2008, the Company closed a transaction with US Bancorp (“USB”) related to the historic rehabilitation of the IRS Philadelphia Campus, a 862,692 square foot office building that is 100% leased to the IRS. On August 27, 2010, the Company completed the development of the IRS Philadelphia Campus and the IRS lease commenced. In connection with this completed development project, USB contributed to the Company $64.1 million of total project costs.

In exchange for its contributions to the development of the IRS Philadelphia Campus, USB is entitled to substantially all of the benefits derived from the tax rehabilitation credits available under section 47 of the Internal Revenue Code. USB does not have a material interest in the underlying economics of the property. This transaction includes a put/call provision whereby the Company may be obligated or entitled to repurchase USB’s interest in the IRS Philadelphia Campus. The Company believes the put will be exercised and the amount attributed to that puttable non-controlling interest obligation is included in other liabilities and is being accreted to the expected fixed put price.

Based on the contractual arrangements that obligate the Company to deliver tax benefits and provide other guarantees to USB and that entitle the Company through fee arrangements to receive substantially all available cash flow from the IRS Philadelphia Campus, the Company concluded that the IRS Philadelphia Campus should be consolidated. The Company also concluded that capital contributions received from USB, in substance, are consideration that the Company receives in exchange for its obligation to deliver tax credits and other tax benefits to USB. These receipts other than the amounts allocated to the put obligation will be recognized as revenue in the consolidated financial statements beginning when the obligation to USB is relieved which occurs upon delivery of the expected tax benefits net of any associated costs. The tax credit is subject to 20% recapture per year beginning one year after the completion of the IRS Philadelphia Campus. The total USB contributions presented within the Company’s consolidated balance sheet amounted to $26.8 million and $39.1 million as of September 30, 2013 and December 31, 2012, respectively. The contributions were recorded net of the amount allocated to non-controlling interest as described above of $2.7 million at the end of the period ended September 30, 2013 and $2.6 million at December 31, 2012, with the remaining balance being presented within deferred income. Beginning in September 2011 to September 2015, the Company recognized and will

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recognize, on an annual basis, the cash received as revenue net of allocated expenses over the five year credit recapture period as defined in the Internal Revenue Code within other income (expense) in its consolidated statements of operations. During the nine-month period ended September 30, 2013 the Company recognized $11.9 million in income related to the tax credits.

Direct and incremental costs incurred in structuring the transaction are deferred and will be recognized as expense in the consolidated financial statements upon the recognition of the related revenue as discussed above. The deferred cost at September 30, 2013 and December 31, 2012 is $1.0 million and $1.6 million, respectively, and is included in other assets in the Company’s consolidated balance sheet. Amounts included in interest expense related to the accretion of the non-controlling interest liability and the 2% return expected to be paid to USB on its non-controlling interest aggregate to $0.3 million and $1.0 million for the three and nine-month periods ended September 30, 2013, respectively, and $0.3 million and $1.0 million for the three and nine-month periods ended September 30, 2012, respectively.

New Markets Tax Credit Transaction

On December 30, 2008, the Company entered into a transaction with USB related to the Cira South Garage in Philadelphia, Pennsylvania and expects to receive a net benefit of $7.8 million under a qualified New Markets Tax Credit Program (“NMTC”). The NMTC was provided for in the Community Renewal Tax Relief Act of 2000 (the “Act”) and is intended to induce investment capital in under-served and impoverished areas of the United States. The Act permits taxpayers (whether companies or individuals) to claim credits against their Federal income taxes for up to 39% of qualified investments in qualified, active low-income businesses or ventures.

USB contributed $13.3 million to the development of the Cira South Garage and as such it is entitled to substantially all of the benefits derived from the tax credit, but it does not have a material interest in the underlying economics of the Cira South Garage. This transaction also includes a put/call provision whereby the Company may be obligated or entitled to repurchase USB’s interest. The Company believes the put will be exercised and an amount attributed to that obligation is included in other liabilities and is being accreted to the expected fixed put price. This put price is insignificant.

Based on the contractual arrangements that obligate the Company to deliver tax benefits and provide various other guarantees to USB, the Company concluded that the investment entities established to facilitate the NMTC transaction should be consolidated. The USB contribution of $13.3 million is included in deferred income on the Company’s consolidated balance sheets at each of September 30, 2013 and December 31, 2012. The USB contribution other than the amount allocated to the put obligation will be recognized as income in the consolidated financial statements when the tax benefits are delivered without risk of recapture to the tax credit investors and the Company’s obligation is relieved. The Company anticipates that it will recognize the net cash received as revenue within other income/expense in the year ended December 31, 2015. The NMTC is subject to 100% recapture for a period of seven years as provided in the Internal Revenue Code. The Company expects that the put/call provision will be exercised in 2017.

Direct and incremental costs incurred in structuring the transaction are deferred and will be recognized as expense in the consolidated financial statements upon the recognition of the related revenue as discussed above. The deferred cost at each of September 30, 2013 and December 31, 2012 is $5.3 million, and is included in other assets in the Company’s consolidated balance sheet.

16. SEGMENT INFORMATION

As of September 30, 2013, the Company was managing its portfolio within seven geographic segments: (1) Pennsylvania, (2) Philadelphia Central Business District (CBD), (3) Metropolitan Washington D.C., (4) New Jersey/Delaware, (5) Richmond, Virginia, (6) Austin, Texas and (7) California. The Pennsylvania segment includes properties in Chester, Delaware, and Montgomery counties in the Philadelphia suburbs. The Philadelphia CBD segment includes properties located in the City of Philadelphia in Pennsylvania. The Metropolitan Washington, D.C. segment includes properties in Northern Virginia and southern Maryland. The New Jersey/Delaware segment includes properties in Burlington, Camden and Mercer counties in New Jersey and in New Castle county in the state of Delaware. The Richmond, Virginia segment includes properties primarily in Albemarle, Chesterfield, Goochland and Henrico counties and one property in Durham, North Carolina. The Austin, Texas segment includes properties in Austin. The California segment includes properties in Oakland, Concord, and Carlsbad, California. The corporate group is responsible for cash and investment management, development of certain real estate properties during the construction period, and certain other general support functions. Land held for development and construction in progress are transferred to operating properties by region upon completion of the associated construction or project.

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Segment information is as follows (in thousands):

	Pennsylvania Suburbs		Philadelphia CBD		Metropolitan, D.C.		New Jersey/Delaware		Richmond, Virginia		Austin, Texas		California		Corporate			Total
As of September 30, 2013:
Real estate investments, at cost:
Operating properties	$	1,196,987	$	1,026,116	$	1,207,243	$	410,143	$	309,646	$	289,075	$	192,700	$	—		$	4,631,910
Construction-in-progress															52,702			52,702
Land inventory															94,097			94,097
As of December 31, 2012:
Real estate investments, at cost:
Operating properties	$	1,178,730	$	988,590	$	1,193,200	$	546,644	$	309,923	$	285,346	$	223,736	$	—		$	4,726,169
Construction-in-progress															48,950			48,950
Land inventory															102,439			102,439
For the three-months ended September 30, 2013:
Total revenue	$	39,268	$	35,891	$	29,320	$	16,171	$	8,640	$	9,937	$	4,632	$	(403	)	$	143,456
Property operating expenses, real estate taxes and third party management expenses	13,291		13,704		10,321		8,647		3,735		3,958		2,531		(19		)	56,168
Net operating income	$	25,977	$	22,187	$	18,999	$	7,524	$	4,905	$	5,979	$	2,101	$	(384	)	$	87,288
For the three-months ended September 30, 2012:
Total revenue	$	38,373	$	33,026	$	26,516	$	15,536	$	8,826	$	8,274	$	4,448	$	(479	)	$	134,520
Property operating expenses, real estate taxes and third party management expenses	13,463		12,432		10,638		7,930		3,761		3,485		2,362		(504		)	53,567
Net operating income	$	24,910	$	20,594	$	15,878	$	7,606	$	5,065	$	4,789	$	2,086	$	25		$	80,953
For the nine-months ended September 30, 2013:
Total revenue	$	114,730	$	107,957	$	85,889	$	47,449	$	26,359	$	29,067	$	13,773	$	(1,026	)	$	424,198
Property operating expenses, real estate taxes and third party management expenses	40,256		40,826		31,856		23,301		11,017		12,123		7,029		(75		)	166,333
Net operating income	$	74,474	$	67,131	$	54,033	$	24,148	$	15,342	$	16,944	$	6,744	$	(951	)	$	257,865
For the nine-months ended September 30, 2012:
Total revenue	$	113,110	$	98,086	$	79,919	$	46,550	$	26,762	$	23,957	$	13,034	$	(1,305	)	$	400,113
Property operating expenses, real estate taxes and third party management expenses	39,285		37,080		31,156		22,841		10,874		10,494		6,747		(1,274		)	157,203
Net operating income	$	73,825	$	61,006	$	48,763	$	23,709	$	15,888	$	13,463	$	6,287	$	(31	)	$	242,910

Net operating income (“NOI”) is defined as total revenue less property operating expenses, real estate taxes and third party management expenses. Segment NOI includes revenue, real estate taxes and property operating expenses directly related to operation and management of the properties owned and managed within the respective geographical region. Segment NOI excludes property level depreciation and amortization, revenue and expenses directly associated with third party real estate management services, expenses associated with corporate administrative support services, and inter-company eliminations. NOI also does not reflect general and administrative expenses, interest expenses, real estate impairment losses, depreciation and amortization costs, capital expenditures and leasing costs. Trends in development and construction activities that could materially impact the Company’s results from operations are also not reflected in NOI. All companies may not calculate NOI in the same manner. NOI

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is the measure that is used by the Company to evaluate the operating performance of its real estate assets by segment. The Company also believes that NOI provides useful information to investors regarding the Company's financial condition and results of operations because it reflects only those income and expenses recorded at the property level. The Company believes that net income, as defined by GAAP, is the most appropriate earnings measure. Below is a reconciliation of consolidated NOI to consolidated net income, as defined by GAAP:

	Three-month periods ended September 30,						Nine-month periods ended September 30,
	2013			2012			2013			2012
	(amounts in thousands)						(amounts in thousands)
Consolidated net operating income	$	87,288		$	80,953		$	257,865		$	242,910
Less:
Interest expense	(30,338		)	(32,620		)	(91,689		)	(99,745		)
Interest expense - amortization of deferred financing costs	(1,158		)	(1,218		)	(3,502		)	(3,790		)
Interest expense - financing obligation	(264		)	(230		)	(693		)	(608		)
Depreciation and amortization	(50,613		)	(46,955		)	(149,423		)	(142,262		)
General and administrative expenses	(6,436		)	(6,080		)	(20,322		)	(18,209		)
Net loss on sale of undepreciated real estate	(129		)	—			(129		)	—
Loss on real estate venture formation	—			(950		)	—			(950		)
Loss on early extinguishment of debt	(11		)	(51		)	(1,127		)	(1,549		)
Plus:
Interest income	268			311			448			2,631
Historic tax credit transaction income	11,853			11,840			11,853			11,840
Equity in income of real estate ventures	714			500			3,757			1,382
Gain from remeasurement of investment in a real estate venture	—			—			7,847			—
Net gain on real estate venture transactions	—			—			3,683			—
Income (loss) from continuing operations	11,174			5,500			18,568			(8,350		)
Income (loss) from discontinued operations	(86		)	11,589			3,619			41,577
Net income	$	11,088		$	17,089		$	22,187		$	33,227

17. COMMITMENTS AND CONTINGENCIES

Legal Proceedings

The Company is involved from time to time in litigation on various matters, including disputes with tenants and disputes arising out of agreements to purchase or sell properties. Given the nature of the Company’s business activities, these lawsuits are considered routine to the conduct of its business. The result of any particular lawsuit cannot be predicted, because of the very nature of litigation, the litigation process and its adversarial nature, and the jury system. The Company does not expect that the liabilities, if any, that may ultimately result from such legal actions will have a material adverse effect on the consolidated financial position, results of operations or cash flows of the Company.

Environmental

As an owner of real estate, the Company is subject to various environmental laws of federal, state, and local governments. The Company’s compliance with existing laws has not had a material adverse effect on its financial condition and results of operations, and the Company does not believe it will have a material adverse effect in the future. However, the Company cannot predict the impact of unforeseen environmental contingencies or new or changed laws or regulations on its current Properties or on properties that the Company may acquire.

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Ground Rent

Future minimum rental payments under the terms of all non-cancelable ground leases under which the Company is the lessee are expensed on a straight-line basis regardless of when payments are due. The Company’s ground leases have remaining lease terms ranging from 16 to 90 years. Minimum future rental payments on non-cancelable leases at September 30, 2013 are as follows (in thousands):

2013 (three months remaining)	$	549
2014	2,288
2015	2,288
2016	2,288
2017	2,288
Thereafter	280,519
Total	$	290,220

One of the land leases for a property provides for contingent rent participation by the lessor in certain capital transactions and net operating cash flows of the property after certain returns are achieved by the Company. Such amounts, if any, will be reflected as contingent rent when incurred. The leases also provide for payment by the Company of certain operating costs relating to the land, primarily real estate taxes. The above schedule of future minimum rental payments does not include any contingent rent amounts or any reimbursed expenses.

The Company acquired ground tenancy rights under a long term ground lease agreement related to its acquisition of 3020 Market Street in Philadelphia, Pennsylvania on August 12, 2011. The annual rental payments under this ground lease is equal to a percentage of the net operating income generated by the property. The Company has not included the amounts in the table above since such amounts are not fixed or determinable.

Other Commitments or Contingencies

As part of the Company’s September 2004 acquisition of a portfolio of properties from The Rubenstein Company (which the Company refers to as the "TRC acquisition"), the Company acquired its interest in Two Logan Square, a 708,844 square foot office building in Philadelphia, primarily through its ownership of a second and third mortgage secured by this property. This property is consolidated, as the borrower is a variable interest entity and the Company, through its ownership of the second and third mortgages, is the primary beneficiary. The Company currently does not expect to take title to Two Logan Square until, at the earliest, September 2019. If the Company takes fee title to Two Logan Square upon a foreclosure of its mortgage, the Company has agreed to pay an unaffiliated third party that holds a residual interest in the fee owner of this property an amount equal to $2.9 million. On the TRC acquisition date, the Company recorded a liability of $0.7 million and this amount will accrete up to $2.9 million through September 2019. As of September 30, 2013, the Company had a balance of $1.6 million for this liability in its consolidated balance sheet.

The Company was audited by the Internal Revenue Service (the “IRS”) for its 2004 tax year. The audit concerned the tax treatment of the TRC acquisition in September 2004 in which the Company acquired a portfolio of properties through the acquisition of a limited partnership. On December 17, 2010, the Company received notice that the IRS proposed an adjustment to the allocation of recourse liabilities allocated to the contributor of the properties. The Company appealed the proposed adjustment and during the second quarter of 2013, the IRS finalized a settlement agreement which will not result in a material liability to the Company for federal income taxes. The contributor of partnership interests in the 2004 transaction has agreed not to assert a claim against the Company for federal income tax purposes under the tax protection agreement entered into as part of the transaction.

As part of the Company’s 2006 merger with Prentiss Properties Trust ("Prentiss"), the 2004 TRC acquisition and several of our other transactions, the Company agreed not to sell certain of the properties it acquired in transactions that would trigger taxable income to the former owners. In the case of the TRC acquisition, the Company agreed not to sell acquired properties in non-exempt transactions for periods up to 15 years from the date of the TRC acquisition as follows at September 30, 2013: One Rodney Square and 130/150/170 Radnor Financial Center (January, 2015); and One Logan Square, Two Logan Square and Radnor Corporate Center (January, 2020). In the Prentiss acquisition, the Company assumed the obligation of Prentiss not to sell Concord Airport Plaza before March, 2018. The Company’s agreements generally provide that it may dispose of the subject properties only in transactions that qualify as tax-free exchanges under Section 1031 of the Internal Revenue Code or in other tax deferred transactions. If the Company were to sell a restricted property before expiration of the restricted period in a non-exempt transaction, the Company may be required to make significant payments to the parties who sold the applicable property on account of tax liabilities attributed to them.

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As part of the Company’s acquisition of properties from time to time in tax-deferred transactions, the Company has agreed to provide certain of the prior owners of the acquired properties with the right to guarantee the Company’s indebtedness. If the Company were to seek to repay the indebtedness guaranteed by the prior owner before the expiration of the applicable agreement, the Company would be required to provide the prior owner an opportunity to guaranty qualifying replacement debt. These debt maintenance agreements may limit the Company’s ability to refinance indebtedness on terms favorable to the Company.

During 2008, in connection with the development of the IRS Philadelphia Campus and the Cira South Garage, the Company entered into a historic tax credit and a new market tax credit arrangement, respectively. The Company is required to be in compliance with various laws, regulations and contractual provisions that apply to its historic and new market tax credit arrangements. Non-compliance with applicable requirements could result in projected tax benefits not being realized and require a refund to USB or reduction of investor capital contributions, which are reported as deferred income in the Company’s consolidated balance sheet, until such time as its obligation to deliver tax benefits is relieved. The compliance periods for the tax credit arrangements run through 2015. The Company does not anticipate that any material refunds or reductions of investor capital contributions will be required in connection with these arrangements.

The Company invests in its properties and regularly incurs capital expenditures in the ordinary course to maintain the properties. The Company believes that such expenditures enhance its competitiveness. The Company also enters into construction, utility and service contracts in the ordinary course of business which may extend beyond one year. These contracts typically provide for cancellation with insignificant or no cancellation penalties.

18. SUBSEQUENT EVENTS

Austin Venture

On October 16, 2013, the Company contributed a portfolio of seven office properties containing an aggregate of 1,398,826 square feet located in Austin, Texas (the "Austin Properties") to a newly-formed joint venture (the "Austin Venture") with G&I VII Austin Office LLC (“DRA”), an investment vehicle advised by DRA Advisors LLC. The Austin Properties and related assets represent the Company's entire remaining property portfolio within the Austin, Texas region. DRA and the Company, based on arm's-length negotiation, agreed to an aggregate gross sales price of $330.0 million subject to an obligation on the Company's part to fund the first $5.2 million of post-closing capital expenditures.

DRA owns a 50% interest in the Austin Venture and the Company owns a 50% interest in the Austin Venture, subject to the Company's right to receive up to an additional 10% of distributions.

At the closing the Austin Venture obtained third party non-recourse debt financing of approximately $230.6 million secured by mortgages on the Austin Properties and used proceeds of this financing together with $49.7 million of cash contributions by DRA (less $1.9 million of closing costs and $6.9 million of closing prorations and lender holdbacks) to fund a $271.5 million distribution to the Company. The Company has agreed to fund the first $5.2 million of post-closing capital expenditures on behalf of the Austin Venture, resulting in net proceeds of $266.3 million after funding the Company's capital expenditure obligation. As part of the transaction, the Company's subsidiary management company executed an agreement with the Austin Venture to provide property management and leasing services to the Austin Venture in exchange for a market-based fee.

The Company and DRA, utilizing additional equity funding of up to $100.0 million per partner and to-be-determined third-party debt financing, intend to jointly pursue additional office opportunities in targeted Austin sub-markets and plan to co-invest in acquisitions that meet certain investment criteria.

Cira Walnut Tower

On October 31, 2013 the Company signed a lease with FMC Corporation for approximately 245,000 square feet of office space at the Cira Walnut Tower ("Cira Walnut"), which is an office and residential tower that the Company will develop at 30th and Walnut Streets in Philadelphia on a site ground leased from the University of Pennsylvania. The lease with FMC has an initial term of sixteen (16) years from initial occupancy. In addition, the Company also leased approximately 100,000 square feet of office space to the University of Pennsylvania under a twenty-year lease. Cira Walnut will be known as The FMC Tower at Cira Centre South.

The Company's ground lease with the University of Pennsylvania has a term through July 2097, with a variable rent that would provide the University with a percentage of the cash flow or proceeds of specified capital events subject to receipt by the Company of a priority return on the Company's investment.

The Company has evaluated subsequent events through the date the financial statements were issued.

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Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The Private Securities Litigation Reform Act of 1995 provides a “safe harbor” for forward-looking statements. This Quarterly Report on Form 10-Q and other materials filed by us with the SEC (as well as information included in oral or other written statements made by us) contain statements that are forward-looking, including statements relating to business and real estate development activities, acquisitions, dispositions, future capital expenditures, financing sources, governmental regulation (including environmental regulation) and competition. We intend such forward-looking statements to be covered by the safe-harbor provisions of the 1995 Act. The words “anticipate,” “believe,” “estimate,” “expect,” “intend,” “will,” “should” and similar expressions, as they relate to us, are intended to identify forward-looking statements. Although we believe that the expectations reflected in such forward-looking statements are based on reasonable assumptions, we can give no assurance that our expectations will be achieved. As forward-looking statements, these statements involve important risks, uncertainties and other factors that could cause actual results to differ materially from the expected results and, accordingly, such results may differ from those expressed in any forward-looking statements made by us or on our behalf. Factors that could cause actual results to differ materially from our expectations include, but are not limited to:

• the continuing impact of modest global economic growth, which is having and may continue to have a negative effect on the following, among other things:

• the fundamentals of our business, including overall market occupancy, demand for office space and rental rates;

• the financial condition of our tenants, many of which are financial, legal and other professional firms, our lenders, counterparties to our derivative financial instruments and institutions that hold our cash balances and short-term investments, which may expose us to increased risks of default by these parties;

• the availability of financing on attractive terms or at all, which may adversely impact our future interest expense and our ability to pursue acquisition and development opportunities and refinance existing debt; and

• a decline in real estate asset valuations, which may limit our ability to dispose of assets at attractive prices or obtain or maintain debt financing secured by our properties or on an unsecured basis.

• changes in local real estate conditions (including changes in rental rates and the number of properties that compete with our properties);

• changes in the economic conditions affecting industries in which our principal tenants compete;

• the unavailability of equity and debt financing;

• our failure to lease unoccupied space in accordance with our projections;

• our failure to re-lease occupied space upon expiration of leases;

• tenant defaults and the bankruptcy of major tenants;

• increases in interest rates;

• failure of interest rate hedging contracts to perform as expected and the effectiveness of such arrangements;

• failure of acquisitions to perform as expected;

• unanticipated costs associated with the acquisition, integration and operation of our acquisitions;

• unanticipated costs to complete, lease-up and operate our developments and redevelopments;

• unanticipated costs associated with land development, including building moratoriums and inability to obtain necessary zoning, land-use, building, occupancy and other required governmental approvals, construction cost increases or overruns and construction delays;

• impairment losses;

• increased costs for, or lack of availability of, adequate insurance, including for terrorist acts;

• actual or threatened terrorist attacks;

• demand for tenant services beyond those traditionally provided by landlords;

• liability under environmental or other laws;

• failure or bankruptcy of real estate venture partners;

• inability of real estate venture partners to fund venture obligations;

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• failure of dispositions to close in a timely manner;

• failure of buyers of our properties to comply with the terms of their financing agreements to us;

• earthquakes, floodings and other natural disasters;

• the unforeseen impact of climate change and compliance costs relating to laws and regulations governing climate change;

• risks associated with federal, state and local tax audits;

• complex regulations relating to our status as a REIT and the adverse consequences of the Parent Company's failure to qualify as a REIT; and

• the impact of newly adopted accounting principles on our accounting policies and on period-to-period comparisons of financial results.

Given these uncertainties, and the other risks identified in the “Risk Factors” section of our 2012 Annual Report on Form 10-K, we caution readers not to place undue reliance on forward-looking statements. We assume no obligation to update or supplement forward-looking statements that become untrue because of subsequent events.

The discussion that follows is based primarily on our consolidated financial statements as of September 30, 2013 and December 31, 2012 and for the three and nine-month periods ended September 30, 2013 and 2012 and should be read along with the consolidated financial statements and related notes appearing elsewhere in this report. The ability to compare one period to another may be significantly affected by acquisitions completed, development properties placed in service and dispositions made during those periods.

OVERVIEW

As of September 30, 2013, our 210 property portfolio consisted of 182 office properties (one of which is held-for-sale), 19 industrial facilities, five mixed-use properties (205 core properties), one development property, two redevelopment properties and one re-entitlement property that contain an aggregate of approximately 24.1 million net rentable square feet. As of September 30, 2013, we also held economic interests in 18 unconsolidated real estate ventures that we formed with third parties to develop or own commercial properties. The properties owned by these Real Estate Ventures contain approximately 6.2 million net rentable square feet.

As of September 30, 2013, we managed our portfolio within seven geographic segments: (1) Pennsylvania, (2) Philadelphia CBD, (3) Metropolitan Washington, D.C., (4) New Jersey/Delaware, (5) Richmond, Virginia, (6) Austin, Texas and (7) California. The Pennsylvania segment includes properties in Chester, Delaware, and Montgomery counties in the Philadelphia suburbs. The Philadelphia CBD segment includes properties located in the City of Philadelphia in Pennsylvania. The Metropolitan Washington, D.C. segment includes properties in Northern Virginia and southern Maryland. The New Jersey/Delaware segment includes properties in Burlington, Camden, and Mercer counties in New Jersey and New Castle county in the state of Delaware. The Richmond, Virginia segment includes properties primarily in Albemarle, Chesterfield, Goochland and Henrico counties and one property in Durham, North Carolina. The Austin, Texas segment includes properties in Austin. The California segment includes properties in Oakland, Concord, and Carlsbad, California.

We generate cash and revenue from leases of space at our properties, from investments in Real Estate Ventures and, to a lesser extent, from the management of properties owned by third parties. Factors that we evaluate when leasing space include rental rates, costs of tenant improvements, tenant creditworthiness, current and expected operating costs, the length of the lease, vacancy levels and demand for office and industrial space. We also generate cash through sales of assets, including assets that we do not view as core to our portfolio, either because of location or expected growth potential, and assets that are commanding premium prices from third party investors.

Our financial and operating performance is dependent upon the demand for office, industrial and other commercial space in our markets, our leasing results, our acquisition, disposition and development activity, our financing activity, our cash requirements and economic and market conditions, including prevailing interest rates.

Challenging economic conditions could result in a reduction of the availability of financing and potentially in higher borrowing costs. These factors, coupled with ongoing economic recovery, have reduced the volume of real estate transactions and created credit stresses on most businesses. Vacancy rates may increase through the remainder of 2013 and possibly beyond as the current economic climate continues to negatively impact tenants.

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We expect that the impact of the current state of the economy, including continued high unemployment and the continued volatility in the financial and credit markets, could continue to have a dampening effect on the fundamentals of our business, including potential increases in past due accounts, tenant defaults, lower occupancy and reduced effective rents. These conditions would negatively affect our future net income and cash flows and could have a material adverse effect on our financial condition. We believe that the quality of our assets and our strong balance sheet will enable us to raise debt capital, if necessary, in various forms and from different sources, including traditional term or secured loans from banks, pension funds and life insurance companies. However, there can be no assurance that we will be able to borrow funds on terms that are economically attractive or at all.

We seek revenue growth throughout our portfolio by increasing occupancy and rental rates. Occupancy at our wholly owned properties at September 30, 2013 was 88.3%.

The table below summarizes the key operating and leasing statistics of our wholly owned operating properties for the three and nine months ended September 30, 2013:

	Three-month period ended			Nine-month period ended
	September 30, 2013			September 30, 2013
Leasing Activity:
Core portfolio net rentable square feet owned (1)	23,334,037			23,334,037
Occupancy percentage (end of period)	88.3		%	88.3		%
Average occupancy percentage	88.1		%	88.1		%
New leases and expansions commenced (square feet)	447,698			1,227,902
Leases renewed (square feet)	384,691			1,191,804
Net absorption (square feet) (2)	49,290			(54,434		)
Percentage change in rental rates per square feet (3):
New and expansion rental rates	9.3		%	10.5		%
Renewal rental rates	9.5		%	9.6		%
Combined rental rates	9.4		%	9.9		%
Capital Costs Committed (4):
Leasing commissions (per square feet)	$	4.08		$	3.77
Tenant Improvements (per square feet)	$	9.04		$	8.85

(1) Includes all properties in the core portfolio (i.e. not under development or redevelopment or a re-entitlement property), including properties that were sold during these periods.

(2) Includes leasing related to completed developments and redevelopments, as well as properties sold during the nine-month period ended September 30, 2013.

(3) Rental rates include base rent plus reimbursement for operating expenses and real estate taxes.

(4) Calculated on an average basis.

In seeking to increase revenue through our operating, financing and investment activities, we also seek to minimize operating risks, including (i) tenant rollover risk, (ii) tenant credit risk and (iii) development risk.

Tenant Rollover Risk:

We are subject to the risk that tenant leases, upon expiration, will not be renewed, that space may not be relet, or that the terms of renewal or reletting (including the cost of renovations) may be less favorable to us than the current lease terms. Leases accounting for approximately 1.1% of our aggregate final annualized base rents as of September 30, 2013 (representing approximately 1.3% of the net rentable square feet of the Properties) expire without penalty in the remainder of 2013. As of September 30, 2013, the annualized rent per square foot of these expiring leases amounted to $22.03, and although we can provide no assurance, we currently expect that the annualized market rent per square foot will increase by 6% to 8% through a combination of new leases and renewals throughout the year. We maintain an active dialogue with our tenants in an effort to maximize lease renewals. During the nine months ended September 30, 2013, we achieved a 63.1% retention rate in our core portfolio. If we are unable to renew leases or relet space under expiring leases, at anticipated rental rates, or if tenants terminate their leases early, our cash flow would be adversely impacted.

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Tenant Credit Risk:

In the event of a tenant default, we may experience delays in enforcing our rights as a landlord and may incur substantial costs in protecting our investment. Our management regularly evaluates our accounts receivable reserve policy in light of our tenant base and general and local economic conditions. Our accounts receivable allowance was $16.7 million or 10.5% of total receivables (including accrued rent receivables) as of September 30, 2013 compared to $16.6 million or 10.9% of total receivables (including accrued rent receivables) as of December 31, 2012.

If economic conditions deteriorate, we may experience increases in past due accounts, defaults, lower occupancy and reduced effective rents. This condition would negatively affect our future net income and cash flows and could have a material adverse effect on our financial condition.

Development Risk:

As of September 30, 2013, we owned approximately 423 acres of undeveloped land, and held options to purchase approximately 51 additional acres of undeveloped land. As market conditions warrant, we will seek to opportunistically dispose of those parcels that we do not anticipate developing. For parcels of land that we ultimately develop, we will be subject to risks and costs associated with land development, including building moratoriums and the inability to obtain necessary zoning, land-use, building, occupancy and other required governmental approvals, construction cost increases or overruns and construction delays, and insufficient occupancy rates and rental rates. As of September 30, 2013, the total potential development that these land parcels could support amounted to 6.1 million square feet.

We are a party to a development agreement and related ground leases covering two adjacent parcels of land. As described below under "Recent Property Transactions - evo at Cira Centre South Venture" and in Note 4 above, on January 25, 2013, we contributed our development rights in one of the land parcels to the evo at Cira Centre South Venture, and during the three months ended March 31, 2013 the evo at Cira Centre South Venture commenced construction of a student housing tower.

As to the other parcel, we have the right, on terms and conditions in the development agreement and applicable ground lease, to commence development of such other parcel by December 31, 2015. On October 31, 2013 the Operating Partnership determined to proceed with development of the Cira Walnut Tower ("Cira Walnut"), which it contemplates as a 47-story office and residential tower at 30^th and Walnut Streets in Philadelphia on a site ground leased from the University of Pennsylvania. The Operating Partnership expects Cira Walnut to be ready for initial occupancy during the second quarter of 2016.

The Operating Partnership contemplates that Cira Walnut will include approximately 575,000 square feet of office space, 245,000 square feet of residential space consisting of 260 market rate finished and unfinished rental apartment units, and 10,000 square feet of retail space, with an additional floor containing a full range of amenities.

The Operating Partnership has pre-leased an aggregate of 61% of the office square feet of Cira Walnut.  The anchor tenant for approximately 253,000 square feet of office space is FMC Corporation, a diversified chemical company serving agricultural, consumer and industrial markets globally.  The lease with FMC has an initial term of sixteen (16) years from initial occupancy. In addition, the Operating Partnership also leased approximately 100,000 square feet of office space to the University of Pennsylvania under a twenty-year lease.  Cira Walnut will be known as The FMC Tower at Cira Centre South.

The Operating Partnership anticipates the office component of the project will cost approximately $236.0 million with the residential component costing approximately $105.0 million for a total project cost of $341.0 million. 

The Operating Partnership intends to fund the Cira Walnut development costs through a combination of existing cash balances, one or more joint venture formations, proceeds from additional asset sales or equity and debt financing including third party equity sources.

The Operating Partnership's current intention is to either joint venture or pre-sell the residential component of the FMC Tower at Cira Centre South. Pursuant to this objective, the Operating Partnership has executed a non-binding letter of intent with a residential development and operating company that contemplates either outcome.

The Operating Partnership's ground lease with the University of Pennsylvania has a term through July 2097, with a variable rent that would provide the University with a percentage of the cash flow or proceeds of specified capital events subject to receipt of a priority return on the Operating Partnership's investment.

Development projects are subject to a variety of risks, including construction delays, construction cost overruns, inability to obtain financing on favorable terms, inability to lease space at projected rates, inability to enter into construction, development and other

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agreements on favorable terms, and unexpected environmental and other hazards. Reference is made to our Annual Report on Form 10-K for the year ended December 31, 2012 for additional risks associated with development projects.

RECENT PROPERTY TRANSACTIONS

Real Estate Acquisitions/Dispositions

On April 25, 2013, we exercised our purchase option under the long term ground lease agreement we held through our acquisition of Three Logan Square on August 5, 2010 and acquired the 1.8 acre land parcel underlying Three Logan Square in Philadelphia, Pennsylvania for $20.8 million. We have accounted for the transaction as an asset acquisition. A portion of the original purchase price of Three Logan Square was allocated to the below market ground lease intangible asset, as the sum of the purchase price of the land and the $4.3 million remaining balance for the intangible asset approximates the fair value of the land as unencumbered by the ground lease. The remaining intangible asset balance was reclassified to land upon exercise of the purchase option. We funded the cost of the acquisition with available corporate funds and capitalized $0.1 million of acquisition related costs as part of the basis in the operating land.

On August 5, 2013, we sold an eight-acre parcel of land located in Richmond, Virginia known as Dabney Land East, for a sales price of $0.5 million. The land parcel was undeveloped as of the date of sale.

On June 28, 2013, we sold 16870 West Bernardo Drive, a 67,909 net rentable square feet office property located in San Diego, California, for a sales price of $18.0 million. The property was 98.8% occupied as of the date of sale.

On June 28, 2013, we sold 100 Arrandale Boulevard, a 34,931 net rentable square feet office property located in Exton, Pennsylvania, for a sales price of $3.5 million. The property was vacant at the date of sale.

On June 19, 2013, we sold 1700 Paoli Pike, a 28,000 net rentable square feet office property located in Malvern, Pennsylvania, for a sales price of $2.7 million. The property was vacant at the date of sale.

On June 14, 2013, we sold Pacific View Plaza, a 51,695 net rentable square feet office property located in Carlsbad, California, for a sales price of $10.3 million. The property was 90.5% occupied as of the date of sale.

On February 25, 2013, we sold a portfolio of eight office properties containing 800,546 square feet in Lawrenceville, New Jersey for an aggregate sales price of $121.0 million. These properties, collectively known as "Princeton Pike Corporate Center," were 86.9% occupied as of the date of sale.

4040 Wilson Venture

On July 31, 2013, we formed 4040 Wilson LLC Venture ("4040 Wilson"), a joint venture between the Company and Ashton Park Associates LLC (“Ashton Park”), an unaffiliated third party. 4040 Wilson expects to construct a 20-story office building located in the Ballston submarket of Arlington, Virginia. We and Ashton Park each own a 50% interest in 4040 Wilson. 4040 Wilson would develop the project on a 1.3 acre land parcel contributed by Ashton Park at an agreed upon value of $36.0 million. The total estimated project costs are $194.3 million, which the Company expects would be financed through approximately $72.0 million of partner capital contributions (consisting of $36.0 million in cash from the Company and land with a value of $36.0 million from Ashton Park) and approximately $122.3 million of debt financing through a construction lender that has not yet been determined. Construction is scheduled to commence during the fourth quarter of 2013, with a targeted project completion in 2015.

Based upon the facts and circumstances at formation of 4040 Wilson, we determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, we used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and our lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by us, and is accounted for under the equity method of accounting.

In addition, in connection with our development of 4040 Wilson we have agreed to guarantee 100% of any lender mandated recourse. As of September 30, 2013, we had no outstanding guarantees under the 4040 Wilson LLC Venture.

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Two and Six Tower Bridge Exchange Transaction

On June 19, 2013, we acquired, from an unaffiliated third party, the third party's ownership interest in Six Tower Bridge real estate venture through a nonmonetary exchange for our ownership interest in the Two Tower Bridge real estate venture. Six Tower Bridge owns an unencumbered office property in Conshohocken, PA. We previously accounted for our noncontrolling interest in Six Tower Bridge using the equity method. As a result of the exchange transaction we obtained control of the Six Tower Bridge property and our existing equity interest was remeasured at fair value based on the fair value of the underlying property and the distribution provisions of the real estate venture agreement. Accordingly, during 2013, we recorded a gain of approximately $7.8 million, which is reflected in "Gain on remeasurement of investment in real estate venture" on the accompanying statements of operations. Following the acquisition, the Class A office property in Conshohocken, PA is wholly owned by us with an unencumbered fair value of $24.5 million. We accounted for this acquisition as a business combination and allocated the fair value as follows: $14.8 million to building, $6.9 million to land, $3.3 million to intangible assets and $0.5 million to below market lease liabilities assumed.

As mentioned above, we exchanged our investment in Two Tower Bridge real estate venture in an nonmonetary transaction with an unaffiliated third party for the third party's interest in the Six Tower Bridge real estate venture. The investment in Two Tower Bridge had a fair value of $3.6 million on the date of the exchange transaction based on the fair value of the venture's equity and distribution provisions of the real estate venture agreement. Based on the fair value and the carrying value for our investment of $(0.1) million, during 2013 we recognized a gain on exchange ofinterests in real estate venturesof $3.7 million.

evo at Cira Centre South Venture (formerly the Grove Venture)

On January 25, 2013, we formed the evo at Cira Centre South Venture, a joint venture among the Company and two unaffiliated third parties: Campus Crest Properties, LLC ("Campus Crest") and HSRE-Campus Crest IXA, LLC ("HSRE"). The evo at Cira Centre South Venture has commenced construction of a 33-story, 850-bed student housing tower located in the University City submarket of Philadelphia, Pennsylvania to be called "evo at Cira Centre South." We and Campus Crest each own a 30% interest in the evo at Cira Centre South Venture and HSRE owns a 40% interest. The evo at Cira Centre South Venture is developing the project on a one-acre land parcel held under a long-term ground lease with a third party lessor. We contributed to the evo at Cira Centre South Venture our tenancy rights under a long-term ground lease, together with associated development rights, at an agreed-upon value of $8.5 million. The total estimated project costs are $158.5 million, which will be financed through partner capital contributions totaling $60.7 million, with the remaining $97.8 million being financed through construction facilities provided by PNC Bank, Capital One, and First Niagara Bank. Construction has already commenced, with a targeted project completion in 2014.

In connection with the development of the evo at Cira Centre South project (as described in Note 4 to the consolidated financial statements), we and Campus Crest have provided, in addition to customary non-recourse carve-out guarantees, a completion and cost overrun guaranty, as well as a payment guaranty, on the construction financing (with our share of the payment guaranty being approximately $23.0 million).

BDN Beacon Venture

On March 26, 2013, we sold our entire 20% ownership interest in an unconsolidated real estate venture known as BDN Beacon Venture LLC (the "Beacon Venture"). The carrying amount of our investment in the Beacon Venture amounted to $17.0 million at the sale date, with our proceeds effectively matching the carrying amount.

From time to time, we provide guarantees and indemnities on behalf of Real Estate Ventures, including environmental indemnities and non-recourse carve-outs under mortgage loans, in connection with both construction and permanent financing. As of September 30, 2013, the Company had guaranteed repayment of approximately $0.6 million of loans on behalf of the PJP VII Real Estate Venture.

We continually assess our portfolio in light of our strategic and economic considerations to determine whether to sell properties in the portfolio. Sales of properties, and determinations to hold properties for sale, may result in an impairment or other loss, and such loss could be material to our statement of operations.

CRITICAL ACCOUNTING POLICIES AND ESTIMATES

Management’s Discussion and Analysis of Financial Condition and Results of Operations discuss our consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States of America. The preparation of these financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities at the date of the financial statements and the reported amounts of revenue and expenses

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during the reporting period. Certain accounting policies are considered to be critical accounting policies, as they require management to make assumptions about matters that are highly uncertain at the time the estimate is made and changes in accounting policies are reasonably likely to occur from period to period. Management bases its estimates and assumptions on historical experience and current economic conditions. On an on-going basis, management evaluates its estimates and assumptions including those related to revenue, impairment of long-lived assets and the allowance for doubtful accounts. Actual results may differ from those estimates and assumptions.

Our Annual Report on Form 10-K for the year ended December 31, 2012 contains a discussion of our critical accounting policies. There have been no significant changes in our critical accounting policies since December 31, 2012. See also Note 2 in our unaudited consolidated financial statements for the three and nine-month periods ended September 30, 2013 set forth herein. Management discusses our critical accounting policies and management’s judgments and estimates with our Audit Committee.

RESULTS OF OPERATIONS

The following discussion is based on our Consolidated Financial Statements for the three and nine-month periods ended September 30, 2013 and 2012. We believe that presentation of our consolidated financial information, without a breakdown by segment, will effectively present important information useful to our investors.

Net operating income (“NOI”), as presented in the comparative analysis below is defined as total revenue less property operating expenses, real estate taxes and third party management expenses. Property operating expenses that are included in determining NOI consist of costs that are necessary and allocable to our operating properties such as utilities, property-level salaries, repairs and maintenance, property insurance, management fees and bad debt expense. General and administrative expenses that are not reflected in NOI primarily consist of corporate-level salaries, amortization of share based awards to our executives and employees and professional fees that we incur as part of corporate office management. NOI is a non-GAAP financial measure that we use internally to evaluate the operating performance of our real estate assets by segment, as presented in Note 16 to the consolidated financial statements, and of our business as a whole. We believe NOI provides useful information to investors regarding our financial condition and results of operations because it reflects only those income and expense items that are incurred at the property level. While NOI is a relevant and widely used measure of operating performance of real estate investment trusts, it does not represent cash flow from operations or net income as defined by GAAP and should not be considered as an alternative to those measures in evaluating our liquidity or operating performance. NOI also does not reflect general and administrative expenses, interest expenses, real estate impairment losses, depreciation and amortization costs, capital expenditures and leasing costs. Trends in development and construction activities that could materially impact our results from operations are also not included in NOI. We believe that net income, as defined by GAAP, is the most appropriate earnings measure. See Note 16 to the Consolidated Financial Statements for a reconciliation of consolidated NOI to our consolidated net income.

Comparison of the Three-Month Periods Ended September 30, 2013 and September 30, 2012

The table below shows selected operating information for the “Same Store Property Portfolio” and the “Total Portfolio.” The Same Store Property Portfolio consists of 203 properties containing an aggregate of approximately 23.1 million net rentable square feet, and represents properties that we owned for the entire three-month periods ended September 30, 2013 and 2012. The Same Store Property Portfolio includes properties acquired or placed in service on or prior to January 1, 2012 and owned through September 30, 2013. The Total Portfolio includes the effects of other properties that were either placed into service, acquired or redeveloped after January 1, 2012 or disposed prior to September 30, 2013. A property is excluded from our Same Store Property Portfolio and moved into the redevelopment column in the period that we determine that a redevelopment would be the best use of the asset, and when said asset is taken out of service or is undergoing re-entitlement for a future development strategy. This table also includes a reconciliation from the Same Store Property Portfolio to the Total Portfolio net income (i.e., all properties owned by us during the three-month periods ended September 30, 2013 and 2012) by providing information for the properties which were acquired, placed into service, under development or redevelopment and administrative/elimination information for the three-month periods ended September 30, 2013 and 2012.

The Total Portfolio net income presented in the table is equal to the net income of the Parent Company and the Operating Partnership.

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Comparison of three-months ended September 30, 2013 to the three-months ended September 30, 2012

	Same Store Property Portfolio									Recently Completed/Acquired Properties (a)					Development/Redevelopment Properties (b)						Other (Eliminations) (c)						Total Portfolio
(dollars in thousands)	2013			2012			Increase/ (Decrease)			2013			2012		2013			2012			2013			2012			2013			2012			Increase/ (Decrease)
Revenue:
Cash rents	$	106,768		$	102,930		$	3,838		$	1,191		$	—	$	2,379		170			$	(760	)	$	(690	)	$	109,578		$	102,410		$	7,168
Straight-line rents	4,348			4,369			(21		)	94			—		644			303			—			2			5,086			4,674			412
Above/below market rent amortization	1,507			1,574			(67		)	60			—		248			—			—			—			1,815			1,574			241
Total rents	112,623			108,873			3,750			1,345			—		3,271			473			(760		)	(688		)	116,479			108,658			7,821
Tenant reimbursements	19,764			20,042			(278		)	443			—		514			247			(22		)	5			20,699			20,294			405
Termination fees	2,040			931			1,109			—			—		—			—			—			—			2,040			931			1,109
Third party management fees, labor reimbursement and leasing	—			—			—			—			—		—			—			3,263			3,007			3,263			3,007			256
Other	753			1,642			(889		)	—			—		15			1			207			(13		)	975			1,630			(655		)
Total revenue	135,180			131,488			3,692			1,788			—		3,800			721			2,688			2,311			143,456			134,520			8,936
Property operating expenses	40,768			40,979			(211		)	499			—		1,438			340			(2,044		)	(2,536		)	40,661			38,783			1,878
Real estate taxes	13,359			13,111			248			191			—		452			186			188			189			14,190			13,486			704
Third party management expenses	—			—			—			—			—		—			—			1,317			1,298			1,317			1,298			19
Net operating income	81,053			77,398			3,655			1,098			—		1,910			195			3,227			3,360			87,288			80,953			6,335
General & administrative expenses	—			—			—			—			—		(2		)	—			6,438			6,080			6,436			6,080			356
Depreciation and amortization	47,909			46,655			1,254			693			—		1,988			207			23			93			50,613			46,955			3,658
Operating income (loss)	$	33,144		$	30,743		$	2,401		$	405		$	—	$	(76	)	$	(12	)	$	(3,234	)	$	(2,813	)	$	30,239		$	27,918		$	2,321
Number of properties	203			203						2					4						—						209
Square feet	23,082			23,082						252					792						—						24,126
Core Occupancy % (d)	88.2		%	87.1		%				91.7		%			N/A												88.3		%
Other Income (Expense):
Interest income																											268			311			(43		)
Historic tax credit interest income																											11,853			11,840			13
Interest expense																											(30,338		)	(32,620		)	2,282
Interest expense — deferred financing costs																											(1,158		)	(1,218		)	60
Interest expense — financing obligation																											(264		)	(230		)	(34		)
Equity in income of real estate ventures																											714			500			214
Loss on sale of undepreciated real estate sale																											(129		)	—			(129		)
Loss on real estate venture formation																											—			(950		)	950
Loss on early extinguishment of debt																											(11		)	(51		)	40
Income from continuing operations																											11,174			5,500			5,674
Income (loss) from discontinued operations																											(86		)	11,589			(11,675		)
Net income																											$	11,088		$	17,089		$	(6,001	)
Income per common share																											$	0.06		$	0.10		$	(0.04	)

EXPLANATORY NOTES

(a) Results include: Two acquired properties.

(b) Results include: One development, two redevelopments and one re-entitlement property.

(c) Represents certain revenues and expenses at the corporate level as well as various intercompany costs that are eliminated in consolidation and third-party management fees.

(d) Pertains to properties that are part of our core portfolio (i.e. not under development, redevelopment or re-entitlement).

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Total Revenue

Cash rents from the Total Portfolio increased by $7.2 million from the third quarter of 2012 to the third quarter of 2013, primarily attributable to:

• an increase of $3.8 million due to a 2.0% increase in occupancy rates for the third quarter of 2013 compared to the third quarter of 2012.

• an increase of $1.9 million due to our acquisition of 1900 Market Street during the fourth quarter of 2012. This property was 76.6% occupied as of September 30, 2013, with redevelopment expected to commence in the fourth quarter of 2013 in anticipation of the lead tenant's departure in late 2015;

• an increase of $0.6 million related to the acquisition of Six Tower Bridge during the second quarter of 2013;

• an increase of $0.6 million related to the acquisition of 7000 West at Lantana during the fourth quarter of 2012, and;

• an increase of $0.3 million related to a redevelopment property, 660 Germantown Pike, resulting from the expiration of the lead tenant's free rent period during the third quarter of 2013. The redevelopment of this property is expected to be complete during the first quarter of 2014.

Straight-line rents increased by $0.4 million due to a $0.3 million increase related to the lead tenant taking occupancy of a portion of a redevelopment property, 660 Germantown Pike, during the third quarter of 2012. The remaining $0.1 million increase is related to the aforementioned properties we acquired subsequent to September 2012.

Tenant reimbursements increased by $0.4 million, consistent with the increase in operating expenses over the same period. Please see the Property Operating Expenses and Real Estate Taxes explanations below and note that certain costs such as snow removal costs, carry a higher tenant reimbursement percentage.

Termination fees at our Total Portfolio increased by $1.1 million due to timing and volume of tenant move-outs during the third quarter of 2013 when compared to the third quarter of 2012.

Property Operating Expenses

Property operating expenses across our Total Portfolio increased $1.9 million for the third quarter of 2013 compared to the third quarter of 2012, primarily attributable to: (i) an increase of $1.6 million due to additional operating expenses from the aforementioned properties that we acquired and placed into service subsequent to the third quarter of 2012, (ii) an increase of $0.3 million in bad debt expense as a result of leases that were terminated prior to their expiration during the third quarter of 2013, and (iii) an increase of $0.2 million in repairs and maintenance expense, directly attributable to the timing of tenant needs. These increases were offset by a decrease of $0.2 million in various expenses at our same store portfolio, none of which was materially significant.

Real Estate Taxes

Real estate taxes increased by $0.7 million for the third quarter of 2013 compared to the third quarter of 2012, attributable to assessments on the aforementioned properties that we acquired and placed into service subsequent to the third quarter of 2012.

Depreciation and Amortization

Depreciation and amortization expense increased by $3.7 million for the third quarter of 2013 compared to the third quarter of 2012 and is attributable to aforementioned properties we acquired subsequent to September 30, 2012. In addition, depreciation expense increased because of the acceleration of depreciation expense for Plaza 1000 at Main Street. We are in the process of re-entitling this property for residential and mixed-use development, and accordingly, we shortened the useful lives for this building and related assets to the expected demolition date. In addition, a portion of 660 West Germantown Pike was placed into service subsequent to the third quarter of 2012 resulting in additional depreciation expense during the third quarter of 2013.

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Interest Expense

The decrease in interest expense of $2.3 million from the third quarter of 2012 to the third quarter of 2013 is primarily due to the following:

• a decrease of $2.7 million as a result of the repurchases of debt subsequent to the third quarter of 2012, including (i) $6.2 million of our 5.400% Guaranteed Notes due 2014, (ii) $55.5 million of our 7.500% Guaranteed Notes due 2015, and (iii) $100.1 million of our 6.000% Guaranteed Notes due 2016;

• a decrease of $1.2 million in mortgage interest expense which is directly related to the $60.0 million decrease in mortgage indebtedness resulting from the repayment of two mortgage loans during the fourth quarter of 2012;

• a decrease of $0.8 million in Term Loan interest expense which is directly related to repayment of our $150.0 million term loan due 2016 during the fourth quarter of 2012; and,

• a decrease of $0.2 million in swap interest expense which is directly related to us terminating the interest rate swap contracts upon repayment of our $150.0 million term loan due 2016 during the fourth quarter of 2012.

The decrease of $4.9 million in interest expense described above was offset by the following increases in interest expense during the third quarter of 2013 compared to the third quarter of 2012:

• an increase of $2.5 million related to our $250.0 million 3.950% Guaranteed Notes due 2023 issued in the fourth quarter of 2012; and,

• an increase of $0.1 million related to a decrease in capitalized interest.

Loss on Real Estate Venture Formation

Loss on real estate venture formation decreased by $1.0 million from the third quarter of 2012 to the third quarter of 2013 as a result of our termination of an agreement with a third party broker that was entered into upon contributing two properties into a joint venture during December 2011. During the third quarter of 2012, we determined that it was in our best interest to terminate the contract in order to avoid additional commissions and fees on the future joint venture acquisitions, recognizing the fee as an additional cost of forming the real estate venture.

Discontinued Operations

During the third quarter of 2013, we classified one property located in West Chester, Pennsylvania as held for sale. The property was vacant during the third quarter of 2013, and as a result, the property had nominal revenues, operating expenses and depreciation and amortization expense.

During the third quarter of 2012, income from discontinued operations relates to the 26 properties sold by the Company from January 1, 2012 through September 30, 2013 as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. Through the date of sale during the third quarter, the properties had total revenue of $6.1 million, property operating expenses of $2.6 million and depreciation and amortization expense of $1.8 million. We recognized a gain on sale related to 11 flex/office properties located in Exton, Pennsylvania during the three months ended September 30, 2012 for $9.9 million.

Net income

Net income decreased by $6.0 million during the third quarter of 2013 compared to the third quarter of 2012 as a result of the factors described above. Net income is significantly impacted by depreciation of operating properties and amortization of acquired intangibles. These non-cash charges do not directly affect our ability to pay dividends. Amortization of acquired intangibles will continue over the related lease terms or estimated duration of the tenant relationships.

Income per Common Share

Income per share was $0.06 during the third quarter of 2013 as compared to income per share of $0.10 during the third quarter of 2012 as a result of the factors described above.

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Comparison of the Nine-Month Periods Ended September 30, 2013 and September 30, 2012

The table below shows selected operating information for the “Same Store Property Portfolio” and the “Total Portfolio.” The Same Store Property Portfolio consists of 203 properties containing an aggregate of approximately 23.1 million net rentable square feet, and represents properties that we owned for the entire nine-month periods ended September 30, 2013 and 2012. The Same Store Property Portfolio includes properties acquired or placed in service on or prior to January 1, 2012 and owned through September 30, 2013. The Total Portfolio includes the effects of other properties that were either placed into service, acquired or redeveloped after January 1, 2012 or disposed prior to September 30, 2013. A property is excluded from our Same Store Property Portfolio and moved into the redevelopment column in the period that we determine that a redevelopment would be the best use of the asset, and when said asset is taken out of service or is undergoing re-entitlement for a future development strategy. This table also includes a reconciliation from the Same Store Property Portfolio to the Total Portfolio net income (i.e., all properties owned by us during the nine-month periods ended September 30, 2013 and 2012) by providing information for the properties which were acquired, placed into service, under development or redevelopment and administrative/elimination information for the nine-month periods ended September 30, 2013 and 2012.

The Total Portfolio net income presented in the table is equal to the net income of the Parent Company and the Operating Partnership.

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Comparison of nine-months ended September 30, 2013 to the nine-months ended September 30, 2012

	Same Store Property Portfolio									Recently Completed/Acquired Properties (a)					Development/Redevelopment Properties (b)				Other (Eliminations) (c)						Total Portfolio
(dollars in thousands)	2013			2012			Increase/ (Decrease)			2013			2012		2013		2012		2013			2012			2013			2012			Increase/ (Decrease)
Revenue:
Cash rents	$	319,232		$	307,743		$	11,489		$	2,406		$	—	$	6,593	500		$	(2,130	)	$	(2,058	)	$	326,101		$	306,185		$	19,916
Straight-line rents	13,877			16,327			(2,450		)	256			—		2,056		317		1			7			16,190			16,651			(461		)
Above/below market rent amortization	4,492			4,526			(34		)	159			—		738		—		—			—			5,389			4,526			863
Total rents	337,601			328,596			9,005			2,821			—		9,387		817		(2,129		)	(2,051		)	347,680			327,362			20,318
Tenant reimbursements	58,074			56,502			1,572			1,161			—		1,409		670		(29		)	7			60,615			57,179			3,436
Termination fees	2,946			2,522			424			—			—		—		—		—			—			2,946			2,522			424
Third party management fees, labor reimbursement and leasing	—			—			—			—			—		—		—		9,652			9,021			9,652			9,021			631
Other	2,331			3,875			(1,544		)	1			—		149		11		824			143			3,305			4,029			(724		)
Total revenue	400,952			391,495			9,457			3,983			—		10,945		1,498		8,318			7,120			424,198			400,113			24,085
Property operating expenses	120,466			119,342			1,124			883			—		3,993		980		(5,820		)	(7,361		)	119,522			112,961			6,561
Real estate taxes	40,165			39,406			759			544			—		1,468		409		529			615			42,706			40,430			2,276
Third party management expenses	—			—			—			—			—		—		—		4,105			3,812			4,105			3,812			293
Net Operating Income	240,321			232,747			7,574			2,556			—		5,484		109		9,504			10,054			257,865			242,910			14,955
General & administrative expenses	—			(6		)	6			181			—		1		—		20,140			18,215			20,322			18,209			2,113
Depreciation and amortization	138,895			141,314			(2,419		)	1,397			—		5,399		557		3,732			391			149,423			142,262			7,161
Operating Income (loss)	$	101,426		$	91,439		$	9,987		$	978		$	—	$	84	(448	)	$	(14,368	)	$	(8,552	)	$	88,120		$	82,439		$	5,681
Number of properties	203			203						2					4				—						209
Square feet	23,082			23,082						252					792				—						24,126
Occupancy % (d)	88.2		%	87.1		%				91.7		%			N/A										88.3		%
Other Income (Expense):
Interest income																									448			2,631			(2,183		)
Historic tax credit interest income																									11,853			11,840			13
Interest expense																									(91,689		)	(99,745		)	8,056
Interest expense — deferred financing costs																									(3,502		)	(3,790		)	288
Interest expense — financing obligation																									(693		)	(608		)	(85		)
Equity in income of real estate ventures																									3,757			1,382			2,375
Gain from remeasurement of investment in a real estate venture																									7,847			—			7,847
Net gain on real estate venture transactions																									3,683			—			3,683
Net loss on sale of undepreciated real estate sale																									(129		)	—			(129		)
Loss on real estate venture formation																									—			(950		)	950
Loss on early extinguishment of debt																									(1,127		)	(1,549		)	422
Income (loss) from continuing operations																									18,568			(8,350		)	$	26,918
Income from discontinued operations																									3,619			41,577			(37,958		)
Net income																									$	22,187		$	33,227		$	(11,040	)
Income per common share																									$	0.11		$	0.16		$	(0.05	)

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EXPLANATORY NOTES

(a) Results include: Two acquired properties.

(b) Results include: One development, two redevelopments and one re-entitlement property.

(c) Represents certain revenues and expenses at the corporate level as well as various intercompany costs that are eliminated in consolidation and third-party management fees.

(d) Pertains to properties that are part of our core portfolio (i.e. not under development, redevelopment or re-entitlement).

Total Revenue

Cash rents from the Total Portfolio increased by $19.9 million from the nine months ended September 30, 2012 to the nine months ended September 30, 2013, primarily reflecting:

• an increase of $11.5 million due to a 1.9% increase in occupancy rates from the nine-month period ended September 30, 2012 to the nine-month period ended September 30, 2013;

• an increase of $5.8 million due to our acquisition of 1900 Market Street during the fourth quarter of 2012. This property was 76.6% occupied as of September 30, 2013, with redevelopment expected to commence in the fourth quarter of 2013 in anticipation of the lead tenant's departure in late 2015;

• an increase of $1.7 million related to the acquisition of 7000 West at Lantana during the fourth quarter of 2012;

• an increase of $0.6 million related to the acquisition of Six Tower Bridge during the second quarter of 2013; and,

• an increase of $0.3 million related to a redevelopment property, 660 Germantown Pike, resulting from the expiration of the lead tenant's free rent period during the third quarter of 2013. The redevelopment of this property is expected to be complete during the first quarter of 2014.

Straight-line rents decreased by $0.5 million during the nine-month period ended September 30, 2013 compared to the nine-month period ended September 30, 2012 due to a $2.4 million decrease from free rent converting to cash subsequent to the third quarter of 2012 at our same store properties. This decrease was offset by an increase of $1.6 million related to a tenant taking occupancy of a portion of a redevelopment property, 660 Germantown Pike, during the third quarter of 2012. In addition straight-line rents increased $0.3 million related to the acquisitions of Six Tower Bridge, 7000 West at Lantana and 1900 Market Street.

Tenant reimbursements increased by $3.4 million consistent with the increase in operating expenses over the same period. Please see the Property Operating Expenses and Real Estate Taxes explanations below and note that certain costs, such as snow removal costs, carry a higher tenant reimbursement percentage.

Property Operating Expenses

Property operating expenses across our Total Portfolio increased by $6.6 million from the nine months ended September 30, 2012 to the nine months ended September 30, 2013 mainly due to $3.9 million of additional expenses from the aforementioned properties that we acquired and placed in service during and subsequent to 2012. The remaining increase is attributable to the following, (i) an increase of $2.3 million in repairs and maintenance expense, directly attributable to the timing of tenant needs, (ii) an increase of $0.4 million in payroll expenses, and (iii) an increase of $0.2 million in bad debt expense related to early tenant move-outs. These increases were offset by decreases in various expenses at our same store portfolio, none of which was materially significant.

Real Estate Taxes

Real estate taxes increased by $2.3 million mainly due to the aforementioned properties acquired and placed into service subsequent to the third quarter of 2012.

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General and Administrative Expenses

General and administrative expenses increased $2.1 million from the nine-month period ended September 30, 2012 to the nine-month period ended September 30, 2013, mainly attributable to the following:

• an increase in the amortization of performance-based compensation of $1.9 million. This increase is due to the fact that certain of our executive personnel meet qualifying retirement conditions during 2013, causing an acceleration of their associated performance based compensation to fully vest, and;

• an increase of $0.2 million related to acquisition costs incurred.

Depreciation and Amortization

Depreciation and amortization increased by $7.2 million for the nine-month period ended September 30, 2013 compared to the nine-month period ended September 30, 2012 and is attributable to a $5.3 million increase in depreciation expense for Plaza 1000 at Main Street and 6 East Clementon. We are in the process of re-entitling these properties for residential and mixed-use development, and accordingly, we shortened the useful lives for each of these buildings to the expected demolition date. An additional increase of $4.3 million is related to the aforementioned properties that we acquired and placed in service subsequent to September 30, 2012. These increases were offset by a decrease of $2.4 million as a result of retiring assets at our same store portfolio.

Interest Income

Interest income decreased by $2.2 million from the nine-month period ended September 30, 2012 to the nine-month period ended September 30, 2013 due to the recognition of $1.0 million of accrued interest income related to the payoff of the Trenton note receivable during second quarter of 2012. The installment sales method was used to account for the transaction as a result of the associated note receivable, and therefore interest income was recognized on a cash basis. We recognized all of the interest income accrued through the second quarter of 2012 upon receipt of payment from the borrower. The remaining decrease of $1.2 million is due to a decrease in interest income earned on investments in available-for-sale securities that were outstanding during the nine-month period ended September 30, 2012. Interest income earned during the nine-month period ended September 30, 2013 primarily represents interest earned on our available operating cash balances ($185.5 million as of September 30, 2013).

Interest Expense

The decrease in interest expense of $8.1 million is primarily due to the following:

• a decrease of $8.0 million as a result of the repurchases of debt subsequent to the third quarter of 2012, including (i) $6.2 million of our 5.400% Guaranteed Notes due 2014, (ii) $55.5 million of our 7.500% Guaranteed Notes due 2015, and (iii) $100.1 million of our 6.000% Guaranteed Notes due 2016;

• a decrease of $3.8 million in mortgage interest expense which is directly related to the $60.0 million decrease resulting from the repayment of two mortgage loans during the fourth quarter of 2012;

• a decrease of $2.2 million related to our $151.5 million 5.400% Guaranteed Notes that matured and were repaid in full during April 2012;

• a decrease of $1.3 million in Term Loan interest expense which is directly related to repayment of our $150.0 million term loan due 2016 during the fourth quarter of 2012;

• a decrease in interest expense of $0.2 million related to our variable rate unsecured debt that is swapped to fixed interest rates; and,

• a decrease in our trust indenture interest of $0.1 million.

The decrease of $15.6 million in interest expense described above was offset by an increase of $7.5 million related to our $250.0 million 3.950% Guaranteed Notes due 2023 issued in the fourth quarter of 2012.

Equity in Income of Real Estate Ventures

The increase in equity in income of real estate ventures of $2.4 million from the nine-month period ended September 30, 2012 to the nine-month period ended September 30, 2013 is attributable to the following, (i) an increase of $0.9 million in preferred return income as a result of additional equity contributions made to the One and Two Commerce Square Real Estate Ventures subsequent to the third quarter of 2012, (ii) an increase of $0.9 million as a result of recognizing losses during 2012 related to the Two and Six Tower Bridge ventures. We sold our interest in each venture during the second quarter of 2013 and (iii) an increase of $0.7 million from the BDN AI Venture because of acquisition costs the venture incurred during the nine months ended September 2012

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related to the purchase of three operating properties. These increases were offset by a decrease of $0.3 million as a result of selling our interest in the Beacon Venture during the nine-month period ended September 30, 2013.

Gain on Remeasurement of an Investment in a Real Estate Venture

Gain on remeasurement of an investment in a real estate venture increased by $7.8 million for the nine months ended September 30, 2013 with no comparable gains recognized during the nine-month period ended September 30, 2012. This gain resulted from the Company taking control of Six Tower Bridge during the nine months ended September 30, 2013 which required the remeasurement at fair value of our existing equity interest in Six Tower Bridge (discussed in Footnote 4 of our consolidated financial statements).

Net Gain on Real Estate Venture Transactions

The $3.7 million increase in gain on real estate venture transactions is the result of the exchange of our remaining ownership in the Two Tower Bridge Venture for the remaining ownership interest in the Six Tower Bridge Venture, as discussed above in Footnote 4 of our consolidated financial statements.

Loss on Real Estate Venture Formation

Loss on real estate venture formation decreased by $1.0 million from the nine months ended September 30, 2012 to the nine months ended September 30, 2013 as a result of our termination of an agreement with a third party broker that was entered into upon contributing two properties into a joint venture during December 2011. During the third quarter of 2012, we determined that it was in our best interest to terminate the contract in order to avoid additional commissions and fees on the future joint venture acquisitions, recognizing the fee as an additional cost of forming the real estate venture.

Loss on Early Extinguishment of Debt

During the nine-month period ended September 30, 2013, we repurchased (i) $6.2 million of our 5.400% Guaranteed Notes due 2014, (ii) $5.2 million of our 7.500% Guaranteed Notes due 2015, and (iii) $0.5 million of our 6.000% Guaranteed Notes due 2016, which resulted in a net loss on early extinguishment of debt of $1.1 million.

During the nine-month period ended September 30, 2012, we repurchased (i) $4.3 million of our 5.400% Guaranteed Notes due 2014, (ii) $10.5 million of our 7.500% Guaranteed Notes due 2015, and (iii) $0.3 million of our 5.750% Guaranteed Notes due 2012, which resulted in a net loss on early extinguishment of debt of $1.5 million.

Discontinued Operations

During the nine-month period ended September 30, 2013, we sold a portfolio of eight office properties located in Lawrenceville, New Jersey, one property located in San Diego, California, one property located in Carlsbad, California, one property located in Malvern, Pennsylvania and one property located in Exton, Pennsylvania. Through the date of sale during the nine-month period ending September 30, 2013, the properties had total revenues of $4.6 million, property operating expenses of $2.2 million and $1.8 million of depreciation and amortization expense. We recognized a net gain on sale related to these transactions of $3.0 million. We classified one property located in West Chester, Pennsylvania as held for sale. The property was vacant during the nine-month period ended September 30, 2013 and as a result, the property had nominal revenues, $0.2 million of operating expenses and nominal depreciation and amortization expense.

During the nine-month period ended September 30, 2012, income from discontinued operations relates to the 26 properties sold by the Company from January 1, 2012 through September 30, 2013 as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. These properties had total revenues of $24.5 million, property operating expenses of $9.6 million, and depreciation and amortization expense of $8.1 million through their respective dates of sale. In addition, we recognized a deferred gain related to two properties located in Trenton, New Jersey that were sold during the fourth quarter of 2009. The gain was deferred as a result of a note receivable that we held from the buyer in the amount of $22.5 million. The note receivable and accrued interest was paid in full during the second quarter of 2012, prior to its maturity date of October 2016. We recognized a net gain on sale related to these transactions of $34.8 million during the nine months ended September 30, 2012.

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Net income

Net income decreased by $11.0 million during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012 as a result of the factors described above. Net income is significantly impacted by depreciation of operating properties and amortization of acquired intangibles. These non-cash charges do not directly affect our ability to pay dividends. Amortization of acquired intangibles will continue over the related lease terms or estimated duration of the tenant relationships.

Income per Common Share

Income per share was $0.11 during the nine months ended September 30, 2013 as compared to income per share of $0.16 during the nine months ended September 30, 2012 as a result of the factors described above.

LIQUIDITY AND CAPITAL RESOURCES OF THE PARENT COMPANY

The Parent Company conducts its business through the Operating Partnership and the Parent Company's only material asset is its ownership of partnership interests in the Operating Partnership. The Parent Company, other than acting as the sole general partner of the Operating Partnership, issues equity from time to time (and contributes the net proceeds of such issuances to the Operating Partnership in exchange for additional equity interests in the Operating Partnership) and guarantees the debt obligations of the Operating Partnership. The Parent Company’s principal funding requirement is the payment of dividends on its common shares and preferred shares. The Parent Company’s source of funding for its dividend payments and other obligations is the distributions it receives from the Operating Partnership.

As of September 30, 2013, the Parent Company owned a 98.8% interest in the Operating Partnership. The remaining interest of approximately 1.2% pertains to common limited partnership interests owned by non-affiliated investors who contributed property to the Operating Partnership in exchange for their interests. As the sole general partner of the Operating Partnership, the Parent Company has full and complete responsibility for the Operating Partnership’s day-to-day operations and management.

As noted above, the Parent Company’s only source of capital (other than proceeds of equity issuances which the Parent Company contributes to the Operating Partnership) is distributions it receives from the Operating Partnership. The Parent Company believes that the Operating Partnership’s sources of working capital, particularly its cash flows from operations and borrowings available under its credit facilities, are adequate for it to make its distribution payments to the Parent Company, which in turn enables the Parent Company to make dividend payments to its shareholders.

The Parent Company receives proceeds from equity issuances from time to time and contributes such proceeds from its equity issuances to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Parent Company’s ability to sell common shares and preferred shares is dependent on, among other things, general market conditions for REITs, market perceptions about the Company as a whole and the current trading price of its shares. The Parent Company regularly analyzes which source of capital is most advantageous to it at any particular point in time.

On April 10, 2013, the Parent Company completed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership intends to continue to use the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

On September 10, 2013, the Parent Company declared a distribution of $0.15 per common share, totaling $23.8 million, which it paid on October 18, 2013 to its shareholders of record as of October 4, 2013. In addition, the Parent Company declared distributions on its Series E Preferred Shares to holders of record as of September 30, 2013. These shares are entitled to a preferential return of 6.90% per annum on the $25.00 per share liquidation preference. Distributions paid on October 15, 2013 to holders of Series E Preferred Shares totaled $1.7 million.

The Parent Company maintains a share repurchase program under which its Board of Trustees has authorized the Parent Company to repurchase common shares from time to time in accordance with the limits set by the Board of Trustees. As of September 30, 2013, there were 539,200 shares available for repurchase under this program. The Parent Company did not repurchase any shares during the nine-month period ended September 30, 2013. The Parent Company’s Board of Trustees has not limited the duration of the program and the program may be terminated at any time.

Together with the Operating Partnership, the Parent Company maintains a shelf registration statement that covers common shares, preferred shares, depositary shares, warrants and unsecured debt securities. Subject to the Company’s ongoing compliance with

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securities laws, and if warranted by market conditions, the Parent Company and the Operating Partnership may offer and sell equity and debt securities from time to time under the shelf registration statement.

The Parent Company unconditionally guarantees the Operating Partnership’s secured and unsecured obligations, which, as of September 30, 2013, amounted to $435.6 million and $1,947.1 million, respectively. If the Operating Partnership were to fail to comply with the covenants and restrictions in its loan agreements and indenture, then the Parent Company would be required to fulfill the Operating Partnership’s commitments under such guarantees. The Parent Company's only material asset, however, is its ownership interest in the Operating Partnership. As of September 30, 2013, the Operating Partnership was in compliance with all of its debt covenant and requirement obligations.

In order to maintain its qualification as a REIT, the Parent Company is required to, among other things, pay dividends to its shareholders amounting to at least 90% of its REIT taxable income. The Parent Company has satisfied and expects to continue to satisfy this requirement.

Overall, the liquidity of the Parent Company is dependent on the Operating Partnership’s ability to make distributions to the Parent Company. However, there can be no assurance that the Operating Partnership’s sources of capital will continue to be available to meet its working capital needs including its ability to make distribution payments to the Parent Company. In cases where the Operating Partnership is faced with working capital problems or would need to raise capital to fund acquisitions and developments, the Parent Company will have to consider alternative sources to increase liquidity, including, among other things, equity or debt, use of its available line of credit and potential sale of properties.

LIQUIDITY AND CAPITAL RESOURCES OF THE OPERATING PARTNERSHIP

General

The Operating Partnership’s principal liquidity needs for the next twelve months are as follows:

• fund normal recurring expenses,

• fund capital expenditures, including capital and tenant improvements and leasing costs,

• fund repayment of certain debt instruments when they mature,

• fund current development and redevelopment costs, and

• fund distributions to the Parent Company.

The Operating Partnership believes that with continued uncertain economic conditions, vacancy rates may increase, effective rental rates on new and renewed leases may decrease and tenant installation costs, including concessions, may increase in most or all of its markets throughout the remainder of 2013 and beyond. As a result, the Operating Partnership’s revenue from the overall reduced demand for office space, and its cash flow could be insufficient to cover increased tenant installation costs over the short-term. If this situation were to occur, the Operating Partnership expects that it would finance cash deficits through borrowings under its unsecured credit facility and other sources of debt and equity financings.

The Operating Partnership believes that its liquidity needs will be satisfied through available cash balances and cash flows generated by operations, financing activities and selective property sales. Rental revenue, expense recoveries from tenants, and other income from operations are its principal sources of cash that it uses to pay operating expenses, debt service, recurring capital expenditures and the minimum distributions required to maintain its REIT qualification. The Operating Partnership seeks to increase cash flows from its properties by maintaining quality standards for its properties that promote high occupancy rates and permit increases in rental rates while reducing tenant turnover and controlling operating expenses. The Operating Partnership’s revenue also includes third-party fees generated by its property management, leasing, development and construction businesses. The Operating Partnership believes that its revenue, together with proceeds from property sales and debt financings, will continue to provide funds for its short-term liquidity needs. However, material changes in its operating or financing activities may adversely affect net cash flows of the Operating Partnership. Reduction in net cash flows would, in turn, adversely affect the Operating Partnership's ability to fund distributions to the Parent Company, pay debt service, and fund tenant improvements and other expenses. In addition, a material adverse change in cash provided by operations could adversely affect the Operating Partnership's compliance with financial performance covenants under its unsecured credit facility, including unsecured term loans and unsecured notes.

In light of the continuing volatility in financial markets and economic uncertainties, it is possible, that one or more lenders under the Operating Partnership's unsecured revolving credit facility could fail to fund a borrowing request of the Operating Partnership. Such an event could adversely affect the Operating Partnership's ability to access funds from its Credit Facility when needed to fund distributions or pay expenses.

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The Operating Partnership uses multiple financing sources to fund its long-term capital needs. When needed, the Operating Partnership uses borrowings under its unsecured credit facility for general business purposes, including to meet debt maturities and to fund distributions to the Parent Company as well as development and acquisition costs and other expenses from time to time as necessary.

The Operating Partnership’s ability to incur additional debt is dependent upon a number of factors, including its credit ratings, the value of its unencumbered assets, its degree of leverage and borrowing restrictions imposed by its lenders. If one or more rating agencies were to downgrade the Operating Partnership's unsecured credit rating, the Operating Partnership's access to the unsecured debt market would be more limited and the interest rate under its unsecured credit facility and unsecured term loans would increase.

As noted above, the ability of the Parent Company to sell equity securities (and contribute the net proceeds to the Operating Partnership) is dependent on, among other things, general market conditions for REITs, market perceptions about the Company and the current trading price of the Parent Company’s shares. The Operating Partnership may also issue its own partnership units as consideration for property acquisitions or as part of financing.

The Operating Partnership also considers sales of selected assets as part of its liquidity and balance sheet management. The Operating Partnership has from time to time used proceeds from asset sales to repay existing indebtedness, provide capital for its development activities and to strengthen its financial condition. There can be no assurance that the Operating Partnership will be able to sell assets at an attractive price to generate additional capital.

Liquidity management is a key priority of management, and the Operating Partnership regularly evaluates financing opportunities to maintain an appropriate balance sheet position. As a result of these dedicated efforts, the Operating Partnership believes that its current balance sheet is in an adequate position at the date of this filing. The Operating Partnership believes it is able and will continue to be able to meet debt maturities and to fund distributions to the Parent Company as well as development and acquisition costs and other expenses from time to time as necessary.

Cash Flows

The following discussion of the Operating Partnership’s cash flows is based on the consolidated statement of cash flows and is not meant to be a comprehensive discussion of the changes in our cash flows for the periods presented.

As of September 30, 2013 and December 31, 2012, the Operating Partnership maintained cash and cash equivalents of $185.5 million and $1.5 million, respectively. The following are the changes in cash flow from its activities for the nine month periods ended September 30, 2013 and September 30, 2012 (in thousands):

Activity	2013		2012
Operating	$	146,228	$	122,145
Investing	16,539		42,865
Financing	21,201		76,196
Net cash flows	$	183,968	$	241,206

The Operating Partnership’s principal source of cash flows is from the operation of its properties. The Operating Partnership does not restate its cash flow for discontinued operations.

Cash provided from operating activities of the Operating Partnership for the nine months ended September 30, 2013 and 2012 were $146.2 million and $122.1 million, respectively. This increase of $24.1 million is primarily attributable to 2012 acquisitions and increased net operating income on the same store property portfolio in the 2013 period as compared to the 2012 period.

The net decrease of $26.3 million in cash from investing activities of the Operating Partnership during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012 is primarily attributable to the following:

• a decrease of $25.0 million of net proceeds from the sale of 14 properties during the nine months ended September 30, 2012. There were 13 property sales during the nine months ended September 30, 2013 (see Note 3 to the consolidated financial statements for details);

• receipt of $23.9 million on a mortgage note receivable during the nine months ended September 30, 2012 compared to receipt of $0.2 million during the nine months ended September 30, 2013;

• an increase of $11.5 million in funds used to acquire operating properties, mainly attributable to the Operating Partnership's acquisition of the 1.8 acre land parcel underlying Three Logan Square during the nine months ended

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September 30, 2013 compared to our acquisition of a development property, 660 West Germantown Pike, during the nine months ended September 30, 2012, and;

• an increase in advances made for purchase of tenant assets, net of repayments of $0.4 million during the nine months ended September 30, 2013, when compared to the nine months ended September 30, 2012.

The decrease in cash from investing activities was partially offset by the following transactions:

• a decrease of $19.6 million of investments in unconsolidated Real Estate Ventures during the nine months ended September 30, 2013, primarily reflecting $26.1 million that was contributed to fund our share of an acquisition of three office properties by the BDN AI Venture, $12.0 million that we contributed to a Real Estate Venture to fund our pro rata share of the repayment of mortgage indebtedness during the nine months ended September 30, 2012, and $9.6 million of contributions to fund our share of One and Two Commerce Square ventures' operations, offset by our contribution pro rata share of capital to fund the evo at Cira Centre South Venture (formerly the Grove Venture) and our contribution to form 4040 Wilson real estate venture during the nine months ended September 30, 2013;

• an increase of $17.0 million in proceeds from the sale of the Operating Partnership's entire 20% ownership interest in the Real Estate Venture known as "BDN Beacon, LLC Venture" during the nine months ended September 30, 2013, with no comparable activity for the nine months ended September 30, 2012 (see Note 4 to the consolidated financial statements for details);

• a $5.1 millionincrease in capital expenditures related to developments, redevelopments, tenant and building improvements and leasing commissions during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012.

• our receipt of $2.0 million in reimbursement of pre-formation development expenses from a Real Estate Venture during the nine months ended September 30, 2013 with no comparable reimbursements during the nine months ended September 30, 2012; and

• an increase of $0.9 million in cash distributions from a Real Estate Venture during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012, primarily reflecting increased distributions of operating cash flow by the Real Estate Venture known as "BDN AI Venture" during the nine months ended September 30, 2013.

The net decrease of $55.0 million in cash from financing activities during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012 is mainly due to the following:

• receipt of new unsecured term loan funding of $600.0 million during the nine months ended September 30, 2012, with no comparable funding for the nine months ended September 30, 2013; and,

• receipt of $96.2 million proceeds from the issuance of the Parent Company's 6.90% Series E Preferred Shares during the nine months ended September 30, 2012, with no comparable preferred share issuance in the nine months ended September 30, 2013.

The net decrease in cash from financing activities described above was offset by the following:

• receipt of $181.5 million in proceeds from the 12,650,000 common share issuance by the Parent Company during the nine months ended September 30, 2013 with no comparable share issuance during the nine months ended September 30, 2012;

• an increase of $164.5 million in borrowings under the unsecured credit facility during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012;

• redemption of the Parent Company's 7.50% Series C Preferred Shares of $50.2 million during the nine months ended September 30, 2012, with no comparable charges during the nine months ended September 30, 2013;

• a $42.9 milliondecrease in repayments under the unsecured credit facility and mortgage notes payable during the nine months ended September 30, 2013 compared to the nine months ended September 30, 2012;

• repayment of an unsecured term loan of $37.5 million during the nine months ended September 30, 2012, with no comparable repayment during the nine months ended September 30, 2013;

• debt financing cost payments of $8.5 million during the nine months ended September 30, 2012, with nominal costs paid during the nine months ended September 30, 2013;

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• repayment of unsecured notes of $167.8 million during the nine months ended September 30, 2012, with $13.0 million repayments during the nine months ended September 30, 2013;

• a $1.5 million increase in proceeds from the exercise of stock options during the nine month period ended September 30, 2013 compared to the nine month period ended September 30, 2012;

• net settlement of hedge transactions of $0.1 million during the nine months ended September 30, 2012, with no comparable settlements during the nine months ended September 30, 2013, and;

• a increase in distributions paid to the Parent Company's shareholders and on non-controlling interests in the Operating Partnership from $72.7 million during the nine months ended September 30, 2012 to $72.9 million during the nine months ended September 30, 2013.

Capitalization

Indebtedness

During the nine months ended September 30, 2013, we repurchased $11.9 million of our outstanding unsecured notes in a series of transactions which are summarized in the table below (in thousands):

Notes	Repurchase Amount		Principal		Loss			Deferred Financing Amortization
2014 5.400% Notes	$	6,570	$	6,180	$	(401	)	$	7
2015 7.500% Notes	5,843		5,210		(663		)	15
2016 6.000% Notes	573		510		(63		)	1
	$	12,986	$	11,900	$	(1,127	)	$	23

The table below summarizes the Operating Partnership’s indebtedness under its mortgage notes payable, its unsecured notes and its Credit Facility at September 30, 2013 and December 31, 2012:

	September 30, 2013			December 31, 2012
	(dollars in thousands)
Balance:
Fixed rate	$	2,282,643		$	2,302,895
Variable rate — unhedged	100,000			169,000
Total	$	2,382,643		$	2,471,895
Percent of Total Debt:
Fixed rate	95.8		%	93.2		%
Variable rate — unhedged	4.2		%	6.8		%
Total	100		%	100		%
Weighted-average interest rate at period end:
Fixed rate	5.3		%	5.3		%
Variable rate — unhedged	1.9		%	1.9		%
Total	5.1		%	5.1		%

The variable rate debt shown above generally bear interest based on various spreads over a LIBOR term selected by the Operating Partnership.

The Operating Partnership will use Credit Facility borrowings for general business purposes, including the acquisition, development and redevelopment of properties and the repayment of other debt. It has the option to increase the maximum borrowings under the Credit Facility to $800.0 million subject to the absence of any defaults and its ability to obtain additional commitments from its existing or new lenders. The Credit Facility requires the maintenance of financial covenants, including ratios related to minimum net worth, debt to total capitalization and fixed charge coverage and customary non-financial covenants. The Operating Partnership is in compliance with all covenants as of September 30, 2013.

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The indenture under which the Operating Partnership issued its unsecured notes contains financial covenants, including (i) a leverage ratio not to exceed 60%, (ii) a secured debt leverage ratio not to exceed 40%, (iii) a debt service coverage ratio of greater than 1.5 to 1.0 and (iv) an unencumbered asset value of not less than 150% of unsecured debt. The Operating Partnership is in compliance with all covenants as of September 30, 2013.

The Operating Partnership has mortgage loans that are collateralized by certain of its Properties. Payments on mortgage loans are generally due in monthly installments of principal and interest, or interest only. The Operating Partnership intends to refinance or repay its mortgage loans as they mature through the use of proceeds from selective Property sales and secured or unsecured borrowings. However, in the current and expected future economic environment one or more of these sources may not be available on attractive terms or at all.

The charter documents of the Parent Company and Operating Partnership do not limit the amount or form of indebtedness that the Operating Partnership may incur, and its policies on debt incurrence are solely within the discretion of the Parent Company’s Board of Trustees, subject to the financial covenants in the Credit Facility, indenture and other credit agreements.

The Company, from time to time, also provides guarantees and indemnities, including environmental indemnities, in connection with construction and permanent financing both for its own account and on behalf of its Real Estate Ventures. As of September 30, 2013, the Operating Partnership had guaranteed repayment of approximately $0.6 million of loans on behalf of one Real Estate Venture. In connection with our development of evo at Cira Centre South Venture, the Operating Partnership and Campus Crest have each provided, in addition to customary non-recourse carve-out guarantees, a completion and cost overrun guaranty, as well as a payment guaranty, on the construction financing (with the Company's share of the payment guaranty being approximately $23.0 million). In addition, in connection with the Company’s development of the 4040 Wilson it has agreed to guarantee 100% of any lender mandated recourse. As of September 30, 2013, the Company had no outstanding guarantees under 4040 Wilson. The Operating Partnership also provides customary environmental indemnities and completion guarantees in connection with construction and permanent financing both for its own account and on behalf of certain of the Real Estate Ventures.

Equity

On September 10, 2013, the Operating Partnership declared a distribution of $0.15 per common partnership unit, totaling $23.8 million, which was paid on October 18, 2013 to unitholders of record as of October 4, 2013.

On September 10, 2013, the Operating Partnership declared distributions on its Series E-Linked Preferred Mirror Units to holders of record as of September 30, 2013. These units are entitled to a preferential return of 6.90% per annum on the $25.00 per unit liquidation preference. Distributions paid on October 15, 2013 to holders of Series E-Linked Preferred Mirror Units totaled $1.7 million.

On April 10, 2013, the Parent Company completed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership is using the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

Together with the Operating Partnership, the Parent Company maintains a shelf registration statement that covers common shares, preferred shares, depositary shares, warrants and unsecured debt securities. Subject to the Company’s ongoing compliance with securities laws, if warranted by market conditions, the Parent Company and the Operating Partnership may offer and sell equity and debt securities from time to time under the shelf registration statement.

The Parent Company did not purchase any shares under its share repurchase program during the nine-month period ended September 30, 2013 and accordingly, during the nine-month period ended September 30, 2012, the Operating Partnership did not repurchase any units in connection with the Parent Company's share repurchase program.

Short- and Long-Term Liquidity

The Operating Partnership believes that its available cash balances and cash flow from operations are adequate to fund its short-term liquidity requirements, excluding principal payments of maturing debt obligations. Cash flow from operations is generated primarily from rental revenues and operating expense reimbursements from tenants and management services income from providing services to third parties. The Operating Partnership intends to use these funds to meet short-term liquidity needs, which are to fund operating expenses, recurring capital expenditures, tenant allowances, leasing commissions, interest expense and the minimum distributions required to maintain the Parent Company’s REIT qualification under the Internal Revenue Code. The

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Operating Partnership expects to meet short-term scheduled debt maturities through borrowings under the Credit Facility and proceeds from potential asset dispositions. As of September 30, 2013, the Operating Partnership had $1,947.1 million of total unsecured debt and $435.6 million of mortgage debt with $2.9 million of mortgage principal payments scheduled to be repaid through December 31, 2013.

The Operating Partnership expects to meet its long-term liquidity requirements, such as for property acquisitions, development, investments in real estate ventures, scheduled debt maturities, major renovations, expansions and other significant capital improvements, through cash from operations, borrowings under the Credit Facility, additional secured and unsecured indebtedness, the issuance of equity securities, contributions from Real Estate Venture investors and proceeds from asset dispositions.

During the third quarter of 2013, as previously announced in the Form 8-K filed on September 11, 2013, the Operating Partnership entered into an agreement with Parkway Properties, Inc. to acquire 74% of their prospective 75% interests in One and Two Commerce Square, two 41-story office towers located in Philadelphia’s Central Business District in which the Operating Partnership currently holds a 25% interest and Thomas Properties Group Inc. affiliate currently holds a 75% interest. During the fourth quarter of 2013 the Operating Partnership expects to fund the required $69.1 million payment from available cash balances. The purchase of these interests is subject to customary closing conditions and completion of the pending merger between Parkway Properties, Inc and Thomas Properties Group Inc.

Inflation

A majority of the Operating Partnership’s leases provide for tenant reimbursement of real estate taxes and operating expenses either on a triple net basis or over a base amount. In addition, many of its office leases provide for fixed base rent increases. The Operating Partnership believes that inflationary increases in expenses will be partially offset by expense reimbursement and contractual rent increases.

Commitments and Contingencies

The following table outlines the timing of payment requirements related to the Operating Partnership’s contractual commitments as of September 30, 2013:

	Payments by Period (in thousands)
	Total		Less than 1 Year		1-3 Years		3-5 Years		More than 5 Years
Mortgage notes payable (a)	$	435,590	$	11,770	$	197,217	$	40,603	$	186,000
Unsecured term loans	450,000		—		250,000		—		200,000
Unsecured debt (a)	1,497,053		—		543,443		625,000		328,610
Ground leases (b)	290,220		2,265		4,576		4,576		278,803
Development contracts (c)	386		386		—		—		—
Interest expense (d)	527,382		117,763		172,131		95,132		142,356
Other liabilities (e)	15,342		—		—		—		15,342
	$	3,215,973	$	132,184	$	1,167,367	$	765,311	$	1,151,111

(a) Amounts do not include unamortized discounts and/or premiums.

(b) Future minimum rental payments under the terms of all non-cancelable ground leases under which we are the lessee are expensed on a straight-line basis regardless of when payments are due. The table also does not include the future minimum rental payments related to the ground lease in connection with our acquisition of 3020 Market Street in Philadelphia, Pennsylvania. This ground lease is discussed below.

(c) Represents contractual obligations for development projects and does not contemplate all costs expected to be incurred for such developments.

(d) Variable rate debt future interest expense commitments are calculated using September 30, 2013 interest rates.

(e) Other liabilities consists of deferred compensation liability and the interest accretion on the existing transfer tax liability on Two Logan Square in Philadelphia, Pennsylvania (see related discussion below), as of September 30, 2013.

On October 31, 2013 the Operating Partnership determined to proceed with development of the Cira Walnut Tower, which it contemplates as a 47-story office and residential tower at 30^th and Walnut Streets in Philadelphia on a site ground leased from the

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University of Pennsylvania. The Operating Partnership anticipates the office component of the project will cost approximately $236.0 million with the residential component costing approximately $105.0 million for a total project cost of $341.0 million. The Operating Partnership expects Cira Walnut to be ready for initial occupancy during the second quarter of 2016. For additional information please refer to Development Risk within the OVERVIEW section.

The Operating Partnership acquired ground tenancy rights under a long term ground lease agreement related to its acquisition of 3020 Market Street in Philadelphia, Pennsylvania on August 12, 2011. The annual rental payments under this ground lease are equal to a percentage of the NOI generated by the property. The Company has not included the amounts in the table above since such amounts are not fixed or determinable.

One of the land leases for a property provides for contingent rent participation by the lessor in certain capital transactions and net operating cash flows of the property after certain returns are achieved by the Company. Such amounts, if any, will be reflected as contingent rent when incurred. The leases also provide for payment by the Company of certain operating costs relating to the land, primarily real estate taxes. The above schedule of future minimum rental payments does not include any contingent rent amounts or any reimbursed expenses.

As part of the Operating Partnership’s September 2004 acquisition of a portfolio of properties from the Rubenstein Company (which the Operating Partnership refers to as the “TRC acquisition”), the Operating Partnership acquired its interest in Two Logan Square, a 708,844 square foot office building in Philadelphia, primarily through its ownership of a second and third mortgage secured by this property. This property is consolidated as the borrower is a variable interest entity and the Operating Partnership, through its ownership of the second and third mortgages, is the primary beneficiary. The Operating Partnership currently does not expect to take title to Two Logan Square until, at the earliest, September 2019. If the Operating Partnership takes fee title to Two Logan Square upon a foreclosure of its mortgage, the Operating Partnership has agreed to pay an unaffiliated third party that holds a residual interest in the fee owner of this property an amount equal to $2.9 million. On the TRC acquisition date, the Operating Partnership recorded a liability of $0.7 million and this amount will accrete up to $2.9 million through September 2019. As of September 30, 2013, the Operating Partnership has a balance of $1.6 million for this liability on its consolidated balance sheet.

The Operating Partnership was audited by the IRS for its 2004 tax year. The audit concerned the tax treatment of the TRC acquisition in September 2004 in which the Operating Partnership acquired a portfolio of properties through the acquisition of a limited partnership. On December 17, 2010, the Operating Partnership received notice that the IRS proposed an adjustment to the allocation of recourse liabilities allocated to the contributor of the properties. The Operating Partnership appealed the proposed adjustment and during the second quarter of 2013 entered into a settlement agreement with the IRS which will not result in a material liability for the Operating Partnership for federal income taxes. The contributor of partnership interests in the 2004 transaction has agreed not to assert a claim against the Operating Partnership under the tax protection agreement entered into as part of the transaction.

As part of the Operating Partnership’s 2006 Prentiss merger, the 2004 TRC acquisition and several other transactions, it agreed not to sell certain of the properties it acquired in transactions that would trigger taxable income to the former owners. In the case of the TRC acquisition, the Operating Partnership agreed not to sell acquired properties in non-exempt transactions for periods up to 15 years from the date of the TRC acquisition as follows at September 30, 2013: One Rodney Square and 130/150/170 Radnor Financial Center (January, 2015); and One Logan Square, Two Logan Square and Radnor Corporate Center (January, 2020). In the Prentiss acquisition, the Operating Partnership assumed the obligation of Prentiss not to sell Concord Airport Plaza before March, 2018. The Operating Partnership’s agreements generally provide that we may dispose of the subject properties only in transactions that qualify as tax-free exchanges under Section 1031 of the Internal Revenue Code or in other tax deferred transactions. If the Operating Partnership was to sell a restricted property before expiration of the restricted period in a non-exempt transaction, it would be required to make significant payments to the parties who sold the applicable property to the Operating Partnership for tax liabilities attributed to them.

As part of the Operating Partnership’s acquisition of properties from time to time in tax-deferred transactions, it has agreed to provide certain of the prior owners of the acquired properties with the right to guarantee its indebtedness. If the Operating Partnership were to seek to repay the indebtedness guaranteed by the prior owner before the expiration of the applicable agreement, it will be required to provide the prior owner an opportunity to guarantee a qualifying replacement debt. These debt maintenance agreements may limit its ability to refinance indebtedness on terms that will be favorable to the Operating Partnership.

In connection with the development of the IRS Philadelphia Campus and the Cira South Garage, during 2008, the Operating Partnership entered into a historic tax credit and new markets tax credit arrangement, respectively. The Operating Partnership is required to be in compliance with various laws, regulations and contractual provisions that apply to its historic and new market tax credit arrangements. Non-compliance with applicable requirements could result in projected tax benefits not being realized and therefore, require a refund to USB or a reduction of investor capital contributions, which are reported as deferred income in the Operating Partnership’s consolidated balance sheet, until such time as its obligation to deliver tax benefits is relieved. The

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remaining compliance periods for its tax credit arrangements runs through 2015. The Operating Partnership does not anticipate that any material refunds or reductions of investor capital contributions will be required in connection with these arrangements.

The Operating Partnership invests in properties and regularly incurs capital expenditures in the ordinary course of its business to maintain the properties. The Operating Partnership believes that such expenditures enhance its competitiveness. The Operating Partnership also enters into construction, utility and service contracts in the ordinary course of its business which may extend beyond one year. These contracts typically provide for cancellation with insignificant or no cancellation penalties.

Interest Rate Risk and Sensitivity Analysis

The analysis below presents the sensitivity of the market value of the Operating Partnership’s financial instruments to selected changes in market rates. The range of changes chosen reflects its view of changes which are reasonably possible over a one-year period. Market values are the present value of projected future cash flows based on the market rates chosen.

The Operating Partnership’s financial instruments consist of both fixed and variable rate debt. As of September 30, 2013, its consolidated debt consisted of $435.6 million of mortgage loans and $1,418.4 million of unsecured notes, all of which are fixed rate borrowings. We also have variable rate debt consisting of $78.6 million in trust preferred securities and $450.0 million of unsecured term loans all of which are swapped to fixed, except for $100.0 million of unsecured term loans which bear interest at a variable rate. All financial instruments were entered into for other than trading purposes and the net market value of these financial instruments is referred to as the net financial position. Changes in interest rates have different impacts on the fixed and variable rate portions of our debt portfolio. A change in interest rates on the fixed portion of the debt portfolio impacts the net financial instrument position, but has no impact on interest incurred or cash flows. A change in interest rates on the variable portion of the debt portfolio impacts the interest incurred and cash flows, but does not impact the net financial instrument position.

If market rates of interest increase by 100 basis points, the fair value of the Operating Partnership’s outstanding fixed-rate mortgage debt would decrease by approximately $23.1 million. If market rates of interest decrease by 100 basis points, the fair value of its outstanding fixed-rate mortgage debt would increase by approximately $25.3 million.

As of September 30, 2013, based on prevailing interest rates and credit spreads, the fair value of the Operating Partnership’s $1,418.4 million of unsecured notes was $1,499.2 million. For sensitivity purposes, a 100 basis point change in the discount rate equates to a change in the total fair value of the Operating Partnership’s debt of approximately $14.1 million at September 30, 2013.

From time to time or as the need arises, the Operating Partnership uses derivative instruments to manage interest rate risk exposures and not for speculative purposes. The total carrying value of the Operating Partnership’s variable rate debt (including variable swapped to fixed) was approximately $528.6 million and $597.6 million at September 30, 2013 and December 31, 2012, respectively. The total fair value of the Operating Partnership’s debt was approximately $526.7 million and $595.7 million at September 30, 2013 and December 31, 2012, respectively. For sensitivity purposes, if market rates of interest increase by 100 basis points the fair value of its variable rate debt would decrease by approximately $7.1 million at September 30, 2013. If market rates of interest decrease by 100 basis points the fair value of its outstanding variable rate debt would increase by approximately $3.4 million. A 100 basis point change in the market rate of interest equates to a change in the total fair value of its debt of approximately $1.7 million at December 31, 2012.

At September 30, 2013, the Operating Partnership’s outstanding variable rate debt based on LIBOR totaled approximately $528.6 million, of which $100.0 million remained variable, with the remaining $428.6 million being swapped to fixed. At September 30, 2013, the interest rate on the Operating Partnership's variable rate debt was approximately 1.9%. If market interest rates on its variable rate debt were to change by 100 basis points, total interest expense would have changed by approximately $0.3 million for the quarter ended September 30, 2013.

These amounts were determined solely by considering the impact of hypothetical interest rates on the Operating Partnership’s financial instruments. Due to the uncertainty of specific actions it may undertake to minimize possible effects of market interest rate increases, this analysis assumes no changes in its financial structure.

Funds from Operations (FFO)

Pursuant to the revised definition of FFO adopted by the Board of Governors of the National Association of Real Estate Investment Trusts (“NAREIT”), we calculate FFO by adjusting net income/(loss) attributable to common unit holders (computed in accordance with GAAP) for gains (or losses) from sales of properties, impairment losses on depreciable consolidated real estate, impairment losses on investments in unconsolidated Real Estate Ventures driven by a measurable decrease in the fair value of depreciable real estate held by the unconsolidated Real Estate Ventures, real estate related depreciation and amortization, and after similar

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adjustments for unconsolidated real estate ventures. FFO is a non-GAAP financial measure. The Operating Partnership believes that the use of FFO combined with the required U.S. GAAP presentations, has been beneficial in improving the understanding of operating results of REITs among the investing public and making comparisons of REITs’ operating results more meaningful. The Operating Partnership considers FFO to be a useful measure for reviewing comparative operating and financial performance because, by excluding gains or losses related to sales of previously depreciated operating real estate assets and real estate depreciation and amortization, FFO can help the investing public compare the operating performance of a company’s real estate between periods or as compared to other companies. The Operating Partnership’s computation of FFO may not be comparable to FFO reported by other REITs or real estate companies that do not define the term in accordance with the current NAREIT definition or that interpret the current NAREIT definition differently.

The Operating Partnership considers net income, as defined by U.S. GAAP, to be the most comparable earnings measure to FFO. While FFO and FFO per unit are relevant and widely used measures of operating performance of REITs, FFO does not represent cash flow from operations or net income as defined by U.S. GAAP and should not be considered as alternatives to those measures in evaluating the company’s liquidity or operating performance. The Operating Partnership believes that to further understand our performance, FFO should be compared with its reported net income/(loss) attributable to common unit holders and considered in addition to cash flows in accordance with GAAP, as presented in our consolidated financial statements.

The following table presents a reconciliation of net income (loss) attributable to common unit holders to FFO for the three-month and nine-month periods ended September 30, 2013 and 2012:

	Three-month periods ended						Nine-month periods ended
	September 30,						September 30,
	2013			2012			2013				2012
	(amounts in thousands, except share information)
Net income attributable to common unitholders	$	9,278		$	14,209		$	16,734			$	23,019
Add (deduct):
Amount allocated to unvested restricted unitholders	85			95			278				286
Loss on real estate venture formation	—			950			—				950
Net loss (gain) on disposition of discontinued operations	16			(9,940		)	(3,029		)		(34,774		)
Net gain on real estate venture transactions	—			—			(3,683		)		—
Gain from remeasurement of investment in a real estate venture	—			—			(7,847		)		—
Depreciation and amortization:
Real property — continuing operations	41,516			37,846			121,911				111,898
Leasing costs including acquired intangibles — continuing operations	9,061			9,067			27,410				30,164
Real property — discontinued operations	17			1,782			1,766				7,814
Leasing costs including acquired intangibles — discontinued operations	1			6			3			0.003	291
Company’s share of unconsolidated real estate ventures	3,293			3,971			10,676				10,528
Funds from operations	$	63,267		$	57,986		$	164,219			$	150,176
Funds from operations allocable to unvested restricted shareholders	(227		)	(254		)	(662		)		(769		)
Funds from operations available to common unit holders (FFO)	$	63,040		$	57,732		$	163,557			$	149,407
Weighted-average shares/units outstanding — fully diluted	159,755,821			146,785,731			154,940,454				146,408,921

Item 3. Quantitative and Qualitative Disclosures about Market Risk

Market risk is the exposure to loss resulting from changes in interest rates, commodity prices and equity prices. In pursuing the Company’s business plan, the primary market risk to which it is exposed is interest rate risk. Changes in the general level of interest rates prevailing in the financial markets may affect the spread between the Company’s yield on invested assets and cost of funds and, in turn, the Company’s ability to make distributions or payments to its shareholders. While the Company has not experienced any significant credit losses, in the event of a significant rising interest rate environment and/or continued economic slowdown, defaults could increase and result in losses to the Company which would adversely affect its operating results and liquidity.

See “Interest Rate Risk and Sensitivity Analysis” in Item 2 above.

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Item 4. Controls and Procedures

Controls and Procedures (Parent Company)

(a) Evaluation of disclosure controls and procedures. Under the supervision and with the participation of its management, including its principal executive officer and principal financial officer, the Parent Company conducted an evaluation of its disclosure controls and procedures, as such term is defined under Rule 13a-15(e) promulgated under the Securities Exchange Act of 1934, as amended (the Exchange Act), as of the end of the period covered by this quarterly report. Based on this evaluation, the Parent Company’s principal executive officer and principal financial officer have concluded that the Parent Company’s disclosure controls and procedures are effective as of the end of the period covered by this quarterly report.

(b) Changes in internal control over financial reporting. There was no change in the Parent Company’s internal control over financial reporting that occurred during the period covered by this quarterly report that has materially affected, or is reasonably likely to materially affect, the Parent Company’s internal control over financial reporting.

Controls and Procedures (Operating Partnership)

(a) Evaluation of disclosure controls and procedures. Under the supervision and with the participation of its management, including its principal executive officer and principal financial officer, the Operating Partnership conducted an evaluation of its disclosure controls and procedures, as such term is defined under Rule 13a-15(e) promulgated under the Exchange Act as of the end of the period covered by this quarterly report. Based on this evaluation, the Operating Partnership’s principal executive officer and principal financial officer have concluded that the Operating Partnership’s disclosure controls and procedures are effective as of the end of the period covered by this quarterly report.

(b) Changes in internal control over financial reporting. There was no change in the Operating Partnership’s internal control over financial reporting that occurred during the period covered by this quarterly report that has materially affected, or is reasonably likely to materially affect, the Operating Partnership’s internal control over financial reporting.

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Part II. OTHER INFORMATION

Item 1. Legal Proceedings

None.

Item 1A. Risk Factors

There has been no material change to the risk factors previously disclosed by us in our Annual Report on Form 10-K for the fiscal year ended December 31, 2012.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

The following table summarizes the share repurchases during the nine-month period ended September 30, 2013:

	Total Number of Shares Purchased (a)	Average Price Paid Per Share		Purchased as Part of Publicly Announced Plans or Programs	Shares that May Yet Be Purchased Under the Plans or Programs (b)
2013:
January	1,374	$	12.76	—	539,200
February	16,728	12.96		—	539,200
March	16,028	14.01		—	539,200
April	54,953	14.90		—	539,200
May	—	—		—	539,200
June	—	—		—	539,200
July	—	—		—	539,200
August	—	—		—	539,200
September	—	—		—	539,200
Total	89,083			—

(a) Represents common shares surrendered by employees to the Company to satisfy such employees' tax withholding obligations in connection with the vesting of restricted common shares.

(b) Relates to the remaining share repurchase availability under the Parent Company’s share repurchase program. There is no expiration date on the share repurchase program. The Parent Company’s Board of Trustees initially authorized this program in 1998 and has periodically replenished capacity under the program.

Item 3. Defaults Upon Senior Securities

None.

Item 4. Mine Safety Disclosures

Not applicable.

Item 5. Other Information

None.

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Item 6. Exhibits

(a) Exhibits

31.1	Certification of the Chief Executive Officer of Brandywine Realty Trust pursuant to 13a-14 under the Securities Exchange Act of 1934
31.2	Certification of the Chief Financial Officer of Brandywine Realty Trust pursuant to 13a-14 under the Securities Exchange Act of 1934
31.3	Certification of the Chief Executive Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 13a-14 under the Securities Exchange Act of 1934
31.4	Certification of the Chief Financial Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 13a-14 under the Securities Exchange Act of 1934
32.1	Certification of the Chief Executive Officer of Brandywine Realty Trust pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.2	Certification of the Chief Financial Officer of Brandywine Realty Trust pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.3	Certification of the Chief Executive Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.4	Certification of the Chief Financial Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.1	The following materials from the Quarterly Reports on Form 10-Q of Brandywine Realty Trust and Brandywine Operating Partnership, L.P. for the quarter ended September 30, 2013 formatted in XBRL (eXtensible Business Reporting Language): (i) the Consolidated Balance Sheets, (ii) the Consolidated Statements of Operations, (iii) the Consolidated Statement of Equity, (iv) the Consolidated Statements of Cash Flows, and (v) Notes to Consolidated Financial Statements, detailed tagged and filed herewith.

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SIGNATURES OF REGISTRANT

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

		BRANDYWINE REALTY TRUST (Registrant)
Date:	November 1, 2013	By:	/s/ Gerard H. Sweeney
			Gerard H. Sweeney, President and Chief Executive Officer
			(Principal Executive Officer)
Date:	November 1, 2013	By:	/s/ Howard M. Sipzner
			Howard M. Sipzner, Executive Vice President and Chief Financial Officer
			(Principal Financial Officer)
Date:	November 1, 2013	By:	/s/ Gabriel J. Mainardi
			Gabriel J. Mainardi, Vice President and Chief Accounting Officer
			(Principal Accounting Officer)

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SIGNATURES OF REGISTRANT

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

		BRANDYWINE OPERATING PARTNERSHIP, L.P. (Registrant) BRANDYWINE REALTY TRUST, as general partner
Date:	November 1, 2013	By:	/s/ Gerard H. Sweeney
			Gerard H. Sweeney, President and Chief Executive Officer
			(Principal Executive Officer)
Date:	November 1, 2013	By:	/s/ Howard M. Sipzner
			Howard M. Sipzner, Executive Vice President and Chief Financial Officer
			(Principal Financial Officer)
Date:	November 1, 2013	By:	/s/ Gabriel J. Mainardi
			Gabriel J. Mainardi, Vice President and Chief Accounting Officer
			(Principal Accounting Officer)

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Index to Exhibits

31.1	Certification of the Chief Executive Officer of Brandywine Realty Trust pursuant to 13a-14 under the Securities Exchange Act of 1934
31.2	Certification of the Chief Financial Officer of Brandywine Realty Trust pursuant to 13a-14 under the Securities Exchange Act of 1934
31.3	Certification of the Chief Executive Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 13a-14 under the Securities Exchange Act of 1934
31.4	Certification of the Chief Financial Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 13a-14 under the Securities Exchange Act of 1934
32.1	Certification of the Chief Executive Officer of Brandywine Realty Trust pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.2	Certification of the Chief Financial Officer of Brandywine Realty Trust pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.3	Certification of the Chief Executive Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.4	Certification of the Chief Financial Officer of Brandywine Realty Trust, in its capacity as the general partner of Brandywine Operating Partnership, L.P., pursuant to 18 U.S.C. Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.1	The following materials from the Quarterly Reports on Form 10-Q of Brandywine Realty Trust and Brandywine Operating Partnership, L.P. for the quarter ended June 30, 2013 formatted in XBRL (eXtensible Business Reporting Language): (i) the Consolidated Balance Sheets, (ii) the Consolidated Statements of Operations, (iii) the Consolidated Statement of Equity, (iv) the Consolidated Statements of Cash Flows, and (v) Notes to Consolidated Financial Statements, detailed tagged and filed herewith.

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EX-31.1

Exhibit 31.1

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES

EXCHANGE ACT OF 1934, AS AMENDED

I, Gerard H. Sweeney, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Brandywine Realty Trust;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15(d)-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 1, 2013/s/ Gerard H. Sweeney

Gerard H. Sweeney

President and Chief Executive Officer

EX-31.2

Exhibit 31.2

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES

EXCHANGE ACT OF 1934, AS AMENDED

I, Howard M. Sipzner, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Brandywine Realty Trust;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15(d)-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 1, 2013/s/ Howard M. Sipzner

Howard M. Sipzner

Executive Vice President and Chief Financial Officer

EX-31.3

Exhibit 31.3

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES

EXCHANGE ACT OF 1934, AS AMENDED

I, Gerard H. Sweeney, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Brandywine Operating Partnership, L.P.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15(d)-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 1, 2013/s/ Gerard H. Sweeney

Gerard H. Sweeney

President and Chief Executive Officer

EX-31.4

Exhibit 31.4

CERTIFICATION PURSUANT TO

RULES 13a-14(a) AND 15d-14(a) UNDER THE SECURITIES

EXCHANGE ACT OF 1934, AS AMENDED

I, Howard M. Sipzner, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Brandywine Operating Partnership, L.P.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant's other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15(d)-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's auditors and the audit committee of the registrant's board of directors (or persons performing the equivalent functions):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant's ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date: November 1, 2013/s/ Howard M. Sipzner

Howard M. Sipzner

Executive Vice President and Chief Financial Officer

EX-32.1

Exhibit 32.1

RULE 13(a)-14(b) CERTIFICATION

PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002*

In connection with the Quarterly Report of Brandywine Realty Trust (the “Company”) on Form 10-Q for the quarter ended September 30, 2013 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Gerard H. Sweeney, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Gerard H. Sweeney

Gerard H. Sweeney

President and Chief Executive Officer

Date: November 1, 2013

* A signed original of this written statement required by Section 906 has been provided to Brandywine Realty Trust and will be retained by Brandywine Realty Trust and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.2

Exhibit 32.2

RULE 13(a)-14(b) CERTIFICATION

PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002*

In connection with the Quarterly Report of Brandywine Realty Trust (the “Company”) on Form 10-Q for the quarter ended September 30, 2013 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Howard M. Sipzner, Executive Vice President and Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Howard M. Sipzner

Howard M. Sipzner

Executive Vice President and Chief Financial Officer

Date: November 1, 2013

* A signed original of this written statement required by Section 906 has been provided to Brandywine Realty Trust and will be retained by Brandywine Realty Trust and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.3

Exhibit 32.3

RULE 13(a)-14(b) CERTIFICATION

PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002*

In connection with the Quarterly Report of Brandywine Operating Partnership, L.P. (the “Partnership”) on Form 10-Q for the quarter ended September 30, 2013 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Gerard H. Sweeney, President and Chief Executive Officer of Brandywine Realty Trust, the Partnership's sole general partner, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Gerard H. Sweeney

Gerard H. Sweeney

President and Chief Executive Officer

Date: November 1, 2013

* A signed original of this written statement required by Section 906 has been provided to Brandywine Realty Trust and will be retained by Brandywine Realty Trust and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.4

Exhibit 32.4

RULE 13(a)-14(b) CERTIFICATION

PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002*

In connection with the Quarterly Report of Brandywine Operating Partnership, L.P. (the “Partnership”) on Form 10-Q for the quarter ended September 30, 2013 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Howard M. Sipzner, Executive Vice President and Chief Financial Officer of Brandywine Realty Trust, the Partnership's sole general partner, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d), as applicable, of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Howard M. Sipzner

Howard M. Sipzner

Executive Vice President and Chief Financial Officer

Date: November 1, 2013

* A signed original of this written statement required by Section 906 has been provided to Brandywine Realty Trust and will be retained by Brandywine Realty Trust and furnished to the Securities and Exchange Commission or its staff upon request.

XML

Commitments and Contingencies Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013 sqft Y	Sep. 30, 2004
Long-term Purchase Commitment [Line Items]
Minimum remaining lease period	16
Maximum remaining lease period	90
Leased Area Of Building	708,844
Business Combination, Future Expected Libaility	$ 2.9
Business Acquisition, Cost of Acquired Entity, Liabilities Incurred	$ 1.6	$ 0.7

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Subsequent Events Subsequent Events (Details) (USD $)	0 Months Ended	9 Months Ended				0 Months Ended
	Apr. 10, 2013	Sep. 30, 2013	Sep. 30, 2012	Oct. 16, 2013 Austin Joint Venture [Member] Properties sqft	Oct. 16, 2013 Brandywine Realty Trust [Member] Austin Joint Venture [Member]	Oct. 16, 2013 DRA Advisors LLC [Member] Austin Joint Venture [Member]	Oct. 31, 2013 Residential Real Estate [Member] Cira Walnut Tower [Member] sqft	Oct. 31, 2013 Lesee Tenant 2 [Member] Office Real Estate [Member] Cira Walnut Tower [Member] sqft
Subsequent Event [Line Items]
Number of properties contributed to a joint venture				7
Net rentable square feet				1,398,826			245,000	100,000
Equity Method Investment, Total Value Contributed					$ 330,000,000
Net proceeds from issuance of common shares	181,700,000	181,527,000	0
Equity Method Investment, Ownership Percentage					50.00%	50.00%
Equity Method Investment, Additional Distribution Rights					10.00%
Potential future capital contributions under joint ventures which are not contractually binding					100,000,000
Proceeds from Equity Method Investment, Dividends or Distributions		3,661,000	2,779,000			271,500,000
Non-Recourse Debt						230,600,000
Amount Of Participant Contribution						49,700,000
Equity Method Investments, Closing Costs						1,900,000
Closing Proprations and Lender Holdbacks						6,900,000
Equity method investment, agreement to pay future capital expenditures					5,200,000
Equity Method Investment, Distribution, Net of Initial Funding Agreement						$ 266,300,000

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Fair Value of Financial Instruments

9 Months Ended

Sep. 30, 2013

Fair Value Disclosures [Abstract]

Fair Value Disclosures [Text Block]

FAIR VALUE OF FINANCIAL INSTRUMENTS

The Company determined the fair values disclosed below using available market information and discounted cash flow analyses as of September 30, 2013 and December 31, 2012, respectively. The discount rate used in calculating fair value is the sum of the current risk free rate and the risk premium on the date of measurement of the instruments or obligations. Considerable judgment is necessary to interpret market data and to develop the related estimates of fair value. Accordingly, the estimates presented are not necessarily indicative of the amounts that the Company could realize upon disposition. The use of different estimates and valuation methodologies may have a material effect on the fair value amounts shown. The Company believes that the carrying amounts reflected in the consolidated balance sheets at September 30, 2013 and December 31, 2012 approximate the fair values for cash and cash equivalents, accounts receivable, other assets, accounts payable and accrued expenses.

The following are financial instruments for which the Company’s estimates of fair value differ from the carrying amounts (in thousands):

	September 30, 2013				December 31, 2012
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Mortgage notes payable	$	435,590	$	473,614	$	443,942	$	486,412
Unsecured notes payable	$	1,418,443	$	1,499,166	$	1,430,343	$	1,553,123
Variable rate debt	$	528,610	$	526,693	$	597,610	$	595,693
Notes receivable	$	7,026	$	7,491	$	7,226	$	7,783

The fair value of the Company's unsecured notes payable is categorized at a Level 2 basis (as provided by the accounting standard for Fair Value Measurements and Disclosures). This is because the Company valued these instruments using quoted market prices as of September 30, 2013 and December 31, 2012.

The fair value of the Company's mortgage notes payable, variable rate debt and notes receivable are all categorized at a Level 3 basis (as provided by the accounting standard for Fair Value Measurements and Disclosures). The fair value of the variable rate debt was estimated using a discounted cash flow analysis valuation on the borrowing rates currently available to the Company for loans with similar terms and maturities, as applicable. The fair value of the mortgage debt was determined by discounting the future contractual interest and principal payments by a blended market rate. The fair value of the notes receivable was determined by using the expected cash flows of the notes receivable, and discounting those cash flows using the market rate of interest for mortgage notes with a comparable level of risk. These financial instruments have been categorized as Level 3 because the Company considers the rates used in the valuation techniques to be unobservable inputs.

The only significant unobservable input in the discounted cash flow model is the discount rate. For the fair value of the Company's unsecured notes, the Company uses a discount rate based on the indicative new issue pricing provided by lenders. For the Company's mortgage loans, the Company uses an estimate based on its knowledge of the mortgage market. The weighted average discount rate for the combined variable rate debt and mortgage loans used as of September 30, 2013 was 3.337%. An increase in the discount rate used in the discounted cash flow model would result in a decrease to the fair value of the Company's long-term debt. Conversely, a decrease in the discount rate used in the discounted cash flow model would result in an increase to the fair value of the Company's long-term debt.

Disclosure about the fair value of financial instruments is based upon pertinent information available to management as of September 30, 2013 and December 31, 2012. Although management is not aware of any factors that would significantly affect the fair value amounts, such amounts have not been comprehensively revalued for purposes of these financial statements since September 30, 2013, and current estimates of fair value may differ from the amounts presented herein.

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Intangible Assets Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Intangible Assets [Line Items]
Total Cost	$ 130,275	$ 152,611
Accumulated Amortization	(75,818)	(81,991)
Intangible Assets, net	54,457	70,620
In-place lease value
Intangible Assets [Line Items]
Total Cost	81,410	87,909
Accumulated Amortization	(42,629)	(42,894)
Intangible Assets, net	38,781	45,015
Tenant relationship value
Intangible Assets [Line Items]
Total Cost	46,160	56,137
Accumulated Amortization	(31,786)	(37,389)
Intangible Assets, net	14,374	18,748
Above market leases acquired
Intangible Assets [Line Items]
Total Cost	2,705	8,565
Accumulated Amortization	(1,403)	(1,708)
Intangible Assets, net	1,302	6,857
Below Market Leases Acquired [Member]
Intangible Assets [Line Items]
Total Cost	76,874	77,083
Accumulated Amortization	(48,374)	(43,224)
Intangible Assets, net	$ 28,500	$ 33,859

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Consolidated Statements of Operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue:
Rents	$ 116,479	$ 108,658	$ 347,680	$ 327,362
Tenant reimbursements	20,699	20,294	60,615	57,179
Termination fees	2,040	931	2,946	2,522
Third party management fees, labor reimbursement and leasing	3,263	3,007	9,652	9,021
Other	975	1,630	3,305	4,029
Total revenue	143,456	134,520	424,198	400,113
Expenses:
Property operating expenses	40,661	38,783	119,522	112,961
Real estate taxes	14,190	13,486	42,706	40,430
Third party management expenses	1,317	1,298	4,105	3,812
Depreciation and amortization	50,613	46,955	149,423	142,262
General and administrative expenses	6,436	6,080	20,322	18,209
Total operating expenses	113,217	106,602	336,078	317,674
Operating Income	30,239	27,918	88,120	82,439
Other Income (Expense):
Interest income	268	311	448	2,631
Historic tax credit transaction income	11,853	11,840	11,853	11,840
Interest expense	(30,338)	(32,620)	(91,689)	(99,745)
Interest expense — amortization of deferred financing costs	(1,158)	(1,218)	(3,502)	(3,790)
Interest expense — financing obligation	(264)	(230)	(693)	(608)
Equity in income of real estate ventures	714	500	3,757	1,382
Gain from remeasurement of investment in a real estate venture	0	0	7,847	0
Net gain on real estate venture transactions	0	0	3,683	0
Net loss on sale of undepreciated real estate	(129)	0	(129)	0
Loss on real estate venture formation	0	(950)	0	(950)
Loss on early extinguishment of debt	(11)	(51)	(1,127)	(1,549)
Income (Loss) from continuing operations	11,174	5,500	18,568	(8,350)
Discontinued operations:
Income (Loss) from discontinued operations	(70)	1,649	590	6,803
Net gain (loss) on disposition of discontinued operations	(16)	9,940	3,029	34,774
Total discontinued operations	(86)	11,589	3,619	41,577
Net income	11,088	17,089	22,187	33,227
Discontinued operations attributable to non-controlling interests, Basic	1	(211)	(48)	(760)
Net (income) loss attributable to non-controlling interests — LP units	(106)	(49)	(147)	335
Net income attributable to non-controlling interests	(105)	(260)	(195)	(425)
Net income attributable to Brandywine Realty Trust	10,983	16,829	21,992	32,802
Distribution to Preferred Shares	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share redemption charge	0	0	0	(2,090)
Amount allocated to unvested restricted shareholders	(85)	(95)	(278)	(286)
Net income attributable to Common Shareholders of Brandywine Realty Trust	9,173	13,949	16,539	22,594
Basic income (loss) per Common Share:
Continuing operations	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued operations	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income (loss) attributable to common shareholders/unitholders, Basic	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Diluted income (loss) per Common Share:
Continuing operations	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued operations	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income attributable to common shareholders/unitholders, Diluted	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Weighted Average Number of Shares Outstanding, Basic	156,703,348	143,424,485	151,933,441	143,182,911
Weighted Average Number of Shares Outstanding, Diluted	157,992,082	144,128,010	153,142,825	143,182,911
Net income (loss) attributable to Brandywine Realty Trust
Net income (loss) from continuing operations	11,068	5,451	18,421	(8,015)
Income (Loss) from discontinued operations	(85)	11,378	3,571	40,817
Net income	11,088	17,089	22,187	33,227
Net income (Loss) attributable to Brandywine Realty Trust	10,983	16,829	21,992	32,802
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Revenue:
Rents	116,479	108,658	347,680	327,362
Tenant reimbursements	20,699	20,294	60,615	57,179
Termination fees	2,040	931	2,946	2,522
Third party management fees, labor reimbursement and leasing	3,263	3,007	9,652	9,021
Other	975	1,630	3,305	4,029
Total revenue	143,456	134,520	424,198	400,113
Expenses:
Property operating expenses	40,661	38,783	119,522	112,961
Real estate taxes	14,190	13,486	42,706	40,430
Third party management expenses	1,317	1,298	4,105	3,812
Depreciation and amortization	50,613	46,955	149,423	142,262
General and administrative expenses	6,436	6,080	20,322	18,209
Total operating expenses	113,217	106,602	336,078	317,674
Operating Income	30,239	27,918	88,120	82,439
Other Income (Expense):
Interest income	268	311	448	2,631
Historic tax credit transaction income	11,853	11,840	11,853	11,840
Interest expense	(30,338)	(32,620)	(91,689)	(99,745)
Interest expense — amortization of deferred financing costs	(1,158)	(1,218)	(3,502)	(3,790)
Interest expense — financing obligation	(264)	(230)	(693)	(608)
Equity in income of real estate ventures	714	500	3,757	1,382
Gain from remeasurement of investment in a real estate venture	0	0	7,847	0
Net gain on real estate venture transactions	0	0	3,683	0
Net loss on sale of undepreciated real estate	(129)	0	(129)	0
Loss on real estate venture formation	0	(950)	0	(950)
Loss on early extinguishment of debt	(11)	(51)	(1,127)	(1,549)
Income (Loss) from continuing operations	11,174	5,500	18,568	(8,350)
Discontinued operations:
Income (Loss) from discontinued operations	(70)	1,649	590	6,803
Net gain (loss) on disposition of discontinued operations	(16)	9,940	3,029	34,774
Total discontinued operations	(86)	11,589	3,619	41,577
Net income	11,088	17,089	22,187	33,227
Distribution to Preferred Shares	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share redemption charge	0	0	0	(2,090)
Amount allocated to unvested restricted shareholders	(85)	(95)	(278)	(286)
Net income attributable to Common Shareholders of Brandywine Realty Trust	9,278	14,209	16,734	23,019
Basic income (loss) per Common Share:
Continuing operations	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued operations	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income (loss) attributable to common shareholders/unitholders, Basic	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Diluted income (loss) per Common Share:
Continuing operations	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued operations	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income attributable to common shareholders/unitholders, Diluted	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Weighted Average Number of Shares Outstanding, Basic	158,467,087	146,082,206	153,731,070	145,842,872
Weighted Average Number of Shares Outstanding, Diluted	159,755,821	146,785,731	154,940,454	145,842,872
Net income (loss) attributable to Brandywine Realty Trust
Net income (loss) from continuing operations	11,174	5,500	18,568	(8,350)
Income (Loss) from discontinued operations	(86)	11,589	3,619	41,577
Net income	$ 11,088	$ 17,089	$ 22,187	$ 33,227

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Organization of the Parent Company and The Operating Partnership

9 Months Ended

Sep. 30, 2013

Organization, Consolidation and Presentation of Financial Statements [Abstract]

ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP [Text Block]

ORGANIZATION OF THE PARENT COMPANY AND THE OPERATING PARTNERSHIP

The Parent Company is a self-administered and self-managed real estate investment trust (“REIT”) that provides leasing, property management, development, redevelopment, acquisition and other tenant-related services for a portfolio of office and industrial properties. The Parent Company owns its assets and conducts its operations through the Operating Partnership and subsidiaries of the Operating Partnership. The Parent Company is the sole general partner of the Operating Partnership and, as of September 30, 2013, owned a 98.8% interest in the Operating Partnership. The Parent Company’s common shares of beneficial interest are publicly traded on the New York Stock Exchange under the ticker symbol “BDN”.

As of September 30, 2013, the Company owned 210 properties, consisting of 182 office properties (one of which is held-for-sale), 19 industrial facilities, five mixed-use properties, one development property, two redevelopment properties and one re-entitlement property (collectively, the “Properties”) containing an aggregate of approximately 24.1 million net rentable square feet. In addition, as of September 30, 2013, the Company owned economic interests in 18 unconsolidated real estate ventures that contain approximately 6.2 million net rentable square feet (collectively, the “Real Estate Ventures”). As of September 30, 2013, the Company also owned 423 acres of undeveloped land, and held options to purchase approximately 51 additional acres of undeveloped land. As of September 30, 2013, the total potential development that these land parcels could support, under current zoning, entitlements or combination thereof, amounted to 6.1 million square feet. The Properties and the properties owned by the Real Estate Ventures are located in or near Philadelphia, Pennsylvania; Metropolitan Washington, D.C.; Southern New Jersey; Richmond, Virginia; Wilmington, Delaware; Austin, Texas and Oakland, Concord, and Carlsbad, California.

The Company conducts its third-party real estate management services business primarily through wholly-owned management company subsidiaries. As of September 30, 2013, the management company subsidiaries were managing properties containing an aggregate of approximately 30.7 million net rentable square feet, of which approximately 24.1 million net rentable square feet related to Properties owned by the Company and approximately 6.6 million net rentable square feet related to properties owned by third parties and Real Estate Ventures.

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Tax Credit Transactions

9 Months Ended

Sep. 30, 2013

Income Tax Disclosure [Abstract]

TAX CREDIT TRANSACTIONS

TAX CREDIT TRANSACTIONS

Historic Tax Credit Transaction

On November 17, 2008, the Company closed a transaction with US Bancorp (“USB”) related to the historic rehabilitation of the IRS Philadelphia Campus, a 862,692 square foot office building that is 100% leased to the IRS. On August 27, 2010, the Company completed the development of the IRS Philadelphia Campus and the IRS lease commenced. In connection with this completed development project, USB contributed to the Company $64.1 million of total project costs.

In exchange for its contributions to the development of the IRS Philadelphia Campus, USB is entitled to substantially all of the benefits derived from the tax rehabilitation credits available under section 47 of the Internal Revenue Code. USB does not have a material interest in the underlying economics of the property. This transaction includes a put/call provision whereby the Company may be obligated or entitled to repurchase USB’s interest in the IRS Philadelphia Campus. The Company believes the put will be exercised and the amount attributed to that puttable non-controlling interest obligation is included in other liabilities and is being accreted to the expected fixed put price.

Based on the contractual arrangements that obligate the Company to deliver tax benefits and provide other guarantees to USB and that entitle the Company through fee arrangements to receive substantially all available cash flow from the IRS Philadelphia Campus, the Company concluded that the IRS Philadelphia Campus should be consolidated. The Company also concluded that capital contributions received from USB, in substance, are consideration that the Company receives in exchange for its obligation to deliver tax credits and other tax benefits to USB. These receipts other than the amounts allocated to the put obligation will be recognized as revenue in the consolidated financial statements beginning when the obligation to USB is relieved which occurs upon delivery of the expected tax benefits net of any associated costs. The tax credit is subject to 20% recapture per year beginning one year after the completion of the IRS Philadelphia Campus. The total USB contributions presented within the Company’s consolidated balance sheet amounted to $26.8 million and $39.1 million as of September 30, 2013 and December 31, 2012, respectively. The contributions were recorded net of the amount allocated to non-controlling interest as described above of $2.7 million at the end of the period ended September 30, 2013 and $2.6 million at December 31, 2012, with the remaining balance being presented within deferred income. Beginning in September 2011 to September 2015, the Company recognized and will recognize, on an annual basis, the cash received as revenue net of allocated expenses over the five year credit recapture period as defined in the Internal Revenue Code within other income (expense) in its consolidated statements of operations. During the nine-month period ended September 30, 2013 the Company recognized $11.9 million in income related to the tax credits.

Direct and incremental costs incurred in structuring the transaction are deferred and will be recognized as expense in the consolidated financial statements upon the recognition of the related revenue as discussed above. The deferred cost at September 30, 2013 and December 31, 2012 is $1.0 million and $1.6 million, respectively, and is included in other assets in the Company’s consolidated balance sheet. Amounts included in interest expense related to the accretion of the non-controlling interest liability and the 2% return expected to be paid to USB on its non-controlling interest aggregate to $0.3 million and $1.0 million for the three and nine-month periods ended September 30, 2013, respectively, and $0.3 million and $1.0 million for the three and nine-month periods ended September 30, 2012, respectively.

New Markets Tax Credit Transaction

On December 30, 2008, the Company entered into a transaction with USB related to the Cira South Garage in Philadelphia, Pennsylvania and expects to receive a net benefit of $7.8 million under a qualified New Markets Tax Credit Program (“NMTC”). The NMTC was provided for in the Community Renewal Tax Relief Act of 2000 (the “Act”) and is intended to induce investment capital in under-served and impoverished areas of the United States. The Act permits taxpayers (whether companies or individuals) to claim credits against their Federal income taxes for up to 39% of qualified investments in qualified, active low-income businesses or ventures.

USB contributed $13.3 million to the development of the Cira South Garage and as such it is entitled to substantially all of the benefits derived from the tax credit, but it does not have a material interest in the underlying economics of the Cira South Garage. This transaction also includes a put/call provision whereby the Company may be obligated or entitled to repurchase USB’s interest. The Company believes the put will be exercised and an amount attributed to that obligation is included in other liabilities and is being accreted to the expected fixed put price. This put price is insignificant.

Based on the contractual arrangements that obligate the Company to deliver tax benefits and provide various other guarantees to USB, the Company concluded that the investment entities established to facilitate the NMTC transaction should be consolidated. The USB contribution of $13.3 million is included in deferred income on the Company’s consolidated balance sheets at each of September 30, 2013 and December 31, 2012. The USB contribution other than the amount allocated to the put obligation will be recognized as income in the consolidated financial statements when the tax benefits are delivered without risk of recapture to the tax credit investors and the Company’s obligation is relieved. The Company anticipates that it will recognize the net cash received as revenue within other income/expense in the year ended December 31, 2015. The NMTC is subject to 100% recapture for a period of seven years as provided in the Internal Revenue Code. The Company expects that the put/call provision will be exercised in 2017.

Direct and incremental costs incurred in structuring the transaction are deferred and will be recognized as expense in the consolidated financial statements upon the recognition of the related revenue as discussed above. The deferred cost at each of September 30, 2013 and December 31, 2012 is $5.3 million, and is included in other assets in the Company’s consolidated balance sheet.

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Beneficiaries Equity of the Parent Company Beneficiaries Equity of the Parent Company (Details Textuals) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	9 Months Ended		12 Months Ended	9 Months Ended	12 Months Ended	0 Months Ended	9 Months Ended	36 Months Ended	9 Months Ended		9 Months Ended		12 Months Ended		36 Months Ended
	Apr. 10, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Class A Units [Member]	Dec. 31, 2012 Class A Units [Member]	Jul. 15, 2013 Series E Preferred Stock [Member]	Sep. 30, 2013 Series E Preferred Stock [Member]	Mar. 10, 2013 Offering Program [Member]	Sep. 30, 2013 Dividend Declared [Member]	Oct. 18, 2013 Dividend Paid [Member]	Sep. 30, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Sep. 30, 2012 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Dec. 31, 2012 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Oct. 18, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Mar. 10, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P. Offering Program [Member]
Class of Stock [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount					1,763,739	2,657,721
Stock Issued During Period, Shares, New Issues	12,650,000
Additional shares granted under option to purchase in public offering	1,650,000
Proceeds from Issuance of Common Stock	$ 181,700	$ 181,527	$ 0									$ 181,527	$ 0
Common Stock, Dividends, Per Share, Declared										$ 0.15
Distributions payable		25,579		23,652							23,800	25,579		23,652	23,800
Preferred Stock, Shares Issued		4,000,000		4,000,000								4,000,000		4,000,000
Preferred Stock, Dividend Rate, Percentage		6.90%		6.90%				6.90%				6.90%		6.90%
Preferred Stock, Liquidation Preference Per Share								$ 25.00
Dividends, Preferred Stock, Cash		$ 5,175	$ 7,832				$ 1,700
Common Stock, Shares Authorized		200,000,000		200,000,000					15,000,000
Maximum percentage of Gross sale price per share compensation to sales agents									2.00%
Stock Issued During Period, Shares, Other									6,421,553							6,421,553
Average Sales Price Per Share									$ 12.50
Additional shares Expected to be purchased under program		539,200

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Debt Obligations Debt Obligations (Outstanding Unsecured Notes in Series of Transactions) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Extinguishment of Debt [Line Items]
Early Repayment of Senior Debt	$ 12,986
Extinguishment of Debt, Principal	11,900
Gains (Losses) on Extinguishment of Debt, before Write off of Deferred Debt Issuance Cost	(1,127)
Write off of Deferred Debt Issuance Cost	23
2014 5.400% Notes
Extinguishment of Debt [Line Items]
Early Repayment of Senior Debt	6,570
Extinguishment of Debt, Principal	6,180
Gains (Losses) on Extinguishment of Debt, before Write off of Deferred Debt Issuance Cost	(401)
Write off of Deferred Debt Issuance Cost	7
2015 7.500% Notes
Extinguishment of Debt [Line Items]
Early Repayment of Senior Debt	5,843
Extinguishment of Debt, Principal	5,210
Gains (Losses) on Extinguishment of Debt, before Write off of Deferred Debt Issuance Cost	(663)
Write off of Deferred Debt Issuance Cost	15
2016 6.000% Notes
Extinguishment of Debt [Line Items]
Early Repayment of Senior Debt	573
Extinguishment of Debt, Principal	510
Gains (Losses) on Extinguishment of Debt, before Write off of Deferred Debt Issuance Cost	(63)
Write off of Deferred Debt Issuance Cost	$ 1

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Risk Management and Use of Financial Instruments

9 Months Ended

Sep. 30, 2013

Derivative Instruments and Hedging Activities Disclosure [Abstract]

RISK MANAGEMENT AND USE OF FINANCIAL INSTRUMENTS [Text Block]

RISK MANAGEMENT AND USE OF FINANCIAL INSTRUMENTS

Risk Management

In the course of its ongoing business operations, the Company encounters economic risk. There are three main components of economic risk: interest rate risk, credit risk and market risk. The Company is subject to interest rate risk on its interest-bearing liabilities. Credit risk is primarily the risk of inability or unwillingness of tenants to make contractually required payments and of counterparties on derivatives contracts to fulfill their obligations. Market risk is the risk of declines in the value of Company properties due to changes in rental rates, interest rates, supply and demand of similar products and other market factors affecting the valuation of properties.

Risks and Uncertainties

Challenging economic conditions have reduced the volume of real estate transactions and created credit stresses on many businesses. Vacancy rates may increase through the remainder of 2013 and possibly beyond as the current economic climate continues to negatively impact tenants. The current financial markets also have an adverse effect on the Company’s Real Estate Venture partners and contractual counter parties, including counter parties in derivative contracts.

The Company was in compliance with all financial covenants as of September 30, 2013. Management continuously monitors the Company’s compliance with and anticipated compliance with the covenants. Certain of the covenants restrict the Company’s ability to obtain alternative sources of capital. While the Company currently believes it will remain in compliance with its covenants, in the event of a continued slow-down or deterioration in the economy, the Company may not be able to remain in compliance with such covenants, in which case a default would result absent a lender waiver.

Derivative Financial Instruments

The following table summarizes the terms and fair values of the Company's derivative financial instruments as of September 30, 2013 and December 31, 2012. The notional amounts provide an indication of the extent of the Company's involvement in these instruments at that time, but do not represent exposure to credit, interest rate or market risks (amounts presented in thousands).

Hedge Product	Hedge Type	Designation		Notional Amount				Strike		Trade Date	Maturity Date	Fair value
				09/30/2013		12/31/2012						09/30/2013			12/31/2012
Assets:
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.300	%	December 22, 2011	January 30, 2021	112			(1,262		)
				$	25,774	$	25,774					$	112		$	(1,262	)
Liabilities:
Swap	Interest Rate	Cash Flow	(a)	$	200,000	$	200,000	3.623	%	December 6-13, 2011	February 1, 2019	$	(2,369	)	$	(8,859	)
Swap	Interest Rate	Cash Flow	(a)	77,000		77,000		2.703	%	December 9-13, 2011	February 1, 2016	(942		)	(1,343		)
Swap	Interest Rate	Cash Flow	(a)	50,000		50,000		2.470	%	December 13, 2011	February 1, 2015	(327		)	(458		)
Swap	Interest Rate	Cash Flow	(a)	23,000		23,000		2.513	%	December 7-12, 2011	May 1, 2015	(181		)	(245		)
Swap	Interest Rate	Cash Flow	(a)	27,062		27,062		2.750	%	December 21, 2011	September 30, 2017	(410		)	(914		)
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.090	%	January 6, 2012	October 30, 2019	(85		)	(1,129		)
				$	402,836	$	402,836					$	(4,314	)	$	(12,948	)

(a) Hedging unsecured variable rate debt.

The Company measures its derivative instruments at fair value and records them in the balance sheet as either an asset or liability. As of September 30, 2013, one interest rate swap held an asset position and was included in other assets on the Company's consolidated balance sheets. The remaining swaps are included in other liabilities on the Company's consolidated balance sheets.

Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. The Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy.

Concentration of Credit Risk

Concentrations of credit risk arise for the Company when multiple tenants of the Company are engaged in similar business activities, or are located in the same geographic region, or have similar economic features that impact in a similar manner their ability to meet contractual obligations, including those to the Company. The Company regularly monitors its tenant base to assess potential concentrations of credit risk. Management believes the current credit risk portfolio is reasonably well diversified and does not contain an unusual concentration of credit risk. No tenant accounted for 10% or more of the Company’s rents during the three and nine-month periods ended September 30, 2013 and 2012. Conditions in the general economy and the global credit markets have had a significant adverse effect on numerous industries. The Company has tenants concentrated in various industries that may be experiencing adverse effects from the current economic conditions and the Company could be adversely affected if such tenants were to default under their leases.

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Investment in Unconsolidated Ventures Investment in Unconsolidated Ventures (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended			0 Months Ended		9 Months Ended		0 Months Ended	9 Months Ended			0 Months Ended
	Sep. 30, 2013 acre Real_Estate_Ventures Buildings Room sqft	Sep. 30, 2012	Sep. 30, 2013 acre Real_Estate_Ventures Buildings Room sqft	Sep. 30, 2012	Dec. 31, 2012	Jul. 31, 2013 4040 Wilson Venture [Member] acre Storey	Jun. 19, 2013 Two Tower Bridge [Member]	Sep. 30, 2013 The Grove at Cira Centre South [Member]	Jan. 25, 2013 The Grove at Cira Centre South [Member] Storey beds acre	Jun. 19, 2013 Six Tower Bridge [Member]	Sep. 30, 2013 Six Tower Bridge [Member]	Mar. 26, 2013 BDN Beacon Venture LLC [Member]	Jan. 25, 2013 HSRE, LLC [Member] [Member] The Grove at Cira Centre South [Member]	Jul. 31, 2013 Ashton Park [Member] 4040 Wilson Venture [Member]	Jul. 31, 2013 Brandywine Realty Trust [Member] 4040 Wilson Venture [Member]	Jan. 25, 2013 Campus Crest Properties, LLC [Member] The Grove at Cira Centre South [Member]
Schedule of Equity Method Investments [Line Items]
Gain from remeasurement of investment in a real estate venture	$ 0	$ 0	$ 7,847,000	$ 0							$ 7,800,000
Number of floors of a building						20			33
Student housing bed capacity									850
Company's share of equity (Company's Basis)	194,572,000		194,572,000		193,555,000		(100,000)					17,000,000
Net gain on real estate venture transactions	0	0	3,683,000	0
Number of unconsolidated investments in Real Estate Ventures	18		18
Number of real estate ventures that owns buildings	12		12
Number of office buildings in Real Estate Ventures	50		50
Aggregate Approximate Area Of Office Buildings	6,200,000		6,200,000
Number of real estate ventures that owns undeveloped land	4		4
Area Owned By Real Estate Venture Of Undeveloped Parcels Of Land	25.3		25.3			1.3			1
Fair value of land, net of amount encumbered														36,000,000
Equity Method Investment, Underlying Equity in Net Assets									8,500,000
Equity Method Investment, Budgeted Total Project Cost						194,300,000		158,500,000
Payments to Acquire Equity Method Investments			30,142,000	49,763,000		72,000,000		60,700,000
Payments to Acquire Interest in Joint Venture															36,000,000
Construction Loan						122,300,000		97,800,000
Equity Method Investment, Aggregate Cost									6,000,000
Equity Method Investment, Difference Between Carrying Amount and Underlying Equity									2,500,000
Number of real estate ventures that owns land under development	1		1
Area Owned By Real Estate Venture in Parcels Of Land Under Development	1.0		1.0
Number of real estate ventures developed hotel property	1		1
Number Of Rooms Contain In One Real Estate Venture Developed As Hotel Property	137		137
Minimum Percentage Of Unconsolidated Equity Method Investment Ownership			20.00%
Maximum Percentage Of Unconsolidated Equity Method Investment Ownership			65.00%
Guarantor Obligations, Current Carrying Value	600,000		600,000
Guarantor Obligations, Maximum Exposure, Undiscounted								23,000,000
Equity Method Investment, Ownership Percentage						50.00%						20.00%	40.00%			30.00%
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net										24,500,000
Business Acquisition Purchase Price Allocation Building										14,800,000
Business Acquisition Purchase Price Allocation, Land										6,900,000
Business Acquisition Purchase Price Allocation Intangible Assets										3,300,000
Business Acquisition Purchase Price Allocated To Market Lease Liabilities										500,000
Investments, Fair Value Disclosure							$ 3,600,000

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Debt Obligations Debt Obligations (Aggregate Scheduled Principal Payments of Debt Obligation, Excluding Amortization of Discounts and Premiums) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Extinguishment of Debt [Line Items]
2013	$ 2,886
2014	244,141
2015	411,358
2016	346,528
2017	330,323
Thereafter	1,047,407
Total principal payments	2,382,643
Net unamortized premiums/(discounts)	(5,452)
Total Debt Obligations	$ 2,377,191	$ 2,465,330

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Beneficiaries Equity of the Parent Company Beneficiaries Equity of the Parent Company (Tables)

9 Months Ended

Sep. 30, 2013

Equity [Abstract]

Earnings Per Share (EPS), Basic and Diluted

Earnings per Share (EPS)

The following tables detail the number of shares and net income used to calculate basic and diluted earnings per share (in thousands, except share and per share amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Net (income) from continuing operations attributable to non-controlling interests	(106		)	(106		)	(49		)	(49		)
Amount allocable to unvested restricted shareholders	(85		)	(85		)	(95		)	(95		)
Preferred share dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common shareholders	9,258			9,258			2,571			2,571
Income (Loss) from discontinued operations	(86		)	(86		)	11,589			11,589
Discontinued operations attributable to non-controlling interests	1			1			(211		)	(211		)
Discontinued operations attributable to common shareholders	(85		)	(85		)	11,378			11,378
Net income attributable to common shareholders	$	9,173		$	9,173		$	13,949		$	13,949
Denominator
Weighted-average shares outstanding	156,703,348			156,703,348			143,424,485			143,424,485
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average shares outstanding	156,703,348			157,992,082			143,424,485			144,128,010
Earnings per Common Share:
Income from continuing operations attributable to common shareholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common shareholders	—			—			0.08			0.08
Net income attributable to common shareholders	$	0.06		$	0.06		$	0.10		$	0.10

	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Net (income) loss from continuing operations attributable to non-controlling interests	(147		)	(147		)	335			335
Amount allocable to unvested restricted shareholders	(278		)	(278		)	(286		)	(286		)
Preferred share dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred share redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common shareholders	12,968			12,968			(18,223		)	(18,223		)
Income from discontinued operations	3,619			3,619			41,577			41,577
Discontinued operations attributable to non-controlling interests	(48		)	(48		)	(760		)	(760		)
Discontinued operations attributable to common shareholders	3,571			3,571			40,817			40,817
Net income attributable to common shareholders	$	16,539		$	16,539		$	22,594		$	22,594
Denominator
Weighted-average shares outstanding	151,933,441			151,933,441			143,182,911			143,182,911
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average shares outstanding	151,933,441			153,142,825			143,182,911			143,182,911
Earnings per Common Share:
Income (Loss) from continuing operations attributable to common shareholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common shareholders	0.02			0.02			0.29			0.29
Net income attributable to common shareholders	$	0.11		$	0.11		$	0.16		$	0.16

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Subsequent Events

9 Months Ended

Sep. 30, 2013

Subsequent Events [Abstract]

Subsequent Events [Text Block]

SUBSEQUENT EVENTS

Austin Venture

On October 16, 2013, the Company contributed a portfolio of seven office properties containing an aggregate of 1,398,826 square feet located in Austin, Texas (the "Austin Properties") to a newly-formed joint venture (the "Austin Venture") with G&I VII Austin Office LLC (“DRA”), an investment vehicle advised by DRA Advisors LLC. The Austin Properties and related assets represent the Company's entire remaining property portfolio within the Austin, Texas region. DRA and the Company, based on arm's-length negotiation, agreed to an aggregate gross sales price of $330.0 million subject to an obligation on the Company's part to fund the first $5.2 million of post-closing capital expenditures.

DRA owns a 50% interest in the Austin Venture and the Company owns a 50% interest in the Austin Venture, subject to the Company's right to receive up to an additional 10% of distributions.

At the closing the Austin Venture obtained third party non-recourse debt financing of approximately $230.6 million secured by mortgages on the Austin Properties and used proceeds of this financing together with $49.7 million of cash contributions by DRA (less $1.9 million of closing costs and $6.9 million of closing prorations and lender holdbacks) to fund a $271.5 million distribution to the Company. The Company has agreed to fund the first $5.2 million of post-closing capital expenditures on behalf of the Austin Venture, resulting in net proceeds of $266.3 million after funding the Company's capital expenditure obligation. As part of the transaction, the Company's subsidiary management company executed an agreement with the Austin Venture to provide property management and leasing services to the Austin Venture in exchange for a market-based fee.

The Company and DRA, utilizing additional equity funding of up to $100.0 million per partner and to-be-determined third-party debt financing, intend to jointly pursue additional office opportunities in targeted Austin sub-markets and plan to co-invest in acquisitions that meet certain investment criteria.

Cira Walnut Tower

On October 31, 2013 the Company signed a lease with FMC Corporation for approximately 245,000 square feet of office space at the Cira Walnut Tower ("Cira Walnut"), which is an office and residential tower that the Company will develop at 30th and Walnut Streets in Philadelphia on a site ground leased from the University of Pennsylvania. The lease with FMC has an initial term of sixteen (16) years from initial occupancy. In addition, the Company also leased approximately 100,000 square feet of office space to the University of Pennsylvania under a twenty-year lease. Cira Walnut will be known as The FMC Tower at Cira Centre South.

The Company's ground lease with the University of Pennsylvania has a term through July 2097, with a variable rent that would provide the University with a percentage of the cash flow or proceeds of specified capital events subject to receipt by the Company of a priority return on the Company's investment.

The Company has evaluated subsequent events through the date the financial statements were issued.

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Commitments and Contingencies

9 Months Ended

Sep. 30, 2013

Commitments and Contingencies Disclosure [Abstract]

COMMITMENTS AND CONTINGENCIES [Text Block]

COMMITMENTS AND CONTINGENCIES

Legal Proceedings

The Company is involved from time to time in litigation on various matters, including disputes with tenants and disputes arising out of agreements to purchase or sell properties. Given the nature of the Company’s business activities, these lawsuits are considered routine to the conduct of its business. The result of any particular lawsuit cannot be predicted, because of the very nature of litigation, the litigation process and its adversarial nature, and the jury system. The Company does not expect that the liabilities, if any, that may ultimately result from such legal actions will have a material adverse effect on the consolidated financial position, results of operations or cash flows of the Company.

Environmental

As an owner of real estate, the Company is subject to various environmental laws of federal, state, and local governments. The Company’s compliance with existing laws has not had a material adverse effect on its financial condition and results of operations, and the Company does not believe it will have a material adverse effect in the future. However, the Company cannot predict the impact of unforeseen environmental contingencies or new or changed laws or regulations on its current Properties or on properties that the Company may acquire.

Ground Rent

Future minimum rental payments under the terms of all non-cancelable ground leases under which the Company is the lessee are expensed on a straight-line basis regardless of when payments are due. The Company’s ground leases have remaining lease terms ranging from 16 to 90 years. Minimum future rental payments on non-cancelable leases at September 30, 2013 are as follows (in thousands):

2013 (three months remaining)	$	549
2014	2,288
2015	2,288
2016	2,288
2017	2,288
Thereafter	280,519
Total	$	290,220

One of the land leases for a property provides for contingent rent participation by the lessor in certain capital transactions and net operating cash flows of the property after certain returns are achieved by the Company. Such amounts, if any, will be reflected as contingent rent when incurred. The leases also provide for payment by the Company of certain operating costs relating to the land, primarily real estate taxes. The above schedule of future minimum rental payments does not include any contingent rent amounts or any reimbursed expenses.

The Company acquired ground tenancy rights under a long term ground lease agreement related to its acquisition of 3020 Market Street in Philadelphia, Pennsylvania on August 12, 2011. The annual rental payments under this ground lease is equal to a percentage of the net operating income generated by the property. The Company has not included the amounts in the table above since such amounts are not fixed or determinable.

Other Commitments or Contingencies

As part of the Company’s September 2004 acquisition of a portfolio of properties from The Rubenstein Company (which the Company refers to as the "TRC acquisition"), the Company acquired its interest in Two Logan Square, a 708,844 square foot office building in Philadelphia, primarily through its ownership of a second and third mortgage secured by this property. This property is consolidated, as the borrower is a variable interest entity and the Company, through its ownership of the second and third mortgages, is the primary beneficiary. The Company currently does not expect to take title to Two Logan Square until, at the earliest, September 2019. If the Company takes fee title to Two Logan Square upon a foreclosure of its mortgage, the Company has agreed to pay an unaffiliated third party that holds a residual interest in the fee owner of this property an amount equal to $2.9 million. On the TRC acquisition date, the Company recorded a liability of $0.7 million and this amount will accrete up to $2.9 million through September 2019. As of September 30, 2013, the Company had a balance of $1.6 million for this liability in its consolidated balance sheet.

The Company was audited by the Internal Revenue Service (the “IRS”) for its 2004 tax year. The audit concerned the tax treatment of the TRC acquisition in September 2004 in which the Company acquired a portfolio of properties through the acquisition of a limited partnership. On December 17, 2010, the Company received notice that the IRS proposed an adjustment to the allocation of recourse liabilities allocated to the contributor of the properties. The Company appealed the proposed adjustment and during the second quarter of 2013, the IRS finalized a settlement agreement which will not result in a material liability to the Company for federal income taxes. The contributor of partnership interests in the 2004 transaction has agreed not to assert a claim against the Company for federal income tax purposes under the tax protection agreement entered into as part of the transaction.

As part of the Company’s 2006 merger with Prentiss Properties Trust ("Prentiss"), the 2004 TRC acquisition and several of our other transactions, the Company agreed not to sell certain of the properties it acquired in transactions that would trigger taxable income to the former owners. In the case of the TRC acquisition, the Company agreed not to sell acquired properties in non-exempt transactions for periods up to 15 years from the date of the TRC acquisition as follows at September 30, 2013: One Rodney Square and 130/150/170 Radnor Financial Center (January, 2015); and One Logan Square, Two Logan Square and Radnor Corporate Center (January, 2020). In the Prentiss acquisition, the Company assumed the obligation of Prentiss not to sell Concord Airport Plaza before March, 2018. The Company’s agreements generally provide that it may dispose of the subject properties only in transactions that qualify as tax-free exchanges under Section 1031 of the Internal Revenue Code or in other tax deferred transactions. If the Company were to sell a restricted property before expiration of the restricted period in a non-exempt transaction, the Company may be required to make significant payments to the parties who sold the applicable property on account of tax liabilities attributed to them.

As part of the Company’s acquisition of properties from time to time in tax-deferred transactions, the Company has agreed to provide certain of the prior owners of the acquired properties with the right to guarantee the Company’s indebtedness. If the Company were to seek to repay the indebtedness guaranteed by the prior owner before the expiration of the applicable agreement, the Company would be required to provide the prior owner an opportunity to guaranty qualifying replacement debt. These debt maintenance agreements may limit the Company’s ability to refinance indebtedness on terms favorable to the Company.

During 2008, in connection with the development of the IRS Philadelphia Campus and the Cira South Garage, the Company entered into a historic tax credit and a new market tax credit arrangement, respectively. The Company is required to be in compliance with various laws, regulations and contractual provisions that apply to its historic and new market tax credit arrangements. Non-compliance with applicable requirements could result in projected tax benefits not being realized and require a refund to USB or reduction of investor capital contributions, which are reported as deferred income in the Company’s consolidated balance sheet, until such time as its obligation to deliver tax benefits is relieved. The compliance periods for the tax credit arrangements run through 2015. The Company does not anticipate that any material refunds or reductions of investor capital contributions will be required in connection with these arrangements.

The Company invests in its properties and regularly incurs capital expenditures in the ordinary course to maintain the properties. The Company believes that such expenditures enhance its competitiveness. The Company also enters into construction, utility and service contracts in the ordinary course of business which may extend beyond one year. These contracts typically provide for cancellation with insignificant or no cancellation penalties.

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Real Estate Investments Gross Carrying Value of Company's Properties (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Property, Plant and Equipment, Gross [Abstract]
Land	$ 664,952	$ 662,107
Buildings and Improvements, Gross	3,465,544	3,576,065
Leasehold Improvements, Gross	501,414	487,997
Real Estate Investments	$ 4,631,910	$ 4,726,169

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Debt Obligations Debt Obligations (Tables)

9 Months Ended

Sep. 30, 2013

Debt Disclosure [Abstract]

Consolidated Debt Obligations [Table Text Block]

The following table sets forth information regarding the Company’s consolidated debt obligations outstanding at September 30, 2013 and December 31, 2012 (in thousands):

Property / Location	September 30, 2013			December 31, 2012			Effective Interest Rate			Maturity Date
MORTGAGE DEBT:
Tysons Corner	$	91,855		$	93,188		5.36	%	(a)	Aug-15
Two Logan Square	88,782			89,340			7.57	%		Apr-16
Fairview Eleven Tower	21,754			22,000			4.25	%		Jan-17
IRS Philadelphia Campus	192,535			197,111			7.00	%		Sep-30
Cira South Garage	40,664			42,303			7.12	%		Sep-30
Principal balance outstanding	435,590			443,942
Plus: fair market value premiums (discounts), net	(695		)	(968		)
Total mortgage indebtedness	$	434,895		$	442,974
UNSECURED DEBT:
Credit Facility	—			69,000			LIBOR + 1.50%			Feb-16
Three-Year Term Loan - Swapped to fixed	150,000			150,000			2.60	%		Feb-15
Four-Year Term Loan - Variable	100,000			100,000			LIBOR + 1.75%			Feb-16
Seven-Year Term Loan - Swapped to fixed	200,000			200,000			3.62	%		Feb-19
$250.0M 5.400% Guaranteed Notes due 2014	232,199			238,379			5.53	%		Nov-14
$250.0M 7.500% Guaranteed Notes due 2015	161,325			166,535			7.76	%		May-15
$250.0M 6.000% Guaranteed Notes due 2016	149,919			150,429			5.95	%		Apr-16
$300.0M 5.700% Guaranteed Notes due 2017	300,000			300,000			5.68	%		May-17
$325.0M 4.950% Guaranteed Notes due 2018	325,000			325,000			5.13	%		Apr-18
$250.0M 3.950% Guaranteed Notes due 2023	250,000			250,000			4.02	%		Feb-23
Indenture IA (Preferred Trust I)	27,062			27,062			2.75	%		Mar-35
Indenture IB (Preferred Trust I)	25,774			25,774			3.30	%		Apr-35
Indenture II (Preferred Trust II)	25,774			25,774			3.09	%		Jul-35
Principal balance outstanding	1,947,053			2,027,953
Plus: original issue premiums (discounts), net	(4,757		)	(5,597		)
Total unsecured indebtedness	$	1,942,296		$	2,022,356
Total Debt Obligations	$	2,377,191		$	2,465,330

Summary Of Debt Repurchases [Table Text Block]

During the nine months ended September 30, 2013, the Company repurchased $11.9 million in principal amount of its outstanding unsecured notes in a series of transactions that are summarized in the following table (in thousands):

Notes	Repurchase Amount		Principal		Loss			Deferred Financing Amortization
2014 5.400% Notes	$	6,570	$	6,180	$	(401	)	$	7
2015 7.500% Notes	5,843		5,210		(663		)	15
2016 6.000% Notes	573		510		(63		)	1
	$	12,986	$	11,900	$	(1,127	)	$	23

Schedule of Maturities of Long-term Debt [Table Text Block]

As of September 30, 2013, the Company’s aggregate scheduled principal payments on debt obligations, excluding amortization of discounts and premiums, were as follows (in thousands):

2013 (three months remaining)	$	2,886
2014	244,141
2015	411,358
2016	346,528
2017	330,323
Thereafter	1,047,407
Total principal payments	2,382,643
Net unamortized premiums/(discounts)	(5,452		)
Outstanding indebtedness	$	2,377,191

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Share Based and Deferred Compensation Share Based and Deferred Compensation (Tables)

9 Months Ended

Sep. 30, 2013

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Options Activity [Table Text Block]

Option activity as of September 30, 2013 and changes during the nine months ended September 30, 2013 were as follows:

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at January 1, 2013	3,337,549		$	14.50	7.2	$	—
Granted	—		—		—	—
Exercised	(207,941	)	$	10.52	—	—
Canceled	(117,662	)	$	18.61
Outstanding at September 30, 2013	3,011,946		$	15.40	5.4	$	—
Vested/Exerciseable at September 30, 2013	2,827,517		$	15.63	5.3	$	—

Company's Restricted Share Activity [Table Text Block]

The following table summarizes the Company’s restricted share activity for the nine months ended September 30, 2013:

	Shares		Weighted Average Grant Date Fair value
Non-vested at January 1, 2013	597,708		$	9.46
Granted	182,576		13.13
Vested	(208,306	)	13.13
Forfeited	(8,265	)	11.41
Non-vested at September 30, 2013	563,713		$	12.56

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Investment in Unconsolidated Ventures Investment in Unconsolidated Ventures (Summary of Results of Operations of Unconsolidated Ventures) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Schedule of Equity Method Investments [Line Items]
Company's share of income (Company's basis)	$ 714	$ 500	$ 3,757	$ 1,382
Unconsolidated Real Estate Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Revenue	30,684	42,772	108,500	120,644
Operating expenses	13,199	18,753	48,671	51,819
Interest expense, net	9,223	10,233	28,167	31,100
Depreciation and amortization	9,893	12,947	33,778	36,067
Net income (loss)	(1,631)	839	(2,116)	1,658
Company's share of income (Company's basis)	$ 714	$ 500	$ 3,757	$ 1,382

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Investment in Unconsolidated Ventures Investment in Unconsolidated Ventures (Tables)

9 Months Ended

Sep. 30, 2013

Equity Method Investments and Joint Ventures [Abstract]

Equity Method Investment Summarized Financial Information [Table Text Block]

The following is a summary of the financial position of the Real Estate Ventures as of September 30, 2013 and December 31, 2012 (in thousands):

	September 30, 2013		December 31, 2012
Net property	$	879,838	$	923,536
Other assets	164,508		174,677
Other liabilities	36,115		53,645
Debt	707,847		724,780
Equity	300,384		319,788
Company’s share of equity (Company’s basis) (a)	194,572		193,555

Summary of results of operations of unconsolidated Real Estate Venture [Table Text Block]

The following is a summary of results of operations of the Real Estate Ventures for the three and nine-month periods ended September 30, 2013 and 2012 (in thousands):

	Three-month periods ended September 30,					Nine-month periods ended September 30,
	2013			2012		2013			2012
Revenue	$	30,684		$	42,772	$	108,500		$	120,644
Operating expenses	13,199			18,753		48,671			51,819
Interest expense, net	9,223			10,233		28,167			31,100
Depreciation and amortization	9,893			12,947		33,778			36,067
Net income (loss)	(1,631		)	839		(2,116		)	1,658
Company’s share of income (Company’s basis)	714			500		3,757			1,382

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Discontinued Operations Discontinued Operations (Details Textuals) (Details)	9 Months Ended
	Sep. 30, 2013 Properties	Sep. 30, 2012 Properties
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties sold	12	26
Assets Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of Real Estate Properties	1

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Share Based and Deferred Compensation Share Based and Deferred Compensation (Details Textuals) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			9 Months Ended		3 Months Ended		9 Months Ended			48 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Stock Option [Member]	Sep. 30, 2012 Stock Option [Member]	Sep. 30, 2013 Stock Option [Member]	Sep. 30, 2012 Stock Option [Member]	Sep. 30, 2013 Restricted Stock [Member]	Sep. 30, 2012 Restricted Stock [Member]	Sep. 30, 2013 Restricted Stock [Member]	Sep. 30, 2012 Restricted Stock [Member]	Dec. 31, 2012 Restricted Stock [Member]	Sep. 30, 2013 Restricted Stock [Member] Minimum [Member]	Sep. 30, 2013 Restricted Stock [Member] Maximum [Member]	Sep. 30, 2013 Restricted Performance Share Units Plan [Member] Employees	Sep. 30, 2012 Restricted Performance Share Units Plan [Member]	Sep. 30, 2013 Restricted Performance Share Units Plan [Member] Age Employees	Sep. 30, 2012 Restricted Performance Share Units Plan [Member]	Sep. 30, 2011 Restricted Performance Share Units Plan [Member]	Dec. 31, 2012 Restricted Performance Share Units Plan [Member]	Sep. 30, 2013 Executive Officer [Member] Restricted Stock [Member] Employees	Feb. 25, 2013 Executive Officer [Member] Restricted Stock [Member]	Feb. 25, 2013 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 01, 2012 Executive Officer [Member] Restricted Performance Share Units Plan [Member]	Mar. 02, 2011 Executive Officer [Member] Restricted Performance Share Units Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Voluntary Termination Of Employment Terms											after reaching age 57 and accumulating at least 15 years of service with the Company							after reaching age 57 and accumulating at least 15 years of service with the Company
Accumulated Service Period For Voluntary Termination											15 years							15 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Minimum			3 years								3 years			3 years	7 years			3 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period											three to seven years from the initial grant date
Maximum Percentage Of Participants Base Units																		200.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																							157,208	231,093	242,122	113,256
Number of executives with employment agreements																2		2				2
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Total Fair Value																		$ 4.1	$ 4.2	$ 2.0
Age Limit Of Voluntary Termination Of Employment																		57
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number									563,713		563,713		597,708
Vested/Exerciseable, shares	2,827,517		2,827,517		2,827,517		2,827,517
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition								0 years 4 months 25 days			1 year 4 months 24 days
Share Based Compensation Arrangement By Share Based Payment Stock Options Nonvested Number					184,429		184,429
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized					0.2		0.2		2.4		2.4
Allocated Share-based Compensation Expense	2.3	1.8	7.0	5.5	0.2	0.4	0.6	1.1	0.9	0.8	2.6	2.3				1.3	0.7	3.7	2.1
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	$ 0.3	$ 0.5	$ 1.1	$ 1.4		$ 0.1	$ 0.1	$ 0.3	$ 0.1	$ 0.2	$ 0.4	$ 0.5				$ 0.2	$ 0.2	$ 0.6	$ 0.6
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period											208,306										64,678

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Discontinued Operations Discontinued Operations (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenue:
Rents	$ 116,479	$ 108,658	$ 347,680	$ 327,362
Other Real Estate Revenue	975	1,630	3,305	4,029
Tenant reimbursements	20,699	20,294	60,615	57,179
Total revenue	143,456	134,520	424,198	400,113
Expenses:
Property operating expenses	40,661	38,783	119,522	112,961
Real estate taxes	14,190	13,486	42,706	40,430
Depreciation and amortization	50,613	46,955	149,423	142,262
Total operating expenses	113,217	106,602	336,078	317,674
Interest income	268	311	448	2,631
Income from discontinued operations before gain on sale of interests in real estate	(70)	1,649	590	6,803
Net gain on disposition of discontinued operations	(16)	9,940	3,029	34,774
Income (Loss) from discontinued operations	(86)	11,589	3,619	41,577
Assets Held-for-sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets Held-for-sale, Long Lived	3,724		3,724
Real Estate Accumulated Depreciation Related to Properties Held for Sal	(1,399)		(1,399)
Operating Real Estate Investment Properties Held for Sale, Net	2,325		2,325
Development In Process Related to Properties Held-for-sale	0		0
Real Estate Investment Properties Held for Sale, Net	2,325		2,325
Other Assets Related to Assets Held-for-Sale	46		46
Assets Held-for-sale, Current	2,371		2,371
Discontinued Operations [Member]
Revenue:
Rents	0	5,602	4,129	22,282
Termination fees		4		11
Other Real Estate Revenue	0	129	123	318
Tenant reimbursements	3	386	334	1,872
Total revenue	3	6,121	4,586	24,483
Expenses:
Property operating expenses	38	1,977	1,672	6,863
Real estate taxes	17	707	557	2,717
Depreciation and amortization	18	1,788	1,769	8,106
Total operating expenses	73	4,472	3,998	17,686
Interest income	0	0	2	6
Income from discontinued operations before gain on sale of interests in real estate	(70)	1,649	590	6,803
Net gain on disposition of discontinued operations	(16)	9,940	3,029	34,774
Income (Loss) from discontinued operations	$ (86)	$ 11,589	$ 3,619	$ 41,577

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Organization of the Parent Company and The Operating Partnership Organization of the Parent Company and The Operating Partnership (Details)	Sep. 30, 2013
Organization of The Parent Company and The Operating Partnership [Line Items]
Ownership in the Operating Partnership	98.80%
Parent Company [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Net rentable square feet	24,100,000
Area Owned By Company Of Undeveloped Parcels Of Land	423
Area Of Additional Undeveloped Parcels Of Land With Option to Purchase	51
Total potential development capacity	6,100,000
Unconsolidated Real Estate Ventures [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Net rentable square feet	6,200,000
Number Of Unconsolidated Real Estate Ventures	18
Wholly-owned Management Company Subsidiaries [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Net rentable square feet	30,700,000
Third Parties and Real Estate Ventures [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Net rentable square feet	6,600,000
Total Properties [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	210
Office Properties [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	182
Assets Held-for-sale [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	1
Industrial Facilities [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	19
Mixed Use Properties [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	5
Development Property [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	1
Redevelopment Property [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	2
Re-entitlement Property [Member]
Organization of The Parent Company and The Operating Partnership [Line Items]
Number of Real Estate Properties	1

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Partners Equity of the Operating Partnership (Details Textuals) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	9 Months Ended		12 Months Ended	9 Months Ended		12 Months Ended			0 Months Ended	9 Months Ended	36 Months Ended
	Apr. 10, 2013	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Sep. 30, 2012 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Dec. 31, 2012 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Oct. 18, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	May 30, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Jul. 15, 2013 6.90% Series E-linked Preferred Units [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.	Sep. 30, 2013 6.90% Series E-linked Preferred Units [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.	Mar. 10, 2013 Offering Program [Member]	Mar. 10, 2013 Offering Program [Member] BRANDYWINE OPERATING PARTNERSHIP, L.P.
Earnings per Common Partnership Unit [Line Items]
Stock Issued During Period, Shares, New Issues	12,650,000
Additional shares granted under option to purchase in public offering	1,650,000
Proceeds from Issuance of Common Stock	$ 181,700	$ 181,527	$ 0		$ 181,527	$ 0
Distribution Declared Per Common Partnership Unit									$ 0.15
Distributions payable		25,579		23,652	25,579		23,652	23,800
Preferred Stock, Dividend Rate, Percentage		6.90%		6.90%	6.90%		6.90%				6.90%
Preferred Stock, Liquidation Preference Per Share											$ 25.00
Dividends, Preferred Stock, Cash		$ 5,175	$ 7,832							$ 1,700
Stock Issued During Period, Shares, Other												6,421,553	6,421,553
Average Sales Price Per Share												$ 12.50

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Segment Information

9 Months Ended

Sep. 30, 2013

Segment Reporting [Abstract]

Segment Reporting Disclosure [Text Block]

SEGMENT INFORMATION

As of September 30, 2013, the Company was managing its portfolio within seven geographic segments: (1) Pennsylvania, (2) Philadelphia Central Business District (CBD), (3) Metropolitan Washington D.C., (4) New Jersey/Delaware, (5) Richmond, Virginia, (6) Austin, Texas and (7) California. The Pennsylvania segment includes properties in Chester, Delaware, and Montgomery counties in the Philadelphia suburbs. The Philadelphia CBD segment includes properties located in the City of Philadelphia in Pennsylvania. The Metropolitan Washington, D.C. segment includes properties in Northern Virginia and southern Maryland. The New Jersey/Delaware segment includes properties in Burlington, Camden and Mercer counties in New Jersey and in New Castle county in the state of Delaware. The Richmond, Virginia segment includes properties primarily in Albemarle, Chesterfield, Goochland and Henrico counties and one property in Durham, North Carolina. The Austin, Texas segment includes properties in Austin. The California segment includes properties in Oakland, Concord, and Carlsbad, California. The corporate group is responsible for cash and investment management, development of certain real estate properties during the construction period, and certain other general support functions. Land held for development and construction in progress are transferred to operating properties by region upon completion of the associated construction or project.

Segment information is as follows (in thousands):

	Pennsylvania Suburbs		Philadelphia CBD		Metropolitan, D.C.		New Jersey/Delaware		Richmond, Virginia		Austin, Texas		California		Corporate			Total
As of September 30, 2013:
Real estate investments, at cost:
Operating properties	$	1,196,987	$	1,026,116	$	1,207,243	$	410,143	$	309,646	$	289,075	$	192,700	$	—		$	4,631,910
Construction-in-progress															52,702			52,702
Land inventory															94,097			94,097
As of December 31, 2012:
Real estate investments, at cost:
Operating properties	$	1,178,730	$	988,590	$	1,193,200	$	546,644	$	309,923	$	285,346	$	223,736	$	—		$	4,726,169
Construction-in-progress															48,950			48,950
Land inventory															102,439			102,439
For the three-months ended September 30, 2013:
Total revenue	$	39,268	$	35,891	$	29,320	$	16,171	$	8,640	$	9,937	$	4,632	$	(403	)	$	143,456
Property operating expenses, real estate taxes and third party management expenses	13,291		13,704		10,321		8,647		3,735		3,958		2,531		(19		)	56,168
Net operating income	$	25,977	$	22,187	$	18,999	$	7,524	$	4,905	$	5,979	$	2,101	$	(384	)	$	87,288
For the three-months ended September 30, 2012:
Total revenue	$	38,373	$	33,026	$	26,516	$	15,536	$	8,826	$	8,274	$	4,448	$	(479	)	$	134,520
Property operating expenses, real estate taxes and third party management expenses	13,463		12,432		10,638		7,930		3,761		3,485		2,362		(504		)	53,567
Net operating income	$	24,910	$	20,594	$	15,878	$	7,606	$	5,065	$	4,789	$	2,086	$	25		$	80,953
For the nine-months ended September 30, 2013:
Total revenue	$	114,730	$	107,957	$	85,889	$	47,449	$	26,359	$	29,067	$	13,773	$	(1,026	)	$	424,198
Property operating expenses, real estate taxes and third party management expenses	40,256		40,826		31,856		23,301		11,017		12,123		7,029		(75		)	166,333
Net operating income	$	74,474	$	67,131	$	54,033	$	24,148	$	15,342	$	16,944	$	6,744	$	(951	)	$	257,865
For the nine-months ended September 30, 2012:
Total revenue	$	113,110	$	98,086	$	79,919	$	46,550	$	26,762	$	23,957	$	13,034	$	(1,305	)	$	400,113
Property operating expenses, real estate taxes and third party management expenses	39,285		37,080		31,156		22,841		10,874		10,494		6,747		(1,274		)	157,203
Net operating income	$	73,825	$	61,006	$	48,763	$	23,709	$	15,888	$	13,463	$	6,287	$	(31	)	$	242,910

Net operating income (“NOI”) is defined as total revenue less property operating expenses, real estate taxes and third party management expenses. Segment NOI includes revenue, real estate taxes and property operating expenses directly related to operation and management of the properties owned and managed within the respective geographical region. Segment NOI excludes property level depreciation and amortization, revenue and expenses directly associated with third party real estate management services, expenses associated with corporate administrative support services, and inter-company eliminations. NOI also does not reflect general and administrative expenses, interest expenses, real estate impairment losses, depreciation and amortization costs, capital expenditures and leasing costs. Trends in development and construction activities that could materially impact the Company’s results from operations are also not reflected in NOI. All companies may not calculate NOI in the same manner. NOI is the measure that is used by the Company to evaluate the operating performance of its real estate assets by segment. The Company also believes that NOI provides useful information to investors regarding the Company's financial condition and results of operations because it reflects only those income and expenses recorded at the property level. The Company believes that net income, as defined by GAAP, is the most appropriate earnings measure. Below is a reconciliation of consolidated NOI to consolidated net income, as defined by GAAP:

	Three-month periods ended September 30,						Nine-month periods ended September 30,
	2013			2012			2013			2012
	(amounts in thousands)						(amounts in thousands)
Consolidated net operating income	$	87,288		$	80,953		$	257,865		$	242,910
Less:
Interest expense	(30,338		)	(32,620		)	(91,689		)	(99,745		)
Interest expense - amortization of deferred financing costs	(1,158		)	(1,218		)	(3,502		)	(3,790		)
Interest expense - financing obligation	(264		)	(230		)	(693		)	(608		)
Depreciation and amortization	(50,613		)	(46,955		)	(149,423		)	(142,262		)
General and administrative expenses	(6,436		)	(6,080		)	(20,322		)	(18,209		)
Net loss on sale of undepreciated real estate	(129		)	—			(129		)	—
Loss on real estate venture formation	—			(950		)	—			(950		)
Loss on early extinguishment of debt	(11		)	(51		)	(1,127		)	(1,549		)
Plus:
Interest income	268			311			448			2,631
Historic tax credit transaction income	11,853			11,840			11,853			11,840
Equity in income of real estate ventures	714			500			3,757			1,382
Gain from remeasurement of investment in a real estate venture	—			—			7,847			—
Net gain on real estate venture transactions	—			—			3,683			—
Income (loss) from continuing operations	11,174			5,500			18,568			(8,350		)
Income (loss) from discontinued operations	(86		)	11,589			3,619			41,577
Net income	$	11,088		$	17,089		$	22,187		$	33,227

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Consolidated Statements of Beneficiaries' Equity (USD $) In Thousands, except Share data	Total	Series E Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Deferred Compensation, Share-based Payments [Member]	Common Stock In Grantor Trust [Member]	Cumulative Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Cumulative Distributions [Member]	Noncontrolling Interest [Member]
Beginning Balance at Dec. 31, 2011	$ 1,889,696	$ 43	$ 1,424	$ 2,776,197	$ 5,631	$ (5,631)	$ 477,338	$ (6,079)	$ (1,392,332)	$ 33,105
Beginning Balance, shares at Dec. 31, 2011		4,300,000	142,690,755		292,646
Net income	33,227						32,804			423
Comprehensive Income (Loss)	(14,580)							(14,377)		(203)
Preferred Stock, Shares Issued		4,000,000
Preferred Stock, Value, Issued		40
Issuance of Preferred Shares	96,850			96,810
Equity Issuance Costs	(610)			(610)
Redemption of Preferred Shares, Shares		(2,000,000)
Redemption of Preferred Shares, Value	47,910	(20)		47,890
Conversion of LP Units to Common Shares, shares			20,464
Conversion of LP Units to Common Shares	(231)		1	149			(49)			(332)
Bonus Share Issuance, Shares			35,703
Bonus Share Issuance	387			387
Vesting of Restricted Shares, Shares			280,851		9,036
Vesting of Restricted Shares	(1,291)		3	(1,294)
Restricted Share Amortization	2,138			2,138
Vesting of Restricted Performance Units, Shares			249,797
Vesting of Restricted Performance Units	(1,329)		2	(1,331)
Restricted Performance Units Amortization	1,926			1,926
Exercise of Stock Options, Shares			165,159
Exercise of Stock Options	748		2	746
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition				1,121
Stock Option Amortization	1,121
Share Issuance from/to Deferred Compensation Plan, Shares			(5,564)		(10,937)
Share Issuance from/to Deferred Compensation Plan	0				(279)	279
Trustee Fees Paid in Shares, Shares			1,336
Trustee Fees Paid in Shares, Value	15			15
Adjustments to Non-controlling Interest	11			358						(347)
Preferred Share distributions	(7,832)								(7,832)
Preferred share redemption charge	(2,090)								(2,090)
Distributions declared ($0.15 per share)	(66,037)								(64,804)	(1,233)
Ending Balance at Sep. 30, 2012	1,884,209	63	1,432	2,828,722	5,352	(5,352)	510,093	(20,456)	(1,467,058)	31,413
Ending Balance, shares at Sep. 30, 2012		6,300,000	143,438,501		290,745
Beginning Balance at Dec. 31, 2012	1,773,516	40	1,434	2,780,194	5,352	(5,352)	479,734	(15,918)	(1,493,206)	21,238
Beginning Balance, shares at Dec. 31, 2012		4,000,000	143,538,733		290,745
Net income	22,187						21,992			195
Comprehensive Income (Loss)	10,210							10,093		117
Stock Issued During Period, Shares, New Issues			12,650,000
Issuance of Common Shares of Beneficial Interest, Value, New Issues	182,034		127	181,907
Preferred Stock, Shares Issued	4,000,000
Preferred Stock, Value, Issued	40
Equity Issuance Costs	(382)			(382)
Conversion of LP Units to Common Shares, shares			81,998
Conversion of LP Units to Common Shares	0		1	1,240						(1,241)
Bonus Share Issuance, Shares			27,918
Bonus Share Issuance	361			361
Vesting of Restricted Shares, Shares			147,495		7,050
Vesting of Restricted Shares	(902)		2	(904)
Restricted Share Amortization	2,565			2,565
Vesting of Restricted Performance Units, Shares			53,134		27,067
Vesting of Restricted Performance Units	(160)			(160)
Restricted Performance Units Amortization	3,718			3,718
Restricted Share Forfeitures	9						9
Exercise of Stock Options, Shares	207,941		207,941
Exercise of Stock Options	2,238		1	2,237
Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition				546
Stock Option Amortization	546
Share Issuance from/to Deferred Compensation Plan, Shares			(4,838)		(11,839)
Share Issuance from/to Deferred Compensation Plan	0				79	(79)
Trustee Fees Paid in Shares, Shares			1,409
Trustee Fees Paid in Shares, Value	20			20
Adjustments to Non-controlling Interest	0			(766)						766
Preferred Share distributions	(5,175)								(5,175)
Preferred share redemption charge	0
Distributions declared ($0.15 per share)	(69,627)								(68,821)	(806)
Ending Balance at Sep. 30, 2013	$ 1,921,158	$ 40	$ 1,565	$ 2,970,576	$ 5,431	$ (5,431)	$ 501,735	$ (5,825)	$ (1,567,202)	$ 20,269
Ending Balance, shares at Sep. 30, 2013		4,000,000	156,703,790		313,023

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Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Net income	$ 22,187	$ 33,227
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	151,066	150,362
Amortization of deferred financing costs	3,502	3,790
Amortization of debt discount/(premium), net	1,112	1,095
Amortization of stock compensation costs	5,510	3,740
Shares used for employee taxes upon vesting of share awards	(1,062)	(2,232)
Straight-line rent income	(16,337)	(17,792)
Amortization of acquired above (below) market leases to rental revenue, net	(5,372)	(4,468)
Straight-line ground rent expense	1,286	1,423
Provision for doubtful accounts	1,777	1,363
Net gain on sale of interests in real estate	(3,044)	(34,773)
Loss On Real Estate Venture Formation	0	950
Net gain on real estate venture transactions	(3,683)	0
Gain from remeasurement of investment in a real estate venture	(7,847)	0
Loss on early extinguishment of debt	1,127	1,549
Historic tax credit transaction income	(11,853)	(11,840)
Real estate venture income in excess of distributions	(2,371)	(1,024)
Deferred financing obligation	(1,392)	(1,314)
Changes in assets and liabilities:
Accounts receivable	(287)	1,580
Other assets	(5,758)	(7,200)
Accounts payable and accrued expenses	14,684	9,565
Increase (Decrease) in Leasing Receivables	1,265	(4,681)
Other liabilities	1,718	(1,175)
Net cash from operating activities	146,228	122,145
Cash flows from investing activities:
Acquisition of properties	(20,758)	(9,226)
Payments to acquire available-for-sale securities	0	(98,250)
Proceeds from Sale of Available-for-sale Securities	0	98,250
Sales of properties, net	145,931	170,918
Distribution of sales proceeds from real estate ventures	16,963	0
Proceeds from repayment of mortgage notes receivable	200	23,930
Capital expenditures for tenant improvements	(64,481)	(64,527)
Capital expenditures for redevelopments	(5,288)	(9,122)
Capital expenditures for developments	(5,399)	0
Reimbursement from real estate venture for pre-formation development costs	1,976	0
Advances for purchase of tenant assets, net of repayments	(420)	(13)
Investment in unconsolidated real estate ventures	(30,142)	(49,763)
Cash distributions from unconsolidated real estate ventures	3,661	2,779
Leasing costs	(25,704)	(22,111)
Net cash from investing activities	16,539	42,865
Cash flows from financing activities:
Proceeds from Unsecured Term Loans	0	600,000
Proceeds from Credit Facility borrowings	186,000	21,500
Repayments of Credit Facility borrowings	(255,000)	(297,000)
Repayments of mortgage notes payable	(8,351)	(9,209)
Deferred financing obligation non-cash interest expense	697	701
Proceeds from Issuance of Common Stock	181,527	0
Proceeds from Issuance of Preferred Stock and Preference Stock	0	96,240
Redemption of preferred shares	0	(50,188)
Repayments of unsecured notes	(13,027)	(167,841)
Repayments of unsecured term loan	0	(37,500)
Net settlement of hedge transactions	0	(74)
Debt financing costs	(6)	(8,462)
Exercise of stock options	2,240	748
Distributions paid to shareholders	(72,061)	(71,523)
Distributions to noncontrolling interest	(818)	(1,196)
Net cash from financing activities	21,201	76,196
Increase in cash and cash equivalents	183,968	241,206
Cash and cash equivalents at beginning of period	1,549	410
Cash and cash equivalents at end of period	185,517	241,616
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the nine months ended September 30, 2013 and 2012 of $2,012 and $1,978, respectively	76,528	83,618
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 operating real estate related to non-cash adjustment to land	(4,386)	0
Change in investments in real estate ventures related to a contribution of land	6,058	0
Change in capital expenditures financed through accounts payable at period end	1,210	(1,270)
Change in capital expenditures financed through retention payable at period end	(736)	284
Change in unfunded tenant allowance	(811)	(1,411)
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Net income	22,187	33,227
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	151,066	150,362
Amortization of deferred financing costs	3,502	3,790
Amortization of debt discount/(premium), net	1,112	1,095
Amortization of stock compensation costs	5,510	3,740
Shares used for employee taxes upon vesting of share awards	(1,062)	(2,232)
Straight-line rent income	(16,337)	(17,792)
Amortization of acquired above (below) market leases to rental revenue, net	(5,372)	(4,468)
Straight-line ground rent expense	1,286	1,423
Provision for doubtful accounts	1,777	1,363
Net gain on sale of interests in real estate	(3,044)	(34,773)
Loss On Real Estate Venture Formation	0	950
Net gain on real estate venture transactions	(3,683)	0
Gain from remeasurement of investment in a real estate venture	(7,847)	0
Loss on early extinguishment of debt	1,127	1,549
Historic tax credit transaction income	(11,853)	(11,840)
Real estate venture income in excess of distributions	(2,371)	(1,024)
Deferred financing obligation	(1,392)	(1,314)
Changes in assets and liabilities:
Accounts receivable	(287)	1,580
Other assets	(5,758)	(7,200)
Accounts payable and accrued expenses	14,684	9,565
Increase (Decrease) in Leasing Receivables	1,265	(4,681)
Other liabilities	1,718	(1,175)
Net cash from operating activities	146,228	122,145
Cash flows from investing activities:
Acquisition of properties	(20,758)	(9,226)
Payments to acquire available-for-sale securities	0	(98,250)
Proceeds from Sale of Available-for-sale Securities	0	98,250
Sales of properties, net	145,931	170,918
Distribution of sales proceeds from real estate ventures	16,963	0
Proceeds from repayment of mortgage notes receivable	200	23,930
Capital expenditures for tenant improvements	(64,481)	(64,527)
Capital expenditures for redevelopments	(5,288)	(9,122)
Capital expenditures for developments	(5,399)	0
Reimbursement from real estate venture for pre-formation development costs	1,976	0
Advances for purchase of tenant assets, net of repayments	(420)	(13)
Investment in unconsolidated real estate ventures	(30,142)	(49,763)
Cash distributions from unconsolidated real estate ventures	3,661	2,779
Leasing costs	(25,704)	(22,111)
Net cash from investing activities	16,539	42,865
Cash flows from financing activities:
Proceeds from Unsecured Term Loans	0	600,000
Proceeds from Credit Facility borrowings	186,000	21,500
Repayments of Credit Facility borrowings	(255,000)	(297,000)
Repayments of mortgage notes payable	(8,351)	(9,209)
Deferred financing obligation non-cash interest expense	697	701
Proceeds from Issuance of Common Stock	181,527	0
Proceeds from Issuance of Preferred Stock and Preference Stock	0	96,240
Redemption of preferred shares	0	(50,188)
Repayments of unsecured notes	(13,027)	(167,841)
Repayments of unsecured term loan	0	(37,500)
Net settlement of hedge transactions	0	(74)
Debt financing costs	(6)	(8,462)
Exercise of stock options	2,240	748
Distributions paid to shareholders	(72,879)	(72,719)
Net cash from financing activities	21,201	76,196
Increase in cash and cash equivalents	183,968	241,206
Cash and cash equivalents at beginning of period	1,549	410
Cash and cash equivalents at end of period	185,517	241,616
Supplemental disclosure:
Cash paid for interest, net of capitalized interest during the nine months ended September 30, 2013 and 2012 of $2,012 and $1,978, respectively	76,528	83,618
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 operating real estate related to non-cash adjustment to land	(4,386)	0
Change in investments in real estate ventures related to a contribution of land	6,058	0
Change in capital expenditures financed through accounts payable at period end	1,210	(1,270)
Change in capital expenditures financed through retention payable at period end	(736)	284
Change in unfunded tenant allowance	$ (811)	$ (1,411)

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Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Text Block]

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

Basis of Presentation

The consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, all adjustments (consisting solely of normal recurring matters) for a fair statement of the financial position of the Company as of September 30, 2013, the results of its operations for the three and nine-month periods ended September 30, 2013 and 2012 and its cash flows for the nine-month periods ended September 30, 2013 and 2012 have been included. The results of operations for such interim periods are not necessarily indicative of the results for a full year. These consolidated financial statements should be read in conjunction with the Parent Company’s and the Operating Partnership’s consolidated financial statements and footnotes included in their combined 2012 Annual Report on Form 10-K filed with the SEC on February 26, 2013.

Reclassifications

Certain amounts have been reclassified in prior years to conform to the current year presentation. The reclassifications are primarily due to the treatment of sold properties as discontinued operations on the statement of operations for all periods presented.

Principles of Consolidation

When the Company obtains an economic interest in an entity, the Company evaluates the entity to determine if the entity is deemed a variable interest entity (“VIE”), and if the Company is deemed to be the primary beneficiary, in accordance with the accounting standard for the consolidation of variable interest entities. The accounting standard for the consolidation of VIEs requires the Company to qualitatively assess if the Company was the primary beneficiary of the VIEs based on whether the Company had (i) the power to direct those matters that most significantly impacted the activities of the VIE and (ii) the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. For entities determined to be VIEs, but for which the Company is not the primary beneficiary, the Company's maximum exposure to loss is the carrying amount of its investments, as the Company has not provided any payment guarantees other than on approximately $0.6 million, as of September 30, 2013, of debt of the Real Estate Venture known as "PJP Building VII LC" and on the Company's share of the debt and potential cost overruns associated with the Real Estate Venture known as "evo at Cira Centre South Venture" (formerly referred to as the "Grove Venture"). Please refer to Note 4.

When an entity is not deemed to be a VIE, the Company considers the provisions of the same accounting standard to determine whether a general partner, or the general partners as a group, controls a limited partnership or similar entity when the limited partners have certain rights. The Company consolidates (i) entities that are VIEs and of which the Company is deemed to be the primary beneficiary and (ii) entities that are non-VIEs and controlled by the Company and in which the limited partners neither have the ability to dissolve the entity or remove the Company without cause nor any substantive participating rights. Entities that the Company accounts for under the equity method (i.e., at cost, increased or decreased by the Company’s share of earnings or losses, plus contributions, less distributions) include (i) entities that are VIEs and of which the Company is not deemed to be the primary beneficiary, (ii) entities that are non-VIEs which the Company does not control, but over which the Company has the ability to exercise significant influence, and (iii) entities that are non-VIEs that the Company controls through its general partner status, but the limited partners in the entity have the substantive ability to dissolve the entity or remove the Company without cause or have substantive participating rights. The Company continuously assesses its determination of whether an entity is a VIE and who the primary beneficiary is, and whether or not the limited partners in an entity have substantive rights, more particularly if certain events occur that are likely to cause a change in the original determinations. The Company’s assessment includes a review of applicable documents such as, but not limited to, applicable partnership agreements, LLC and other real estate venture agreements and management and leasing agreements to determine whether the Company has control to direct the business activities of the entities. The portion of the consolidated entities that is not owned by the Company is presented as non-controlling interest as of and during the periods consolidated. All intercompany accounts and transactions have been eliminated in consolidation.

On July 31, 2013, the Company formed a Real Estate Venture known as "4040 Wilson LLC Venture" (and referred to as "4040 Wilson") with an unaffiliated third party. Based upon the facts and circumstances at formation of 4040 Wilson, the Company determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and the Company's lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by the Company, and is accounted for under the equity method of accounting. Please refer to Note 4.

On January 25, 2013, the Company formed the evo at Cira Centre South Venture (formerly referred to as the "Grove Venture"), a Real Estate Venture with two unaffiliated third parties. Based upon the facts and circumstances at formation of the evo at Cira Centre South Venture, the Company determined that the evo at Cira Centre South Venture is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate the evo at Cira Centre South Venture. Based upon each member's shared power over the evo at Cira Centre South Venture activities under the operating and related agreements of the evo at Cira Centre South Venture, and the Company's lack of exclusive control over the development and construction phases of the project, the evo at Cira Centre South Venture is not consolidated by the Company and is accounted for under the equity method of accounting. For further information regarding the evo at Cira Centre South Venture and its formation, please refer to Note 4.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Management makes significant estimates regarding revenue, valuation of real estate and related intangible assets and liabilities, impairment of long-lived assets, allowance for doubtful accounts and deferred costs.

Operating Properties

Operating properties are carried at historical cost less accumulated depreciation and impairment losses. The cost of operating properties reflects their purchase price or development cost. Acquisition costs related to business combinations are expensed as incurred. Costs incurred for the renovation and betterment of an operating property are capitalized to the Company’s investment in that property. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. Fully-depreciated assets are removed from the accounts.

Purchase Price Allocation

The Company allocates the purchase price of properties to net tangible and identified intangible assets acquired based on fair values. Above-market and below-market in-place lease values for acquired properties are recorded based on the present value (using an interest rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to the in-place leases and (ii) the Company’s estimate of the fair market lease rates for the corresponding in-place leases, measured over a period equal to the remaining non-cancelable term of the lease (including the below market fixed renewal period, if applicable). Capitalized above-market lease values are amortized as a reduction of rental income over the remaining non-cancelable terms of the respective leases. Capitalized below-market lease values are amortized as an increase to rental income over the remaining non-cancelable terms of the respective leases, including any below market fixed-rate renewal periods.

Other intangible assets also include amounts representing the value of tenant relationships and in-place leases based on the Company’s evaluation of the specific characteristics of each tenant’s lease and the Company’s overall relationship with the respective tenant. The Company generally estimates the cost to execute leases with terms similar to the remaining lease terms of the in-place leases, including leasing commissions, legal and other related expenses. This intangible asset is generally amortized to expense over the remaining term of the respective leases and any fixed-rate bargain renewal periods. Company estimates of value are made using methods similar to those used by independent appraisers or by using independent appraisals. Factors considered by the Company in this analysis include an estimate of the carrying costs during the expected lease-up periods considering current market conditions and costs to execute similar leases. In estimating carrying costs, the Company includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, which primarily range from three to twelve months. The Company also considers information obtained about each property as a result of its pre-acquisition due diligence, marketing and leasing activities in estimating the fair value of the tangible and intangible assets acquired. The Company also uses the information obtained as a result of its pre-acquisition due diligence as part of its consideration of the accounting standard governing asset retirement obligations, and, when necessary, will record a conditional asset retirement obligation as part of its purchase price.

Characteristics considered by the Company in allocating value to its tenant relationships include the nature and extent of the Company’s business relationship with the tenant, growth prospects for developing new business with the tenant, the tenant’s credit quality and expectations of lease renewals, among other factors. The value of tenant relationship intangibles is generally amortized over the remaining initial lease term and expected renewals, but in no event longer than the remaining depreciable life of the building. The value of in-place leases is generally amortized over the remaining non-cancelable term of the respective leases and any fixed-rate renewal periods.

In the event that a tenant terminates its lease, the unamortized portion of each intangible, including in-place lease values and tenant relationship values, would be charged to expense and market rate adjustments (above or below) would be recorded to revenue.

Impairment or Disposal of Long-Lived Assets

The accounting standard for property, plant and equipment provides a single accounting model for long-lived assets classified as held-for-sale; defines the scope of businesses to be disposed of that qualify for reporting as discontinued operations; and affects the timing of recognizing losses on such operations.

The Company reviews long-lived assets whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The review of recoverability is based on an estimate of the future undiscounted cash flows (excluding interest charges) expected to result from the long-lived asset’s use and eventual disposition. These cash flows consider factors such as expected future operating income, trends and prospects, as well as the effects of leasing demand, competition and other factors. If impairment exists due to the inability to recover the carrying value of a long-lived asset, an impairment loss is recorded to the extent that the carrying value exceeds the estimated fair-value of the property. The Company is required to make subjective assessments as to whether there are impairments in the values of the investments in long-lived assets. These assessments have a direct impact on its net income because recording an impairment loss results in an immediate negative adjustment to net income. The evaluation of anticipated cash flows is highly subjective and is based in part on assumptions regarding future occupancy, rental rates and capital requirements that could differ materially from actual results in future periods. Although the Company’s strategy is generally to hold its properties over the long-term, the Company will selectively dispose of properties for strategic needs. If the Company’s strategy changes or market conditions otherwise dictate an earlier sale date, an impairment loss may be recognized to reduce the property to the lower of the carrying amount or fair value less costs to sell, and such loss could be material. If the Company determines that impairment has occurred and the assets are classified as held and used, the affected assets must be reduced to their fair-value.

Where properties have been identified as having a potential for sale, additional judgments are required related to the determination as to the appropriate period over which the undiscounted cash flows should include the operating cash flows and the amount included as the estimated residual value. Management determines the amounts to be included based on a probability weighted cash flow. This requires significant judgment. In some cases, the results of whether an impairment is indicated are sensitive to changes in assumptions input into the estimates, including the hold period until expected sale.

The Company determined during its impairment review for the three and nine-month periods ended September 30, 2013 and 2012, that no impairment charges were necessary.

Investments in Unconsolidated Real Estate Ventures

The Company accounts for its investments in unconsolidated Real Estate Ventures under the equity method of accounting as it is not the primary beneficiary (for VIEs) and the Company exercises significant influence, but does not control these entities under the provisions of the entities’ governing agreements pursuant to the accounting standard for the consolidation of VIEs. When the Company determines that its investment in an unconsolidated Real Estate Venture does not constitute a VIE, the Company utilizes the voting interest model under the accounting standard for consolidation to determine whether to consolidate the venture.

Under the equity method, investments in unconsolidated Real Estate Ventures are recorded initially at cost, as investments in Real Estate Ventures, and subsequently adjusted for equity in earnings, cash contributions, less distributions and impairments. On a periodic basis, management also assesses whether there are any indicators that the value of the Company’s investments in unconsolidated Real Estate Ventures may be other than temporarily impaired. An investment is impaired only if the value of the investment, as estimated by management, is less than the carrying value of the investment and the decline is other than temporary. To the extent that an impairment has occurred, the loss shall be measured as the excess of the carrying amount of the investment over the fair value of the investment, as estimated by management. The determination as to whether an impairment exists requires significant management judgment about the fair value of its ownership interest. Fair value is determined through various valuation techniques, including but not limited to, discounted cash flow models, quoted market values and third party appraisals.

When the Company acquires an interest in or contributes assets to a Real Estate Venture project, the difference between the Company’s cost basis in the investment and the value of the Real Estate Venture or asset contributed is amortized over the life of the related assets, intangibles and liabilities and such adjustment is included in the Company’s share of equity in income of unconsolidated Real Estate Ventures. For purposes of cash flow presentation, distributions from unconsolidated Real Estate Ventures are presented as part of operating activities when they are considered as return on investments. Distributions in excess of the Company’s share in the cumulative unconsolidated Real Estate Ventures’ earnings are considered as return of investments and are presented as part of investing activities in accordance with the accounting standard for cash flow presentation.

Revenue Recognition

Rental revenue is recognized on the straight-line basis, which averages minimum rents over the terms of the leases from the later of the date of the commencement of the lease or the date of acquisition of the property subject to existing leases. The straight-line rent adjustment increased revenue by approximately $4.5 million and $14.5 million for the three and nine-month periods ended September 30, 2013, and approximately $4.3 million and $16.0 million for the three and nine-month periods ended September 30, 2012, respectively. Deferred rents on the balance sheet represent rental revenue received prior to their due dates and amounts paid by the tenant for certain improvements considered to be landlord assets that will remain as the Company’s property at the end of the tenant’s lease term. The amortization of the amounts paid by the tenant for such improvements is calculated on a straight-line basis over the term of the tenant’s lease and is a component of straight-line rental income and increased revenue by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2013, and by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2012, respectively. Lease incentives, which are included as reductions of rental revenue in the accompanying consolidated statements of operations, are recognized on a straight-line basis over the term of the lease. Lease incentives decreased revenue by $0.2 million and $0.4 million for the three and nine-month periods ended September 30, 2013, and decreased revenue by $0.1 million and $0.6 million for the three and nine-month periods ended September 30, 2012, respectively.

Leases also typically provide for tenant reimbursement of a portion of common area maintenance and other operating expenses to the extent that a tenant’s pro rata share of expenses exceeds a base year level set in the lease or to the extent that the tenant has a lease on a triple net basis. For certain leases, significant assumptions and judgments are made by the Company in determining the lease term such as when termination options are provided to the tenant. The lease term impacts the period over which minimum rents are determined and recorded and also considers the period over which lease related costs are amortized. Termination fees received from tenants, bankruptcy settlement fees, third party management fees, labor reimbursement and leasing income are recorded when earned.

Stock-Based Compensation Plans

The Parent Company maintains a shareholder-approved equity-incentive plan known as the Amended and Restated 1997 Long-Term Incentive Plan (the “1997 Plan”). The 1997 Plan is administered by the Compensation Committee of the Parent Company’s Board of Trustees. Under the 1997 Plan, the Compensation Committee is authorized to award equity and equity-based awards, including incentive stock options, non-qualified stock options, restricted shares and performance-based shares. As of September 30, 2013, 5,195,177 common shares remained available for future awards under the 1997 Plan (including 3,011,946 shares available solely for options and share appreciation rights). Through September 30, 2013, all options awarded under the 1997 Plan had a one to ten-year term.

The Company incurred stock-based compensation expense of $2.3 million and $7.0 million during the three and nine-month periods ended September 30, 2013, of which $0.3 million and $1.1 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The Company incurred stock-based compensation expense of $1.8 million and $5.5 million during the three and nine-month periods ended September 30, 2012, of which $0.5 million and $1.4 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The expensed amounts are included in general and administrative expense on the Company’s consolidated income statement in the respective periods.

Accounting for Derivative Instruments and Hedging Activities

The Company accounts for its derivative instruments and hedging activities in accordance with the accounting standard for derivative and hedging activities. The accounting standard requires the Company to measure every derivative instrument (including certain derivative instruments embedded in other contracts) at fair value and record them in the balance sheet as either an asset or liability. See disclosures below related to the accounting standard for fair value measurements and disclosures.

For derivatives designated as cash flow hedges, the effective portions of changes in the fair value of the derivative are reported in other comprehensive income while the ineffective portions are recognized in earnings.

The Company actively manages its ratio of fixed-to-floating rate debt. To manage its fixed and floating rate debt in a cost-effective manner, the Company, from time to time, enters into interest rate swap agreements as cash flow hedges, under which it agrees to exchange various combinations of fixed and/or variable interest rates based on agreed upon notional amounts.

Fair Value Measurements

The Company estimates the fair value of its derivatives and available-for-sale securities in accordance with the accounting standard for fair value measurements and disclosures. The accounting standard defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. It also establishes a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value. Financial assets and liabilities recorded on the Consolidated Balance Sheets are categorized based on the inputs to the valuation techniques as follows:

• Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access;

• Level 2 inputs are inputs other than quoted prices included in Level 1, that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals; and

• Level 3 inputs are unobservable inputs for the asset or liability, which is typically based on an entity’s own assumptions, as there is little, if any, related market activity or information.

In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2013		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	112	$	—	$	112	$	—
Liabilities:
Interest Rate Swaps	$	4,314	$	—	$	4,314	$	—

The following table sets forth the Company’s financial liabilities that were accounted for at fair value on a recurring basis as of December 31, 2012 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2012		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	—	$	—	$	—	$	—
Liabilities:
Interest Rate Swaps	$	14,210	$	—	$	14,210	$	—

We classify our interest rate swaps, shown above, within Level 2 as the valuation inputs are based on quoted prices and market observable data of similar instruments.

Non-financial assets and liabilities recorded at fair value on a non-recurring basis to which the Company would apply the accounting standard where a measurement was required under fair value would include:

• Non-financial assets and liabilities initially measured at fair value in an acquisition or business combination that are not remeasured at least quarterly at fair value,

• Long-lived assets measured at fair value due to an impairment in accordance with the accounting standard for the impairment or disposal of long-lived assets,

• Equity and cost method investments measured at fair value due to an impairment in accordance with the accounting standard for investments,

• Notes receivable adjusted for any impairment in its value in accordance with the accounting standard for loan receivables, and

• Asset retirement obligations initially measured at fair value under the accounting standard for asset retirement obligations.

Other than the remeasurement of Six Tower Bridge (see Note 3), there were no items that were accounted for at fair value on a non-recurring basis for the nine months ended September 30, 2013.

Notes Receivable

As of September 30, 2013 and December 31, 2012, notes receivable included a purchase money mortgage with a 20-year amortization period bearing interest at 8.5%, which was valued at $7.0 million and $7.2 million, respectively. The borrower had previously defaulted on the note. As a result, a forbearance agreement dated October 2011, as amended by a second forbearance agreement dated July 9, 2013, was entered into between the Company and the borrower, outlining the repayment terms of the outstanding debt. The Company has determined that the loan modification represents a troubled debt restructuring due to the fact that the borrower was considered to be in a financial difficulty when it defaulted on the two mortgage debts, and that a concession was granted in the form of the forbearance agreements. In accordance with the accounting standard for loan receivables the Company performs, on an ongoing basis, a collectability assessment of the note using the expected cash flow information provided by the borrower. Based on cash flow projections provided by the borrower, the note will be fully paid during 2015. As of September 30, 2013, the present value of the expected cash flows of the note receivable exceeded the outstanding balance of the note and therefore the note is recoverable as of September 30, 2013.

Income Taxes

Parent Company

The Parent Company has elected to be treated as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). In order to continue to qualify as a REIT, the Parent Company is required to, among other things, distribute at least 90% of its annual REIT taxable income to its shareholders and meet certain tests regarding the nature of its income and assets. As a REIT, the Parent Company is not subject to federal and state income taxes with respect to the portion of its income that meets certain criteria and is distributed annually to its shareholders. Accordingly, no provision for federal and state income taxes is included in the accompanying consolidated financial statements with respect to the operations of the Parent Company. The Parent Company intends to continue to operate in a manner that allows it to meet the requirements for taxation as a REIT. If the Parent Company fails to qualify as a REIT in any taxable year, it will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent tax years. The Parent Company is subject to certain local income taxes. Provision for such taxes has been included in general and administrative expenses in the Parent Company’s Consolidated Statements of Operations and Comprehensive Income.

The Parent Company has elected to treat several of its subsidiaries as taxable REIT subsidiaries (each a “TRS”). A TRS is subject to federal, state and local income tax. In general, a TRS may perform non-customary services for tenants, hold assets that the Parent Company, as a REIT, cannot hold directly and generally may engage in any real estate or non-real estate related business.

Operating Partnership

In general, the Operating Partnership is not subject to federal and state income taxes, and accordingly, no provision for income taxes has been made in the accompanying consolidated financial statements. The partners of the Operating Partnership are required to include their respective share of the Operating Partnership’s profits or losses in their respective tax returns. The Operating Partnership’s tax returns and the amount of allocable Partnership profits and losses are subject to examination by federal and state taxing authorities. If such examination results in changes to the Operating Partnership profits or losses, then the tax liability of the partners would be changed accordingly.

The Operating Partnership may elect to treat one or more of its subsidiaries as REITs under Sections 856 through 860 of the Code. Each subsidiary REIT has met the requirements for treatment as a REIT under Sections 856 through 860 of the Code, and, accordingly, no provision has been made for federal and state income taxes in the accompanying consolidated financial statements. If any subsidiary REIT fails to qualify as a REIT in any taxable year, that subsidiary REIT will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent taxable years. Also, each subsidiary REIT may be subject to certain local income taxes.

The Operating Partnership has elected to treat several of its subsidiaries as taxable TRSs, which are subject to federal, state and local income tax.

Recent Accounting Pronouncements

In February 2013, the Financial Accounting Standards Board (FASB) issued an amendment to the accounting standard for the presentation of comprehensive income. This amendment requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component, and represents the culmination of the FASB's redeliberation on the reporting of such reclassification adjustments. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income, but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. This update is effective for fiscal years and interim periods beginning after December 15, 2012. The Company’s adoption of the accounting standard did not have a material impact on its consolidated financial position or results of operations as the update relates only to changes in financial statement presentation.

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Tax Credit Transactions Tax Credit Transactions (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Historic Tax Credit Transaction [Member]	Sep. 30, 2012 Historic Tax Credit Transaction [Member]	Sep. 30, 2013 Historic Tax Credit Transaction [Member]	Sep. 30, 2012 Historic Tax Credit Transaction [Member]	Dec. 31, 2012 Historic Tax Credit Transaction [Member]	Nov. 17, 2008 Historic Tax Credit Transaction [Member] sqft	Sep. 30, 2013 New Markets Tax Credit Transaction [Member]	Sep. 30, 2013 U S B [Member] Historic Tax Credit Transaction [Member]	Dec. 31, 2012 U S B [Member] Historic Tax Credit Transaction [Member]	Aug. 27, 2010 U S B [Member] Historic Tax Credit Transaction [Member]	Sep. 30, 2013 U S B [Member] New Markets Tax Credit Transaction [Member]	Dec. 31, 2012 U S B [Member] New Markets Tax Credit Transaction [Member]
Tax Credit Carryforward [Line Items]
Tax Credit Carryforward, Description											100% recapture for a period of seven years as provided in the Internal Revenue Code
Area Of Irs Campus Building										862,692
Percentage Of Building Leased To Irs										100.00%
Agreed contribution in project cost														$ 64,100,000
Percentage Of Tax Credit Recapture							20.00%				100.00%
Deferred Revenue												26,800,000	39,100,000		13,300,000	13,300,000
Contribution allocated in non controlling interest					2,700,000		2,700,000		2,600,000
Recognition Of Cash Received As Revenue Net Of Allocated Expenses							over the five year credit recapture period as defined in the Internal Revenue Code
Historic tax credit transaction income	(11,853,000)	(11,840,000)	(11,853,000)	(11,840,000)			(11,853,000)
Accretion Of Non Controlling Interest Liability					300,000	300,000	1,000,000	1,000,000
Expected benefit from qualified program											7,800,000
Percentage Of Qualified Investments											39.00%
Deferred costs, net					$ 1,000,000		$ 1,000,000		$ 1,600,000		$ 5,300,000					$ 5,300,000
Rate Of Return On Noncontrolling Interest									2.00%
Limit on tax credit claims under the Community Renewal Tax Relief											up to 39% of qualified investments in qualified, active low-income businesses or ventures
Recognition Of Cash Received As Revenue Net Of Allocated Expenses, Period Credit Recapture in Years							5 years				7 years

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Consolidated Statements of Cash Flows Consolidated Statement of Cash Flows (Parentheticals) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Supplemental Cash Flow Information [Abstract]
Capitalized interest	$ 2,012	$ 1,978
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Supplemental Cash Flow Information [Abstract]
Capitalized interest	$ 2,012	$ 1,978

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Segment Information Segment Information (Tables)

9 Months Ended

Sep. 30, 2013

Segment Reporting [Abstract]

Schedule of Segment Reporting Information, by Segment [Table Text Block]

Segment information is as follows (in thousands):

	Pennsylvania Suburbs		Philadelphia CBD		Metropolitan, D.C.		New Jersey/Delaware		Richmond, Virginia		Austin, Texas		California		Corporate			Total
As of September 30, 2013:
Real estate investments, at cost:
Operating properties	$	1,196,987	$	1,026,116	$	1,207,243	$	410,143	$	309,646	$	289,075	$	192,700	$	—		$	4,631,910
Construction-in-progress															52,702			52,702
Land inventory															94,097			94,097
As of December 31, 2012:
Real estate investments, at cost:
Operating properties	$	1,178,730	$	988,590	$	1,193,200	$	546,644	$	309,923	$	285,346	$	223,736	$	—		$	4,726,169
Construction-in-progress															48,950			48,950
Land inventory															102,439			102,439
For the three-months ended September 30, 2013:
Total revenue	$	39,268	$	35,891	$	29,320	$	16,171	$	8,640	$	9,937	$	4,632	$	(403	)	$	143,456
Property operating expenses, real estate taxes and third party management expenses	13,291		13,704		10,321		8,647		3,735		3,958		2,531		(19		)	56,168
Net operating income	$	25,977	$	22,187	$	18,999	$	7,524	$	4,905	$	5,979	$	2,101	$	(384	)	$	87,288
For the three-months ended September 30, 2012:
Total revenue	$	38,373	$	33,026	$	26,516	$	15,536	$	8,826	$	8,274	$	4,448	$	(479	)	$	134,520
Property operating expenses, real estate taxes and third party management expenses	13,463		12,432		10,638		7,930		3,761		3,485		2,362		(504		)	53,567
Net operating income	$	24,910	$	20,594	$	15,878	$	7,606	$	5,065	$	4,789	$	2,086	$	25		$	80,953
For the nine-months ended September 30, 2013:
Total revenue	$	114,730	$	107,957	$	85,889	$	47,449	$	26,359	$	29,067	$	13,773	$	(1,026	)	$	424,198
Property operating expenses, real estate taxes and third party management expenses	40,256		40,826		31,856		23,301		11,017		12,123		7,029		(75		)	166,333
Net operating income	$	74,474	$	67,131	$	54,033	$	24,148	$	15,342	$	16,944	$	6,744	$	(951	)	$	257,865
For the nine-months ended September 30, 2012:
Total revenue	$	113,110	$	98,086	$	79,919	$	46,550	$	26,762	$	23,957	$	13,034	$	(1,305	)	$	400,113
Property operating expenses, real estate taxes and third party management expenses	39,285		37,080		31,156		22,841		10,874		10,494		6,747		(1,274		)	157,203
Net operating income	$	73,825	$	61,006	$	48,763	$	23,709	$	15,888	$	13,463	$	6,287	$	(31	)	$	242,910

Reconciliation Of Consolidated Net Operating Income [Table Text Block]

	Three-month periods ended September 30,						Nine-month periods ended September 30,
	2013			2012			2013			2012
	(amounts in thousands)						(amounts in thousands)
Consolidated net operating income	$	87,288		$	80,953		$	257,865		$	242,910
Less:
Interest expense	(30,338		)	(32,620		)	(91,689		)	(99,745		)
Interest expense - amortization of deferred financing costs	(1,158		)	(1,218		)	(3,502		)	(3,790		)
Interest expense - financing obligation	(264		)	(230		)	(693		)	(608		)
Depreciation and amortization	(50,613		)	(46,955		)	(149,423		)	(142,262		)
General and administrative expenses	(6,436		)	(6,080		)	(20,322		)	(18,209		)
Net loss on sale of undepreciated real estate	(129		)	—			(129		)	—
Loss on real estate venture formation	—			(950		)	—			(950		)
Loss on early extinguishment of debt	(11		)	(51		)	(1,127		)	(1,549		)
Plus:
Interest income	268			311			448			2,631
Historic tax credit transaction income	11,853			11,840			11,853			11,840
Equity in income of real estate ventures	714			500			3,757			1,382
Gain from remeasurement of investment in a real estate venture	—			—			7,847			—
Net gain on real estate venture transactions	—			—			3,683			—
Income (loss) from continuing operations	11,174			5,500			18,568			(8,350		)
Income (loss) from discontinued operations	(86		)	11,589			3,619			41,577
Net income	$	11,088		$	17,089		$	22,187		$	33,227

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Summary of Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation

The consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in the financial statements prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, all adjustments (consisting solely of normal recurring matters) for a fair statement of the financial position of the Company as of September 30, 2013, the results of its operations for the three and nine-month periods ended September 30, 2013 and 2012 and its cash flows for the nine-month periods ended September 30, 2013 and 2012 have been included. The results of operations for such interim periods are not necessarily indicative of the results for a full year. These consolidated financial statements should be read in conjunction with the Parent Company’s and the Operating Partnership’s consolidated financial statements and footnotes included in their combined 2012 Annual Report on Form 10-K filed with the SEC on February 26, 2013.

Reclassification, Policy [Policy Text Block]

Reclassifications

Certain amounts have been reclassified in prior years to conform to the current year presentation. The reclassifications are primarily due to the treatment of sold properties as discontinued operations on the statement of operations for all periods presented.

Principles of Consolidation, Policy [Policy Text Block]

Principles of Consolidation

When the Company obtains an economic interest in an entity, the Company evaluates the entity to determine if the entity is deemed a variable interest entity (“VIE”), and if the Company is deemed to be the primary beneficiary, in accordance with the accounting standard for the consolidation of variable interest entities. The accounting standard for the consolidation of VIEs requires the Company to qualitatively assess if the Company was the primary beneficiary of the VIEs based on whether the Company had (i) the power to direct those matters that most significantly impacted the activities of the VIE and (ii) the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. For entities determined to be VIEs, but for which the Company is not the primary beneficiary, the Company's maximum exposure to loss is the carrying amount of its investments, as the Company has not provided any payment guarantees other than on approximately $0.6 million, as of September 30, 2013, of debt of the Real Estate Venture known as "PJP Building VII LC" and on the Company's share of the debt and potential cost overruns associated with the Real Estate Venture known as "evo at Cira Centre South Venture" (formerly referred to as the "Grove Venture"). Please refer to Note 4.

When an entity is not deemed to be a VIE, the Company considers the provisions of the same accounting standard to determine whether a general partner, or the general partners as a group, controls a limited partnership or similar entity when the limited partners have certain rights. The Company consolidates (i) entities that are VIEs and of which the Company is deemed to be the primary beneficiary and (ii) entities that are non-VIEs and controlled by the Company and in which the limited partners neither have the ability to dissolve the entity or remove the Company without cause nor any substantive participating rights. Entities that the Company accounts for under the equity method (i.e., at cost, increased or decreased by the Company’s share of earnings or losses, plus contributions, less distributions) include (i) entities that are VIEs and of which the Company is not deemed to be the primary beneficiary, (ii) entities that are non-VIEs which the Company does not control, but over which the Company has the ability to exercise significant influence, and (iii) entities that are non-VIEs that the Company controls through its general partner status, but the limited partners in the entity have the substantive ability to dissolve the entity or remove the Company without cause or have substantive participating rights. The Company continuously assesses its determination of whether an entity is a VIE and who the primary beneficiary is, and whether or not the limited partners in an entity have substantive rights, more particularly if certain events occur that are likely to cause a change in the original determinations. The Company’s assessment includes a review of applicable documents such as, but not limited to, applicable partnership agreements, LLC and other real estate venture agreements and management and leasing agreements to determine whether the Company has control to direct the business activities of the entities. The portion of the consolidated entities that is not owned by the Company is presented as non-controlling interest as of and during the periods consolidated. All intercompany accounts and transactions have been eliminated in consolidation.

On July 31, 2013, the Company formed a Real Estate Venture known as "4040 Wilson LLC Venture" (and referred to as "4040 Wilson") with an unaffiliated third party. Based upon the facts and circumstances at formation of 4040 Wilson, the Company determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and the Company's lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by the Company, and is accounted for under the equity method of accounting. Please refer to Note 4.

On January 25, 2013, the Company formed the evo at Cira Centre South Venture (formerly referred to as the "Grove Venture"), a Real Estate Venture with two unaffiliated third parties. Based upon the facts and circumstances at formation of the evo at Cira Centre South Venture, the Company determined that the evo at Cira Centre South Venture is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate the evo at Cira Centre South Venture. Based upon each member's shared power over the evo at Cira Centre South Venture activities under the operating and related agreements of the evo at Cira Centre South Venture, and the Company's lack of exclusive control over the development and construction phases of the project, the evo at Cira Centre South Venture is not consolidated by the Company and is accounted for under the equity method of accounting. For further information regarding the evo at Cira Centre South Venture and its formation, please refer to Note 4.

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Management makes significant estimates regarding revenue, valuation of real estate and related intangible assets and liabilities, impairment of long-lived assets, allowance for doubtful accounts and deferred costs.

Property, Plant and Equipment, Policy [Policy Text Block]

Operating Properties

Operating properties are carried at historical cost less accumulated depreciation and impairment losses. The cost of operating properties reflects their purchase price or development cost. Acquisition costs related to business combinations are expensed as incurred. Costs incurred for the renovation and betterment of an operating property are capitalized to the Company’s investment in that property. Ordinary repairs and maintenance are expensed as incurred; major replacements and betterments, which improve or extend the life of the asset, are capitalized and depreciated over their estimated useful lives. Fully-depreciated assets are removed from the accounts.

Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block]

Purchase Price Allocation

The Company allocates the purchase price of properties to net tangible and identified intangible assets acquired based on fair values. Above-market and below-market in-place lease values for acquired properties are recorded based on the present value (using an interest rate which reflects the risks associated with the leases acquired) of the difference between (i) the contractual amounts to be paid pursuant to the in-place leases and (ii) the Company’s estimate of the fair market lease rates for the corresponding in-place leases, measured over a period equal to the remaining non-cancelable term of the lease (including the below market fixed renewal period, if applicable). Capitalized above-market lease values are amortized as a reduction of rental income over the remaining non-cancelable terms of the respective leases. Capitalized below-market lease values are amortized as an increase to rental income over the remaining non-cancelable terms of the respective leases, including any below market fixed-rate renewal periods.

Other intangible assets also include amounts representing the value of tenant relationships and in-place leases based on the Company’s evaluation of the specific characteristics of each tenant’s lease and the Company’s overall relationship with the respective tenant. The Company generally estimates the cost to execute leases with terms similar to the remaining lease terms of the in-place leases, including leasing commissions, legal and other related expenses. This intangible asset is generally amortized to expense over the remaining term of the respective leases and any fixed-rate bargain renewal periods. Company estimates of value are made using methods similar to those used by independent appraisers or by using independent appraisals. Factors considered by the Company in this analysis include an estimate of the carrying costs during the expected lease-up periods considering current market conditions and costs to execute similar leases. In estimating carrying costs, the Company includes real estate taxes, insurance and other operating expenses and estimates of lost rentals at market rates during the expected lease-up periods, which primarily range from three to twelve months. The Company also considers information obtained about each property as a result of its pre-acquisition due diligence, marketing and leasing activities in estimating the fair value of the tangible and intangible assets acquired. The Company also uses the information obtained as a result of its pre-acquisition due diligence as part of its consideration of the accounting standard governing asset retirement obligations, and, when necessary, will record a conditional asset retirement obligation as part of its purchase price.

Characteristics considered by the Company in allocating value to its tenant relationships include the nature and extent of the Company’s business relationship with the tenant, growth prospects for developing new business with the tenant, the tenant’s credit quality and expectations of lease renewals, among other factors. The value of tenant relationship intangibles is generally amortized over the remaining initial lease term and expected renewals, but in no event longer than the remaining depreciable life of the building. The value of in-place leases is generally amortized over the remaining non-cancelable term of the respective leases and any fixed-rate renewal periods.

In the event that a tenant terminates its lease, the unamortized portion of each intangible, including in-place lease values and tenant relationship values, would be charged to expense and market rate adjustments (above or below) would be recorded to revenue.

Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]

Impairment or Disposal of Long-Lived Assets

The accounting standard for property, plant and equipment provides a single accounting model for long-lived assets classified as held-for-sale; defines the scope of businesses to be disposed of that qualify for reporting as discontinued operations; and affects the timing of recognizing losses on such operations.

The Company reviews long-lived assets whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. The review of recoverability is based on an estimate of the future undiscounted cash flows (excluding interest charges) expected to result from the long-lived asset’s use and eventual disposition. These cash flows consider factors such as expected future operating income, trends and prospects, as well as the effects of leasing demand, competition and other factors. If impairment exists due to the inability to recover the carrying value of a long-lived asset, an impairment loss is recorded to the extent that the carrying value exceeds the estimated fair-value of the property. The Company is required to make subjective assessments as to whether there are impairments in the values of the investments in long-lived assets. These assessments have a direct impact on its net income because recording an impairment loss results in an immediate negative adjustment to net income. The evaluation of anticipated cash flows is highly subjective and is based in part on assumptions regarding future occupancy, rental rates and capital requirements that could differ materially from actual results in future periods. Although the Company’s strategy is generally to hold its properties over the long-term, the Company will selectively dispose of properties for strategic needs. If the Company’s strategy changes or market conditions otherwise dictate an earlier sale date, an impairment loss may be recognized to reduce the property to the lower of the carrying amount or fair value less costs to sell, and such loss could be material. If the Company determines that impairment has occurred and the assets are classified as held and used, the affected assets must be reduced to their fair-value.

Where properties have been identified as having a potential for sale, additional judgments are required related to the determination as to the appropriate period over which the undiscounted cash flows should include the operating cash flows and the amount included as the estimated residual value. Management determines the amounts to be included based on a probability weighted cash flow. This requires significant judgment. In some cases, the results of whether an impairment is indicated are sensitive to changes in assumptions input into the estimates, including the hold period until expected sale.

The Company determined during its impairment review for the three and nine-month periods ended September 30, 2013 and 2012, that no impairment charges were necessary.

Equity Method Investments, Policy [Policy Text Block]

Investments in Unconsolidated Real Estate Ventures

The Company accounts for its investments in unconsolidated Real Estate Ventures under the equity method of accounting as it is not the primary beneficiary (for VIEs) and the Company exercises significant influence, but does not control these entities under the provisions of the entities’ governing agreements pursuant to the accounting standard for the consolidation of VIEs. When the Company determines that its investment in an unconsolidated Real Estate Venture does not constitute a VIE, the Company utilizes the voting interest model under the accounting standard for consolidation to determine whether to consolidate the venture.

Under the equity method, investments in unconsolidated Real Estate Ventures are recorded initially at cost, as investments in Real Estate Ventures, and subsequently adjusted for equity in earnings, cash contributions, less distributions and impairments. On a periodic basis, management also assesses whether there are any indicators that the value of the Company’s investments in unconsolidated Real Estate Ventures may be other than temporarily impaired. An investment is impaired only if the value of the investment, as estimated by management, is less than the carrying value of the investment and the decline is other than temporary. To the extent that an impairment has occurred, the loss shall be measured as the excess of the carrying amount of the investment over the fair value of the investment, as estimated by management. The determination as to whether an impairment exists requires significant management judgment about the fair value of its ownership interest. Fair value is determined through various valuation techniques, including but not limited to, discounted cash flow models, quoted market values and third party appraisals.

When the Company acquires an interest in or contributes assets to a Real Estate Venture project, the difference between the Company’s cost basis in the investment and the value of the Real Estate Venture or asset contributed is amortized over the life of the related assets, intangibles and liabilities and such adjustment is included in the Company’s share of equity in income of unconsolidated Real Estate Ventures. For purposes of cash flow presentation, distributions from unconsolidated Real Estate Ventures are presented as part of operating activities when they are considered as return on investments. Distributions in excess of the Company’s share in the cumulative unconsolidated Real Estate Ventures’ earnings are considered as return of investments and are presented as part of investing activities in accordance with the accounting standard for cash flow presentation.

Revenue Recognition, Policy [Policy Text Block]

Revenue Recognition

Rental revenue is recognized on the straight-line basis, which averages minimum rents over the terms of the leases from the later of the date of the commencement of the lease or the date of acquisition of the property subject to existing leases. The straight-line rent adjustment increased revenue by approximately $4.5 million and $14.5 million for the three and nine-month periods ended September 30, 2013, and approximately $4.3 million and $16.0 million for the three and nine-month periods ended September 30, 2012, respectively. Deferred rents on the balance sheet represent rental revenue received prior to their due dates and amounts paid by the tenant for certain improvements considered to be landlord assets that will remain as the Company’s property at the end of the tenant’s lease term. The amortization of the amounts paid by the tenant for such improvements is calculated on a straight-line basis over the term of the tenant’s lease and is a component of straight-line rental income and increased revenue by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2013, and by $0.6 million and $1.8 million for the three and nine-month periods ended September 30, 2012, respectively. Lease incentives, which are included as reductions of rental revenue in the accompanying consolidated statements of operations, are recognized on a straight-line basis over the term of the lease. Lease incentives decreased revenue by $0.2 million and $0.4 million for the three and nine-month periods ended September 30, 2013, and decreased revenue by $0.1 million and $0.6 million for the three and nine-month periods ended September 30, 2012, respectively.

Leases also typically provide for tenant reimbursement of a portion of common area maintenance and other operating expenses to the extent that a tenant’s pro rata share of expenses exceeds a base year level set in the lease or to the extent that the tenant has a lease on a triple net basis. For certain leases, significant assumptions and judgments are made by the Company in determining the lease term such as when termination options are provided to the tenant. The lease term impacts the period over which minimum rents are determined and recorded and also considers the period over which lease related costs are amortized. Termination fees received from tenants, bankruptcy settlement fees, third party management fees, labor reimbursement and leasing income are recorded when earned.

Stock-Based Compensation, Policy [Policy Text Block]

Stock-Based Compensation Plans

The Parent Company maintains a shareholder-approved equity-incentive plan known as the Amended and Restated 1997 Long-Term Incentive Plan (the “1997 Plan”). The 1997 Plan is administered by the Compensation Committee of the Parent Company’s Board of Trustees. Under the 1997 Plan, the Compensation Committee is authorized to award equity and equity-based awards, including incentive stock options, non-qualified stock options, restricted shares and performance-based shares. As of September 30, 2013, 5,195,177 common shares remained available for future awards under the 1997 Plan (including 3,011,946 shares available solely for options and share appreciation rights). Through September 30, 2013, all options awarded under the 1997 Plan had a one to ten-year term.

The Company incurred stock-based compensation expense of $2.3 million and $7.0 million during the three and nine-month periods ended September 30, 2013, of which $0.3 million and $1.1 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The Company incurred stock-based compensation expense of $1.8 million and $5.5 million during the three and nine-month periods ended September 30, 2012, of which $0.5 million and $1.4 million, respectively, were capitalized as part of the Company’s review of employee compensation costs eligible for capitalization. The expensed amounts are included in general and administrative expense on the Company’s consolidated income statement in the respective periods.

Derivatives, Policy [Policy Text Block]

Accounting for Derivative Instruments and Hedging Activities

The Company accounts for its derivative instruments and hedging activities in accordance with the accounting standard for derivative and hedging activities. The accounting standard requires the Company to measure every derivative instrument (including certain derivative instruments embedded in other contracts) at fair value and record them in the balance sheet as either an asset or liability. See disclosures below related to the accounting standard for fair value measurements and disclosures.

For derivatives designated as cash flow hedges, the effective portions of changes in the fair value of the derivative are reported in other comprehensive income while the ineffective portions are recognized in earnings.

The Company actively manages its ratio of fixed-to-floating rate debt. To manage its fixed and floating rate debt in a cost-effective manner, the Company, from time to time, enters into interest rate swap agreements as cash flow hedges, under which it agrees to exchange various combinations of fixed and/or variable interest rates based on agreed upon notional amounts.

Fair Value of Financial Instruments, Policy [Policy Text Block]

Fair Value Measurements

The Company estimates the fair value of its derivatives and available-for-sale securities in accordance with the accounting standard for fair value measurements and disclosures. The accounting standard defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. It also establishes a fair value hierarchy which requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The standard describes three levels of inputs that may be used to measure fair value. Financial assets and liabilities recorded on the Consolidated Balance Sheets are categorized based on the inputs to the valuation techniques as follows:

• Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access;

• Level 2 inputs are inputs other than quoted prices included in Level 1, that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals; and

• Level 3 inputs are unobservable inputs for the asset or liability, which is typically based on an entity’s own assumptions, as there is little, if any, related market activity or information.

In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2013		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	112	$	—	$	112	$	—
Liabilities:
Interest Rate Swaps	$	4,314	$	—	$	4,314	$	—

The following table sets forth the Company’s financial liabilities that were accounted for at fair value on a recurring basis as of December 31, 2012 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2012		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	—	$	—	$	—	$	—
Liabilities:
Interest Rate Swaps	$	14,210	$	—	$	14,210	$	—

We classify our interest rate swaps, shown above, within Level 2 as the valuation inputs are based on quoted prices and market observable data of similar instruments.

Non-financial assets and liabilities recorded at fair value on a non-recurring basis to which the Company would apply the accounting standard where a measurement was required under fair value would include:

• Non-financial assets and liabilities initially measured at fair value in an acquisition or business combination that are not remeasured at least quarterly at fair value,

• Long-lived assets measured at fair value due to an impairment in accordance with the accounting standard for the impairment or disposal of long-lived assets,

• Equity and cost method investments measured at fair value due to an impairment in accordance with the accounting standard for investments,

• Notes receivable adjusted for any impairment in its value in accordance with the accounting standard for loan receivables, and

• Asset retirement obligations initially measured at fair value under the accounting standard for asset retirement obligations.

Other than the remeasurement of Six Tower Bridge (see Note 3), there were no items that were accounted for at fair value on a non-recurring basis for the nine months ended September 30, 2013.

Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]

Notes Receivable

As of September 30, 2013 and December 31, 2012, notes receivable included a purchase money mortgage with a 20-year amortization period bearing interest at 8.5%, which was valued at $7.0 million and $7.2 million, respectively. The borrower had previously defaulted on the note. As a result, a forbearance agreement dated October 2011, as amended by a second forbearance agreement dated July 9, 2013, was entered into between the Company and the borrower, outlining the repayment terms of the outstanding debt. The Company has determined that the loan modification represents a troubled debt restructuring due to the fact that the borrower was considered to be in a financial difficulty when it defaulted on the two mortgage debts, and that a concession was granted in the form of the forbearance agreements. In accordance with the accounting standard for loan receivables the Company performs, on an ongoing basis, a collectability assessment of the note using the expected cash flow information provided by the borrower. Based on cash flow projections provided by the borrower, the note will be fully paid during 2015. As of September 30, 2013, the present value of the expected cash flows of the note receivable exceeded the outstanding balance of the note and therefore the note is recoverable as of September 30, 2013.

Income Tax, Policy [Policy Text Block]

Income Taxes

Parent Company

The Parent Company has elected to be treated as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). In order to continue to qualify as a REIT, the Parent Company is required to, among other things, distribute at least 90% of its annual REIT taxable income to its shareholders and meet certain tests regarding the nature of its income and assets. As a REIT, the Parent Company is not subject to federal and state income taxes with respect to the portion of its income that meets certain criteria and is distributed annually to its shareholders. Accordingly, no provision for federal and state income taxes is included in the accompanying consolidated financial statements with respect to the operations of the Parent Company. The Parent Company intends to continue to operate in a manner that allows it to meet the requirements for taxation as a REIT. If the Parent Company fails to qualify as a REIT in any taxable year, it will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent tax years. The Parent Company is subject to certain local income taxes. Provision for such taxes has been included in general and administrative expenses in the Parent Company’s Consolidated Statements of Operations and Comprehensive Income.

The Parent Company has elected to treat several of its subsidiaries as taxable REIT subsidiaries (each a “TRS”). A TRS is subject to federal, state and local income tax. In general, a TRS may perform non-customary services for tenants, hold assets that the Parent Company, as a REIT, cannot hold directly and generally may engage in any real estate or non-real estate related business.

Operating Partnership

In general, the Operating Partnership is not subject to federal and state income taxes, and accordingly, no provision for income taxes has been made in the accompanying consolidated financial statements. The partners of the Operating Partnership are required to include their respective share of the Operating Partnership’s profits or losses in their respective tax returns. The Operating Partnership’s tax returns and the amount of allocable Partnership profits and losses are subject to examination by federal and state taxing authorities. If such examination results in changes to the Operating Partnership profits or losses, then the tax liability of the partners would be changed accordingly.

The Operating Partnership may elect to treat one or more of its subsidiaries as REITs under Sections 856 through 860 of the Code. Each subsidiary REIT has met the requirements for treatment as a REIT under Sections 856 through 860 of the Code, and, accordingly, no provision has been made for federal and state income taxes in the accompanying consolidated financial statements. If any subsidiary REIT fails to qualify as a REIT in any taxable year, that subsidiary REIT will be subject to federal and state income taxes and may not be able to qualify as a REIT for the four subsequent taxable years. Also, each subsidiary REIT may be subject to certain local income taxes.

The Operating Partnership has elected to treat several of its subsidiaries as taxable TRSs, which are subject to federal, state and local income tax.

Recent Accounting Pronouncement [Policy Text Block]

Recent Accounting Pronouncements

In February 2013, the Financial Accounting Standards Board (FASB) issued an amendment to the accounting standard for the presentation of comprehensive income. This amendment requires an entity to provide information about the amounts reclassified out of accumulated other comprehensive income by component, and represents the culmination of the FASB's redeliberation on the reporting of such reclassification adjustments. In addition, an entity is required to present, either on the face of the statement where net income is presented or in the notes, significant amounts reclassified out of accumulated other comprehensive income by the respective line items of net income, but only if the amount reclassified is required under U.S. GAAP to be reclassified to net income in its entirety in the same reporting period. For other amounts that are not required under U.S. GAAP to be reclassified in their entirety to net income, an entity is required to cross-reference to other disclosures required under U.S. GAAP that provide additional detail about those amounts. This update is effective for fiscal years and interim periods beginning after December 15, 2012. The Company’s adoption of the accounting standard did not have a material impact on its consolidated financial position or results of operations as the update relates only to changes in financial statement presentation.

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Deferred Costs Deferred Costs (Tables)

9 Months Ended

Sep. 30, 2013

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Components Of Deferred Costs Net [Table Text Block]

As of September 30, 2013 and December 31, 2012, the Company’s deferred costs were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	159,113	$	(59,569	)	$	99,544
Financing Costs	40,116		(13,400		)	26,716
Total	$	199,229	$	(72,969	)	$	126,260

	December 31, 2012
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	150,331	$	(58,343	)	$	91,988
Financing Costs	40,246		(9,991		)	30,255
Total	$	190,577	$	(68,334	)	$	122,243

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Share Based and Deferred Compensation Share Based and Deferred Compensation (Restricted Share Activity) (Details) (Restricted Stock [Member], USD $)	9 Months Ended
	Sep. 30, 2013
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested at January 1, 2013, shares	597,708
Non-vested at January 1, 2013, Weighted Average Grant Date Fair Value	$ 9.46
Granted, Shares	182,576
Granted, Weighted Average Grant Date Fair Value	$ 13.13
Vested, shares	(208,306)
Vested, Weighted Average Grant Date Fair Value	$ 13.13
Forfeited, shares	(8,265)
Forfeited, Weighted Average Grant Date Fair Value	$ 11.41
Non-vested at June 30, 2013, shares	563,713
Non-vested at June 30, 2013, Weighted Average Grant Date Fair Value	$ 12.56

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Discontinued Operations Discontinued Operations (Tables)

9 Months Ended

Sep. 30, 2013

Discontinued Operations and Disposal Groups [Abstract]

Disclosure of Long Lived Assets Held-for-sale [Table Text Block]

The following table summarizes balance sheet information for one property designated as held-for-sale as of September 30, 2013 (in thousands);

	September 30,
	2013
Real Estate Investments:
Operating properties	$	3,724
Accumulated depreciation	(1,399		)
	2,325
Construction-in-progress	—
	2,325
Other assets	46
Total assets held for sale	$	2,371

Long Lived Assets Held-for-sale [Line Items]

Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Table Text Block]

For the three and nine-month periods ended September 30, 2013, income from discontinued operations relates to the twelve properties sold by the Company during 2013, as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The Company determined the property met the criteria for assets held-for-sale pursuant to the related requirements provided for the classification as held for sale under the accounting standard for long lived assets. Accordingly, at September 30, 2013, the property is required to be measured at the lower of its carrying value or the estimated fair value less costs to sell. No provision for impairment was recognized at September 30, 2013 as the estimated fair value of the property less costs to sell are higher than the carrying value based on a purchase and sale agreement. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2013 (in thousands):

	Three-month period ended September 30, 2013			Nine-month period ended  September 30, 2013
Revenue:
Rents	$	—		$	4,129
Tenant reimbursements	3			334
Other	—			123
Total revenue	3			4,586
Expenses:
Property operating expenses	38			1,672
Real estate taxes	17			557
Depreciation and amortization	18			1,769
Total operating expenses	73			3,998
Other income:
Interest income	—			2
Income (Loss) from discontinued operations before gain on sale of interests in real estate	(70		)	590
Net gain (loss) on disposition of discontinued operations	(16		)	3,029
Income (Loss) from discontinued operations	$	(86	)	$	3,619

For the three and nine-month periods ended September 30, 2012, income from discontinued operations relates to the 26 properties sold by the Company from January 1, 2012 through September 30, 2013 as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2012 (in thousands):

	Three-month period ended September 30, 2012		Nine-month period ended  September 30, 2012
Revenue:
Rents	$	5,602	$	22,282
Tenant reimbursements	386		1,872
Termination fees	4		11
Other	129		318
Total revenue	6,121		24,483
Expenses:
Property operating expenses	1,977		6,863
Real estate taxes	707		2,717
Depreciation and amortization	1,788		8,106
Total operating expenses	4,472		17,686
Other income:
Interest income	—		6
Income from discontinued operations before gain on sale of interests in real estate	1,649		6,803
Net gain on disposition of discontinued operations	9,940		34,774
Income from discontinued operations	$	11,589	$	41,577

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Share Based and Deferred Compensation Share Based and Deferred Compensation (Option Activity) (Details) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term	5 years 4 months 29 days	7 years 2 months 13 days
Share Based Compensation Arrangement By Share Based Payment Award Option Activity [Abstract]
Outstanding at the beginning of year, shares	3,337,549
Outstanding at beginning of year, Weighted Average Exercise Price	$ 14.50
Outstanding at beginning of year, Aggregate Intrinsic Value	$ 0
Granted, shares	0
Granted, Weighted Average Grant Date Fair Value	$ 0.00
Exercised in Period, Shares	(207,941)
Exercises in Period, Weighted Average Grant Date Fair Value	$ 10.52
Forfeited, shares	(117,662)
Forfeited, Weighted Average Grant Date Fair Value	$ 18.61
Outstanding at the end of year, shares	3,011,946.000	3,337,549
Outstanding at end of year, Weighted Average Exercise Price	$ 15.40	$ 14.50
Outstanding at end of year, Aggregate Intrinsic Value	0	0
Vested/Exerciseable, shares	2,827,517
Vested/Exerciseable at end of period, Weigted Average Exercise Price	$ 15.63
Vested/Exerciseable at end of period, Weighted Average Remaining Contractual Term (in years)	5 years 3 months 20 days
Vested/Exercisable at end of year, Aggregate Intrinsic Value	$ 0
Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award Option Activity [Abstract]
Vested/Exerciseable, shares	2,827,517

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Debt Obligations Debt Obligations (Consolidated Debt Obligations Outstanding) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Net unamortized premiums/(discounts)	$ (5,452)
Total mortgage indebtedness	434,895	442,974
Total Debt Obligations	2,377,191	2,465,330
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	435,590	443,942
Net unamortized premiums/(discounts)	(695)	(968)
Total mortgage indebtedness	434,895	442,974
Unsecured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	1,947,053	2,027,953
Net unamortized premiums/(discounts)	(4,757)	(5,597)
Total unsecured indebtedness	1,942,296	2,022,356
Unsecured Debt [Member] | Credit Facility
Debt Instrument [Line Items]
Long-term Debt, Gross	0	69,000
Debt Instrument Interest Rates Effective Percentage	LIBOR + 1.50%
Debt Instrument Maturity Dates	Feb-16
Unsecured Debt [Member] | Three Year Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	150,000	150,000
Debt Instrument, Interest Rate, Effective Percentage	2.60%
Debt Instrument Maturity Dates	Feb-15
Unsecured Debt [Member] | Four-Year Term Loan - Variable [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	100,000	100,000
Debt Instrument Interest Rates Effective Percentage	LIBOR + 1.75%
Debt Instrument Maturity Dates	Feb-16
Unsecured Debt [Member] | Seven Year Term Loan [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	200,000	200,000
Debt Instrument, Interest Rate, Effective Percentage	3.62%
Debt Instrument Maturity Dates	Feb-19
Unsecured Debt [Member] | 2014 5.400% Notes
Debt Instrument [Line Items]
Long-term Debt, Gross	232,199	238,379
Debt Instrument, Interest Rate, Effective Percentage	5.53%
Debt Instrument Maturity Dates	Nov-14
Unsecured Debt [Member] | $250.0M 7.500% Guaranteed Notes due 2015
Debt Instrument [Line Items]
Long-term Debt, Gross	161,325	166,535
Debt Instrument, Interest Rate, Effective Percentage	7.76%
Debt Instrument Maturity Dates	May-15
Unsecured Debt [Member] | $250.0M 6.000% Guranteed Notes due 2016 [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	149,919	150,429
Debt Instrument, Interest Rate, Effective Percentage	5.95%
Debt Instrument Maturity Dates	Apr-16
Unsecured Debt [Member] | $300.0M 5.700% Guaranteed Notes due 2017
Debt Instrument [Line Items]
Long-term Debt, Gross	300,000	300,000
Debt Instrument, Interest Rate, Effective Percentage	5.68%
Debt Instrument Maturity Dates	May-17
Unsecured Debt [Member] | $325.0M 4.950% Guaranteed Notes due 2018
Debt Instrument [Line Items]
Long-term Debt, Gross	325,000	325,000
Debt Instrument, Interest Rate, Effective Percentage	5.13%
Debt Instrument Maturity Dates	Apr-18
Unsecured Debt [Member] | $250.0M 3.950% Guaranteed Notes due 2023
Debt Instrument [Line Items]
Long-term Debt, Gross	250,000	250,000
Debt Instrument, Interest Rate, Effective Percentage	4.02%
Debt Instrument Maturity Dates	Feb-23
Unsecured Debt [Member] | Indenture IA (Preferred Trust I) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	27,062	27,062
Debt Instrument, Interest Rate, Effective Percentage	2.75%
Debt Instrument Maturity Dates	Mar-35
Unsecured Debt [Member] | Indenture IB (Preferred Trust I) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	25,774	25,774
Debt Instrument, Interest Rate, Effective Percentage	3.30%
Debt Instrument Maturity Dates	Apr-35
Unsecured Debt [Member] | Indenture II (Preferred Trust II) [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	25,774	25,774
Debt Instrument, Interest Rate, Effective Percentage	3.09%
Debt Instrument Maturity Dates	Jul-35
Tysons Corner [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	91,855	93,188
Debt Instrument, Interest Rate, Effective Percentage	5.36%
Debt Instrument Maturity Dates	Aug-15
Two Logan Square [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	88,782	89,340
Debt Instrument, Interest Rate, Effective Percentage	7.57%
Debt Instrument Maturity Dates	Apr-16
Fairview Eleven Tower [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	21,754	22,000
Debt Instrument, Interest Rate, Effective Percentage	4.25%
Debt Instrument Maturity Dates	Jan-17
IRS Philadelphia Campus [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	192,535	197,111
Debt Instrument, Interest Rate, Effective Percentage	7.00%
Debt Instrument Maturity Dates	Sep-30
Cira South Garage [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 40,664	$ 42,303
Debt Instrument, Interest Rate, Effective Percentage	7.12%
Debt Instrument Maturity Dates	Sep-30

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Investment in Unconsolidated Ventures Investment in Unconsolidated Ventures (Financial Position of Unconsolidated Real Estate Ventures) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Company's share of equity (Company's Basis)	$ 194,572	$ 193,555
Unconsolidated Real Estate Ventures [Member]
Schedule of Equity Method Investments [Line Items]
Net property	879,838	923,536
Other assets	164,508	174,677
Other liabilities	36,115	53,645
Debt	707,847	724,780
Equity	300,384	319,788
Company's share of equity (Company's Basis)	$ 194,572	$ 193,555

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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Fair Value Measurements) (Details) (Fair Value, Measurements, Recurring [Member], Interest Rate Swap [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	$ 112	$ 0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	4,314	14,210
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	0	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0	0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	112
Financial and Nonfinancial Liabilities, Fair Value Disclosure	4,314	14,210
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	0	0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0

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Consolidated Balance Sheets Consolidated Balance Sheets (Parentheticals) (USD $)	9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 BRANDYWINE OPERATING PARTNERSHIP, L.P.	Dec. 31, 2012 BRANDYWINE OPERATING PARTNERSHIP, L.P.
Preferred Stock, Shares Authorized	20,000,000	20,000,000
Preferred Stock, Dividend Rate, Percentage	6.90%	6.90%	6.90%	6.90%
Preferred Stock, Shares Issued	4,000,000	4,000,000	4,000,000	4,000,000
Preferred Stock, Shares Outstanding	4,000,000	4,000,000	4,000,000	4,000,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	200,000,000	200,000,000
Common Stock, Shares, Issued	156,703,790	143,538,733
Common Stock, Shares, Outstanding	156,703,790	143,538,733
Common shares in grantor trust	313,023	290,745
Redeemable Limited Partnership Units Issued			1,763,739	1,845,737
Redeemable Limited Partnership Units Outstanding			1,763,739	1,845,737
General Partners' Capital Account, Units Issued			156,703,790	143,538,733
General Partners' Capital Account, Units Outstanding			156,703,790	143,538,733

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Deferred Costs

9 Months Ended

Sep. 30, 2013

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]

Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]

DEFERRED COSTS

As of September 30, 2013 and December 31, 2012, the Company’s deferred costs were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	159,113	$	(59,569	)	$	99,544
Financing Costs	40,116		(13,400		)	26,716
Total	$	199,229	$	(72,969	)	$	126,260

	December 31, 2012
	Total Cost		Accumulated Amortization			Deferred Costs, net
Leasing Costs	$	150,331	$	(58,343	)	$	91,988
Financing Costs	40,246		(9,991		)	30,255
Total	$	190,577	$	(68,334	)	$	122,243

During the three and nine-month periods ended September 30, 2013, the Company capitalized internal direct leasing costs of $1.4 million and $4.3 million, respectively, and $1.3 million and $4.0 million during the three and nine-month periods ended September 30, 2012, respectively, in accordance with the accounting standard for the capitalization of leasing costs.

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Consolidated Statements of Comprehensive Income Statement (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income	$ 11,088	$ 17,089	$ 22,187	$ 33,227
Comprehensive Income (Loss)
Unrealized gain (loss) on derivative financial instruments	(1,302)	(4,222)	9,978	(14,780)
Reclassification of realized (gains)/losses on derivative financial instruments to operations, net	64	76	232	200
Unrealized gain on available-for-sale securities	0	65	0	0
Total comprehensive income (loss)	(1,238)	(4,081)	10,210	(14,580)
Comprehensive Income	9,850	13,008	32,397	18,647
Comprehensive (income) attributable to non-controlling interest	(91)	(186)	(312)	(158)
Comprehensive income (loss) attributable to Brandywine Realty Trust	9,759	12,822	32,085	18,489
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Net income	11,088	17,089	22,187	33,227
Comprehensive Income (Loss)
Unrealized gain (loss) on derivative financial instruments	(1,302)	(4,222)	9,978	(14,780)
Reclassification of realized (gains)/losses on derivative financial instruments to operations, net	64	76	232	200
Unrealized gain on available-for-sale securities	0	65	0	0
Total comprehensive income (loss)	(1,238)	(4,081)	10,210	(14,580)
Comprehensive Income	$ 9,850	$ 13,008	$ 32,397	$ 18,647

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Debt Obligations Debt Obligations (Details Textuals) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Debt Instrument [Line Items]
Unsecured credit facility	$ 0		$ 69,000,000
Repayments of Unsecured Debt	0	37,500,000
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term Debt, Weighted Average Interest Rate	6.64%	6.72%
Unsecured Debt [Member] | Three Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	150,000,000
Derivative, Average Fixed Interest Rate	2.596%
Unsecured Debt [Member] | Letter of Credit [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount	1,300,000
Unsecured Debt [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	598,700,000
Line of Credit Facility, Option for Additional Borrowing Capacity subject to customary conditions and limitations	200,000,000
Unsecured Debt [Member] | Four Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250,000,000
Unsecured Debt [Member] | Seven Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 200,000,000
Declining prepayment penalty in Year One	3.00%
Declining prepayment penalty in Year Two	2.00%
Declining prepayment penalty after Three Years	1.00%
Derivative, Average Fixed Interest Rate	3.623%

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Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Real estate investments:
Operating properties	$ 4,631,910	$ 4,726,169
Accumulated depreciation	(998,409)	(954,665)
Operating real estate investments, net	3,633,501	3,771,504
Construction-in-progress	52,702	48,950
Land inventory	94,097	102,439
Total real estate investments, net	3,780,300	3,922,893
Cash and cash equivalents	185,517	1,549
Accounts receivable, net	13,718	13,232
Accrued rent receivable, net	128,232	122,066
Assets held for sale, net	2,371	0
Investment in real estate ventures, at equity	194,572	193,555
Deferred costs, net	126,260	122,243
Intangible assets, net	54,457	70,620
Notes receivable	7,026	7,226
Other assets	65,689	53,325
Total assets	4,558,142	4,506,709
LIABILITIES AND BENEFICIARIES’ EQUITY
Mortgage notes payable	434,895	442,974
Unsecured credit facility	0	69,000
Unsecured term loans	450,000	450,000
Unsecured senior notes, net of discounts	1,492,296	1,503,356
Accounts payable and accrued expenses	89,087	71,579
Distributions payable	25,579	23,652
Deferred income, gains and rent	69,637	82,947
Acquired lease intangibles, net	28,500	33,859
Other liabilities	46,990	55,826
Total liabilities	2,636,984	2,733,193
Commitments and contingencies (Note 17)
Equity:
6.90% Series E Preferred Units; issued and outstanding- 4,000,000 in 2013 and 2012	40	40
Common Shares of Brandywine Realty Trust’s beneficial interest, $0.01 par value; shares authorized 200,000,000; 156,703,790 and 143,538,733 issued and outstanding in 2013 and 2012, respectively	1,565	1,434
Additional paid-in capital	2,970,576	2,780,194
Deferred compensation payable in common shares	5,431	5,352
Common shares in grantor trust, 313,023 in 2013 and 290,745 in 2012	(5,431)	(5,352)
Cumulative earnings	501,735	479,734
Accumulated other comprehensive loss	(5,825)	(15,918)
Cumulative distributions	1,567,202	1,493,206
Total equity, excluding non-controlling interest	1,900,889	1,752,278
Non-controlling interests	20,269	21,238
Total equity	1,921,158	1,773,516
Total liabilities and equity	4,558,142	4,506,709
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Real estate investments:
Operating properties	4,631,910	4,726,169
Accumulated depreciation	(998,409)	(954,665)
Operating real estate investments, net	3,633,501	3,771,504
Construction-in-progress	52,702	48,950
Land inventory	94,097	102,439
Total real estate investments, net	3,780,300	3,922,893
Cash and cash equivalents	185,517	1,549
Accounts receivable, net	13,718	13,232
Accrued rent receivable, net	128,232	122,066
Assets held for sale, net	2,371	0
Investment in real estate ventures, at equity	194,572	193,555
Deferred costs, net	126,260	122,243
Intangible assets, net	54,457	70,620
Notes receivable	7,026	7,226
Other assets	65,689	53,325
Total assets	4,558,142	4,506,709
LIABILITIES AND BENEFICIARIES’ EQUITY
Mortgage notes payable	434,895	442,974
Unsecured credit facility	0	69,000
Unsecured term loans	450,000	450,000
Unsecured senior notes, net of discounts	1,492,296	1,503,356
Accounts payable and accrued expenses	89,087	71,579
Distributions payable	25,579	23,652
Deferred income, gains and rent	69,637	82,947
Acquired lease intangibles, net	28,500	33,859
Other liabilities	46,990	55,826
Total liabilities	2,636,984	2,733,193
Commitments and contingencies (Note 17)
Redeemable limited partnership units at redemption value;
Redeemable limited partnership units at redemption value; 1,763,739 and 1,845,737 issued and outstanding in 2013 and 2012, respectively	26,290	26,777
Equity:
6.90% Series E Preferred Units; issued and outstanding- 4,000,000 in 2013 and 2012	96,850	96,850
General Partnership Capital, 156,703,790 and 143,538,733 units issued and outstanding in 2013 and 2012, respectively	1,804,378	1,666,341
Accumulated other comprehensive loss	(6,360)	(16,452)
Total equity, excluding non-controlling interest	1,894,868	1,746,739
Total liabilities and equity	4,558,142	4,506,709
Series E Preferred Stock [Member]
Equity:
Total equity	$ 40	$ 40

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Deferred Costs Deferred Costs (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Components of Deferred Costs Net [Abstract]
Leasing Costs, Total Cost	$ 159,113	$ 150,331
Financing Costs, Total Cost	40,116	40,246
Total Cost	199,229	190,577
Leasing Costs, Accumulated Amortization	(59,569)	(58,343)
Financing Costs, Accumulated Amortization	(13,400)	(9,991)
Total, Accumulated Amortization	72,969	68,334
Leasing, Deferred Costs, Net	99,544	91,988
Financing Costs, Deferred Costs, Net	26,716	30,255
Deferred Costs, Net	$ 126,260	$ 122,243

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Segment Information Segment Information (Reconciliation of Consolidated Net Operating Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Reportable_Segments	Sep. 30, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated net operating income	$ 87,288	$ 80,953	$ 257,865	$ 242,910
Less:
Interest expense	(30,338)	(32,620)	(91,689)	(99,745)
Interest expense — amortization of deferred financing costs	(1,158)	(1,218)	(3,502)	(3,790)
Depreciation and amortization	(50,613)	(46,955)	(149,423)	(142,262)
Interest expense — financing obligation	(264)	(230)	(693)	(608)
General and administrative expenses	(6,436)	(6,080)	(20,322)	(18,209)
Net gain (loss) on sale of undepreciated real estate	(129)	0	(129)	0
Loss On Real Estate Venture Formation	0	950	0	950
Loss on early extinguishment of debt	(11)	(51)	(1,127)	(1,549)
Plus:
Interest income	268	311	448	2,631
Historic tax credit transaction income	11,853	11,840	11,853	11,840
Equity in income of real estate ventures	714	500	3,757	1,382
Gain from remeasurement of investment in a real estate venture	0	0	7,847	0
Net gain on real estate venture transactions	0	0	3,683	0
Income (Loss) from continuing operations	11,174	5,500	18,568	(8,350)
Income (Loss) from Discontinued Operations	(86)	11,589	3,619	41,577
Net income	$ 11,088	$ 17,089	$ 22,187	$ 33,227
Number of Reportable Segments			7

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Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2013

Accounting Policies [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]

The following table sets forth the Company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of September 30, 2013 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	September 30,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2013		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	112	$	—	$	112	$	—
Liabilities:
Interest Rate Swaps	$	4,314	$	—	$	4,314	$	—

The following table sets forth the Company’s financial liabilities that were accounted for at fair value on a recurring basis as of December 31, 2012 (in thousands):

	Fair Value Measurements at Reporting Date Using:
	December 31,		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Unobservable Inputs
Description	2012		(Level 1)		(Level 2)		(Level 3)
Recurring
Assets:
Interest Rate Swaps	$	—	$	—	$	—	$	—
Liabilities:
Interest Rate Swaps	$	14,210	$	—	$	14,210	$	—

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Share Based and Deferred Compensation

9 Months Ended

Sep. 30, 2013

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

SHARE BASED AND DEFERRED COMPENSATION

SHARE BASED AND DEFERRED COMPENSATION

Stock Options

At September 30, 2013, options exercisable for 2,827,517 common shares were outstanding under the Parent Company's shareholder approved equity incentive plan. There were 184,429 options unvested as of September 30, 2013 and $0.2 million of unrecognized compensation expense associated with these options to be recognized over a weighted average term of 0.4 years. During the three and nine-month periods ended September 30, 2013 the Company recognized compensation expense related to unvested options of $0.2 million and $0.6 million, of which a nominal amount and $0.1 million, respectively, were capitalized. During the three and nine-month periods ended September 30, 2012 the Company recognized compensation expense related to unvested options of $0.4 million and $1.1 million, of which $0.1 million and $0.3 million, respectively, were capitalized consistent with the Company’s policies for capitalizing eligible portions of employee compensation.

Option activity as of September 30, 2013 and changes during the nine months ended September 30, 2013 were as follows:

	Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)	Aggregate Intrinsic Value
Outstanding at January 1, 2013	3,337,549		$	14.50	7.2	$	—
Granted	—		—		—	—
Exercised	(207,941	)	$	10.52	—	—
Canceled	(117,662	)	$	18.61
Outstanding at September 30, 2013	3,011,946		$	15.40	5.4	$	—
Vested/Exerciseable at September 30, 2013	2,827,517		$	15.63	5.3	$	—

Restricted Share Awards

As of September 30, 2013, 563,713 restricted shares were outstanding under the 1997 Plan and vest over three to seven years from the initial grant date. At September 30, 2013, approximately $2.4 million of compensation expense remained to be recognized and is expected to be recognized over a weighted average remaining vesting period of 1.4 years. The Company recognized compensation expense related to outstanding restricted shares of $0.9 million and $2.6 million during the three and nine-month periods ended September 30, 2013, of which $0.1 million and $0.4 million, respectively, were capitalized as part of the Company’s policies for capitalizing eligible portions of employee compensation. The Company recognized compensation expense related to outstanding restricted shares of $0.8 million and $2.3 million during the three and nine-month periods ended September 30, 2012, of which $0.2 million and $0.5 million, respectively, were capitalized. The expensed amounts are included in general and administrative expense on the Company’s consolidated statement of operations in the respective periods.

The following table summarizes the Company’s restricted share activity for the nine months ended September 30, 2013:

	Shares		Weighted Average Grant Date Fair value
Non-vested at January 1, 2013	597,708		$	9.46
Granted	182,576		13.13
Vested	(208,306	)	13.13
Forfeited	(8,265	)	11.41
Non-vested at September 30, 2013	563,713		$	12.56

On February 25, 2013, the Compensation Committee of the Parent Company’s Board of Trustees awarded 157,208 restricted shares to the Company’s executives. The restricted shares will cliff vest after three years from the grant date. The vesting of the restricted shares is also subject to acceleration upon a change in control or if the recipient of the award were to die, become disabled or retire in a qualifying retirement. In the case of two of the Company's executives who have employment agreements with the Company, the vesting of the restricted shares is also subject to acceleration if either executive were to be terminated without cause or resign for good reason. Qualifying retirement means the recipient’s voluntary termination of employment after reaching at least age 57 and accumulating at least 15 years of service with the Company. In accordance with the accounting standard for stock-based compensation, the Company amortizes stock-based compensation costs through the qualifying retirement dates for those executives who meet the conditions for qualifying retirement during the scheduled vesting period.

Restricted Performance Share Units Plan

On each of February 25, 2013, March 1, 2012 and March 2, 2011, the Compensation Committee of the Parent Company’s Board of Trustees awarded an aggregate of 231,093, 242,122, and 113,256 share-based awards, respectively, to its executives. These awards are referred to as Restricted Performance Share Units, or RPSUs. The RPSUs represent the right to earn common shares. The number of common shares, if any, deliverable to award recipients depends on the Company’s performance based on its total return to shareholders during the three years measurement period that commenced on January 1, 2013 (in the case of the February 25, 2013 awards), January 1, 2012 (in the case of the March 1, 2012 awards), and January 1, 2011 (in the case of the March 2, 2011 awards), and that ends on December 31, 2015, December 31, 2014 or December 31, 2013 (as applicable) or, if earlier, the date of a change of control. In the case of the awards made on February 25, 2013 and March 1, 2012, the Company's performance is compared to the shareholder return of REITs within an index over the measurement period for 50% of the RPSUs awarded on that date, with the remaining 50% being compared to the total shareholder return of REITs within the Company's proxy peer group over such period. In the case of the awards made on March 2, 2011, the Company's performance is compared to the total shareholder return of REITs within an index over the performance period. The vesting of RPSUs is contingent upon the continued employment of the participants through the performance periods (with exceptions for death, disability and qualifying retirement). Dividends are deemed credited to the performance units accounts and are applied to “acquire” additional RPSUs for the account of the unit holder at the price per common share on the dividend payment date. If earned, RPSUs will be settled in common shares in an amount that reflects both the number of RPSUs in the holder’s account at the end of the applicable measurement period and the Company’s total return to shareholders during the applicable three year measurement period relative to the total shareholder returns of the REITs within the index or peer group, as applicable.

On the date of each grant, the RPSUs were valued using a Monte Carlo simulation. The fair values of the 2013, 2012 and 2011 awards on the grant dates were $4.1 million, $4.2 million and $2.0 million, respectively. The fair values of each award are being amortized over the three year cliff vesting period. The vesting of RPSUs is subject to acceleration upon a change in control or if the recipient of the award were to die, become disabled or retire in a qualifying retirement prior to the vesting date. In the case of two of the Company's executives who have employment agreements with the Company, the vesting of the restricted shares is also subject to acceleration if either executive were to be terminated without cause or resign for good reason. Qualifying retirement means the recipient’s voluntary termination of employment after reaching age 57 and accumulating at least 15 years of service with the Company. In accordance with the accounting standard for stock-based compensation, the Company amortizes stock-based compensation costs through the qualifying retirement date for those executives who meet the conditions for qualifying retirement during the schedule vesting period.

For the three and nine-month periods ended September 30, 2013, the Company recognized total compensation expense for the 2013, 2012 and 2011 RPSU awards of $1.3 million and $3.7 million, of which $0.2 million and $0.6 million, respectively, were capitalized consistent with the Company’s policies for capitalizing eligible portions of employee compensation. For the three and nine-month periods ended September 30, 2012, the Company recognized total compensation expense for the 2012, 2011 and 2010 awards of $0.7 million and $2.1 million, of which $0.2 million and $0.6 million, respectively, were capitalized.

A total of 64,678 common shares vested on December 31, 2012 (the end of the three-year measurement period for the linked RPSUs) and were delivered to holders of the RPSUs on March 1, 2013 in settlement of the RPSUs. Holders of these RPSUs also received cash dividend equivalents to the cash dividends paid on common shares on February 8, 2013.

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Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended	12 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012	Sep. 30, 2013 Purchase money mortgage [Member] Twenty Year Amortization Period [Member]	Dec. 31, 2012 Purchase money mortgage [Member] Twenty Year Amortization Period [Member]	Sep. 30, 2013 Purchase money mortgage [Member] Notes Receivable Due Two Thousand Sixteen [Member]	Dec. 31, 2012 Purchase money mortgage [Member] Notes Receivable Due Two Thousand Sixteen [Member]
Summary of Significant Accounting Policies [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Minimum			1 year
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Term, Maximum			10 years
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES [Abstract]
Revenue Increased By Straight Line Rent Adjustment	$ 4,500,000	$ 4,300,000	$ 14,500,000	$ 16,000,000
Increase In Revenue Due To Amortization Of Deferred Rent	600,000	600,000	1,800,000	1,800,000
Decrease (Increase) In Revenue Due To Lease Incentives	200,000	100,000	400,000	600,000
Guarantor Obligations, Current Carrying Value	600,000		600,000
Increase In Shares Due To Amendments In Plan Shares Solely Available For Options And Share Appreciation Rights	3,011,946		3,011,946
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,195,177		5,195,177
Options Awarded Term			one to ten-year
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount	300,000	500,000	1,100,000	1,400,000
Allocated Share-based Compensation Expense	2,300,000	1,800,000	7,000,000	5,500,000
Notes receivable	7,026,000		7,026,000		7,226,000	7,000,000	7,200,000
Notes Receivable Amortization Period, Years						20 years	20 years	7 years	7 years
Interest income	$ 268,000	$ 311,000	$ 448,000	$ 2,631,000
Mortgage Loans on Real Estate, Interest Rate						8.50%

XML

Commitments and Contingencies Commitments and Contingencies (Ground Rent) (Details) (Ground Rent [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2013
Ground Rent [Member]
Long-term Purchase Commitment [Line Items]
2013 (three months remaining)	$ 549
2014	2,288
2015	2,288
2016	2,288
2017	2,288
Thereafter	280,519
Operating Leases, Future Minimum Payments Due	$ 290,220

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Intangible Assets Annual Amortization of Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Annual amortization of intangible assets and liabilities
Intangible Assets, net	$ 54,457	$ 70,620
Assets [Member]
Annual amortization of intangible assets and liabilities
2013	3,787
2014	13,335
2015	10,661
2016	6,285
2017	5,117
Thereafter	15,272
Intangible Assets, net	54,457
Liabilities [Member]
Annual amortization of intangible assets and liabilities
2013	1,915
2014	6,179
2015	4,014
2016	2,074
2017	1,545
Thereafter	12,773
Intangible Assets, net	$ 28,500

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Non Controlling Interests In the Parent Company Non Controlling Interests In the Parent Company (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Noncontrolling Interest [Abstract]
Aggregate amount related to non-controlling interests classified within equity	$ 20.3	$ 21.2
Settlement Value Of Non Controlling Interest In Operating Partnership	$ 23.2	$ 22.5

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Partners Equity of the Operating Partnership Partners Equity of the Operating Partnership (Tables)

9 Months Ended

Sep. 30, 2013

Equity [Abstract]

Earnings Per Common Partnership Unit [Table Text Block]

Earnings per Common Partnership Unit

The following tables detail the number of units and net income used to calculate basic and diluted earnings per common partnership unit (in thousands, except unit and per unit amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Amount allocable to unvested restricted unitholders	(85		)	(85		)	(95		)	(95		)
Preferred unit dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common unitholders	9,364			9,364			2,620			2,620
Discontinued operations attributable to common unitholders	(86		)	(86		)	11,589			11,589
Net income attributable to common unitholders	$	9,278		$	9,278		$	14,209		$	14,209
Denominator
Weighted-average units outstanding	158,467,087			158,467,087			146,082,206			146,082,206
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average units outstanding	158,467,087			159,755,821			146,082,206			146,785,731
Earnings per Common Partnership Unit:
Income from continuing operations attributable to common unitholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common unitholders	—			—			0.08			0.08
Net income attributable to common unitholders	$	0.06		$	0.06		$	0.10		$	0.10

	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Amount allocable to unvested restricted unitholders	(278		)	(278		)	(286		)	(286		)
Preferred unit dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred unit redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common unitholders	13,115			13,115			(18,558		)	(18,558		)
Discontinued operations attributable to common unitholders	3,619			3,619			41,577			41,577
Net income attributable to common unitholders	$	16,734		$	16,734		$	23,019		$	23,019
Denominator
Weighted-average units outstanding	153,731,070			153,731,070			145,842,872			145,842,872
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average units outstanding	153,731,070			154,940,454			145,842,872			145,842,872
Earnings per Common Partnership Unit:
Income (Loss) from continuing operations attributable to common unitholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common unitholders	0.02			0.02			0.29			0.29
Net income attributable to common unitholders	$	0.11		$	0.11		$	0.16		$	0.16

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Fair Value of Financial Instruments Fair Value of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2013

Fair Value Disclosures [Abstract]

Schedule Of Financial Instruments With Fair Values Different From Their Carrying Amount [Table Text Block]

The following are financial instruments for which the Company’s estimates of fair value differ from the carrying amounts (in thousands):

	September 30, 2013				December 31, 2012
	Carrying Amount		Fair Value		Carrying Amount		Fair Value
Mortgage notes payable	$	435,590	$	473,614	$	443,942	$	486,412
Unsecured notes payable	$	1,418,443	$	1,499,166	$	1,430,343	$	1,553,123
Variable rate debt	$	528,610	$	526,693	$	597,610	$	595,693
Notes receivable	$	7,026	$	7,491	$	7,226	$	7,783

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Risk Management and Use of Financial Instruments Risk Management and Use of Financial Instruments (Tables)

9 Months Ended

Sep. 30, 2013

Derivatives, Fair Value [Line Items]

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]

Hedge Product	Hedge Type	Designation		Notional Amount				Strike		Trade Date	Maturity Date	Fair value
				09/30/2013		12/31/2012						09/30/2013			12/31/2012
Assets:
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.300	%	December 22, 2011	January 30, 2021	112			(1,262		)
				$	25,774	$	25,774					$	112		$	(1,262	)
Liabilities:
Swap	Interest Rate	Cash Flow	(a)	$	200,000	$	200,000	3.623	%	December 6-13, 2011	February 1, 2019	$	(2,369	)	$	(8,859	)
Swap	Interest Rate	Cash Flow	(a)	77,000		77,000		2.703	%	December 9-13, 2011	February 1, 2016	(942		)	(1,343		)
Swap	Interest Rate	Cash Flow	(a)	50,000		50,000		2.470	%	December 13, 2011	February 1, 2015	(327		)	(458		)
Swap	Interest Rate	Cash Flow	(a)	23,000		23,000		2.513	%	December 7-12, 2011	May 1, 2015	(181		)	(245		)
Swap	Interest Rate	Cash Flow	(a)	27,062		27,062		2.750	%	December 21, 2011	September 30, 2017	(410		)	(914		)
Swap	Interest Rate	Cash Flow	(a)	25,774		25,774		3.090	%	January 6, 2012	October 30, 2019	(85		)	(1,129		)
				$	402,836	$	402,836					$	(4,314	)	$	(12,948	)

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Investment in Unconsolidated Ventures

9 Months Ended

Sep. 30, 2013

Equity Method Investments and Joint Ventures [Abstract]

Equity Method Investments and Joint Ventures Disclosure [Text Block]

INVESTMENT IN UNCONSOLIDATED VENTURES

As of September 30, 2013, the Company had an aggregate investment of approximately $194.6 million in 18 unconsolidated Real Estate Ventures. The Company formed or acquired interests in these ventures with unaffiliated third parties to develop or manage office properties or to acquire land in anticipation of possible development of office or residential properties. As of September 30, 2013, 12 of the Real Estate Ventures owned 50 office buildings that contain an aggregate of approximately 6.2 million net rentable square feet; four Real Estate Ventures owned 25.3 acres of undeveloped parcels of land; one Real Estate Venture owned 1.0-acres of land under active development and one Real Estate Venture developed a hotel property that contains 137 rooms in Conshohocken, PA.

The Company accounts for its unconsolidated interests in its Real Estate Ventures using the equity method. The Company’s unconsolidated interests range from 20% to 65%, subject to specified priority allocations of distributable cash in certain of the Real Estate Ventures.

The amounts reflected in the following tables (except for the Company’s share of equity and income) are based on the historical financial information of the individual Real Estate Ventures. The Company does not record operating losses of the Real Estate Ventures in excess of its investment balance unless the Company is liable for the obligations of the Real Estate Venture or is otherwise committed to provide financial support to the Real Estate Venture.

The following is a summary of the financial position of the Real Estate Ventures as of September 30, 2013 and December 31, 2012 (in thousands):

	September 30, 2013		December 31, 2012
Net property	$	879,838	$	923,536
Other assets	164,508		174,677
Other liabilities	36,115		53,645
Debt	707,847		724,780
Equity	300,384		319,788
Company’s share of equity (Company’s basis) (a)	194,572		193,555

(a) Amounts reflect the effects of basis differences resulting from assets contributed to Real Estate Ventures, as well as certain costs at the Real Estate Venture level. Basis differences occur from the impairment of investments and upon the transfer of assets that were previously owned by the Company into a Real Estate Venture. In addition, certain acquisition, transaction and other costs may not be reflected in the net assets at the Real Estate Venture level.

The following is a summary of results of operations of the Real Estate Ventures for the three and nine-month periods ended September 30, 2013 and 2012 (in thousands):

	Three-month periods ended September 30,					Nine-month periods ended September 30,
	2013			2012		2013			2012
Revenue	$	30,684		$	42,772	$	108,500		$	120,644
Operating expenses	13,199			18,753		48,671			51,819
Interest expense, net	9,223			10,233		28,167			31,100
Depreciation and amortization	9,893			12,947		33,778			36,067
Net income (loss)	(1,631		)	839		(2,116		)	1,658
Company’s share of income (Company’s basis)	714			500		3,757			1,382

4040 Wilson Venture

On July 31, 2013, the Company formed 4040 Wilson LLC Venture ("4040 Wilson"), a joint venture between the Company and Ashton Park Associates LLC (“Ashton Park”), an unaffiliated third party. 4040 Wilson expects to construct a 20-story office building located in the Ballston submarket of Arlington, Virginia. Each of the Company and Ashton Park owns a 50% interest in 4040 Wilson. 4040 Wilson would develop the project on a 1.3-acre land parcel contributed by Ashton Park at an agreed upon value of $36.0 million. The total estimated project costs are $194.3 million, which the Company expects would be financed through approximately $72.0 million of partner capital contributions (consisting of $36.0 million in cash from the Company and land with a value of $36.0 million from Ashton Park) and approximately $122.3 million of debt financing through a construction lender that has not yet been determined. Construction is scheduled to commence during the fourth quarter of 2013, with a targeted project completion in 2015. As part of the 4040 Wilson venture, the Company has agreed to guarantee 100% of any lender mandated recourse. As of September 30, 2013, the Company had not provided any guarantees in respect of 4040 Wilson.

Based upon the facts and circumstances at formation of 4040 Wilson, the Company determined that 4040 Wilson is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate 4040 Wilson. Based upon each member's shared power over the activities of 4040 Wilson under the operating and related agreements of 4040 Wilson, and the Company's lack of control over the development and construction phases of the project, 4040 Wilson is not consolidated by the Company, and is accounted for under the equity method of accounting.

Two and Six Tower Bridge Exchange Transaction

On June 19, 2013, the Company acquired, from an unaffiliated third party, the third party's ownership interest in Six Tower Bridge real estate venture through a nonmonetary exchange for the Company's ownership interest in the Two Tower Bridge real estate venture. Six Tower Bridge owns an unencumbered office property in Conshohocken, PA. The Company previously accounted for its noncontrolling interest in Six Tower Bridge using the equity method. As a result of the exchange transaction, the Company obtained control of the Six Tower Bridge property and the Company's existing equity interest was remeasured at fair value based on the fair value of the underlying property and the distribution provisions of the real estate venture agreement. Accordingly, during 2013, the Company recorded a gain of approximately $7.8 million, which is reflected in "Gain from remeasurement of investment in a real estate venture" on the accompanying statements of operations. Following the acquisition, the Class A office property in Conshohocken, PA is wholly owned by the Company with an unencumbered fair value of $24.5 million. The Company accounted for this acquisition as a business combination and allocated the fair value as follows: $14.8 million to building, $6.9 million to land, $3.3 million to intangible assets and $0.5 million to below market lease liabilities assumed.

As mentioned above, the Company exchanged its investment in Two Tower Bridge real estate venture in a nonmonetary transaction with an unaffiliated third party for the third party's interest in the Six Tower Bridge real estate venture. The investment in Two Tower Bridge had a fair value of $3.6 million on the date of the exchange transaction based on the fair value of the venture's equity and the distribution provisions of the real estate venture agreement. Based on this fair value and the carrying value for the Company's investment of $(0.1) million, during 2013 the Company recognized a gain on exchange ofinterests in real estate venturesof $3.7 million.

evo at Cira Centre South Venture (formerly the Grove Venture)

On January 25, 2013, the Company formed the evo at Cira Centre South Venture, a joint venture among the Company and two unaffiliated third parties: Campus Crest Properties, LLC ("Campus Crest") and HSRE-Campus Crest IXA, LLC ("HSRE"). The evo at Cira Centre South Venture has commenced construction of a 33-story, 850-bed student housing tower located in the University City submarket of Philadelphia, Pennsylvania, to be called "evo at Cira Centre South." Each of the Company and Campus Crest owns a 30% interest in the evo at Cira Centre South Venture and HSRE owns a 40% interest. The evo at Cira Centre South Venture is developing the project on a one-acre land parcel held under a long-term ground lease with a third party lessor. The Company contributed to the evo at Cira Centre South Venture its tenancy rights under a long-term ground lease, together with associated development rights, at an agreed-upon value of $8.5 million. The total estimated project costs are $158.5 million, which will be financed through partner capital contributions totaling $60.7 million, with the remaining $97.8 million being financed through construction facilities provided by PNC Bank, Capital One and First Niagara Bank. Construction has already commenced, with a targeted project completion in 2014. In connection with the development of the evo at Cira Centre South Venture, each of the Company and Campus Crest provided, in addition to customary non-recourse carve-out guarantees, a completion and cost overrun guaranty, as well as a payment guaranty, on the construction financing (with the Company's share of the payment guaranty being approximately $23.0 million).

The Company's historical cost basis in the development rights that it contributed to the evo at Cira Centre South Venture at formation was $6.0 million, thus creating an initial $2.5 million basis difference between the Company's initial outside investment basis compared to its $8.5 million initial equity basis in the evo at Cira Centre South Venture. As this basis difference is not related to a physical land parcel, but rather to development rights to construct evo at Cira Centre South, the Company will accrete the basis difference as a reduction of depreciation expense over the life of the evo at Cira Centre South Venture's assets.

Based upon the facts and circumstances at evo at Cira Centre South Venture Venture formation, the Company determined that the evo at Cira Centre South Venture is a VIE in accordance with the accounting standard for the consolidation of VIEs. As a result, the Company used the variable interest model under the accounting standard for consolidation in order to determine whether to consolidate the evo at Cira Centre South Venture. Based upon each member's shared power over the activities of the evo at Cira Centre South Venture under the operating and related agreements of the evo at Cira Centre South Venture, and the Company's lack of exclusive control over the development and construction phases of the project, the evo at Cira Centre South Venture is not consolidated by the Company, and is accounted for under the equity method of accounting. Accordingly, the land parcel and associated development rights contributed by the Company to the evo at Cira Centre South Venture were deconsolidated by the Company upon formation of the evo at Cira Centre South Venture.

BDN Beacon Venture

On March 26, 2013, the Company sold its entire 20% ownership interest in an unconsolidated real estate venture known as BDN Beacon Venture LLC (the "Beacon Venture"). The carrying amount of the Company's investment in the Beacon Venture amounted to $17.0 million at the sale date, with the Company's proceeds effectively matching the carrying amount.

The Company, from time to time, also provides guarantees and indemnities on behalf of Real Estate Ventures, including environmental indemnities and non-recourse carve-outs under mortgage loans, in connection with both construction and permanent financing. As of September 30, 2013, the Company had guaranteed repayment of approximately $0.6 million of loans on behalf of the PJP VII Real Estate Venture.

XML

Risk Management and Use of Financial Instruments Risk Management and Use of Financial Instruments (Fair Values of Derivative Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	$ 25,774	$ 25,774
Derivative, Fair Value, Net	112	(1,262)
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	402,836	402,836
Derivative, Fair Value, Net	(4,314)	(12,948)
3.300% Interest Rate Swap Maturing January 30, 2021 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	25,774	25,774
Derivative, Fixed Interest Rate	3.30%
Derivative, Fair Value, Net	112	(1,262)
3.090% Interest Rate Swap Maturing October 30, 2019 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	25,774	25,774
Derivative, Fixed Interest Rate	3.09%
Derivative, Fair Value, Net	(85)	(1,129)
3.623% Interest Rate Swap Maturing February 1, 2019 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	200,000	200,000
Derivative, Fixed Interest Rate	3.623%
Derivative, Fair Value, Net	(2,369)	(8,859)
2.703% Interest Rate Swap Maturing February 1, 2016 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	77,000	77,000
Derivative, Fixed Interest Rate	2.703%
Derivative, Fair Value, Net	(942)	(1,343)
2.470% Interest Rate Swap Maturing February 1, 2015 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	50,000	50,000
Derivative, Fixed Interest Rate	2.47%
Derivative, Fair Value, Net	(327)	(458)
2.513% Interest Rate Swap Maturing May 1, 2015 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	23,000	23,000
Derivative, Fixed Interest Rate	2.513%
Derivative, Fair Value, Net	(181)	(245)
2.750% Interest Rate Swap Maturing September 30, 2017 [Member] | Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount	27,062	27,062
Derivative, Fixed Interest Rate	2.75%
Derivative, Fair Value, Net	$ (410)	$ (914)

XML

Real Estate Investments Real Estate Investments (Tables)

9 Months Ended

Sep. 30, 2013

Real Estate [Abstract]

Gross Carrying Value Of Company's Properties [Table Text Block]

As of September 30, 2013 and December 31, 2012, the gross carrying value of the Company’s Properties was as follows (in thousands):

	September 30, 2013		December 31, 2012
Land	$	664,952	$	662,107
Building and improvements	3,465,544		3,576,065
Tenant improvements	501,414		487,997
	$	4,631,910	$	4,726,169

XML

Commitments and Contingencies Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2013

Commitments and Contingencies Disclosure [Abstract]

Operating Leases Future Minimum Payments Due [Table Text Block]

Ground Rent

Future minimum rental payments under the terms of all non-cancelable ground leases under which the Company is the lessee are expensed on a straight-line basis regardless of when payments are due. The Company’s ground leases have remaining lease terms ranging from 16 to 90 years. Minimum future rental payments on non-cancelable leases at September 30, 2013 are as follows (in thousands):

2013 (three months remaining)	$	549
2014	2,288
2015	2,288
2016	2,288
2017	2,288
Thereafter	280,519
Total	$	290,220

XML

Debt Obligations

9 Months Ended

Sep. 30, 2013

Debt Disclosure [Abstract]

Debt Disclosure [Text Block]

DEBT OBLIGATIONS

The following table sets forth information regarding the Company’s consolidated debt obligations outstanding at September 30, 2013 and December 31, 2012 (in thousands):

Property / Location	September 30, 2013			December 31, 2012			Effective Interest Rate			Maturity Date
MORTGAGE DEBT:
Tysons Corner	$	91,855		$	93,188		5.36	%	(a)	Aug-15
Two Logan Square	88,782			89,340			7.57	%		Apr-16
Fairview Eleven Tower	21,754			22,000			4.25	%		Jan-17
IRS Philadelphia Campus	192,535			197,111			7.00	%		Sep-30
Cira South Garage	40,664			42,303			7.12	%		Sep-30
Principal balance outstanding	435,590			443,942
Plus: fair market value premiums (discounts), net	(695		)	(968		)
Total mortgage indebtedness	$	434,895		$	442,974
UNSECURED DEBT:
Credit Facility	—			69,000			LIBOR + 1.50%			Feb-16
Three-Year Term Loan - Swapped to fixed	150,000			150,000			2.60	%		Feb-15
Four-Year Term Loan - Variable	100,000			100,000			LIBOR + 1.75%			Feb-16
Seven-Year Term Loan - Swapped to fixed	200,000			200,000			3.62	%		Feb-19
$250.0M 5.400% Guaranteed Notes due 2014	232,199			238,379			5.53	%		Nov-14
$250.0M 7.500% Guaranteed Notes due 2015	161,325			166,535			7.76	%		May-15
$250.0M 6.000% Guaranteed Notes due 2016	149,919			150,429			5.95	%		Apr-16
$300.0M 5.700% Guaranteed Notes due 2017	300,000			300,000			5.68	%		May-17
$325.0M 4.950% Guaranteed Notes due 2018	325,000			325,000			5.13	%		Apr-18
$250.0M 3.950% Guaranteed Notes due 2023	250,000			250,000			4.02	%		Feb-23
Indenture IA (Preferred Trust I)	27,062			27,062			2.75	%		Mar-35
Indenture IB (Preferred Trust I)	25,774			25,774			3.30	%		Apr-35
Indenture II (Preferred Trust II)	25,774			25,774			3.09	%		Jul-35
Principal balance outstanding	1,947,053			2,027,953
Plus: original issue premiums (discounts), net	(4,757		)	(5,597		)
Total unsecured indebtedness	$	1,942,296		$	2,022,356
Total Debt Obligations	$	2,377,191		$	2,465,330

(a) This loan was assumed upon acquisition of the property that secures the mortgage debt. The interest rate reflects the market rate at the time of acquisition.

During the nine-month periods ended September 30, 2013 and September 30, 2012, the Company’s weighted-average effective interest rate on its mortgage notes payable was 6.64% and 6.72%, respectively.

During the nine months ended September 30, 2013, the Company repurchased $11.9 million in principal amount of its outstanding unsecured notes in a series of transactions that are summarized in the following table (in thousands):

Notes	Repurchase Amount		Principal		Loss			Deferred Financing Amortization
2014 5.400% Notes	$	6,570	$	6,180	$	(401	)	$	7
2015 7.500% Notes	5,843		5,210		(663		)	15
2016 6.000% Notes	573		510		(63		)	1
	$	12,986	$	11,900	$	(1,127	)	$	23

The Parent Company unconditionally guarantees the unsecured debt obligations of the Operating Partnership (or is a co-borrower with the Operating Partnership) but does not by itself incur unsecured indebtedness. The Parent Company has no material assets other than its investment in the Operating Partnership.

The Company utilizes its unsecured revolving credit facility (the "Credit Facility") for general business purposes, including to fund costs of acquisitions, developments and redevelopments and repayment of other debt. The scheduled maturity date of the Credit Facility in place at September 30, 2013 is February 1, 2016. The per annum variable interest rate on balances outstanding under the Credit Facility is LIBOR plus 1.50%. The interest rate and facility fee are subject to adjustment upon a change in the Company’s unsecured debt ratings. As of September 30, 2013, the Company did not have any outstanding borrowings on its Credit Facility, with $1.3 million in letters of credit outstanding, leaving $598.7 million of unused availability under the Credit Facility. During each of the three and nine-month periods ended September 30, 2013 and 2012, there were no weighted-average interest rates associated with the Credit Facility because there were no borrowings outstanding under the Credit Facility during either period.

The Company has the option to increase the amounts available to be advanced under the Credit Facility, the $150.0 million three-year term loan, and the $100.0 million four-year term loan by an aggregate of $200.0 million, subject to customary conditions and limitations, by obtaining additional commitments from the current lenders and other financial institutions. The Company also has the option to extend the maturity dates of each of the Credit facility, the $150.0 million three-year term loan and the $100.0 million four-year term loan by one year, subject to payment of an extension fee and other customary conditions and limitations. The Company may repay the $150.0 million three-year term loan and the $100.0 million four-year term loan at any time without penalty. The $200.0 million seven-year term loan is subject to a declining prepayment penalty (3.00% commencing one year after closing, 2.00% after two years, 1.00% after three years and without penalty thereafter).

The spread to LIBOR for LIBOR-based loans under the Credit Facility and term loans depends on the Company's unsecured senior debt credit rating. Based on the Company's current credit rating, the spread for such loans will be 150 basis points under the Credit Facility, 175 basis points under both the $150.0 million three-year term loan and the $100.0 million four-year term loan and 190 basis points under the $200.0 million seven-year term loan. At the Company's option, advances under the Credit Facility and term loans may also bear interest at a per annum floating rate equal to the higher of the prime rate or the federal funds rate plus 0.50% per annum. The Credit Facility contains a competitive bid option that allows banks that are part of the lender consortium to bid to make loans to the Company at a reduced rate. The Company executed hedging transactions that fix the rate on the $200.0 million seven-year term loan at a 3.623% average rate for its full term, and the rate on the $150.0 million three-year term loan at a 2.596% average rate for periods of three to four years. All hedges commenced on February 1, 2012 and the rates are inclusive of the LIBOR spread based on the Company's current investment grade rating. See Note 9 for details of the interest rate swaps entered into as of September 30, 2013.

The Credit Facility and term loans contain financial and operating covenants and restrictions. The Company was in compliance with all such restrictions and financial covenants as of September 30, 2013.

As of September 30, 2013, the Company’s aggregate scheduled principal payments on debt obligations, excluding amortization of discounts and premiums, were as follows (in thousands):

2013 (three months remaining)	$	2,886
2014	244,141
2015	411,358
2016	346,528
2017	330,323
Thereafter	1,047,407
Total principal payments	2,382,643
Net unamortized premiums/(discounts)	(5,452		)
Outstanding indebtedness	$	2,377,191

XML

Segment Information Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Operating properties	$ 4,631,910		$ 4,631,910		$ 4,726,169
Real Estate Investments At Cost [Abstract]
Construction-in-progress	52,702		52,702		48,950
Land inventory	94,097		94,097		102,439
Total revenue	143,456	134,520	424,198	400,113
Property operating expenses	(56,168)	(53,567)	(166,333)	(157,203)
Gross Profit	87,288	80,953	257,865	242,910
Pennsylvania [Member]
Segment Reporting Information [Line Items]
Operating properties	1,196,987		1,196,987		1,178,730
Real Estate Investments At Cost [Abstract]
Total revenue	39,268	38,373	114,730	113,110
Property operating expenses	(13,291)	(13,463)	(40,256)	(39,285)
Gross Profit	25,977	24,910	74,474	73,825
Philadelphia CBD [Member]
Segment Reporting Information [Line Items]
Operating properties	1,026,116		1,026,116		988,590
Real Estate Investments At Cost [Abstract]
Total revenue	35,891	33,026	107,957	98,086
Property operating expenses	(13,704)	(12,432)	(40,826)	(37,080)
Gross Profit	22,187	20,594	67,131	61,006
Metropolitan Dc [Member]
Segment Reporting Information [Line Items]
Operating properties	1,207,243		1,207,243		1,193,200
Real Estate Investments At Cost [Abstract]
Total revenue	29,320	26,516	85,889	79,919
Property operating expenses	(10,321)	(10,638)	(31,856)	(31,156)
Gross Profit	18,999	15,878	54,033	48,763
New Jersey/ Delaware [Member]
Segment Reporting Information [Line Items]
Operating properties	410,143		410,143		546,644
Real Estate Investments At Cost [Abstract]
Total revenue	16,171	15,536	47,449	46,550
Property operating expenses	(8,647)	(7,930)	(23,301)	(22,841)
Gross Profit	7,524	7,606	24,148	23,709
Richmond, Virginia [Member]
Segment Reporting Information [Line Items]
Operating properties	309,646		309,646		309,923
Real Estate Investments At Cost [Abstract]
Total revenue	8,640	8,826	26,359	26,762
Property operating expenses	(3,735)	(3,761)	(11,017)	(10,874)
Gross Profit	4,905	5,065	15,342	15,888
Austin, Texas [Member]
Segment Reporting Information [Line Items]
Operating properties	289,075		289,075		285,346
Real Estate Investments At Cost [Abstract]
Total revenue	9,937	8,274	29,067	23,957
Property operating expenses	(3,958)	(3,485)	(12,123)	(10,494)
Gross Profit	5,979	4,789	16,944	13,463
CALIFORNIA
Segment Reporting Information [Line Items]
Operating properties	192,700		192,700		223,736
Real Estate Investments At Cost [Abstract]
Total revenue	4,632	4,448	13,773	13,034
Property operating expenses	(2,531)	(2,362)	(7,029)	(6,747)
Gross Profit	2,101	2,086	6,744	6,287
Corporate [Member]
Segment Reporting Information [Line Items]
Operating properties	0		0		0
Real Estate Investments At Cost [Abstract]
Construction-in-progress	52,702		52,702		48,950
Land inventory	94,097		94,097		102,439
Total revenue	(403)	(479)	(1,026)	(1,305)
Property operating expenses	19	504	75	1,274
Gross Profit	$ (384)	$ 25	$ (951)	$ (31)

XML

Real Estate Investments

9 Months Ended

Sep. 30, 2013

Real Estate [Abstract]

Real Estate Disclosure [Text Block]

As of September 30, 2013 and December 31, 2012, the gross carrying value of the Company’s Properties was as follows (in thousands):

	September 30, 2013		December 31, 2012
Land	$	664,952	$	662,107
Building and improvements	3,465,544		3,576,065
Tenant improvements	501,414		487,997
	$	4,631,910	$	4,726,169

Acquisitions

On June 19, 2013, the Company acquired the remaining ownership interest in the Real Estate Venture known as "Six Tower Bridge" that it did not then already own. See Note 4 "Investments in Unconsolidated Real Estate Ventures" for further discussion.

On April 25, 2013, the Company exercised its purchase option under the long term ground lease agreement it held through its acquisition of Three Logan Square on August 5, 2010 and acquired the 1.8 acre land parcel underlying Three Logan Square in Philadelphia, Pennsylvania for $20.8 million. The Company has accounted for the transaction as an asset acquisition. A portion of the original purchase price of Three Logan Square was allocated to the below market ground lease intangible asset, as the sum of the purchase price of the land plus the $4.3 million remaining unamortized balance for the intangible asset approximates the fair value of the land as unencumbered by the ground lease. The remaining intangible asset balance was reclassified to land upon exercise of the purchase option. The Company funded the cost of the acquisition with available corporate funds and capitalized $0.1 million of acquisition related costs as part of the basis in the operating land.

Dispositions

On August 5, 2013, the Company sold an eight-acre parcel of land located in Richmond, Virginia known as Dabney Land East, for a sales price of $0.5 million. The land parcel was undeveloped as of the date of sale.

On June 28, 2013, the Company sold 16870 West Bernardo Drive, a 67,909 net rentable square feet office property located in San Diego, California, for a sales price of $18.0 million. The property was 98.8% occupied as of the date of sale.

On June 28, 2013, the Company sold 100 Arrandale Boulevard, a 34,931 net rentable square feet office property located in Exton, Pennsylvania, for a sales price of $3.5 million. The property was vacant at the date of sale.

On June 19, 2013, the Company sold 1700 Paoli Pike, a 28,000 net rentable square feet office property located in Malvern, Pennsylvania, for a sales price of $2.7 million. The property was vacant at the date of sale.

On June 14, 2013, the Company sold Pacific View Plaza, a 51,695 net rentable square feet office property located in Carlsbad, California, for a sales price of $10.3 million. The property was 90.5% occupied as of the date of sale.

On February 25, 2013, the Company sold a portfolio of eight office properties containing 800,546 square feet in Lawrenceville, New Jersey for an aggregate sales price of $121.0 million. These properties, collectively known as "Princeton Pike Corporate Center," were 86.9% occupied as of the date of sale.

The sales of these properties are included in discontinued operations (see Note 10).

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Consolidated Statements of Beneficiaries' Equity Consolidated Statements of Beneficiaries' Equity (Parantheticals) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cumulative Distributions [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.15	$ 0.15
Noncontrolling Interest [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.15	$ 0.15

XML

Deferred Costs Deferred Costs (Details Textuals) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Deferred Costs (Textuals) [Abstract]
Capitalized Internal Direct Leasing Costs	$ 1.4	$ 1.3	$ 4.3	$ 4.0

XML

Real Estate Investments Acquisitions and Dispositions (Details) (USD $)	9 Months Ended										0 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Aug. 05, 2013 Dabney Land, East [Member] acre	Jun. 28, 2013 The Bluffs [Member] sqft	Jun. 19, 2013 1700 Paoli Pike [Member] sqft	Jun. 28, 2013 100 Arrandale Boulevard [Member] sqft	Jun. 14, 2013 Pacific View Plaza [Member] sqft	Feb. 25, 2013 Princeton Pike Corporate Center [Member] sqft Properties	Jul. 31, 2013 4040 Wilson Venture [Member]	Jan. 25, 2013 Brandywine Realty Trust [Member] The Grove at Cira Centre South [Member]	Apr. 25, 2013 Three Logan Square [Member] acre
Significant Acquisitions and Disposals [Line Items]
Construction Loan									$ 122,300,000
Equity Method Investment, Ownership Percentage									50.00%	30.00%
Number of real estate properties sold								8
Net Rentable Space Sold				67,909	28,000	34,931	51,695	800,546
Sale Consideration Of Sold Property			500,000	18,000,000	2,700,000	3,500,000	10,300,000	121,000,000
Lease percentage of sold property				98.80%			90.50%	86.90%
Business Acquisition, Cost of Acquired Entity, Purchase Price											20,800,000
Adjustment to Record Land Acquisition to Fair Value	(4,386,000)	0									4,300,000
Business Acquisition, Cost of Acquired Entity, Transaction Costs											$ 100,000
Land Sold			8
Area of Land											1.8

XML

Intangible Assets Intangible Assets (Tables)

9 Months Ended

Sep. 30, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets [Table Text Block]

As of September 30, 2013 and December 31, 2012, the Company’s intangible assets/liabilities were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	81,410	$	(42,629	)	$	38,781
Tenant relationship value	46,160		(31,786		)	14,374
Above market leases acquired	2,705		(1,403		)	1,302
Total	$	130,275	$	(75,818	)	$	54,457
Below market leases acquired	$	76,874	$	(48,374	)	$	28,500

	December 31, 2012
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	87,909	$	(42,894	)	$	45,015
Tenant relationship value	56,137		(37,389		)	18,748
Above market leases acquired	8,565		(1,708		)	6,857
Total	$	152,611	$	(81,991	)	$	70,620
Below market leases acquired	$	77,083	$	(43,224	)	$	33,859

Annual Amortization For Its Intangible Assets Liabilities [Table Text Block]

As of September 30, 2013, the Company’s annual amortization for its intangible assets/liabilities were as follows (in thousands, and assuming no early lease terminations):

	Assets		Liabilities
2013 (three months remaining)	$	3,787	$	1,915
2014	13,335		6,179
2015	10,661		4,014
2016	6,285		2,074
2017	5,117		1,545
Thereafter	15,272		12,773
Total	$	54,457	$	28,500

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Beneficiaries Equity of the Parent Company Beneficiaries Equity of the Parent Company (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator
Income (Loss) from Continuing Operations, Basic	$ 11,174	$ 5,500	$ 18,568	$ (8,350)
Income (Loss) From Continuing Operations, Diluted	11,174	5,500	18,568	(8,350)
Net Income (Loss) From Continuing Operations Attributable to Non controlling interests, Basic	(106)	(49)	(147)	335
Net Income (Loss) From Continuing Operations Attributable To Non Controlling Interests, Diluted	(106)	(49)	(147)	335
Amount allocated to unvested restricted shareholders/unitholders, Basic	(85)	(95)	(278)	(286)
Amount allocated to unvested restricted shareholders/unitholders, Diluted	(85)	(95)	(278)	(286)
Preferred share/unit dividends, Basic	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share/unit dividends, Diluted	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share redemption charge	0	0	0	(2,090)
Redemption Premium, Diluted			0	(2,090)
Income (Loss) from Continuing Operations Available to Common Shareholders/unitholders, Basic	9,258	2,571	12,968	(18,223)
Income (Loss) from Continuing Operations Available to Common Shareholders/unitholders, Diluted	9,258	2,571	12,968	(18,223)
Income (Loss) from Discontinued Operations	(86)	11,589	3,619	41,577
Income (Loss) From Discontinued Operations, Diluted	(86)	11,589	3,619	41,577
Discontinued operations attributable to non-controlling interests, Basic	1	(211)	(48)	(760)
Discontinued Operations Attributable to Noncontrolling Interests- Diluted	1	(211)	(48)	(760)
Discontinued operations attributable to common shareholders, Basic	(85)	11,378	3,571	40,817
Discontinued operations attributable to common shareholders, Diluted	(85)	11,378	3,571	40,817
Net income attributable to Common Shareholders of Brandywine Realty Trust	9,173	13,949	16,539	22,594
Net Income (Loss) Available to Common Shareholders/unitholders, Diluted	$ 9,173	$ 13,949	$ 16,539	$ 22,594
Denominator
Weighted Average Number of Shares Outstanding, Basic	156,703,348	143,424,485	151,933,441	143,182,911
Contingent securities/Share based compensation	1,288,734	703,525	1,209,384	0
Weighted Average Number of Shares Outstanding, Diluted	157,992,082	144,128,010	153,142,825	143,182,911
Earnings per common share from continuing operations Abstract
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Basic Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Diluted Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued Operations attributable to common shareholders/unitholders, Basic	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Discontinued Operations attributable to common shareholders/unitholders, Diluted	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income (loss) attributable to common shareholders/unitholders, Basic	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Net income attributable to common shareholders/unitholders, Diluted	$ 0.06	$ 0.10	$ 0.11	$ 0.16

XML

Debt Obligations Debt Obligations (Details Textuals 2) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2013
Unsecured Debt [Member] | Four Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 250.0
Debt Instrument, Interest Rate, Stated Percentage	5.40%
Unsecured Debt [Member] | $250.0M 7.500% Guaranteed Notes due 2015
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250.0
Debt Instrument, Interest Rate, Stated Percentage	7.50%
Unsecured Debt [Member] | $250.0M 6.000% Guranteed Notes due 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250.0
Debt Instrument, Interest Rate, Stated Percentage	6.00%
Unsecured Debt [Member] | $300.0M 5.700% Guaranteed Notes due 2017
Debt Instrument [Line Items]
Debt Instrument, Face Amount	300.0
Debt Instrument, Interest Rate, Stated Percentage	5.70%
Unsecured Debt [Member] | $325.0M 4.950% Guaranteed Notes due 2018
Debt Instrument [Line Items]
Debt Instrument, Face Amount	325.0
Debt Instrument, Interest Rate, Stated Percentage	4.95%
Unsecured Debt [Member] | $250.0M 3.950% Guaranteed Notes due 2023
Debt Instrument [Line Items]
Debt Instrument, Face Amount	250.0
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Unsecured Debt [Member] | Three Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	150.0
Debt Instrument Term	3 years
Option to Extend Term Loan	1 year
Debt Instrument, Basis Spread on Variable Rate	1.75%
Unsecured Debt [Member] | Four-Year Term Loan - Variable [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	100.0
Debt Instrument Term	4 years
Option to Extend Term Loan	1 year
Debt Instrument, Basis Spread on Variable Rate	1.75%
Unsecured Debt [Member] | Three and Four Year Term Loan [Member]
Debt Instrument [Line Items]
Derivative, Lower Remaining Maturity Range	3 years
Derivative, Higher Remaining Maturity Range	4 years
Unsecured Debt [Member] | Seven Year Term Loan [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 200.0
Debt Instrument Term	7 years
Debt Instrument, Basis Spread on Variable Rate	1.90%
Senior notes 5.400 Percent due 2014 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.40%
Senior Notes Due2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.50%

XML

Discontinued Operations

9 Months Ended

Sep. 30, 2013

Discontinued Operations and Disposal Groups [Abstract]

DISCONTINUED OPERATIONS [Text Block]

10. DISCONTINUED OPERATIONS

For the three and nine-month periods ended September 30, 2013, income from discontinued operations relates to the twelve properties sold by the Company during 2013, as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The Company determined the property met the criteria for assets held-for-sale pursuant to the related requirements provided for the classification as held for sale under the accounting standard for long lived assets. Accordingly, at September 30, 2013, the property is required to be measured at the lower of its carrying value or the estimated fair value less costs to sell. No provision for impairment was recognized at September 30, 2013 as the estimated fair value of the property less costs to sell are higher than the carrying value based on a purchase and sale agreement. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2013 (in thousands):

	Three-month period ended September 30, 2013			Nine-month period ended  September 30, 2013
Revenue:
Rents	$	—		$	4,129
Tenant reimbursements	3			334
Other	—			123
Total revenue	3			4,586
Expenses:
Property operating expenses	38			1,672
Real estate taxes	17			557
Depreciation and amortization	18			1,769
Total operating expenses	73			3,998
Other income:
Interest income	—			2
Income (Loss) from discontinued operations before gain on sale of interests in real estate	(70		)	590
Net gain (loss) on disposition of discontinued operations	(16		)	3,029
Income (Loss) from discontinued operations	$	(86	)	$	3,619

The following table summarizes balance sheet information for one property designated as held-for-sale as of September 30, 2013 (in thousands);

	September 30,
	2013
Real Estate Investments:
Operating properties	$	3,724
Accumulated depreciation	(1,399		)
	2,325
Construction-in-progress	—
	2,325
Other assets	46
Total assets held for sale	$	2,371

For the three and nine-month periods ended September 30, 2012, income from discontinued operations relates to the 26 properties sold by the Company from January 1, 2012 through September 30, 2013 as well as one property located in West Chester, Pennsylvania designated as held-for-sale as of September 30, 2013. The following table summarizes the revenue and expense information for properties classified as discontinued operations for the three and nine-month periods ended September 30, 2012 (in thousands):

	Three-month period ended September 30, 2012		Nine-month period ended  September 30, 2012
Revenue:
Rents	$	5,602	$	22,282
Tenant reimbursements	386		1,872
Termination fees	4		11
Other	129		318
Total revenue	6,121		24,483
Expenses:
Property operating expenses	1,977		6,863
Real estate taxes	707		2,717
Depreciation and amortization	1,788		8,106
Total operating expenses	4,472		17,686
Other income:
Interest income	—		6
Income from discontinued operations before gain on sale of interests in real estate	1,649		6,803
Net gain on disposition of discontinued operations	9,940		34,774
Income from discontinued operations	$	11,589	$	41,577

Discontinued operations have not been segregated in the consolidated statements of cash flows. Therefore, amounts for certain captions will not agree with respective data in the consolidated statements of operations.

XML

Intangible Assets

9 Months Ended

Sep. 30, 2013

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets Disclosure [Text Block]

INTANGIBLE ASSETS AND LIABILITIES

As of September 30, 2013 and December 31, 2012, the Company’s intangible assets/liabilities were comprised of the following (in thousands):

	September 30, 2013
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	81,410	$	(42,629	)	$	38,781
Tenant relationship value	46,160		(31,786		)	14,374
Above market leases acquired	2,705		(1,403		)	1,302
Total	$	130,275	$	(75,818	)	$	54,457
Below market leases acquired	$	76,874	$	(48,374	)	$	28,500

	December 31, 2012
	Total Cost		Accumulated Amortization			Intangible assets, net
In-place lease value	$	87,909	$	(42,894	)	$	45,015
Tenant relationship value	56,137		(37,389		)	18,748
Above market leases acquired	8,565		(1,708		)	6,857
Total	$	152,611	$	(81,991	)	$	70,620
Below market leases acquired	$	77,083	$	(43,224	)	$	33,859

As of September 30, 2013, the Company’s annual amortization for its intangible assets/liabilities were as follows (in thousands, and assuming no early lease terminations):

	Assets		Liabilities
2013 (three months remaining)	$	3,787	$	1,915
2014	13,335		6,179
2015	10,661		4,014
2016	6,285		2,074
2017	5,117		1,545
Thereafter	15,272		12,773
Total	$	54,457	$	28,500

XML

Partners Equity of the Operating Partnership Partners Equity of the Operating Partnership (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Numerator
Income (Loss) from Continuing Operations, Basic	$ 11,174	$ 5,500	$ 18,568	$ (8,350)
Income (Loss) From Continuing Operations, Diluted	11,174	5,500	18,568	(8,350)
Amount allocated to unvested restricted shareholders/unitholders, Basic	(85)	(95)	(278)	(286)
Amount allocated to unvested restricted shareholders/unitholders, Diluted	(85)	(95)	(278)	(286)
Preferred share/unit dividends, Basic	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share/unit dividends, Diluted	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share redemption charge	0	0	0	(2,090)
Redemption Premium, Diluted			0	(2,090)
Income (Loss) from Discontinued Operations	(86)	11,589	3,619	41,577
Net income attributable to Common Shareholders of Brandywine Realty Trust	9,173	13,949	16,539	22,594
Net Income (Loss) Available to Common Shareholders/unitholders, Diluted	9,173	13,949	16,539	22,594
Denominator
Weighted-average units outstanding, Basic	156,703,348	143,424,485	151,933,441	143,182,911
Contingent securities/Share based compensation	1,288,734	703,525	1,209,384	0
Weighted Average Number of Shares Outstanding, Diluted	157,992,082	144,128,010	153,142,825	143,182,911
Earnings per Common Partnership Unit [Abstract]
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Basic Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Diluted Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued Operations attributable to common shareholders/unitholders, Basic	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Discontinued Operations attributable to common shareholders/unitholders, Diluted	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income (loss) attributable to common shareholders/unitholders, Basic	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Net income attributable to common shareholders/unitholders, Diluted	$ 0.06	$ 0.10	$ 0.11	$ 0.16
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Numerator
Income (Loss) from Continuing Operations, Basic	11,174	5,500	18,568	(8,350)
Income (Loss) From Continuing Operations, Diluted	11,174	5,500	18,568	(8,350)
Amount allocated to unvested restricted shareholders/unitholders, Basic	(85)	(95)	(278)	(286)
Amount allocated to unvested restricted shareholders/unitholders, Diluted	(85)	(95)	(278)	(286)
Preferred share/unit dividends, Basic	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share/unit dividends, Diluted	(1,725)	(2,785)	(5,175)	(7,832)
Preferred share redemption charge	0	0	0	(2,090)
Redemption Premium, Diluted			0	(2,090)
Income (Loss) from continuing operations available to common unitholders, Basic	9,364	2,620	13,115	(18,558)
Income (Loss) from continuing operations available to common unitholders, Diluted	9,364	2,620	13,115	(18,558)
Income (Loss) from Discontinued Operations	(86)	11,589	3,619	41,577
Income (Loss) From Discontinued Operations, Diluted	(86)	11,589	3,619	41,577
Net income attributable to Common Shareholders of Brandywine Realty Trust	9,278	14,209	16,734	23,019
Net Income (Loss) Available to Common Shareholders/unitholders, Diluted	$ 9,278	$ 14,209	$ 16,734	$ 23,019
Denominator
Weighted-average units outstanding, Basic	158,467,087	146,082,206	153,731,070	145,842,872
Contingent securities/Share based compensation	1,288,734	703,525	1,209,384	0
Weighted Average Number of Shares Outstanding, Diluted	159,755,821	146,785,731	154,940,454	145,842,872
Earnings per Common Partnership Unit [Abstract]
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Basic Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Income (Loss) from Continuing Operations Attributable to Common Shareholders/unitholders, Per Diluted Share	$ 0.06	$ 0.02	$ 0.09	$ (0.13)
Discontinued Operations attributable to common shareholders/unitholders, Basic	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Discontinued Operations attributable to common shareholders/unitholders, Diluted	$ 0.00	$ 0.08	$ 0.02	$ 0.29
Net income (loss) attributable to common shareholders/unitholders, Basic	$ 0.06	$ 0.10	$ 0.11	$ 0.16
Net income attributable to common shareholders/unitholders, Diluted	$ 0.06	$ 0.10	$ 0.11	$ 0.16

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Partners Equity of the Operating Partnership

9 Months Ended

Sep. 30, 2013

Equity [Abstract]

Partners Equity of Operating Partnership [Text Block]

PARTNERS’ EQUITY OF THE OPERATING PARTNERSHIP

Earnings per Common Partnership Unit

The following tables detail the number of units and net income used to calculate basic and diluted earnings per common partnership unit (in thousands, except unit and per unit amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Amount allocable to unvested restricted unitholders	(85		)	(85		)	(95		)	(95		)
Preferred unit dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common unitholders	9,364			9,364			2,620			2,620
Discontinued operations attributable to common unitholders	(86		)	(86		)	11,589			11,589
Net income attributable to common unitholders	$	9,278		$	9,278		$	14,209		$	14,209
Denominator
Weighted-average units outstanding	158,467,087			158,467,087			146,082,206			146,082,206
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average units outstanding	158,467,087			159,755,821			146,082,206			146,785,731
Earnings per Common Partnership Unit:
Income from continuing operations attributable to common unitholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common unitholders	—			—			0.08			0.08
Net income attributable to common unitholders	$	0.06		$	0.06		$	0.10		$	0.10

	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Amount allocable to unvested restricted unitholders	(278		)	(278		)	(286		)	(286		)
Preferred unit dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred unit redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common unitholders	13,115			13,115			(18,558		)	(18,558		)
Discontinued operations attributable to common unitholders	3,619			3,619			41,577			41,577
Net income attributable to common unitholders	$	16,734		$	16,734		$	23,019		$	23,019
Denominator
Weighted-average units outstanding	153,731,070			153,731,070			145,842,872			145,842,872
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average units outstanding	153,731,070			154,940,454			145,842,872			145,842,872
Earnings per Common Partnership Unit:
Income (Loss) from continuing operations attributable to common unitholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common unitholders	0.02			0.02			0.29			0.29
Net income attributable to common unitholders	$	0.11		$	0.11		$	0.16		$	0.16

Unvested restricted units are considered participating securities which require the use of the two-class method for the computation of basic and diluted earnings per share. For the nine months ended September 30, 2013 and 2012, earnings representing nonforfeitable dividends as noted in the table above were allocated to the unvested restricted units.

Common Partnership Units and Preferred Mirror Units

On September 10, 2013, the Operating Partnership declared a distribution of $0.15 per common partnership unit, totaling $23.8 million, which was paid on October 18, 2013 to unitholders of record as of October 4, 2013.

On September 10, 2013, the Operating Partnership declared distributions on its Series E-Linked Preferred Mirror Units to holders of record as of September 30, 2013. These units are entitled to a preferential return of 6.90% per annum on the $25.00 per unit liquidation preference. Distributions paid on October 15, 2013 to holders of Series E-Linked Preferred Mirror Units totaled $1.7 million.

On April 10, 2013, the Parent Company closed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership continues to use the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

From January 1, 2013 through expiration of the Offering Program on March 10, 2013, the Parent Company did not sell any shares under the Offering Program and, accordingly, the Operating Partnership did not issue any common partnership units to the Parent Company in connection with the Offering Program during this time. From the inception of the Offering Program in March 2010 through expiration of the Offering Program in March 2013, the Parent Company sold an aggregate of 6,421,553 common shares under the Offering Program at an average sales price of $12.50 per share. The Operating Partnership used the net proceeds contributed to it by the Parent Company to repay balances on credit facilities and for general corporate purposes.

Common Unit Repurchases

The Parent Company did not repurchase any shares under its share repurchase program during the nine-month period ended September 30, 2013 and accordingly, during the nine-month period ended September 30, 2012, the Operating Partnership did not repurchase any units in connection with the Parent Company’s share repurchase program.

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Non Controlling Interests In the Parent Company

9 Months Ended

Sep. 30, 2013

Noncontrolling Interest [Abstract]

NON-CONTROLLING INTERESTS IN THE PARENT COMPANY [Text Block]

NON-CONTROLLING INTERESTS IN THE PARENT COMPANY

Non-controlling interests in the Parent Company’s financial statements relate to redeemable common limited partnership interests in the Operating Partnership held by parties other than the Parent Company.

As of September 30, 2013 and December 31, 2012, the aggregate book value of the non-controlling interests associated with the redeemable common limited partnership interests in the accompanying consolidated balance sheet of the Parent Company was $20.3 million and $21.2 million, respectively. The Parent Company believes that the aggregate settlement value of these interests (based on the number of units outstanding and the closing price of the common shares on the balance sheet date) was approximately $23.2 million and $22.5 million, respectively, as of September 30, 2013 and December 31, 2012.

XML

Document and Entity Information Document	9 Months Ended
	Sep. 30, 2013	Oct. 29, 2013
Document Information [Line Items]
Entity Registrant Name	BRANDYWINE REALTY TRUST
Entity Central Index Key	0000790816
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Common Stock, Shares Outstanding		156,710,290
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Document Information [Line Items]
Entity Registrant Name	BRANDYWINE OPERATING PARTNERSHIP, L.P.
Entity Central Index Key	0001060386
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	Sep. 30, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes

XML

Beneficiaries Equity of the Parent Company

9 Months Ended

Sep. 30, 2013

Equity [Abstract]

BENEFICIARIES' EQUITY OF THE PARENT COMPANY [Text Block]

BENEFICIARIES’ EQUITY OF THE PARENT COMPANY

Earnings per Share (EPS)

The following tables detail the number of shares and net income used to calculate basic and diluted earnings per share (in thousands, except share and per share amounts; results may not add due to rounding):

	Three-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income from continuing operations	$	11,174		$	11,174		$	5,500		$	5,500
Net (income) from continuing operations attributable to non-controlling interests	(106		)	(106		)	(49		)	(49		)
Amount allocable to unvested restricted shareholders	(85		)	(85		)	(95		)	(95		)
Preferred share dividends	(1,725		)	(1,725		)	(2,785		)	(2,785		)
Income from continuing operations available to common shareholders	9,258			9,258			2,571			2,571
Income (Loss) from discontinued operations	(86		)	(86		)	11,589			11,589
Discontinued operations attributable to non-controlling interests	1			1			(211		)	(211		)
Discontinued operations attributable to common shareholders	(85		)	(85		)	11,378			11,378
Net income attributable to common shareholders	$	9,173		$	9,173		$	13,949		$	13,949
Denominator
Weighted-average shares outstanding	156,703,348			156,703,348			143,424,485			143,424,485
Contingent securities/Share based compensation	—			1,288,734			—			703,525
Total weighted-average shares outstanding	156,703,348			157,992,082			143,424,485			144,128,010
Earnings per Common Share:
Income from continuing operations attributable to common shareholders	$	0.06		$	0.06		$	0.02		$	0.02
Discontinued operations attributable to common shareholders	—			—			0.08			0.08
Net income attributable to common shareholders	$	0.06		$	0.06		$	0.10		$	0.10

	Nine-month periods ended September 30,
	2013						2012
	Basic			Diluted			Basic			Diluted
Numerator
Income (Loss) from continuing operations	$	18,568		$	18,568		$	(8,350	)	$	(8,350	)
Net (income) loss from continuing operations attributable to non-controlling interests	(147		)	(147		)	335			335
Amount allocable to unvested restricted shareholders	(278		)	(278		)	(286		)	(286		)
Preferred share dividends	(5,175		)	(5,175		)	(7,832		)	(7,832		)
Preferred share redemption charge	—			—			(2,090		)	(2,090		)
Income (Loss) from continuing operations available to common shareholders	12,968			12,968			(18,223		)	(18,223		)
Income from discontinued operations	3,619			3,619			41,577			41,577
Discontinued operations attributable to non-controlling interests	(48		)	(48		)	(760		)	(760		)
Discontinued operations attributable to common shareholders	3,571			3,571			40,817			40,817
Net income attributable to common shareholders	$	16,539		$	16,539		$	22,594		$	22,594
Denominator
Weighted-average shares outstanding	151,933,441			151,933,441			143,182,911			143,182,911
Contingent securities/Share based compensation	—			1,209,384			—			—
Total weighted-average shares outstanding	151,933,441			153,142,825			143,182,911			143,182,911
Earnings per Common Share:
Income (Loss) from continuing operations attributable to common shareholders	$	0.09		$	0.09		$	(0.13	)	$	(0.13	)
Discontinued operations attributable to common shareholders	0.02			0.02			0.29			0.29
Net income attributable to common shareholders	$	0.11		$	0.11		$	0.16		$	0.16

Redeemable common limited partnership units totaling 1,763,739 and 2,657,721 as of September 30, 2013 and 2012, respectively, were excluded from the diluted earnings per share computations because their effect would have been anti-dilutive.

The contingent securities/share based compensation impact is calculated using the treasury stock method and relates to employee awards settled in shares of the Parent Company. The effect of these securities is anti-dilutive for periods that the Parent Company incurs a net loss from continuing operations available to common shareholders and therefore is excluded from the dilutive earnings per share calculation in such periods.

Unvested restricted shares are considered participating securities which require the use of the two-class method for the computation of basic and diluted earnings per share. For the nine months ended September 30, 2013 and 2012, earnings representing nonforfeitable dividends as noted in the table above were allocated to the unvested restricted shares issued to the Company’s executives and other employees under the 1997 Plan.

Common and Preferred Shares

On September 10, 2013, the Parent Company declared a distribution of $0.15 per common share, totaling $23.8 million, which was paid on October 18, 2013 to shareholders of record as of October 4, 2013. On September 10, 2013, the Parent Company declared distributions on its Series E Preferred Shares to holders of record as of September 30, 2013. These shares are entitled to a preferential return of 6.90% per annum on the $25.00 per share liquidation preference. Distributions paid on October 15, 2013 to holders of Series E Preferred Shares totaled $1.7 million.

On April 10, 2013, the Parent Company closed a public offering of 12,650,000 common shares, inclusive of 1,650,000 common shares issued upon exercise by the underwriters of the option granted to them to purchase additional shares. The Parent Company contributed the net proceeds from the sale of shares, amounting to $181.7 million after deducting underwriting discounts and commissions and other offering expenses, to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership continues to use the net proceeds for working capital, capital expenditures and other general corporate purposes, which may include acquisitions, developments and the repayment, repurchase and refinancing of debt.

In March 2010, the Parent Company commenced a continuous equity offering program (the “Offering Program”), that provided for the Parent Company's sale, from time to time until the Offering Program's expiration on March 10, 2013, of up to an aggregate of 15,000,000 common shares in amounts and at times determined by the Parent Company. The Parent Company determined to sell shares under the Offering Program based on a variety of factors, including the trading price of its common shares, overall market conditions and the Parent Company's needs for and assessment of alternative sources of capital. Under the Offering Program, the Parent Company engaged sales agents, who received compensation of up to 2% of the gross sales price per share sold. From January 1, 2013 through the expiration of the Offering Program, the Parent Company did not sell any shares under the Offering Program. From the inception of the Offering Program in March 2010 through its expiration, the Parent Company sold an aggregate of 6,421,553 common shares under the Offering Program at an average sales price of $12.50 per share. The Parent Company contributed the net proceeds from the sale of its shares to the Operating Partnership in exchange for the issuance of 6,421,553 common partnership units to the Parent Company. The Operating Partnership used the net proceeds contributed to it by the Parent Company to repay balances on credit facilities and for general corporate purposes.

Common Share Repurchases

The Parent Company maintains a share repurchase program under which it may repurchase its common shares from time to time in accordance with limits set by the Board of Trustees.

The Parent Company did not repurchase any shares under the share repurchase program during the nine-month period ended September 30, 2013. As of September 30, 2013, the Parent Company may purchase an additional 539,200 shares under the current program limits.

Repurchases may be made from time to time in the open market or in privately negotiated transactions, subject to market conditions and compliance with legal requirements. The share repurchase program does not contain any time limitation and does not obligate the Parent Company to repurchase any shares. The Parent Company may discontinue the program at any time.

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Fair Value of Financial Instruments Fair Value of Financial Instruments (Details Textuals) (Details)	Sep. 30, 2013
Fair Value Disclosures [Abstract]
Weighted Average Fair Value Interest Rate on Debt	3.337%

XML

Fair Value of Financial Instruments Fair Value of Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Company's estimates of fair value differ from the carrying amounts
Mortgage notes payable, Carrying Amount	$ 435,590	$ 443,942
Mortgage notes payable, Fair Value	473,614	486,412
Unsecured Notes Payable, Carrying Amount	1,418,443	1,430,343
Unsecured Notes Payable, Fair Value	1,499,166	1,553,123
Variable Rate Debt, Carrying Amount	528,610	597,610
Variable Rate Debt, Fair Value	526,693	595,693
Notes Receivable, Carrying Amount	7,026	7,226
Notes Receivable, Fair Value	$ 7,491	$ 7,783