Biomed Realty Trust 10-K 10 Feb 14 2013 Q4 Annual report Financial data

Document_Entity_Information

Document Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Feb. 07, 2014	Jun. 28, 2013
Entity Information [Line Items]	'	'	'
Entity Registrant Name	'BioMed Realty Trust Inc	'	'
Entity Central Index Key	'0001289236	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Large Accelerated Filer	'	'
Document Type	'10-K	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'Q4	'	'
Amendment Flag	'false	'	'
Entity Common Stock, Shares Outstanding	'	192,571,286	'
Entity Well-known Seasoned Issuer	'Yes	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Public Float	'	'	$3,857,212,568
BIOMED REALTY, L.P.	'	'	'
Entity Information [Line Items]	'	'	'
Entity Registrant Name	'BioMed Realty L P	'	'
Entity Central Index Key	'0001301932	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Non-accelerated Filer	'	'
Document Type	'10-K	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Year Focus	'2013	'	'
Document Fiscal Period Focus	'Q4	'	'
Amendment Flag	'false	'	'

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Investments in real estate, net	$5,217,902	$4,319,716
Investments in unconsolidated partnerships	32,137	32,367
Parent Company	'	'
Income (Loss) from Continuing Operations, Per Basic and Diluted Share	$0.20	'
Investments in real estate, net	5,217,902	4,319,716
Investments in unconsolidated partnerships	32,137	32,367
Cash and cash equivalents	34,706	19,976
Accounts receivable, net	8,421	4,507
Accrued straight-line rents, net	173,779	152,096
Deferred leasing costs, net	198,067	172,363
Other assets	307,589	133,454
Total assets	5,972,601	4,834,479
Liabilities [Abstract]	'	'
Mortgage notes payable, net	709,324	571,652
Exchangeable senior notes	180,000	180,000
Unsecured senior notes, net	895,083	894,177
Unsecured senior term loans	758,786	405,456
Unsecured line of credit	128,000	118,000
Accounts payable, accrued expenses and other liabilities	314,383	180,653
Total liabilities	2,985,576	2,349,938
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]	'	'
Preferred stock, $.01 par value, 15,000,000 shares authorized: 7.375% Series A cumulative redeemable preferred stock, no shares issued and outstanding at December 31, 2013; and 7,920,000 shares issued and outstanding at December 31, 2012, $198,000 liquidation preference ($25.00 per share)	'	191,469
Common stock, $.01 par value, 250,000,000 shares authorized, 192,115,002 shares issued and outstanding at December 31, 2013; and 200,000,000 shares authorized, 154,327,818 shares issued and outstanding at December 31, 2012	1,921	1,543
Additional paid-in capital	3,554,558	2,781,849
Accumulated other comprehensive loss, net	-32,923	-54,725
Dividends in excess of earnings	-583,569	-443,280
Total stockholders' equity	2,939,987	2,476,856
Noncontrolling interests / Noncontrolling interests deficit	47,038	7,685
Total equity / capital	2,987,025	2,484,541
Total liabilities and equity / capital	5,972,601	4,834,479
BIOMED REALTY, L.P.	'	'
Income (Loss) from Continuing Operations, Per Basic and Diluted Share	$0.20	'
Investments in real estate, net	5,217,902	4,319,716
Investments in unconsolidated partnerships	32,137	32,367
Cash and cash equivalents	34,706	19,976
Accounts receivable, net	8,421	4,507
Accrued straight-line rents, net	173,779	152,096
Deferred leasing costs, net	198,067	172,363
Other assets	307,589	133,454
Total assets	5,972,601	4,834,479
Liabilities [Abstract]	'	'
Mortgage notes payable, net	709,324	571,652
Exchangeable senior notes	180,000	180,000
Unsecured senior notes, net	895,083	894,177
Unsecured senior term loans	758,786	405,456
Unsecured line of credit	128,000	118,000
Accounts payable, accrued expenses and other liabilities	314,383	180,653
Total liabilities	2,985,576	2,349,938
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]	'	'
Preferred units, 7.375% Series A cumulative redeemable preferred units, no units issued and outstanding at December 31, 2013; and 7,920,000 units issued and outstanding at December 31, 2012, $198,000 liquidation preference ($25.00 per unit)	'	191,469
Limited partners' capital, 5,415,974 and 2,932,758 units issued and outstanding at December 31, 2013 and December 31, 2012, respectively	45,708	7,937
General partner's capital, 192,115,002 and 154,327,818 units issued and outstanding at December 31, 2013 and December 31, 2012, respectively	2,970,650	2,338,464
Accumulated other comprehensive loss, net	-30,663	-53,077
Total partners' capital	2,985,695	2,484,793
Noncontrolling interests / Noncontrolling interests deficit	1,330	-252
Total equity / capital	2,987,025	2,484,541
Total liabilities and equity / capital	$5,972,601	$4,834,479

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parentheticals) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Parent Company	'	'
Preferred Stock, Par or Stated Value Per Share	0.01	0.01
Preferred Stock, Shares Authorized	15,000,000	15,000,000
Preferred Stock Liquidation Preference Total	'	198,000,000
Preferred Stock, Liquidation Preference Per Share	25	25
Preferred Stock, Shares Issued	'	7,920,000
Preferred Stock, Shares Outstanding	'	7,920,000
Common Stock, Par or Stated Value Per Share	0.01	0.01
Common Stock, Shares Authorized	250,000,000	200,000,000
Common Stock, Shares, Issued	192,115,002	154,327,818
BIOMED REALTY, L.P.	'	'
Limited Partners' Capital Account, Units Issued	5,415,974	2,932,758
Limited Partners' Capital Account, Units Outstanding	5,415,974	2,932,758
General Partners' Capital Account, Units Issued	192,115,002	154,327,818
General Partners' Capital Account, Units Outstanding	192,115,002	154,327,818
Common Stock | Parent Company	'	'
Common Stock, Shares Outstanding	192,115,002	154,327,818

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues:	'	'	'
Total revenues	$45,300	'	'
Expenses:	'	'	'
Equity in net loss of unconsolidated partnerships	-905	-1,389	-2,489
Income / (loss) from discontinued operations	0	-4,370	474
Net income / (loss)	-2,600	'	'
Parent Company	'	'	'
Revenues:	'	'	'
Rental	445,980	392,628	329,454
Tenant recoveries	141,634	120,793	101,965
Other revenue	49,700	4,746	6,781
Total revenues	637,314	518,167	438,200
Expenses:	'	'	'
Rental operations	184,073	152,219	128,146
Depreciation and amortization	245,000	196,844	142,319
General and administrative	44,175	38,025	30,966
Acquisition-related expenses	5,282	13,077	1,099
Total expenses	478,530	400,165	302,530
Income from operations	158,784	118,002	135,670
Equity in net loss of unconsolidated partnerships	-905	-1,389	-2,489
Interest expense, net	-107,727	-99,608	-89,181
Other expense	-2,943	-872	-1,760
Income / (loss) from continuing operations	47,209	16,133	42,240
Income / (loss) from discontinued operations	'	-4,370	474
Net income / (loss)	47,209	11,763	42,714
Net (income) / loss attributable to noncontrolling interests	-565	62	-525
Net income / (loss) attributable to the Company/Operating Partnership	46,644	11,825	42,189
Preferred stock dividends / unit distributions	-2,393	-14,603	-16,033
Cost on redemption of preferred stock / units	-6,531	'	-165
Net income / (loss) available to common stockholders/unitholders	37,720	-2,778	25,991
Income / (loss) from continuing operations per share / unit available to common stockholders / unitholders	$0.20	'	$0.19
Loss from discontinued operations per share / unit available to common stockholders / unitholders	'	($0.03)	'
Net income / (loss) per share / unit available to common stockholders / unitholders	$0.20	($0.03)	$0.19
Weighted Average Number of Shares Outstanding, Basic	182,043,391	152,752,086	132,625,915
Weighted Average Number of Shares Outstanding, Diluted	186,397,022	155,700,387	135,609,843
BIOMED REALTY, L.P.	'	'	'
Revenues:	'	'	'
Rental	445,980	392,628	329,454
Tenant recoveries	141,634	120,793	101,965
Other revenue	49,700	4,746	6,781
Total revenues	637,314	518,167	438,200
Expenses:	'	'	'
Rental operations	184,073	152,219	128,146
Depreciation and amortization	245,000	196,844	142,319
General and administrative	44,175	38,025	30,966
Acquisition-related expenses	5,282	13,077	1,099
Total expenses	478,530	400,165	302,530
Income from operations	158,784	118,002	135,670
Equity in net loss of unconsolidated partnerships	-905	-1,389	-2,489
Interest expense, net	-107,727	-99,608	-89,181
Other expense	-2,943	-872	-1,760
Income / (loss) from continuing operations	47,209	16,133	42,240
Income / (loss) from discontinued operations	'	-4,370	474
Net income / (loss)	47,209	11,763	42,714
Net (income) / loss attributable to noncontrolling interests	254	8	44
Net income / (loss) attributable to the Company/Operating Partnership	47,463	11,771	42,758
Preferred stock dividends / unit distributions	-2,393	-14,603	-16,033
Cost on redemption of preferred stock / units	-6,531	'	-165
Net income / (loss) available to common stockholders/unitholders	$38,539	($2,832)	$26,560
Income / (loss) from continuing operations per share / unit available to common stockholders / unitholders	$0.20	'	$0.19
Loss from discontinued operations per share / unit available to common stockholders / unitholders	'	($0.03)	'
Net income / (loss) per share / unit available to common stockholders / unitholders	$0.20	($0.03)	$0.19
Weighted Average Number of Shares Outstanding, Basic	186,333,292	155,670,931	135,549,934
Weighted Average Number of Shares Outstanding, Diluted	186,396,309	155,670,931	135,549,934

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Net income / (loss)	($2,600)	'	'
Other Comprehensive Income (Loss), Net of Tax	24,250	'	'
Parent Company	'	'	'
Net income / (loss)	47,209	11,763	42,714
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	395	3,611	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	6,116	-5,144	3,857
Amortization of Other Deferred Charges	6,832	6,933	7,027
Other Comprehensive Income (Loss), Reclassification Adjustment for Write-down of Securities Included in Net Income, Net of Tax	'	545	5,132
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	'	-38	70
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss), Net of Tax	10,907	-390	-5,131
Other Comprehensive Income (Loss), Net of Tax	24,250	5,517	10,955
Comprehensive Income / loss, Net of Tax, Including Portion Attributable to Noncontrolling Interest	71,459	17,280	53,669
Comprehensive (income) / loss, Net of Tax, Attributable to Noncontrolling Interest	-3,013	-42	-760
Comprehensive income / (loss), Net of Tax, Attributable to Parent	68,446	17,238	52,909
BIOMED REALTY, L.P.	'	'	'
Net income / (loss)	47,209	11,763	42,714
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	395	3,611	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	6,116	-5,144	3,857
Amortization of Other Deferred Charges	6,832	6,933	7,027
Other Comprehensive Income (Loss), Reclassification Adjustment for Write-down of Securities Included in Net Income, Net of Tax	'	545	5,132
Other Comprehensive Income (Loss), Reclassification Adjustment for Sale of Securities Included in Net Income, Net of Tax	'	-38	70
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss), Net of Tax	10,907	-390	-5,131
Other Comprehensive Income (Loss), Net of Tax	24,250	5,517	10,955
Comprehensive Income / loss, Net of Tax, Including Portion Attributable to Noncontrolling Interest	71,459	17,280	53,669
Comprehensive (income) / loss, Net of Tax, Attributable to Noncontrolling Interest	-1,582	8	44
Comprehensive income / (loss), Net of Tax, Attributable to Parent	69,877	17,288	53,713
Interest Rate Swaps | Parent Company	'	'	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	6,116	-5,144	3,857
Interest Rate Swaps | BIOMED REALTY, L.P.	'	'	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax	$6,116	'	'

Consolidated_Statement_of_Equi

Consolidated Statement of Equity (USD $)

Total

Parent Company

BIOMED REALTY, L.P.

Series A Preferred Stock

Series A Preferred Stock

Common Stock

Common Stock

Additional Paid-In Capital

Accumulated Other Comprehensive (Loss)/Income

Accumulated Other Comprehensive (Loss)/Income

Dividends in Excess of Earnings

Total Stockholders'/Partner's Equity

Total Stockholders'/Partner's Equity

Total Stockholders'/Partner's Equity

Noncontrolling Interest

Noncontrolling Interest

Limited Partner

Limited Partner

General Partner [Member]

Forward Starting Swaps

Forward Starting Swaps

Interest Rate Swaps

Interest Rate Swaps

In Thousands, except Share data

USD ($)

USD ($)

USD ($)

Parent Company

BIOMED REALTY, L.P.

Parent Company

Parent Company

Parent Company

BIOMED REALTY, L.P.

Parent Company

Parent Company

Noncontrolling Interest

BIOMED REALTY, L.P.

Parent Company

BIOMED REALTY, L.P.

Common Stock

Common Stock

Common Stock

Parent Company

BIOMED REALTY, L.P.

Parent Company

BIOMED REALTY, L.P.

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Balance - value - period start at Dec. 31, 2010

'

$2,312,896

$2,312,896

$222,413

$222,413

'

$1,310

$2,371,488

($70,857)

($69,549)

($221,176)

$2,303,178

'

$2,313,096

$9,718

($200)

'

$9,918

$2,150,314

'

'

'

'

Balance - units - period start at Dec. 31, 2010

'

'

'

'

9,200,000

'

'

'

'

'

'

'

'

'

'

'

'

3,001,250

131,046,509

'

'

'

'

Balance - shares - period start at Dec. 31, 2010

'

'

'

'

'

'

131,046,509

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Shares, New Issues

'

'

'

'

'

'

22,562,922

'

'

'

'

'

'

'

'

'

'

'

22,562,922

'

'

'

'

Stock Issued During Period, Value, New Issues

'

399,571

399,571

'

'

'

225

399,346

'

'

'

399,571

'

399,571

'

'

'

'

399,571

'

'

'

'

Net issuances of unvested restricted common stock/OP units - shares

'

'

'

'

'

'

470,780

'

'

'

'

'

'

'

'

'

'

'

470,780

'

'

'

'

Net issuances of unvested restricted common stock/OP units - value

'

-2,420

-2,420

'

'

'

5

-2,425

'

'

'

-2,420

'

-2,420

'

'

'

'

-2,420

'

'

'

'

Conversion of OP units to common stock - shares

'

'

'

'

'

'

-21,271

'

'

'

'

'

'

'

'

'

'

-21,271

-21,271

'

'

'

'

Conversion of OP units to common stock - value

'

'

'

'

'

'

1

-50

'

'

'

-49

'

'

49

'

'

49

-49

'

'

'

'

Partners' Capital Account, Units, Redeemed

'

'

'

'

-1,280,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred Stock Redemption Premium

'

31,109

31,109

30,944

31,109

'

'

'

'

'

165

31,109

'

31,109

'

'

'

'

'

'

'

'

'

Vesting of share-based awards

'

7,582

7,582

'

'

'

'

7,582

'

'

'

7,582

'

7,582

'

'

'

'

7,582

'

'

'

'

Reallocation of equity to noncontrolling interests/limited partners

'

'

'

'

'

'

'

-1,947

'

'

'

-1,947

'

'

1,947

'

'

2,182

-2,182

'

'

'

'

Common stock dividends

'

-109,574

'

'

'

'

'

'

'

'

-109,574

-109,574

'

'

'

'

'

'

'

'

'

'

'

OP unit distributions

'

-2,386

-127,993

'

-16,033

'

'

'

'

'

'

'

'

-127,993

-2,386

'

'

-2,386

-109,574

'

'

'

'

Net income / (loss)

'

42,714

42,714

'

16,198

'

'

'

'

'

42,189

42,189

'

42,758

525

-44

'

569

25,991

'

'

'

'

Preferred stock dividends/unit distributions

'

-16,033

'

'

'

'

'

'

'

'

-16,033

-16,033

'

'

'

'

'

'

'

'

'

'

'

Unrealized loss on equity securities

'

-5,131

-5,131

'

'

'

'

'

-5,021

-5,131

'

-5,021

'

-5,131

-110

'

'

'

'

'

'

'

'

Amortization of deferred interest costs

'

'

7,027

'

'

'

'

'

6,877

7,027

'

6,877

'

7,027

150

'

'

'

'

7,027

'

'

'

Unrealized gain on derivative instruments, net

'

3,857

3,857

'

'

'

'

'

3,773

3,857

'

3,773

'

3,857

84

'

'

'

'

'

'

3,857

'

Other Comprehensive Income (Loss), Reclassification Adjustment for Write-down of Securities Included in Net Income, Net of Tax

'

5,132

5,132

'

'

'

'

'

5,021

5,132

'

5,021

'

5,132

111

'

'

'

'

'

'

'

'

Marketable Securities, Realized Gain (Loss)

'

70

70

'

'

'

'

'

69

70

'

69

1

70

'

'

'

'

'

'

'

'

'

Balance - value - period end at Dec. 31, 2011

'

2,612,196

2,612,196

191,469

191,469

'

1,541

2,773,994

-60,138

-58,594

-304,759

2,602,107

'

2,612,440

10,089

-244

'

10,332

2,469,233

'

'

'

'

Balance - units - period end at Dec. 31, 2011

'

'

'

'

7,920,000

'

'

'

'

'

'

'

'

'

'

'

'

2,979,979

154,101,482

'

'

'

'

Balance - shares - period end at Dec. 31, 2011

'

'

'

'

'

'

154,101,482

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net income / (loss)

[1]

'

2,282

2,282

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period end at Mar. 31, 2012

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period start at Dec. 31, 2011

'

2,612,196

2,612,196

'

191,469

'

1,541

2,773,994

-60,138

-58,594

-304,759

2,602,107

'

2,612,440

10,089

-244

'

10,332

2,469,233

'

'

'

'

Balance - units - period start at Dec. 31, 2011

'

'

'

'

7,920,000

'

'

'

'

'

'

'

'

'

'

'

'

2,979,979

154,101,482

'

'

'

'

Balance - shares - period start at Dec. 31, 2011

'

'

'

'

'

'

154,101,482

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net issuances of unvested restricted common stock/OP units - shares

'

'

'

'

'

'

179,115

'

'

'

'

'

'

'

'

'

'

'

179,115

'

'

'

'

Net issuances of unvested restricted common stock/OP units - value

'

-3,528

-3,528

'

'

'

1

-3,529

'

'

'

-3,528

'

-3,528

'

'

'

'

-3,528

'

'

'

'

Conversion of OP units to common stock - shares

'

'

'

'

'

'

-47,221

'

'

'

'

'

'

'

'

'

'

-47,221

-47,221

'

'

'

'

Conversion of OP units to common stock - value

'

'

'

'

'

'

1

'

'

'

'

1

'

'

-1

'

'

-1

1

'

'

'

'

Vesting of share-based awards

'

11,530

11,530

'

'

'

'

11,530

'

'

'

11,530

'

11,530

'

'

'

'

11,530

'

'

'

'

Reallocation of equity to noncontrolling interests/limited partners

'

'

'

'

'

'

'

-146

'

'

'

-146

'

'

146

'

'

251

-251

'

'

'

'

Common stock dividends

'

-135,743

'

'

'

'

'

'

'

'

-135,743

-135,743

'

'

'

'

'

'

'

'

'

'

'

OP unit distributions

'

-2,591

-152,937

'

-14,603

'

'

'

'

'

'

'

'

-152,937

-2,591

'

'

-2,591

-135,743

'

'

'

'

Net income / (loss)

'

11,763

11,763

'

14,603

'

'

'

'

'

11,825

11,825

'

11,771

-62

-8

'

-54

-2,778

'

'

'

'

Preferred stock dividends/unit distributions

'

-14,603

'

'

'

'

'

'

'

'

-14,603

-14,603

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Foreign currency translation adjustment

'

3,611

3,611

'

'

'

'

'

3,543

3,611

'

3,543

'

3,611

68

'

'

'

'

'

'

'

'

Unrealized loss on equity securities

'

-390

-390

'

'

'

'

'

-382

-390

'

-382

'

-390

-8

'

'

'

'

'

'

'

'

Amortization of deferred interest costs

'

'

6,933

'

'

'

'

'

6,803

6,933

'

6,803

'

6,933

130

'

'

'

'

6,933

'

'

'

Unrealized gain on derivative instruments, net

'

-5,144

-5,144

'

'

'

'

'

-5,048

-5,144

'

-5,048

'

-5,144

-96

'

'

'

'

'

'

-5,144

'

Other Comprehensive Income (Loss), Reclassification Adjustment for Write-down of Securities Included in Net Income, Net of Tax

'

545

545

'

'

'

'

'

535

545

'

535

'

545

10

'

'

'

'

'

'

'

'

Marketable Securities, Realized Gain (Loss)

'

-38

-38

'

'

'

'

'

-38

-38

'

-38

'

-38

'

'

'

'

'

'

'

'

'

Balance - value - period end at Dec. 31, 2012

'

2,484,541

2,484,541

'

191,469

'

1,543

2,781,849

-54,725

-53,077

-443,280

2,476,856

'

2,484,793

7,685

-252

'

7,937

2,338,464

'

'

'

'

Balance - units - period end at Dec. 31, 2012

'

'

'

'

7,920,000

'

'

'

'

'

'

'

'

'

'

'

'

2,932,758

154,327,818

'

'

'

'

Balance - shares - period end at Dec. 31, 2012

'

'

'

'

'

'

154,327,818

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period start at Sep. 30, 2012

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net income / (loss)

[1]

'

8,260

8,260

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period end at Dec. 31, 2012

'

2,484,541

2,484,541

'

'

'

1,543

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - shares - period start at Dec. 31, 2012

'

'

'

'

'

'

154,327,818

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Shares, New Issues

'

'

'

'

'

'

14,605,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Value, New Issues

'

287,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net income / (loss)

[1]

'

17,458

17,458

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period end at Mar. 31, 2013

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period start at Dec. 31, 2012

'

2,484,541

2,484,541

191,469

191,469

'

1,543

2,781,849

-54,725

-53,077

-443,280

2,476,856

'

2,484,793

7,685

-252

'

7,937

2,338,464

'

'

'

'

Balance - units - period start at Dec. 31, 2012

'

'

'

'

7,920,000

'

'

'

'

'

'

'

'

'

'

'

'

2,932,758

154,327,818

'

'

'

'

Balance - shares - period start at Dec. 31, 2012

'

'

'

'

'

'

154,327,818

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Shares, New Issues

'

'

'

'

'

'

31,855,000

'

'

'

'

'

'

'

'

'

'

2,034,211

31,855,000

'

'

'

'

Stock Issued During Period, Value, New Issues

'

641,097

682,615

'

'

'

319

640,778

'

'

'

641,097

'

682,615

'

'

'

41,518

641,097

'

'

'

'

Net issuances of unvested restricted common stock/OP units - shares

'

'

'

'

'

'

343,561

'

'

'

'

'

'

'

'

'

'

132,441

343,561

'

'

'

'

Net issuances of unvested restricted common stock/OP units - value

'

-5,050

-5,050

'

'

'

3

-5,053

'

'

'

-5,050

'

-5,050

'

'

'

'

-5,050

'

'

'

'

Conversion of OP units to common stock - shares

'

'

'

'

'

'

-20,396

'

'

'

'

'

'

'

'

'

'

-20,396

-20,396

'

'

'

'

Conversion of OP units to common stock - value

'

'

'

'

'

'

'

-87

'

'

'

-87

'

'

87

'

'

87

-87

'

'

'

'

Partners' Capital Account, Units, Redeemed

'

'

'

'

-7,920,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred Stock Redemption Premium

'

198,000

198,000

191,469

198,000

'

'

'

'

'

6,531

198,000

'

198,000

'

'

'

'

'

'

'

'

'

Vesting of share-based awards

'

12,852

12,852

'

'

'

'

12,852

'

'

'

12,852

'

12,852

'

'

'

'

12,852

'

'

'

'

Stock Issued During Period, Units, Issued in Connection with Wexford Merger

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

336,960

336,960

5,568,227

'

'

'

'

Stock Issued During Period, Value, Issued in Connection with Wexford Merger

'

'

123,596

'

'

'

'

'

'

'

'

'

'

123,596

'

'

'

7,053

116,543

'

'

'

'

Stock Issued During Period, Merger Issues

'

'

'

'

'

5,568,227

5,568,227

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Value, Wexford Merger

'

116,543

'

'

'

'

56

116,487

'

'

'

116,543

'

'

'

'

'

'

'

'

'

'

'

Noncontrolling Interest, Increase from Business Combination

'

48,571

'

'

'

'

'

'

'

'

'

'

'

'

48,571

'

'

'

'

'

'

'

'

Reallocation of equity to noncontrolling interests/limited partners

'

'

'

'

'

'

'

7,732

'

'

'

7,732

'

'

-7,732

'

'

-7,120

7,120

'

'

'

'

Common stock dividends

'

-178,009

'

'

'

'

'

'

'

'

-178,009

-178,009

'

'

'

'

'

'

'

'

'

'

'

OP unit distributions

'

-4,586

-184,988

'

-2,393

'

'

'

'

'

'

'

'

-184,988

-4,586

'

'

-4,586

-178,009

'

'

'

'

Net income / (loss)

-2,600

47,209

47,209

'

8,924

'

'

'

'

'

46,644

46,644

'

47,463

565

-254

'

819

37,720

'

'

'

'

Preferred stock dividends/unit distributions

'

-2,393

'

'

'

'

'

'

'

'

-2,393

-2,393

'

'

'

'

'

'

'

'

'

'

'

Other Comprehensive Income (Loss), Foreign currency translation adjustment

'

395

395

'

'

'

'

'

362

395

'

362

'

395

33

'

'

'

'

'

'

'

'

Unrealized loss on equity securities

'

10,907

10,907

'

'

'

'

'

8,824

9,071

'

8,824

'

9,071

2,083

1,836

'

'

'

'

'

'

'

Amortization of deferred interest costs

'

'

'

'

'

'

'

'

6,665

6,832

'

6,665

'

6,832

167

'

'

'

'

6,832

6,832

'

'

Unrealized gain on derivative instruments, net

'

6,116

6,116

'

'

'

'

'

5,951

6,116

'

5,951

'

6,116

165

'

'

'

'

'

'

6,116

6,116

Marketable Securities, Realized Gain (Loss)

'

'

0

'

'

'

'

'

'

0

'

'

'

0

'

'

'

'

'

'

'

'

'

Balance - value - period end at Dec. 31, 2013

'

2,987,025

2,987,025

'

'

'

1,921

3,554,558

-32,923

-30,663

-583,569

2,939,987

'

2,985,695

47,038

1,330

'

45,708

2,970,650

'

'

'

'

Balance - units - period end at Dec. 31, 2013

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,415,974

192,115,002

'

'

'

'

Balance - shares - period end at Dec. 31, 2013

'

'

'

'

'

'

192,115,002

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period start at Sep. 30, 2013

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Net income / (loss)

[1]

'

10,576

10,576

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Balance - value - period end at Dec. 31, 2013

'

$2,987,025

$2,987,025

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

[1]

The sum of quarterly financial data may vary from the annual data due to rounding.

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating Activities	'	'	'
Net income / (loss)	($2,600)	'	'
Adjustments to reconcile net income to net cash provided by operating activities	'	'	'
Allowance for doubtful accounts	931	1,700	2,300
BIOMED REALTY, L.P.	'	'	'
Interest Paid, Capitalized	14,205	8,644	'
Operating Activities	'	'	'
Net income / (loss)	47,209	11,763	42,714
Adjustments to reconcile net income to net cash provided by operating activities	'	'	'
Depreciation and amortization	245,000	196,927	142,681
Allowance for doubtful accounts	931	1,656	2,277
Non-cash revenue adjustments	9,870	11,261	10,400
Other non-cash adjustments	9,095	19,027	9,130
Compensation expense related to restricted common stock and LTIP units / share-based payments	12,852	11,530	7,582
Distributions representing a return on capital from unconsolidated partnerships	237	1,202	2,428
Change in operating assets and liabilities	'	'	'
Accounts receivable	-2,958	282	-1,308
Accrued straight-line rents	-22,027	-23,044	-24,925
Deferred leasing costs	-13,597	-13,993	-12,583
Other assets	-2,798	2,748	2,640
Accounts payable, accrued expenses and other liabilities	-4,025	18,876	-6,005
Net cash provided by operating activities	279,789	238,235	175,031
Investing activities	'	'	'
Purchases of investments in real estate and related intangible assets	-480,049	-366,492	-393,481
Capital expenditures	-252,128	-138,870	-143,354
Contributions from historic tax credit transactions, net of deferred costs	23,334	'	'
Contributions from new market tax credit transactions, net of deferred costs	11,251	'	'
Draws on construction loan receivable	-124,048	-21,697	'
Contributions to unconsolidated partnerships, net	-1,730	-2,410	-54,436
Purchases of debt and equity securities	-16,081	-8,645	-5,245
Proceeds from the sale of debt and equity securities	6,232	132	125
Payments for (Proceeds from) Deposits on Real Estate Acquisitions	'	'	-7,940
Net cash used in investing activities	-833,219	-537,982	-604,331
Financing activities	'	'	'
Proceeds from issuance of OP units	641,097	'	399,571
Redemption of Series A preferred stock	-198,000	'	-31,109
Payments of deferred loan costs	-6,947	-5,937	-9,733
Unsecured line of credit proceeds	805,000	596,000	771,575
Unsecured line of credit payments	-795,000	-746,000	-896,025
Mortgage notes proceeds	4,182	'	'
Principal payments on mortgage notes payable	-115,542	-41,196	-67,741
Proceeds from unsecured senior term loans	350,000	556,404	'
Unsecured senior term loan payments	'	-156,404	'
Repayments of Convertible Debt	'	'	-19,800
Proceeds from unsecured senior notes	'	247,815	397,460
Release of restriction of cash for repayment of debt	60,000	'	'
Dividends paid to common stockholders / unitholders	-170,169	-132,796	-103,331
Dividends paid to preferred stockholders / unitholders	-6,045	-14,601	-16,623
Net cash provided by financing activities	568,576	303,285	424,244
Effect of exchange rate changes on cash and cash equivalents	-416	27	'
Net increase / (decrease) in cash and cash equivalents	14,730	3,565	-5,056
Cash and cash equivalents at beginning of period	19,976	16,411	21,467
Cash and cash equivalents at end of period	34,706	19,976	16,411
Supplemental disclosure of cash flow information:	'	'	'
Cash paid during the period for interest (net of amounts capitalized of $9,999 and $6,376 during the nine months ended September 30, 2013 and 2012, respectively)	94,938	81,868	76,005
Supplemental disclosure of non-cash investing and financing activities:	'	'	'
Accrual for preferred stock dividends / unit distributions declared	'	3,651	3,651
Accrual for common stock dividends / unit distributions declared	49,383	36,957	31,417
Accrued additions to real estate and related intangible assets	56,712	33,153	24,317
Mortgage notes assumed (includes premiums of $8,671 and $1,802 during the nine months ended September 30, 2013 and 2012, respectively)	250,466	25,947	'
Equity issued in connection with Wexford merger and 320 Charles Street acquisition	165,114	'	'
Deposits applied for acquisitions	'	18,649	1,800
Debt Instrument, Unamortized Premium	8,671	1,802	'
Parent Company	'	'	'
Interest Paid, Capitalized	14,205	8,644	'
Operating Activities	'	'	'
Net income / (loss)	47,209	11,763	42,714
Adjustments to reconcile net income to net cash provided by operating activities	'	'	'
Depreciation and amortization	245,000	196,927	142,681
Allowance for doubtful accounts	931	1,656	2,277
Non-cash revenue adjustments	9,870	11,261	10,400
Other non-cash adjustments	9,095	19,027	9,130
Compensation expense related to restricted common stock and LTIP units / share-based payments	12,852	11,530	7,582
Distributions representing a return on capital from unconsolidated partnerships	237	1,202	2,428
Change in operating assets and liabilities	'	'	'
Accounts receivable	-2,958	282	-1,308
Accrued straight-line rents	-22,027	-23,044	-24,925
Deferred leasing costs	-13,597	-13,993	-12,583
Other assets	-2,798	2,748	2,640
Accounts payable, accrued expenses and other liabilities	-4,025	18,876	-6,005
Net cash provided by operating activities	279,789	238,235	175,031
Investing activities	'	'	'
Purchases of investments in real estate and related intangible assets	-480,049	-366,492	-393,481
Capital expenditures	-252,128	-138,870	-143,354
Contributions from historic tax credit transactions, net of deferred costs	23,334	'	'
Contributions from new market tax credit transactions, net of deferred costs	11,251	'	'
Draws on construction loan receivable	-124,048	-21,697	'
Contributions to unconsolidated partnerships, net	-1,730	-2,410	-54,436
Purchases of debt and equity securities	-16,081	-8,645	-5,245
Proceeds from the sale of debt and equity securities	6,232	132	125
Payments for (Proceeds from) Deposits on Real Estate Acquisitions	0	0	-7,940
Net cash used in investing activities	-833,219	-537,982	-604,331
Financing activities	'	'	'
Proceeds from common stock offering	668,553	'	404,328
Payment of offering costs	-27,456	'	-4,757
Redemption of Series A preferred stock	-198,000	'	-31,109
Payments of deferred loan costs	-6,947	-5,937	-9,733
Unsecured line of credit proceeds	805,000	596,000	771,575
Unsecured line of credit payments	-795,000	-746,000	-896,025
Mortgage notes proceeds	4,182	'	'
Principal payments on mortgage notes payable	-115,542	-41,196	-67,741
Proceeds from unsecured senior term loans	350,000	556,404	'
Unsecured senior term loan payments	'	-156,404	'
Repayments of Convertible Debt	'	'	-19,800
Proceeds from unsecured senior notes	'	247,815	397,460
Release of restriction of cash for repayment of debt	60,000	'	'
Distributions to operating partnership unit and LTIP unit holders	-3,921	-2,498	-2,299
Dividends paid to common stockholders / unitholders	-166,248	-130,298	-101,032
Dividends paid to preferred stockholders / unitholders	-6,045	-14,601	-16,623
Net cash provided by financing activities	568,576	303,285	424,244
Effect of exchange rate changes on cash and cash equivalents	-416	27	'
Net increase / (decrease) in cash and cash equivalents	14,730	3,565	-5,056
Cash and cash equivalents at beginning of period	19,976	16,411	21,467
Cash and cash equivalents at end of period	34,706	19,976	16,411
Supplemental disclosure of cash flow information:	'	'	'
Cash paid during the period for interest (net of amounts capitalized of $9,999 and $6,376 during the nine months ended September 30, 2013 and 2012, respectively)	94,938	81,868	76,005
Supplemental disclosure of non-cash investing and financing activities:	'	'	'
Accrual for preferred stock dividends / unit distributions declared	'	3,651	3,651
Accrual for common stock dividends / unit distributions declared	48,029	36,268	30,821
Accrual for distributions declared for operating partnership unit and LTIP unit holders	1,354	689	596
Accrued additions to real estate and related intangible assets	56,712	33,153	24,317
Mortgage notes assumed (includes premiums of $8,671 and $1,802 during the nine months ended September 30, 2013 and 2012, respectively)	250,466	25,947	'
Equity issued in connection with Wexford merger and 320 Charles Street acquisition	165,114	'	'
Deposits applied for acquisitions	'	18,649	1,800
Debt Instrument, Unamortized Premium	$8,671	$1,802	'

Organization_of_the_Parent_Com

Organization of the Parent Company and Description of Business	12 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Organization of the Parent Company and Description of Business	'
	Organization of the Parent Company and Description of Business
	BioMed Realty Trust, Inc., a Maryland corporation (the “Parent Company”), operates as a fully integrated, self-administered and self-managed real estate investment trust (“REIT”) focused on acquiring, developing, owning, leasing and managing laboratory and office space for the life science industry principally through its subsidiary, BioMed Realty, L.P., a Maryland limited partnership (the “Operating Partnership” and together with the Parent Company referred to as the “Company”). The Company’s tenants primarily include biotechnology and pharmaceutical companies, scientific research institutions, government agencies and other entities involved in the life science industry. The Company’s properties are generally located in markets with well-established reputations as centers for scientific research, including Boston, San Francisco, San Diego, Maryland, New York/New Jersey, Pennsylvania, North Carolina, Seattle and Cambridge (United Kingdom) and, through Wexford Science and Technology, LLC and related entities (collectively, "Wexford"), with universities and their related medical systems.
	The Parent Company is the sole general partner of the Operating Partnership and, as of December 31, 2013, owned a 97.3% interest in the Operating Partnership. The remaining 2.7% interest in the Operating Partnership is held by limited partners. Each partner’s percentage interest in the Operating Partnership is determined based on the number of operating partnership units and long-term incentive plan units (“LTIP units” and together with the operating partnership units, the “OP units”) owned as compared to total OP units (and potentially issuable OP units, as applicable) outstanding as of each period end and is used as the basis for the allocation of net income or loss to each partner.
	Information with respect to the square footage and the percent of rentable square feet leased to tenants is unaudited.

Basis_of_Presentation_and_Summ

Basis of Presentation and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Basis of Presentation and Summary of Significant Accounting Policies	'
	Basis of Presentation and Summary of Significant Accounting Policies
	Principles of Consolidation
	The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, partnerships and limited liability companies it controls, and variable interest entities (“VIEs”) for which the Company has determined itself to be the primary beneficiary. All material intercompany transactions and balances have been eliminated. The Company consolidates entities the Company controls and records a noncontrolling interest for the portions not owned by the Company. Control is determined, where applicable, by the sufficiency of equity invested and the rights of the equity holders, and by the ownership of a majority of the voting interests, with consideration given to the existence of approval or veto rights granted to the minority stockholder. If the minority stockholder holds substantive participating rights, it overcomes the presumption of control by the majority voting interest holder. In contrast, if the minority stockholder simply holds protective rights (such as consent rights over certain actions), it does not overcome the presumption of control by the majority voting interest holder.
	Assets and liabilities of subsidiaries outside the United States with non-U.S. dollar functional currencies are translated into U.S. dollars using exchange rates as of the balance sheet dates. Income and expenses are translated using the average exchange rates for the reporting period. Foreign currency translation adjustments are recorded as a component of other comprehensive income. For the years ended December 31, 2013 and 2012, total revenues from properties outside the United States were $18.2 million and $10.3 million, respectively, which represented 2.9% and 2.0% of the Company's total revenues during the respective periods. The Company’s net investments in properties outside the United States were $190.2 million and $188.8 million at December 31, 2013 and December 31, 2012, respectively.
	Investments in Partnerships and Limited Liability Companies
	The Company evaluates its investments in limited liability companies and partnerships to determine whether such entities may be a VIE, and, if a VIE, whether the Company is the primary beneficiary. Generally, an entity is determined to be a VIE when either (1) the equity investors (if any) lack one or more of the essential characteristics of a controlling financial interest, (2) the equity investment at risk is insufficient to finance that entity's activities without additional subordinated financial support or (3) the equity investors have voting rights that are not proportionate to their economic interests and the activities of the entity involve or are conducted on behalf of an investor with a disproportionately small voting interest. The primary beneficiary is the entity that has both (1) the power to direct matters that most significantly impact the VIE's economic performance and (2) the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. The Company considers a variety of factors in identifying the entity that holds the power to direct matters that most significantly impact the VIE's economic performance including, but not limited to, the ability to direct financing, leasing, construction and other operating decisions and activities. In addition, the Company considers the rights of other investors to participate in policy making decisions, to replace or remove the manager and to liquidate or sell the entity. The obligation to absorb losses and the right to receive benefits when a reporting entity is affiliated with a VIE must be based on ownership, contractual, and/or other pecuniary interests in that VIE. The Company has determined that it is the primary beneficiary in five VIEs (excluding certain VIEs through its ownership of Wexford), consisting of single-tenant properties in which the tenant has a fixed-price purchase option, which are consolidated and reflected in the accompanying consolidated financial statements. Selected financial data of the VIEs at December 31, 2013 and December 31, 2012 consist of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Investment in real estate, net	$	336,832		$	334,331
	Total assets	375,443			369,460
	Total debt	143,067			144,889
	Total liabilities	154,953			149,336
	If the foregoing conditions do not apply, the Company considers whether a general partner or managing member controls a limited partnership or limited liability company. The general partner in a limited partnership or managing member in a limited liability company is presumed to control that limited partnership or limited liability company. The presumption may be overcome if the limited partners or members have either (1) the substantive ability to dissolve the limited partnership or limited liability company or otherwise remove the general partner or managing member without cause or (2) substantive participating rights, which provide the limited partners or members with the ability to effectively participate in significant decisions that would be expected to be made in the ordinary course of the limited partnership’s or limited liability company’s business and thereby preclude the general partner or managing member from exercising unilateral control over the partnership or company. If these criteria are met and the Company is the general partner or the managing member, as applicable, the consolidation of the partnership or limited liability company is required.
	Except for investments that are consolidated, the Company accounts for investments in entities over which it exercises significant influence, but does not control, under the equity method of accounting. These investments are recorded initially at cost and subsequently adjusted for equity in earnings and cash contributions and distributions. Under the equity method of accounting, the Company’s net equity in the investment is reflected in the consolidated balance sheets and its share of net income or loss is included in the Company’s consolidated statements of income.
	On a periodic basis, management assesses whether there are any indicators that the carrying value of the Company’s investments in unconsolidated partnerships or limited liability companies may be impaired on a more than temporary basis. An investment is impaired only if management’s estimate of the fair-value of the investment is less than the carrying value of the investment on a more than temporary basis. To the extent impairment has occurred, the loss is measured as the excess of the carrying value of the investment over the fair-value of the investment. Management does not believe that the carrying value of any of the Company’s unconsolidated investments in partnerships or limited liability companies was impaired as of December 31, 2013.
	The Company is also a party to certain VIEs through its ownership of Wexford, which are described in further detail in Note 11.
	Investments in Real Estate, Net
	Investments in real estate are carried at depreciated cost. Depreciation and amortization are recorded on a straight-line basis over the estimated useful lives of the assets as follows:
	Buildings and improvements	Remaining useful life, not to exceed 40 years
	Tenant improvements	Shorter of the useful lives or the terms of the related leases
	Furniture, fixtures, and equipment (other assets)	Three to five years
	Acquired in-place leases	Non-cancelable term of the related lease
	Acquired management agreements	Non-cancelable term of the related agreement
	Investments in real estate, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Land	$	713,955		$	702,993
	Land under development	119,325			48,744
	Buildings and improvements	4,854,175			4,028,089
	Construction in progress	316,025			143,340
		6,003,480			4,923,166
	Accumulated depreciation	(785,578		)	(603,450		)
		$	5,217,902		$	4,319,716
	Purchase accounting is applied to the assets and liabilities of real estate properties in which the Company acquires a controlling interest or a partial interest. The fair-value of tangible assets of an acquired property (which includes land, buildings, and improvements) is determined by valuing the property as if it were vacant, and the “as-if-vacant” value is then allocated to land, buildings and improvements based on management’s determination of the fair-value of these assets. Factors considered by the Company in performing these analyses include an estimate of the carrying costs during the expected lease-up periods, 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 rental revenue during the expected lease-up periods based on current market demand. Upon the acquisition of a controlling interest of an investment in an unconsolidated partnership, such partnership is consolidated and a gain is recognized equal to the amount in which the fair-value of the noncontrolling interest in such partnership exceeded its carrying value at the time of obtaining control.
	The aggregate value of other acquired intangible assets consisting of acquired in-place leases and acquired management agreements (see deferred leasing costs below) are recorded based on a variety of considerations including, but not necessarily limited to: (1) the value associated with avoiding the cost of originating the acquired in-place leases (i.e. the market cost to execute a lease, including leasing commissions and legal fees, if any); (2) the value associated with lost revenue related to tenant reimbursable operating costs estimated to be incurred during the assumed lease-up period (i.e. real estate taxes and insurance); and (3) the value associated with lost rental revenue from existing leases during the assumed lease-up period (see discussion of the recognition of acquired above-market and below-market leases in Revenue Recognition section below). The fair-value assigned to the acquired management agreements are recorded at the present value (using a discount rate which reflects the risks associated with the management agreements acquired) of the acquired management agreements with certain tenants of the acquired properties. The Company has also considered the existence of a tenant relationship intangible asset, but has not historically allocated any value to tenant relationships apart from acquired in-place leases. The values of in-place leases and management agreements are amortized to expense over the remaining non-cancelable period of the respective leases or agreements. If a lease were to be terminated or if termination is determined to be likely (e.g., in the case of a tenant bankruptcy) prior to its contractual expiration, amortization of all unamortized amounts related to that lease would be accelerated and such amounts written off.
	Costs incurred in connection with the development or construction of properties and improvements are capitalized. Capitalized costs include pre-construction costs essential to the development of the property, development costs, construction costs, interest costs, real estate taxes, salaries and related costs and other direct costs incurred during the period of development. The Company capitalizes costs on land and buildings under development until construction is substantially complete and the property is held available for occupancy. Determination of when a development project is substantially complete and when capitalization must cease involves a degree of judgment. The Company considers a construction project as substantially complete and held available for occupancy upon the completion of landlord-owned tenant improvements or when the lessee takes possession of the unimproved space for construction of its own improvements, but no later than one year from cessation of major construction activity. The Company ceases capitalization on the portion substantially completed and occupied or held available for occupancy, and capitalizes only those costs associated with any remaining portion under construction. Interest costs capitalized for the years ended December 31, 2013, 2012 and 2011 were $14.2 million, $8.6 million and $7.6 million, respectively. Payroll costs capitalized for the years ended December 31, 2013, 2012 and 2011 were $3.6 million, $2.0 million and $1.3 million, respectively. Costs associated with acquisitions of businesses are charged to expense.
	Repair and maintenance costs are charged to expense as incurred and significant replacements and betterments are capitalized. Repairs and maintenance costs include all costs that do not extend the useful life of an asset or increase its operating efficiency. Significant replacement and betterments represent costs that extend an asset’s useful life or increase its operating efficiency.
	Impairment of Long-Lived Assets and Long-Lived Assets to be Disposed
	The Company reviews long-lived assets and certain identifiable intangibles for impairment 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 its investments in long-lived assets. These assessments have a direct impact on the Company’s 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 to hold its properties over the long-term, 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, and such loss could be material.
	In April 2012, the Company completed the exchange of a property for another real estate operating property. As a result, the property disposed of was reclassified as a discontinued operation. This property was written down to its estimated fair-value of $28.0 million, less costs to sell, which resulted in an impairment loss of $4.6 million that is included in loss from discontinued operations for the year ended December 31, 2012. The parties to the exchange determined and agreed upon the fair-value of the property received in the transaction, which the Company considers to be a Level 2 input in the fair-value hierarchy. See Note 12 for discussion of discontinued operations.
	Cash and Cash Equivalents
	Cash and cash equivalents consist of highly liquid investments with original maturities of three months or less. The Company maintains its cash at insured financial institutions. The combined account balances at each institution periodically exceed FDIC insurance coverage, and, as a result, there is a concentration of credit risk related to amounts in excess of FDIC limits. The Company believes that the risk is not significant.
	Deferred Leasing Costs, Net
	Leasing commissions and other direct costs associated with obtaining new or renewal leases are recorded at cost and amortized on a straight-line basis over the terms of the respective leases, with remaining terms ranging from less than one year to approximately 20 years as of December 31, 2013. Deferred leasing costs also include the net carrying value of acquired in-place leases and acquired management agreements.
	Deferred leasing costs, net at December 31, 2013 consisted of the following (in thousands):
		Balance at			Accumulated
		December 31, 2013			Amortization				Net
	Acquired in-place leases	$	365,753		$	(233,935	)		$	131,818
	Acquired management agreements	25,801			(20,053		)		5,748
	Deferred leasing and other direct costs	91,142			(30,641		)		60,501
		$	482,696		$	(284,629	)		$	198,067
	Deferred leasing costs, net at December 31, 2012 consisted of the following (in thousands):
		Balance at			Accumulated
		31-Dec-12			Amortization				Net
	Acquired in-place leases	$	303,521		$	(185,463	)		$	118,058
	Acquired management agreements	24,963			(15,242		)		9,721
	Deferred leasing and other direct costs	68,175			(23,591		)		44,584
		$	396,659		$	(224,296	)		$	172,363
	The estimated amortization expense for deferred leasing costs at December 31, 2013 was as follows (in thousands):
	2014	$	40,251
	2015	31,707
	2016	25,031
	2017	22,959
2018	18,581
Thereafter	59,538
Total	$	198,067
Revenue Recognition, Operating Expenses and Lease Terminations
The Company commences revenue recognition on its leases based on a number of factors. In most cases, revenue recognition under a lease begins when the lessee takes possession of or controls the physical use of the leased asset. Generally, this occurs on the lease commencement date. In determining what constitutes the leased asset, the Company evaluates whether the Company or the lessee is the owner, for accounting purposes, of the tenant improvements. If the Company is the owner, for accounting purposes, of the tenant improvements, then the leased asset is the finished space and revenue recognition begins when the lessee takes possession of the finished space, typically when the improvements are substantially complete. If the Company concludes that it is not the owner, for accounting purposes, of the tenant improvements (the lessee is the owner), then the leased asset is the unimproved space and any tenant improvement allowances funded under the lease are treated as lease incentives, which reduce revenue recognized on a straight-line basis over the remaining non-cancelable term of the respective lease. In these circumstances, the Company begins revenue recognition when the lessee takes possession of the unimproved space for the lessee to construct improvements. The determination of who is the owner, for accounting purposes, of the tenant improvements determines the nature of the leased asset and when revenue recognition under a lease begins. The Company considers a number of different factors to evaluate whether it or the lessee is the owner of the tenant improvements for accounting purposes. These factors include:
•	whether the lease stipulates how and on what a tenant improvement allowance may be spent;
•	whether the tenant or landlord retain legal title to the improvements;
•	the uniqueness of the improvements;
•	the expected economic life of the tenant improvements relative to the length of the lease;
•	the responsible party for construction cost overruns; and
•	who constructs or directs the construction of the improvements.
The determination of who owns the tenant improvements, for accounting purposes, is subject to significant judgment. In making that determination, the Company considers all of the above factors. However, no one factor is determinative in reaching a conclusion.
All leases are classified as operating leases and minimum rents are recognized on a straight-line basis over the term of the related lease. The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in accrued straight-line rents on the accompanying consolidated balance sheets and contractually due but unpaid rents are included in accounts receivable. Existing leases at acquired properties are reviewed at the time of acquisition to determine if contractual rents are above or below current market rents for the acquired property. An identifiable lease intangible asset or liability is recorded based on the present value (using a discount rate that reflects the risks associated with the acquired leases) of the difference between (1) the contractual amounts to be paid pursuant to the in-place leases and (2) the Company’s estimate of the fair market lease rates for the corresponding in-place leases at acquisition, measured over a period equal to the remaining non-cancelable term of the leases and any fixed rate renewal periods (based on the Company’s assessment of the likelihood that the renewal periods will be exercised). The capitalized above-market lease values are amortized as a reduction of rental revenue on a straight-line basis over the remaining non-cancelable terms of the respective leases. The capitalized below-market lease values are amortized as an increase to rental revenue on a straight-line basis over the remaining non-cancelable terms of the respective leases and any fixed-rate renewal periods, if applicable. If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off.
The impact of the straight-line rent revenue, acquired above and below market lease revenue, and lease incentive revenue consisted of the following (in thousands):
	Years Ended December 31,
	2013			2012				2011
Straight-line rent revenue	$	23,136		$	23,288			$	25,243
Acquired above-market lease revenue	(11,913		)	(9,977		)		(9,607		)
Acquired below-market lease revenue	4,325			1,684				1,453
Lease incentive revenue	(2,295		)	(2,969		)		(2,246		)
Net increase in revenue	$	13,253		$	12,026			$	14,843
Total estimated minimum rents under non-cancelable operating tenant leases in effect at December 31, 2013 were as follows (in thousands):
2014	$	455,359
2015	450,564
2016	424,331
2017	400,787
2018	342,864
Thereafter	2,037,341
Total	$	4,111,246
The estimated amortization for acquired above- and below-market lease revenue and lease incentive revenue at December 31, 2013 was as follows (in thousands):
	2014			2015				2016				2017				2018				Thereafter			Total
Amortization of:
Acquired above-market leases	$	(4,457	)	$	(1,942	)		$	(1,317	)		$	(1,196	)		$	(1,112	)		$	(5,804	)	$	(15,828	)
Acquired below-market leases	5,262			3,721				3,487				3,435				3,427				18,789			38,121
Lease incentive	(2,232		)	(2,225		)		(2,152		)		(1,728		)		(1,329		)		(9,973		)	(19,639		)
Rental operations expenses, consisting of real estate taxes, insurance and common area maintenance costs, are subject to recovery from tenants under the terms of lease agreements. Amounts recovered are dependent on several factors, including occupancy and lease terms. Revenues are recognized in the period the expenses are incurred. The reimbursements are recorded in revenues as tenant recoveries, and the expenses are recorded in rental operations expenses, as the Company is generally the primary obligor with respect to purchasing goods and services from third-party suppliers, has discretion in selecting the supplier and bears the credit risk.
On an ongoing basis, the Company evaluates the recoverability of tenant balances, including rents receivable, straight-line rents receivable, tenant improvements, deferred leasing costs and any acquisition intangibles. Factors considered by the Company as part of this evaluation include, among other things, the financial strength of the tenant and any guarantors, a review of publicly filed documents and analyst research reports, a review of the tenant's cash balance and estimated cash "burn" rate if the tenant's cash flow from operations is negative, and the tenant's payment history. When it is determined that the recoverability of tenant balances is not probable, an allowance for expected losses related to tenant receivables, including straight-line rents receivable is recorded as a charge to earnings. Upon the termination of a lease, the amortization of tenant improvements, deferred leasing costs and acquisition intangible assets and liabilities is accelerated to the expected termination date as a charge to their respective line items and tenant receivables are written off as a reduction of the allowance in the period in which the balance is deemed to be no longer collectible. For financial reporting purposes, a lease is treated as terminated upon a tenant filing for bankruptcy, when a space is abandoned and a tenant ceases rent payments, or when other circumstances indicate that termination of a tenant’s lease is probable (e.g., eviction). Lease termination fees are recognized in other income when the related leases are canceled, the amounts to be received are fixed and determinable and collectability is assured, and when the Company has no continuing obligation to provide services to such former tenants.
Allowance for Doubtful Accounts
The Company maintains an allowance for doubtful accounts for estimated losses resulting from the inability of tenants to make required rent and tenant recovery payments or defaults. The Company maintains an allowance for accrued straight-line rents. The determination of this allowance is based on the tenants’ payment history and current credit status. Bad debt expense included in rental operations expenses was approximately $931,000, $1.7 million and $2.3 million for the years ended December 31, 2013, 2012 and 2011, respectively. The Company’s allowance for doubtful accounts included in accounts receivable, net and accrued straight line rent, net was approximately $2.3 million, $4.2 million and $2.9 million as of December 31, 2013, 2012 and 2011, respectively.
Investments
The Company, through its Operating Partnership, holds equity investments in certain publicly-traded companies and privately-held companies primarily involved in the life science industry. The Company may accept equity investments from tenants in lieu of cash rents, as prepaid rent pursuant to the execution of a lease, or as additional consideration for a lease termination. The Company does not acquire investments for trading purposes and, as a result, all of the Company’s investments in publicly-traded companies are considered “available-for-sale” and are recorded at fair-value. Changes in the fair-value of investments classified as available-for-sale are recorded in comprehensive income. The fair-value of the Company’s equity investments in publicly-traded companies is determined based upon the closing trading price of the equity security as of the balance sheet date, with unrealized gains and losses shown as a separate component of equity. Investments in privately-held companies are generally accounted for under the cost method, because the Company does not influence any operating or financial policies of the companies in which it invests. The classification of investments is determined at the time each investment is made, and such determination is reevaluated at each balance sheet date. The cost of investments sold is determined by the specific identification method, with net realized gains and losses included in other income. For all investments, if a decline in the fair-value of an investment below its carrying value is determined to be other-than-temporary, such investment is written down to its estimated fair-value with a non-cash charge to earnings. The factors that the Company considers in making these assessments include, but are not limited to, market prices, market conditions, available financing, prospects for favorable or unfavorable clinical trial results, new product initiatives and new collaborative agreements.
Investments in equity securities, which are included in other assets on the accompanying consolidated balance sheets, consisted of the following (in thousands):
	December 31,			December 31,
	2013			2012
Available-for-sale securities, historical cost	$	8,543		$	275
Unrealized gain, net	11,023			115
Available-for-sale securities, fair-value (1)	19,566			390
Privately-held securities, cost basis	18,485			12,280
Total equity securities	$	38,051		$	12,670
-1	Determination of fair-value is classified as Level 1 in the fair-value hierarchy based on the use of quoted prices in active markets.
The Company holds investments in available-for-sale securities of certain publicly-traded companies. Certain of these investments have fair-values less than the Company’s cost basis, net of previous other-than-temporary impairment in these securities due to decreases in their respective stock prices during the year ended December 31, 2013. However, management has the intent and ability to retain the investments for a period of time sufficient to allow for an anticipated recovery in their market value. Management will continue to periodically evaluate whether any investment, the fair-value of which is less than the Company’s cost basis, should be considered other-than-temporarily impaired. If other-than-temporary impairment is considered to exist, the related unrealized loss will be reclassified from accumulated other comprehensive loss and recorded as a reduction of net income.
The Company also holds investments in securities of certain privately-held companies and funds, which are recorded at cost basis due to the Company’s lack of control or significant influence over such companies and funds.
During the year ended December 31, 2013, the Company recorded a $2.8 million impairment charge, which is included in other expense in the consolidated statements of operations. The impairment charge related to the Company’s investment in a privately-held company, comprising a $2.0 million cost basis equity investment and $825,000 related to notes receivable that were included in other assets on the consolidated balance sheets. Other than this investment there were no identified events or changes in circumstances that may have a significant adverse effect on the carrying value of the Company’s cost basis investments and therefore, no evaluation of impairment was performed during the year ended December 31, 2013 on the Company’s remaining cost basis investments.
Share-Based Payments
All share-based payments to employees are recognized in the consolidated statement of operations based on their fair-value. Through December 31, 2013, the Company had awarded restricted stock of the Parent Company and LTIP unit grants of the Operating Partnership under its incentive award plan, both of which are valued based on the closing market price of the underlying common stock on the date of grant, and had not granted any stock options. During the years ended December 31, 2013 and 2012, the Parent Company awarded performance units (the “Performance Units”) to certain of its executive officers. Each Performance Unit represents a contingent right to receive one share of the Parent Company’s common stock if vesting conditions are satisfied. The grant date fair-value of the Performance Units was estimated using a Monte Carlo simulation which considered the likelihood of achieving the vesting conditions (see Note 13 for further information on the fair-value of the Performance Units). The fair-value of all share-based payments is amortized to general and administrative expense and rental operations expense over the relevant service period, adjusted for anticipated forfeitures.
Assets and Liabilities Measured at Fair-Value
The Company measures financial instruments and other items at fair-value where required under GAAP, but has elected not to measure any additional financial instruments and other items at fair-value as permitted under fair-value option accounting guidance.
Fair-value measurement is determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair-value measurements, there is a fair-value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy).
Level 1 inputs utilize 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. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. 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 Company has used interest rate swaps to manage its interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. The fair-values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair-value measurements. In adjusting the fair-value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees.
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. However, as of December 31, 2013, the Company has determined that the impact of the credit valuation adjustments on the overall valuation of its derivative positions is not significant. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair-value hierarchy (see Note 9).
The valuation of the Company’s investments in publicly-traded companies utilizes observable market-based inputs, based on the closing trading price of securities as of the balance sheet date, therefore, the Company has determined that valuations of available-for-sale securities are classified in Level 1 of the fair-value hierarchy.
No other assets or liabilities are measured at fair-value on a recurring basis, or have been measured at fair-value on a non-recurring basis subsequent to initial recognition, in the accompanying consolidated balance sheets as of December 31, 2013 and 2012.
Derivative Instruments
The Company records all derivatives on the consolidated balance sheets at fair-value. In determining the fair-value of its derivatives, the Company considers the credit risk of its counterparties and the Company. These counterparties are generally larger financial institutions engaged in providing a variety of financial services. These institutions generally face similar risks regarding adverse changes in market and economic conditions, including, but not limited to, fluctuations in interest rates, exchange rates, equity and commodity prices and credit spreads. The ongoing disruptions in the financial markets have heightened the risks to these institutions. While management believes that its counterparties will meet their obligations under the derivative contracts, it is possible that defaults may occur.
The accounting for changes in the fair-value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair-value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair-value hedges. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Derivatives may also be designated as hedges of the foreign currency exposure of a net investment in a foreign operation. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair-value of the hedged asset or liability that are attributable to the hedged risk in a fair-value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risks, even though hedge accounting does not apply or the Company elects not to apply hedge accounting.
For derivatives designated as cash flow hedges, the effective portion of changes in the fair-value of the derivative is initially reported in other comprehensive income (outside of earnings) and subsequently reclassified to earnings in the period in which the hedged transaction affects earnings. If charges relating to the hedged transaction are being deferred pursuant to redevelopment or development activities, the effective portion of changes in the fair-value of the derivative are also deferred in accumulated other comprehensive income on the consolidated balance sheet, and are amortized to the income statement once the deferred charges from the hedged transaction begin again to affect earnings. The ineffective portion of changes in the fair-value of the derivative is recognized directly in earnings. The Company assesses the effectiveness of each hedging relationship by comparing the changes in cash flows of the derivative hedging instrument with the changes in cash flows of the designated hedged item or transaction. For derivatives that are not classified as hedges, changes in the fair-value of the derivative are recognized directly in earnings in the period in which the change occurs.
The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its debt funding and the use of derivative financial instruments. Specifically, the Company enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known or expected cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings.
The Company’s primary objective in using derivatives is to add stability to interest expense and to manage its exposure to interest rate movements or other identified risks. To accomplish this objective, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying principal amount. During the years ended December 31, 2013, 2012 and 2011, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt and future variability in the interest-related cash flows from forecasted issuances of debt (see Note 9). The Company formally documents the hedging relationships for all derivative instruments, has historically accounted for its interest rate swap agreements as cash flow hedges, and does not use derivatives for trading or speculative purposes.
Equity Offering Costs
Underwriting commissions and offering costs are reflected as a reduction of proceeds.
Income Taxes of the Parent Company
The Parent Company has elected to be taxed as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. The Parent Company believes it has qualified and continues to qualify as a REIT. A REIT is generally not subject to federal income tax on that portion of its taxable income that is distributed to its stockholders. Accordingly, no provision has been made for federal income taxes in the accompanying consolidated financial statements. REITs are subject to a number of organizational and operational requirements. If the Parent Company fails to qualify as a REIT in any taxable year, the Parent Company will be subject to federal income tax (including any applicable alternative minimum tax) and, in most of the states, state income tax on its taxable income at regular corporate tax rates. The Parent Company is subject to certain state and local taxes.
Income Taxes of the Operating Partnership
As a partnership, the allocated share of income of the Operating Partnership is included in the income tax returns of the general and limited partners. Accordingly, no accounting for income taxes is required in the accompanying consolidated financial statements. The Operating Partnership may be subject to certain state or local taxes on its income and property.
The Operating Partnership has formed certain taxable REIT subsidiaries (each a “TRS”) on behalf of the Parent Company. In general, each TRS may perform non-customary services for tenants, hold assets that the Parent Company cannot hold directly and, except for the operation or management of health care facilities or lodging facilities or the providing of any person, under a franchise, license or otherwise, rights to any brand name under which any lodging facility or health care facility is operated, may engage in any real estate or non-real estate related business. Each TRS is subject to corporate federal and state income taxes on its taxable income at regular corporate tax rates. There is no tax provision for any TRS for the periods presented in the accompanying consolidated statements of income due to net operating losses incurred. No tax benefits have been recorded since it is not considered more likely than not that the deferred tax asset related to the net operating loss carryforwards will be utilized.
Dividends and Distributions
Earnings and profits, which determine the taxability of dividends and distributions to stockholders, will differ from income reported for financial reporting purposes due to the difference for federal income tax purposes in the treatment of revenue recognition, compensation expense, and in the estimated useful lives of real estate assets used to compute depreciation.
The income tax treatment for dividends was as follows:
	For the Years Ended December 31,
	2013						2012							2011
	Per Share			%			Per Share				%			Per Share				%
Common stock:
Ordinary income	$	0.94		100	%		$	0.63			74.12	%		$	0.44			57.14	%
Capital gain	—			—			—				—			—				—
Return of capital	—			—			0.22				25.88	%		0.33				42.86	%
Total	$	0.94		100	%		$	0.85			100	%		$	0.77			100	%
Preferred stock:
Ordinary income	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%
Capital gain	—			—			—				—			—				—
Return of capital	—			—			—				—			—				—
Total	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%
Construction Loan Receivable
The Company has a $255.0 million interest in a $355.0 million construction loan secured by first priority mortgages on a 1.1 million square foot laboratory, office and retail development project located in Boston, Massachusetts, which is 95% leased to Vertex Pharmaceuticals Incorporated to serve as its new corporate headquarters.
The construction loan matures on September 30, 2014, with two one -year extension options exercisable at the borrower’s election after paying the lenders an extension fee on the then-outstanding principal amount. The construction loan bears interest on the outstanding principal amount at a floating rate equal to the greater of (1) reserve adjusted LIBOR plus 550 basis points and (2) 6.5%. In addition, the borrower is required to pay a fee to the lenders based on a specified percentage of the average daily unfunded amount of the construction loan. The borrower may prepay the construction loan in part under certain circumstances, and may prepay the construction loan in full with prior notice and a prepayment fee to the lenders. As of December 31, 2013 and December 31, 2012, the Company had invested approximately $151.8 million and $21.7 million in the construction loan, respectively, which are included in other assets on the Company's consolidated balance sheet. The Company expects to have fully funded its obligation in the third quarter of 2014.
Lease Termination
During the years ended December 31, 2013, 2012 and 2011, the Company recorded lease termination revenue, net of write-offs of lease intangibles, included in other revenue on the consolidated statement of operations of approximately $42.8 million, $3.5 million and $6.2 million, respectively. Lease termination revenue for the year ended December 31, 2013 related to the termination of a lease with Elan Corporation (“Elan”) at the Company’s Science Center at Oyster Point property for which Elan paid the Company $46.5 million, and the termination of a lease effective August 2013 with Merck at the Company's 320 Bent Street property for which Merck paid the Company $8.7 million in August 2012. Lease termination revenue for the year ended December 31, 2012 primarily related to the termination of the lease with Merck. Lease termination revenue for the year ended December 31, 2011 related to an early lease termination at one of our properties.
Management’s Estimates
Management has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reporting of revenue and expenses during the reporting period to prepare these consolidated financial statements in conformity with GAAP. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and reported amounts of revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates under different assumptions or conditions.

Equity_of_the_Parent_Company

Equity of the Parent Company	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Equity of the Parent Company	'
	Equity of the Parent Company
	During the year ended December 31, 2013, the Parent Company issued restricted stock awards to the Company’s employees and directors totaling 625,840 and 31,266 shares of common stock, respectively (253,671 shares of common stock were surrendered to the Company and subsequently retired in lieu of cash payments for taxes due on the vesting of restricted stock and 39,805 shares were forfeited during the same period), which are included in the total of common stock outstanding as of the period end.
	Of the restricted stock awards issued to the Company's employees, 20,069 shares were issued as part of the consideration paid in the Company's merger with Wexford (as discussed below), and 41,568 shares are subject to performance-based vesting conditions. In addition, in connection with the merger with Wexford, the Operating Partnership issued 132,441 operating partnership units which are also subject to performance-based vesting conditions. The aggregate grant date fair-value of these performance-based awards of approximately $3.6 million will be recognized as compensation expense on a straight-line basis over each respective vesting period. The total compensation expense remaining for these awards to be expensed in future periods as of December 31, 2013 was approximately $3.2 million over a weighted-average term of approximately 3.40 years. Dividends and distributions are payable on these awards from the date of issuance.
	The Parent Company awarded units to certain of its executive officers (the “Performance Units”), which represent a contingent right to receive one share of the Parent Company’s common stock if vesting conditions are satisfied. Outstanding Performance Units vest ratably over two or three year periods (each, a “Performance Period”) based upon the Parent Company’s total stockholder return relative to its peer group (the "Market Conditions"). The grant date fair-value of the Performance Units was estimated using a Monte Carlo simulation which considered the likelihood of achieving the Market Conditions. The expected value of the Performance Units on the grant date was determined by simulating the total stockholder return for the Parent Company and the peer group, considering the stock price variance for each of the peer group companies compared to each other and the Parent Company. In January 2013, 136,296 Performance Units, which were originally granted to certain executive officers in January 2012 and represent the maximum number of Performance Units that could have vested, were forfeited as a result of the Parent Company's total stockholder return relative to its peer group in 2012 being below the threshold for any payout. In January 2014, of the 136,296 Performance Units which were originally granted to certain executive officers in January 2012 and represent the maximum number of Performance Units that could have vested, 20,224 Performance Units vested (resulting in the issuance of 20,224 shares of the Parent Company’s common stock) and the remaining 116,072 Performance Units were forfeited, based on the Parent Company’s total stockholder return relative to its peer group for the two years ending December 31, 2013. During the year ended December 31, 2013, the Parent Company awarded 406,288 performance units which represent the maximum number of Performance Units that may vest. The grant date fair-value of these awards of approximately $3.6 million will be recognized as compensation expense on a straight-line basis over each respective Performance Period. The total compensation remaining on the Performance Units granted during the year ended December 31, 2013 to be expensed in future periods over a weighted-average term of approximately 1.56 years was $2.1 million as of December 31, 2013. No dividends will be paid or accrued on the Performance Units, and shares of the Parent Company's common stock will not be issued until vesting of the Performance Units occurs.
	In February 2013, the Parent Company issued 14,605,000 shares of common stock and contributed net proceeds of approximately $287.0 million, after deducting the underwriters' discounts and commissions and offering expenses, to the Operating Partnership in exchange for the issuance of 14,605,000 operating partnership units. The net proceeds to the Operating Partnership were utilized to fund the acquisition of the Woodside Technology Park property in Redwood City, California, to fund a portion of the redemption of all 7,920,000 outstanding shares of the Parent Company's 7.375% Series A Cumulative Redeemable Preferred Stock (“Series A preferred stock”), to repay a portion of the outstanding indebtedness under its unsecured line of credit and for other general corporate and working capital purposes.
	In April 2013, the Parent Company issued 17,250,000 shares of common stock and contributed net proceeds of approximately $354.1 million, after deducting the underwriters' discounts and commissions and offering expenses, to the Operating Partnership in exchange for the issuance of 17,250,000 operating partnership units. The net proceeds to the Operating Partnership were utilized to repay a portion of the outstanding indebtedness under its unsecured line of credit, to fund a portion of the purchase price of the merger with Wexford and for other general corporate and working capital purposes.
	In May 2013, as part of the consideration paid for the merger with Wexford, the sellers received 5,568,227 shares of the Parent Company’s common stock and 336,960 operating partnership units, of which 20,069 shares of common stock and all of the operating partnership units are subject to certain restrictions.
	In June 2013, as part of the consideration paid for the Company’s acquisition of the 320 Charles Street property in Cambridge, Massachusetts, the seller received 2,034,211 operating partnership units.
	Common Stock, Operating Partnership Units and LTIP Units
	As of December 31, 2013, the Company had outstanding 192,115,002 shares of the Parent Company’s common stock and 5,083,400 and 332,574 operating partnership and LTIP units, respectively (excluding operating partnership units held by the Parent Company). A share of the Parent Company’s common stock and the operating partnership and LTIP units have essentially the same economic characteristics as they share equally in the total net income or loss and distributions of the Operating Partnership.
	7.375% Series A Cumulative Redeemable Preferred Stock
	On March 15, 2013, the Parent Company redeemed all 7,920,000 outstanding shares of its Series A preferred stock for approximately $198.0 million, or $25.00 per share, net of accrued dividends of approximately $2.4 million, or $0.30217 per share. The redemption of the Series A preferred stock resulted in the recognition of costs on redemption of preferred stock of approximately $6.5 million for the year ended December 31, 2013 as a result of the difference between the carrying value and the price paid to redeem the Series A preferred stock.
	Dividends and Distributions
	The following table lists the dividends and distributions declared by the Parent Company and the Operating Partnership during the year ended December 31, 2013:
	Declaration Date		Securities Class		Amount Per				Period Covered		Dividend and		Dividend and
					Share/Unit						Distribution		Distribution Amount
											Payable Date
													(In thousands)
	March 15, 2013		Common stock and OP units		$	0.235			January 1, 2013 to March 31, 2013		April 15, 2013		$	40,413
	June 14, 2013		Common stock and OP units		$	0.235			April 1, 2013 to June 30, 2013		July 15, 2013		$	46,381
	September 16, 2013		Common stock and OP units		$	0.235			July 1, 2013 to September 30, 2013		October 15, 2013		$	46,418
	December 12, 2013		Common stock and OP units		$	0.25			October 1, 2013 to December 31, 2013		January 15, 2014		$	49,383
	Total 2013 dividends and distributions declared through December 31, 2013 (in thousands):
	Common stock and OP units	$	182,595
	Series A preferred stock/units (1)	2,393
		$	184,988
	-1	On March 15, 2013, the Parent Company redeemed all 7,920,000 outstanding shares of its Series A preferred stock for approximately $198.0 million, or $25.00 per share, net of accrued dividends of approximately $2.4 million, or $0.30217 per share.
	Changes in Accumulated Other Comprehensive Loss by Component
		Foreign currency translation adjustments				Unrealized gains on available-for-sale securities				Gain / (loss) on derivative instruments				Total
	Balance at December 31, 2012	$	3,543			$	114			$	(58,382	)		$	(54,725	)
	Other comprehensive income before reclassifications	395				9,071				3,497				12,963
	Amounts reclassified from accumulated other comprehensive income (1)	—				1,836				9,451				11,287
	Net other comprehensive income	395				10,907				12,948				24,250
	Net other comprehensive income allocable to noncontrolling interests	(33		)		(2,083		)		(332		)		(2,448		)
	Balance as of December 31, 2013	$	3,905			$	8,938			$	(45,766	)		$	(32,923	)
	-1	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.
	Noncontrolling Interests
	Noncontrolling interests on the consolidated balance sheets of the Parent Company relate primarily to the OP units in the Operating Partnership that are not owned by the Parent Company. With respect to the noncontrolling interests in the Operating Partnership, noncontrolling interests with redemption provisions that permit the issuer to settle in either cash or common stock at the option of the issuer are further evaluated to determine whether temporary or permanent equity classification on the balance sheet is appropriate. Because the OP units comprising the noncontrolling interests contain such a provision, the Company evaluated this guidance, including the requirement to settle in unregistered shares, and determined that the OP units meet the requirements to qualify for presentation as permanent equity.
	The Company evaluates individual redeemable noncontrolling interests for the ability to continue to recognize the noncontrolling interest as permanent equity in the consolidated balance sheets. Any redeemable noncontrolling interest that fails to qualify as permanent equity will be reclassified as temporary equity and adjusted to the greater of (1) the carrying amount, or (2) its redemption value at the end of the period in which the determination is made.
	The redemption value of the OP units not owned by the Parent Company, had such units been redeemed at December 31, 2013, was approximately $99.4 million based on the average closing price of the Parent Company’s common stock of $18.35 per share for the ten consecutive trading days immediately preceding December 31, 2013.
	The following table shows the vested ownership interests in the Operating Partnership:
		December 31, 2013						December 31, 2012
		Operating Partnership Units and LTIP Units			Percentage of Total			Operating Partnership Units and LTIP Units			Percentage of Total
	BioMed Realty Trust	190,676,428			97.3	%		152,853,368			98.1	%
	Noncontrolling interest consisting of:
	Operating partnership and LTIP units held by employees and related parties	2,656,388			1.4	%		2,339,314			1.5	%
	Operating partnership and LTIP units held by third parties	2,627,145			1.3	%		565,051			0.4	%
	Total	195,959,961			100	%		155,757,733			100	%

Capital_of_the_Operating_Partn

Capital of the Operating Partnership	12 Months Ended
	Dec. 31, 2013
Partners' Capital [Abstract]	'
Capital of the Operating Partnership	'
	Capital of the Operating Partnership
	Operating Partnership Units and LTIP Units
	As of December 31, 2013, the Operating Partnership had outstanding 197,198,402 operating partnership units and 332,574 LTIP units. The Parent Company owned 97.3% of the partnership interests in the Operating Partnership at December 31, 2013, is the Operating Partnership’s general partner and is responsible for the management of the Operating Partnership’s business. As the general partner of the Operating Partnership, the Parent Company effectively controls the ability to issue common stock of the Parent Company upon a limited partner’s notice of redemption. In addition, the Parent Company has generally acquired OP units upon a limited partner’s notice of redemption in exchange for shares of its common stock. The redemption provisions of OP units owned by limited partners that permit the Parent Company to settle in either cash or common stock at the option of the Parent Company are further evaluated in accordance with applicable accounting guidance to determine whether temporary or permanent equity classification on the balance sheet is appropriate. The Operating Partnership evaluated this guidance, including the requirement to settle in unregistered shares, and determined that these OP units meet the requirements to qualify for presentation as permanent equity.
	LTIP units represent a profits interest in the Operating Partnership for services rendered or to be rendered by the LTIP unit holder in its capacity as a partner, or in anticipation of becoming a partner, in the Operating Partnership. Upon the occurrence of specified events, LTIP units may over time achieve full parity with common units of the Operating Partnership for all purposes. Upon achieving full parity, LTIP units may be redeemed for an equal number of the Parent Company’s common stock or cash, at the Parent Company’s election.
	The redemption value of the OP units owned by the limited partners, not including the Parent Company, had such units been redeemed at December 31, 2013, was approximately $99.4 million based on the average closing price of the Parent Company’s common stock of $18.35 per share for the ten consecutive trading days immediately preceding December 31, 2013.
	Changes in Accumulated Other Comprehensive Loss by Component
		Foreign currency translation adjustments		Unrealized gains on available- for-sale securities			Gain / (loss) on derivative instruments			Total
	Balance at December 31, 2012	$	3,611	$	115		$	(56,803	)	$	(53,077	)
	Other comprehensive income before reclassifications	395		9,071			3,497			12,963
	Amounts reclassified from accumulated other comprehensive income (1)	—		1,836			9,451			11,287
	Net other comprehensive income	395		10,907			12,948			24,250
	Net other comprehensive income allocable to noncontrolling interest	$	—	$	(1,836	)	$	—		$	(1,836	)
	Balance as of December 31, 2013	$	4,006	$	9,186		$	(43,855	)	$	(30,663	)
	-1	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.

Debt

Debt	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Debt Disclosure	'
	Debt
	Debt of the Parent Company
	The Parent Company does not hold any indebtedness. All debt is held directly or indirectly by the Operating Partnership; however, the Parent Company has guaranteed the Operating Partnership’s mortgage loan secured by the Company’s Center for Life Science | Boston property, Exchangeable Senior Notes due 2030 (the “Exchangeable Senior Notes”), Unsecured Senior Notes due 2016 (the “Notes due 2016”), Unsecured Senior Notes due 2020 (the “Notes due 2020”), Unsecured Senior Notes due 2022 (the “Notes due 2022”), Unsecured Senior Term Loan due 2017 (the “Term Loan due 2017”), Unsecured Senior Term Loan due 2018 (the “Term Loan due 2018”) and unsecured line of credit.
	Debt of the Operating Partnership
	The following is a summary of the Operating Partnership’s outstanding consolidated debt as of December 31, 2013 and December 31, 2012 (dollars in thousands):
		Stated Interest Rate		Effective Interest Rate		Principal Balance
						December 31,			December 31,			Maturity Date
						2013			2012
	Mortgage Notes Payable
	9900 Belward Campus Drive	5.64	%	3.99	%	$	10,631		$	10,767		July 1, 2017
	9901 Belward Campus Drive	5.64	%	3.99	%	13,091			13,260			July 1, 2017
	Center for Life Science | Boston	7.75	%	7.75	%	334,447			338,447			June 30, 2014
	4320 Forest Park Avenue (1)	4	%	2.7	%	21,000			—			June 30, 2015
	Hershey Center for Applied Research (1)	6.15	%	4.71	%	13,449			—			May 5, 2027
	500 Kendall Street (Kendall D)	6.38	%	5.45	%	57,927			60,164			December 1, 2018
	Shady Grove Road	5.97	%	5.97	%	143,067			144,889			September 1, 2016
	University of Maryland BioPark I (1)	5.93	%	4.69	%	16,752			—			May 15, 2025
	University of Maryland BioPark II (1)	5.2	%	4.33	%	62,946			—			September 5, 2021
	University of Maryland BioPark Garage (1)	5.2	%	4.33	%	4,738			—			September 1, 2021
	University of Miami Life Science & Technology Park (1)	4	%	2.89	%	20,000			—			February 1, 2016
						698,048			567,527
	Unamortized premiums					11,276			4,125
	Mortgage notes payable, net					709,324			571,652
	Exchangeable Senior Notes	3.75	%	3.75	%	180,000			180,000			January 15, 2030
	Notes due 2016	3.85	%	3.99	%	400,000			400,000			April 15, 2016
	Notes due 2020	6.13	%	6.27	%	250,000			250,000			April 15, 2020
	Notes due 2022	4.25	%	4.36	%	250,000			250,000			July 15, 2022
						900,000			900,000
	Unamortized discounts					(4,917		)	(5,823		)
	Unsecured senior notes, net					895,083			894,177
	Term Loan due 2017 - U.S. dollar (2)	1.82	%	2.63	%	243,596			243,596			March 30, 2017
	Term Loan due 2017 - GBP (2)	2.14	%	2.39	%	165,190			161,860			March 30, 2017
	Term Loan due 2018 (3)	1.67	%	1.97	%	350,000			—			March 24, 2018
	Unsecured senior term loans					758,786			405,456
	Unsecured line of credit (3) (4)	1.46	%	1.46	%	128,000			118,000			March 24, 2018
	Total consolidated debt					$	2,671,193		$	2,169,285
	-1	Mortgage notes which were assumed on May 31, 2013 in connection with the Company’s merger with Wexford.
	-2	In August 2012, the Operating Partnership converted approximately $156.4 million of outstanding borrowings into British pounds sterling (“GBP”) equal to £100.0 million, which was designated as a net investment hedge to mitigate the risk of fluctuations in foreign currency exchange rates. The principal balance represents the U.S. dollar amount based on the exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively. The effective interest rate includes the impact of interest rate swap agreements (see Note 9 for further discussion of interest rate swap agreements).
	-3	In September 2013, the Operating Partnership amended and restated its unsecured credit agreement, providing for aggregate borrowing of up to $1.25 billion, consisting of an unsecured line of credit of $900.0 million and a term loan of $350.0 million (the Term Loan due 2018). In connection with the amendment and restatement of the credit agreement, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.
	-4	At December 31, 2013, the Operating Partnership had additional borrowing capacity under the unsecured line of credit of up to approximately $772.0 million.
	Mortgage Notes Payable, net
	The net carrying value of properties (investments in real estate) secured by the Operating Partnership’s mortgage notes payable was approximately $1.2 billion and $1.0 billion at December 31, 2013 and 2012, respectively.
	The Operating Partnership’s $334.4 million mortgage loan, which is secured by the Company’s Center for Life Science | Boston property in Boston, Massachusetts, includes a financial covenant relating to a minimum amount of net worth. Management believes that the Operating Partnership was in compliance with this covenant as of December 31, 2013. Notwithstanding the financial covenant related to the Center for Life Science | Boston mortgage, no other financial covenants are required on the remaining mortgage notes payable.
	Premiums were recorded upon assumption of the mortgage notes payable at the time of the related property acquisition to account for above-market interest rates. Amortization of these premiums is recorded as a reduction to interest expense over the remaining term of the respective note using a method that approximates the effective-interest method.
	Exchangeable Senior Notes
	On January 11, 2010, the Operating Partnership issued $180.0 million aggregate principal amount of its Exchangeable Senior Notes. The Exchangeable Senior Notes are general senior unsecured obligations of the Operating Partnership and rank equally in right of payment with all other senior unsecured indebtedness of the Operating Partnership. Interest at a rate of 3.75% per annum is payable on January 15 and July 15 of each year, beginning on July 15, 2010, until the stated maturity date of January 15, 2030. The terms of the Exchangeable Senior Notes are governed by an indenture, dated January 11, 2010, among the Operating Partnership, as issuer, the Parent Company, as guarantor, and U.S. Bank National Association, as trustee. The Exchangeable Senior Notes contain an exchange settlement feature, which provides that the Exchangeable Senior Notes may, at any time prior to the close of business on the second scheduled trading day preceding the maturity date, be exchangeable for shares of the Parent Company’s common stock at the then applicable exchange rate. As the exchange feature for the Exchangeable Senior Notes must be settled in the common stock of the Parent Company, accounting guidance applicable to convertible debt instruments that permit the issuer to settle all or a portion of the exchange feature in cash upon conversion does not apply. The initial exchange rate was 55.0782 shares per $1,000 principal amount of Exchangeable Senior Notes, representing an exchange price of approximately $18.16 per share of the Parent Company’s common stock. If certain designated events occur on or prior to January 15, 2015 and a holder elects to exchange Exchangeable Senior Notes in connection with any such transaction, the Company will increase the exchange rate by a number of additional shares of the Parent Company’s common stock based on the date the transaction becomes effective and the price paid per share of the Parent Company’s common stock in the transaction, as set forth in the indenture governing the Exchangeable Senior Notes. The exchange rate for the Exchangeable Senior Notes may be adjusted under certain circumstances, including the payment of cash dividends in excess of $0.14 per share of common stock. The increase in the quarterly cash dividend through 2013 resulted in an increase in the exchange rate of the Exchangeable Senior Notes to 57.8068 shares per $1,000 principal amount of Exchangeable Senior Notes (a conversion value of $17.30 per share), effective as of September 26, 2013, the Company’s ex-dividend date for the third quarter 2013 dividend.
	The Operating Partnership may redeem the Exchangeable Senior Notes, in whole or in part, at any time to preserve the Parent Company’s status as a REIT or at any time on or after January 21, 2015 for cash at 100% of the principal amount plus accrued and unpaid interest. The holders of the Exchangeable Senior Notes have the right to require the Operating Partnership to repurchase the Exchangeable Senior Notes, in whole or in part, for cash on each of January 15, 2015, January 15, 2020 and January 15, 2025, or upon the occurrence of a designated event, in each case for a repurchase price equal to 100% of the principal amount of the Exchangeable Senior Notes plus accrued and unpaid interest. The terms of the indenture for the Exchangeable Senior Notes do not require compliance with any financial covenants.
	Unsecured Senior Notes due 2016, net
	On March 30, 2011, the Operating Partnership issued $400.0 million aggregate principal amount of its Notes due 2016. The purchase price paid by the underwriters was 99.365% of the principal amount and the Notes due 2016 have been recorded on the consolidated balance sheet net of the discount. The Notes due 2016 are senior unsecured obligations of the Operating Partnership and rank equally in right of payment with all other senior unsecured indebtedness of the Operating Partnership. However, the Notes due 2016 are effectively subordinated to the Operating Partnership’s existing and future mortgages and other secured indebtedness (to the extent of the value of the collateral securing such indebtedness) and to all existing and future preferred equity and liabilities, whether secured or unsecured, of the Operating Partnership’s subsidiaries, including guarantees provided by the Operating Partnership’s subsidiaries under the Operating Partnership’s unsecured line of credit. Interest at a rate of 3.85% per year is payable on April 15 and October 15 of each year, beginning on October 15, 2011, until the stated maturity date of April 15, 2016. The terms of the Notes due 2016 are governed by a base indenture and supplemental indenture, each dated March 30, 2011, among the Operating Partnership, as issuer, the Parent Company, as guarantor, and U.S. Bank National Association, as trustee.
	The Operating Partnership may redeem the Notes due 2016, in whole or in part, at any time for cash at a redemption price equal to the greater of (1) 100% of the principal amount of the Notes due 2016 being redeemed; or (2) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date on a semi-annual basis at the adjusted treasury rate plus 30 basis points, plus in each case, accrued and unpaid interest.
	The terms of the indenture for the Notes due 2016 require compliance with various financial covenants, including limits on the amount of total leverage and secured debt maintained by the Operating Partnership and which require the Operating Partnership to maintain minimum levels of debt service coverage. Management believes that it was in compliance with these covenants as of December 31, 2013.
	Unsecured Senior Notes due 2020, net
	On April 29, 2010, the Operating Partnership issued $250.0 million aggregate principal amount of its Notes due 2020. The purchase price paid by the initial purchasers was 98.977% of the principal amount and the Notes due 2020 have been recorded on the consolidated balance sheet net of the discount. The Notes due 2020 are senior unsecured obligations of the Operating Partnership and rank equally in right of payment with all other senior unsecured indebtedness of the Operating Partnership. However, the Notes due 2020 are effectively subordinated to the Operating Partnership’s existing and future mortgages and other secured indebtedness (to the extent of the value of the collateral securing such indebtedness) and to all existing and future preferred equity and liabilities, whether secured or unsecured, of the Operating Partnership’s subsidiaries, including guarantees provided by the Operating Partnership’s subsidiaries under the Company’s unsecured line of credit. Interest at a rate of 6.125% per year is payable on April 15 and October 15 of each year, beginning on October 15, 2010, until the stated maturity date of April 15, 2020. The terms of the Notes due 2020 are governed by an indenture, dated April 29, 2010, among the Operating Partnership, as issuer, the Parent Company, as guarantor, and U.S. Bank National Association, as trustee.
	The Operating Partnership may redeem the Notes due 2020, in whole or in part, at any time for cash at a redemption price equal to the greater of (1) 100% of the principal amount of the Notes due 2020 being redeemed; or (2) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date on a semi-annual basis at the adjusted treasury rate plus 40 basis points, plus in each case, accrued and unpaid interest.
	The terms of the indenture for the Notes due 2020 require compliance with various financial covenants, including limits on the amount of total leverage and secured debt maintained by the Operating Partnership and which require the Operating Partnership to maintain minimum levels of debt service coverage. Management believes that it was in compliance with these covenants as of December 31, 2013.
	On January 12, 2011, in accordance with the registration rights agreement entered into among the Company, the Operating Partnership and the initial purchasers of the Notes due 2020, the Operating Partnership completed its exchange offer to exchange all of the outstanding unregistered Notes due 2020 for an equal principal amount of a new issue of 6.125% Senior Notes due 2020 pursuant to an effective registration statement on Form S-4 filed with the Securities and Exchange Commission. A total of $250.0 million aggregate principal amount of the original Notes due 2020, representing 100% of the outstanding principal amount of the original Notes due 2020, was tendered and received prior to the expiration of the exchange offer. The terms of the Notes due 2020 are substantially identical to the original Notes due 2020, except for transfer restrictions and registration rights relating to the original Notes due 2020.
	Unsecured Senior Notes due 2022, net
	On June 28, 2012, the Operating Partnership issued $250.0 million aggregate principal amount of its Notes due 2022. The purchase price paid by the underwriters was 99.126% of the principal amount and the Notes due 2022 have been recorded on the consolidated balance sheet net of the discount. The Notes due 2022 are senior unsecured obligations of the Operating Partnership and rank equally in right of payment with all other senior unsecured indebtedness of the Operating Partnership. However, the Notes due 2022 are effectively subordinated to the Operating Partnership’s existing and future mortgages and other secured indebtedness (to the extent of the value of the collateral securing such indebtedness) and to all existing and future preferred equity and liabilities, whether secured or unsecured, of the Operating Partnership’s subsidiaries, including guarantees provided by the Operating Partnership’s subsidiaries under the Operating Partnership’s unsecured line of credit. Interest at a rate of 4.25% per year is payable on January 15 and July 15 of each year, beginning on January 15, 2013, until the stated maturity date of July 15, 2022. The terms of the Notes due 2022 are governed by a base indenture and supplemental indenture, dated March 30, 2011 and June 28, 2012, respectively, among the Operating Partnership, as issuer, the Parent Company, as guarantor, and U.S. Bank National Association, as trustee.
	The Operating Partnership may redeem the Notes due 2022, in whole or in part, at any time for cash at a redemption price equal to the greater of (1) 100% of the principal amount of the Notes due 2022 being redeemed; or (2) the sum of the present values of the remaining scheduled payments of principal and interest thereon discounted to the redemption date on a semi-annual basis at the adjusted treasury rate plus 45 basis points, plus in each case, accrued and unpaid interest.
	The terms of the indenture for the Notes due 2022 require compliance with various financial covenants, including limits on the amount of total leverage and secured debt maintained by the Operating Partnership and which require the Operating Partnership to maintain minimum levels of debt service coverage. Management believes that it was in compliance with these covenants as of December 31, 2013.
	Unsecured Senior Term Loan due 2017
	Term Loan due 2017 - U.S. dollar
	On March 30, 2012, the Operating Partnership entered into the $400.0 million Term Loan due 2017 with KeyBank National Association (“KeyBank”) as administrative agent and co-lead arranger, Wells Fargo Securities, LLC as co-lead arranger and Wells Fargo Bank National Association as co-syndication agent, U.S. Bank National Association as co-syndication agent and co-lead arranger and other lenders. The Term Loan due 2017 has a maturity date of March 30, 2017. Subject to the administrative agent’s reasonable discretion, the Operating Partnership may increase the amount of the borrowings to $500.0 million under the Term Loan due 2017 upon satisfying certain conditions. Borrowings under the Term Loan due 2017 are guaranteed by the Parent Company.
Borrowings for the U.S. dollar-denominated debt under the Term Loan due 2017 bear interest at a floating rate equal to, at the Operating Partnership’s option, either (1) reserve adjusted U.S. dollar-LIBOR plus a spread which ranges from 115 to 205 basis points, depending on the Parent Company’s credit ratings, or (2) the highest of (a) the prime rate then in effect plus a spread which ranges from 15 to 120 basis points, (b) the federal funds rate then in effect plus a spread which ranges from 65 to 170 basis points or (c) one-month U.S. dollar-LIBOR plus a spread which ranges from 115 to 205 basis points, in each case, depending on the Parent Company’s credit ratings.
Concurrent with the closing of the Term Loan due 2017 in March 2012, the Operating Partnership entered into interest rate swap agreements, which are intended to have the effect of fixing interest payments associated with $200.0 million of the outstanding balance under the Term Loan due 2017 at approximately 2.81% for a five-year term, subject to change depending on the Parent Company’s credit ratings.
Term Loan due 2017 - GBP
On August 2, 2012, the Operating Partnership amended the Term Loan due 2017 agreement to convert approximately $156.4 million of outstanding borrowings of the Term Loan due 2017 into GBP equal to £100.0 million. Borrowings for the GBP-denominated debt under the Term Loan due 2017 bear interest at a floating rate equal to reserve adjusted GBP-LIBOR plus a spread which ranges from 115 to 205 basis points, depending on the Parent Company’s credit ratings.
The Operating Partnership designated the GBP-denominated debt under the Term Loan due 2017 as a net investment hedge. The Operating Partnership intended to hedge the foreign currency exchange risk attributable to changes in the GBP/U.S. dollar exchange rate on a portion of its net investment in its GBP functional currency subsidiary during the period of investment during which the hedging instrument is outstanding. Variability in the GBP/U.S. dollar exchange rate impacts the Operating Partnership as the financial statements of the GBP functional currency subsidiary are translated each period, with the effect of changes in the GBP/U.S. dollar exchange rate being recorded as foreign currency translation gain or loss in other comprehensive income.
Concurrent with the conversion to GBP denominated debt, the Operating Partnership entered into interest rate swap agreements, which are intended to have the effect of fixing interest payments associated with £100.0 million of the outstanding balance under the Term Loan due 2017 at approximately 2.39% for a five-year term of the Term Loan due 2017, subject to change depending on the Parent Company’s credit ratings.
The Term Loan due 2017 includes certain restrictions and covenants which require compliance with financial covenants relating to the minimum amounts of net worth, fixed charge coverage, unsecured debt service coverage, overall leverage and unsecured leverage ratios, the maximum amount of secured indebtedness and certain investment limitations. The Term Loan due 2017 specifies a number of events of default (some of which are subject to applicable cure periods), including, among others, the failure to make payments when due, noncompliance with covenants and defaults under other agreements or instruments of indebtedness. Upon the occurrence of an event of default, the lenders may terminate the Term Loan due 2017 and declare all amounts outstanding to be immediately due and payable.
On September 24, 2013, the Operating Partnership entered into a second amendment to the Term Loan due 2017, which changed, among other things, (1) the definition of “Capitalization Rate” to mean 7.25% with respect to all projects other than the Company's Center for Life Science | Boston property, and 6.25% with respect to the Center for Life Science | Boston property and (2) certain definitions used to calculate the financial covenants.
Management believes that the Operating Partnership was in compliance with the covenants as of December 31, 2013.
Unsecured Line of Credit and Term Loan due 2018
On July 14, 2011, the Operating Partnership entered into an unsecured credit agreement with KeyBank, as administrative agent and co-lead arranger, Wells Fargo Securities, LLC as co-lead arranger, and certain other lenders. The unsecured credit agreement provided for available borrowings under a revolving line of credit of $750.0 million with a maturity date of March 24, 2018.
On September 24, 2013, the Operating Partnership entered into an amended and restated unsecured credit agreement (the “Amended and Restated Credit Facility”), amending and restating its unsecured credit agreement dated July 14, 2011, as amended. The Amended and Restated Credit Facility provides for aggregate borrowings of up to $1.25 billion, consisting of a $900.0 million revolving line of credit and a $350.0 million Term Loan due 2018, with a maturity date of March 24, 2018. Subject to the administrative agent’s reasonable discretion, the Operating Partnership may increase the amount of the commitments under the Amended and Restated Credit Facility up to $1.8 billion upon satisfying certain conditions. In addition, the Operating Partnership, at its sole discretion, may extend the maturity date to September 24, 2018 after satisfying certain conditions and paying an extension fee. Borrowings under the unsecured line of credit and the Term Loan due 2018 are guaranteed by the Parent Company. In connection with the Amended and Restated Credit Facility, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.
Borrowings under the Amended and Restated Credit Facility bear interest at floating rates equal to, at the Operating Partnership’s option, either (1) reserve-adjusted LIBOR plus a spread which ranges from 92.5 to 170 basis points (with respect to the unsecured line of credit) and a spread which ranges from 95 to 195 basis points (with respect to the Term Loan due 2018), in each case depending on the Parent Company’s credit ratings, or (2) the highest of (a) the prime rate then in effect plus a spread which ranges from 0 to 70 basis points, (b) the federal funds rate then in effect plus a spread which ranges from 50 to 120 basis points, or (c) one-month LIBOR plus a spread which ranges from 92.5 to 170 basis points (with respect to the unsecured line of credit) and a spread which ranges from 95 to 195 basis points (with respect to the Term Loan due 2018), in each case depending on the Parent Company’s credit ratings. In addition, a facility fee is payable on the total $900.0 million capacity of the unsecured line of credit, which ranges from 12.5 to 30 basis points per annum, depending on the Parent Company’s credit ratings.
The Amended and Restated Credit Facility includes certain restrictions and covenants which require compliance with financial covenants relating to the minimum amounts of net worth, fixed charge coverage, unsecured debt service coverage, overall leverage and unsecured leverage ratios, the maximum amount of secured indebtedness and certain investment limitations. The unsecured credit agreement specifies a number of events of default (some of which are subject to applicable cure periods), including, among others, the failure to make payments when due, noncompliance with covenants and defaults under other agreements or instruments of indebtedness. Upon the occurrence of an event of default, the lenders may terminate the revolving line of credit and declare all amounts outstanding to be immediately due and payable. Management believes that the Operating Partnership was in compliance with these covenants as of December 31, 2013.
On September 25, 2013, the Operating Partnership entered into interest rate swap agreements, which are intended to have the effect of fixing interest payments associated with $200.0 million of the Term Loan due 2018 outstanding at approximately 2.2% for a three-year term, subject to adjustment based on the Parent Company's credit ratings. See Note 9 for further details.
Net Investment Hedge
The Operating Partnership designated the GBP denominated debt under the Term Loan due 2017 as a net investment hedge. The Operating Partnership entered into this net investment hedge to protect a designated amount of the Operating Partnership’s net investment in a GBP functional currency subsidiary against the risk of adverse changes in the GBP/U.S. dollar exchange rate (foreign exchange risk). Variability in the GBP/U.S. dollar exchange rate impacts the Operating Partnership (a U.S. dollar functional currency entity) as the financial statements of the GBP functional currency subsidiary are translated each period, with the effect of changes in the GBP/U.S. dollar exchange rate being recorded in accumulated other comprehensive income. When the net investment is sold or substantially liquidated, the balance of the translation adjustment accumulated in other comprehensive income will be reclassified into earnings. The Operating Partnership is hedging the risk of changes in the U.S. dollar equivalent value of a portion of its net investment in its GBP subsidiary attributable to changes in the GBP/U.S. dollar exchange rate during the period of investment during which the hedging instrument is outstanding.
Maturities of Long-Term Debt
As of December 31, 2013, principal payments due for the Operating Partnership’s consolidated indebtedness (excluding debt premiums and discounts) were as follows (in thousands):
2014	$	341,416
2015	30,006
2016	566,516
2017	439,080
2018	523,663
Thereafter (1)	764,153
	$	2,664,834
-1	Includes $180.0 million in principal payments of the Exchangeable Senior Notes based on a contractual maturity date of January 15, 2030.

Earnings_Per_Share_of_the_Pare

Earnings Per Share of the Parent Company	12 Months Ended
	Dec. 31, 2013
Earnings Per Share, Basic and Diluted [Abstract]	'
Earnings Per Share of the Parent Company	'
	Earnings Per Share of the Parent Company
	Grants of restricted stock of the Parent Company and LTIP units of the Operating Partnership in share-based payment transactions are considered participating securities prior to vesting and, therefore, are considered in computing basic earnings per share under the two-class method. The two-class method is an earnings allocation method for calculating earnings per share when a company’s capital structure includes either two or more classes of common stock or common stock and participating securities. Basic earnings per share under the two-class method is calculated based on dividends declared on common shares and other participating securities (“distributed earnings”) and the rights of participating securities in any undistributed earnings, which represents net income remaining after deduction of dividends accruing during the period. The undistributed earnings are allocated to all outstanding common shares and participating securities based on the relative percentage of each security to the total number of outstanding participating securities. Basic earnings per share represents the summation of the distributed and undistributed earnings per share class divided by the total number of shares.
	Through December 31, 2013 all of the Company’s participating securities (including the OP units) received dividends/distributions at an equal dividend/distribution rate per share/unit. As a result, the portion of net income allocable to the weighted-average unvested restricted stock outstanding for the years ended December 31, 2013, 2012 and 2011 has been deducted from net income available to common stockholders to calculate basic earnings per share. The calculation of diluted earnings per share for the years ended December 31, 2013, 2012 and 2011 includes the outstanding OP units (both vested and unvested) in the weighted-average shares, and net income attributable to noncontrolling interests in the Operating Partnership has been added back to net income available to common stockholders. For the year ended December 31, 2013, the Performance Units were dilutive to the calculation of diluted earnings per share as calculated, assuming that December 31, 2013 was the end date of the Performance Units' Performance Period. For the year ended December 31, 2012, the Performance Units were anti-dilutive to the calculation of diluted earnings per share as calculated, assuming that December 31, 2012 was the end date of the Performance Units' Performance Period. For the years ended December 31, 2013, 2012 and 2011, the unvested restricted stock was anti-dilutive to the calculation of diluted earnings per share and was therefore excluded. As a result, diluted earnings per share was calculated based upon net income available to common stockholders less net income allocable to unvested restricted stock and distributions in excess of earnings attributable to unvested restricted stock. In addition, 10,405,224, 10,259,496 and 10,017,858 shares issuable upon settlement of the exchange feature of the Exchangeable Senior Notes were anti-dilutive and were not included in the calculation of diluted earnings per share based on the “if converted” method for the years ended December 31, 2013, 2012 and 2011, respectively. No other shares were considered anti-dilutive for the years ended December 31, 2013, 2012 and 2011.
	Computations of basic and diluted earnings per share (in thousands, except share data) were as follows:
		Years Ended December 31,
		2013			2012			2011
	Basic earnings per share:
	Income from continuing operations	$	47,209		$	16,133		$	42,240
	Income from continuing operations attributable to noncontrolling interests	(565		)	(20		)	(515		)
	Preferred stock dividends	(2,393		)	(14,603		)	(16,033		)
	Cost on redemption of preferred stock	(6,531		)	—			(165		)
	Net income allocable and distributions in excess of earnings to participating securities (continuing operations)	(1,350		)	(1,300		)	(1,172		)
	Income from continuing operations available to common stockholders - basic	36,370			210			24,355
	(Loss) / income from discontinued operations	—			(4,370		)	474
	Loss / (income) from discontinued operations attributable to noncontrolling interests	—			82			(10		)
	(Loss) / income from discontinued operations available to common stockholders - basic	—			(4,288		)	464
	Net income / (loss) available to common stockholders - basic	$	36,370		$	(4,078	)	$	24,819
	Diluted earnings per share:
	Income from continuing operations available to common stockholders - basic	36,370			210			24,355
	Income from continuing operations attributable to noncontrolling interests in Operating Partnership	819			29			559
	Income from continuing operations available to common stockholders - diluted	37,189			239			24,914
	(Loss) / income from discontinued operations available to common stockholders - basic and diluted	—			(4,288		)	464
	(Loss) / income from discontinued operations attributable to noncontrolling interests in the Operating Partnership	—			(82		)	10
	(Loss) / income from discontinued operations available to common stockholders - basic and diluted	—			(4,370		)	474
	Net income / (loss) available to common stockholders - diluted	$	37,189		$	(4,131	)	$	25,388
	Weighted-average common shares outstanding:
	Basic	182,043,391			152,752,086			132,625,915
	Incremental shares from assumed conversion:
	Performance units	63,017			—			—
	Operating partnership and LTIP units	4,290,614			2,948,301			2,983,928
	Diluted	186,397,022			155,700,387			135,609,843
	Basic and diluted earnings per share:
	Income from continuing operations per share available to common stockholders - basic and diluted	$	0.2		$	—		$	0.19
	Loss from discontinued operations per share available to common stockholders - basic and diluted	$	—		$	(0.03	)	$	—
	Net income / (loss) per share available to common stockholders - basic and diluted	$	0.2		$	(0.03	)	$	0.19

Earnings_Per_Unit_of_the_Opera

Earnings Per Unit of the Operating Partnership	12 Months Ended
	Dec. 31, 2013
Partnership Income [Abstract]	'
Earnings Per Unit of the Operating Partnership	'
	Earnings Per Unit of the Operating Partnership
	Restricted units granted in equity-based payment transactions are considered participating securities prior to vesting and, therefore, are considered in computing basic earnings per unit under the two-class method. The two-class method is an earnings allocation method for calculating earnings per unit when a company’s capital structure includes either two or more classes of common equity or common equity and participating securities. Basic earnings per unit under the two-class method is calculated based on distributions declared on the OP units and other participating securities (“distributed earnings”) and the rights of participating securities in any undistributed earnings, which represents net income remaining after deduction of distributions accruing during the period. The undistributed earnings are allocated to all outstanding OP units and participating securities based on the relative percentage of each security to the total number of outstanding participating securities. Basic earnings per unit represents the summation of the distributed and undistributed earnings per unit class divided by the total number of OP units.
	Through December 31, 2013, all of the Operating Partnership’s participating securities received distributions at an equal distribution rate per unit. As a result, the portion of net income allocable to the weighted-average unvested OP units outstanding for the years ended December 31, 2013, 2012 and 2011, has been deducted from net income available to unitholders to calculate basic earnings per unit. For the years ended December 31, 2013, 2012 and 2011, the unvested OP units were anti-dilutive to the calculation of earnings per unit and were therefore excluded from the calculation of diluted earnings per unit, and diluted earnings per unit is calculated based upon net income attributable to unitholders. For the year ended December 31, 2013, the Performance Units were dilutive to the calculation of diluted earnings per unit as calculated, assuming that December 31, 2013 was the end date of the Performance Units’ Performance Period. For the year ended December 31, 2012, the Performance Units were anti-dilutive to the calculation of diluted earnings per share as calculated, assuming that December 31, 2012 was the end date of the Performance Units' Performance Period. In addition, 10,405,224, 10,259,496 and 10,017,858 units issuable upon settlement of the exchange feature of the Exchangeable Senior Notes were anti-dilutive and were not included in the calculation of diluted earnings per unit based on the “if converted” method for the years ended December 31, 2013, 2012 and 2011, respectively. No other units were considered anti-dilutive for the years ended December 31, 2013, 2012 or 2011.
	Computations of basic and diluted earnings per unit (in thousands, except unit data) were as follows:
		Years Ended December 31,
		2013			2012			2011
	Basic and diluted earnings per unit:
	Income from continuing operations	$	47,209		$	16,133		$	42,240
	Loss from continuing operations attributable to noncontrolling interests	254			8			44
	Preferred unit distributions	(2,393		)	(14,603		)	(16,033		)
	Cost on redemption of preferred units	(6,531		)	—			(165		)
	Net income allocable and distributions in excess of earnings to participating securities (continuing operations)	(1,354		)	(1,326		)	(1,220		)
	Income from continuing operations available to unitholders - basic and diluted	37,185			212			24,866
	(Loss) / income from discontinued operations - basic and diluted	—			(4,370		)	474
	Net income / (loss) available to unitholders - basic and diluted	$	37,185		$	(4,158	)	$	25,340
	Weighted-average units outstanding:
	Basic	186,333,292			155,670,931			135,549,934
	Incremental units from assumed conversion:
	Performance units	63,017			—			—
	Diluted	186,396,309			155,670,931			135,549,934
	Basic and diluted earnings per unit:
	Income from continuing operations per unit available to unitholders - basic and diluted	$	0.2		$	—		$	0.19
	Loss from discontinued operations per share available to unitholders - basic and diluted	$	—		$	(0.03	)	$	—
	Net income / (loss) per unit available to unitholders, basic and diluted	$	0.2		$	(0.03	)	$	0.19

Investment_in_Unconsolidated_P

Investment in Unconsolidated Partnerships	12 Months Ended
	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]	'
Investment in Unconsolidated Partnerships	'
	Investment in Unconsolidated Partnerships
	The accompanying consolidated financial statements include investments in two limited liability companies with Prudential Real Estate Investors (“PREI”), 10165 McKellar Court, L.P. (“McKellar Court”), a limited partnership with Quidel Corporation, the tenant which occupies the McKellar Court property and BioPark Fremont, LLC ("BioPark Fremont"), a limited liability company with RPC Poppleton, LLC. General information on the PREI limited liability companies, the McKellar Court partnership and BioPark Fremont (each referred to in this footnote individually as a “partnership” and collectively as the “partnerships”) as of December 31, 2013 was as follows:
	Name	Partner		Company’s		Company’s		Date Acquired
				Ownership		Economic
				Interest		Interest
	PREI I LLC (1)	PREI		20%		20%		April 4, 2007
	PREI II LLC	PREI		20%		20%		April 4, 2007
	McKellar Court (2)	Quidel Corporation		22%		22%		September 30, 2004
	BioPark Fremont (3)	RPC Poppleton, LLC		50%		50%		May 31, 2013
	-1	PREI I LLC owns two properties in Cambridge, Massachusetts. At December 31, 2013, there were $139.0 million in outstanding borrowings on a secured loan facility held by a wholly-owned subsidiary of PREI I LLC, with a contractual interest rate of 3.17% (including the applicable credit spread) and a maturity date of August 13, 2014.
	-2	The Company’s investment in the McKellar Court partnership (maximum exposure to losses) was approximately $12.0 million at December 31, 2013. The Company’s economic interest in the McKellar Court partnership entitles it to 75% of the extraordinary cash flows after repayment of the partners’ capital contributions and 22% of the operating cash flows.
	-3	The Company's partnership interest was acquired in connection with the Company's merger with Wexford.
	The condensed combined balance sheets for all of the Company’s unconsolidated partnerships were as follows (in thousands):
		December 31,				December 31,
		2013				2012
	Assets:
	Investments in real estate, net	$	262,753			$	257,666
	Cash and cash equivalents (including restricted cash)	3,855				1,968
	Other assets	5,301				4,370
	Total assets	$	271,909			$	264,004
	Liabilities and members’ equity:
	Mortgage notes payable and secured loan	$	151,968			$	149,255
	Other liabilities	12,102				5,988
	Members’ equity	107,839				108,761
	Total liabilities and members equity	$	271,909			$	264,004
	Company’s net investment in unconsolidated partnerships	$	32,137			$	32,367
	The selected data and results of operations for the unconsolidated partnerships were as follows (in thousands):
			Years Ended December 31,
			2013				2012			2011
	Total revenues		$	12,930			$	8,823		$	8,567
	Total expenses		(21,589		)		(19,939		)	(19,868		)
	Loss from continuing operations		(8,659		)		(11,116		)	(11,301		)
	Gain on sale of discontinued operations (1)		—				—			22,927
	Loss from discontinued operations		—				—			(6,677		)
	Net (loss) / income		$	(8,659	)		$	(11,116	)	$	4,949
	Company’s equity in net loss of unconsolidated partnerships		$	(905	)		$	(1,389	)	$	(2,489	)
	Fees earned by the Company (2)		$	260			$	90		$	1,117
	-1	During the year ended December 31, 2011, PREI I LLC recorded a gain on sale of discontinued operations upon sale of certain properties to the Company. In accordance with the equity method of accounting, the Company's share of the equity in net income in PREI I LLC excludes any gain on sale since such gain was generated upon sale of the properties to the Company. The Company recorded a gain on revaluation of the acquired unconsolidated partnership.
	-2	The Company acts as the operating member or partner, as applicable, and day-to-day manager for the partnerships. The Company is entitled to receive fees for providing construction and development services (as applicable) and management services to the PREI joint ventures, which are reflected in tenant recoveries and other income in the consolidated statements of operations.

Derivatives_and_Other_Financia

Derivatives and Other Financial Instruments	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Derivatives and Other Financial Instruments	'
	Derivatives and Other Financial Instruments
	The Company is exposed to the effect of changes in interest rates on the Operating Partnership’s U.S. dollar-LIBOR-based and GBP-LIBOR-based debt. The Company limits this risk by following established risk management policies and procedures including the use of derivatives. The Company’s objectives in using interest rate derivatives are to add stability to interest expense and to manage its exposure to interest rate movements related to the Operating Partnership’s LIBOR-based debt. To accomplish these objectives, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The interest rate swaps hedge the Company’s exposure to the variability on expected cash flows attributable to changes in interest rates. These interest rate swaps are currently intended to hedge interest payments associated with the Operating Partnership’s Term Loan due 2017 and Term Loan due 2018.
	On March 30, 2012, the Company entered into four interest rate swaps with an aggregate notional amount of $200.0 million under which at each monthly settlement date the Company either (1) receives the difference between a fixed interest rate (the “USD Strike Rate”) and one-month U.S. dollar-LIBOR if the USD Strike Rate is less than one-month U.S. dollar-LIBOR or (2) pays such difference if the USD Strike Rate is greater than one-month U.S. dollar-LIBOR. The interest rate swaps hedge the Company’s exposure to the variability on expected cash flows attributable to changes in interest rates on the first interest payments, due on the date that is on or closest after each swap’s settlement date, associated with the amount of one-month U.S. dollar-LIBOR-based debt equal to each swap’s notional amount. These interest rate swaps, with a notional amount of $200.0 million, are currently intended to hedge interest payments associated with the Operating Partnership’s Term Loan due 2017 - U.S. Dollar. No initial investment was made to enter into the interest rate swap agreements.
	On August 2, 2012, in connection with the conversion of a portion of the outstanding borrowings under the Term Loan due 2017 into GBP (for further discussion, see Note 5 above), the Company entered into two interest rate swaps with an aggregate notional amount of £100.0 million under which at each monthly settlement date the Company either (1) receives the difference between a fixed interest rate (the “GBP Strike Rate”) and one-month GBP-LIBOR if the GBP Strike Rate is less than one-month GBP-LIBOR or (2) pays such difference if the GBP Strike Rate is greater than one-month GBP-LIBOR. The interest rate swaps hedge the Company’s exposure to the variability on expected cash flows attributable to changes in interest rates on the first interest payments, due on the date that is on or closest after each swap’s settlement date, associated with the amount of one-month GBP-LIBOR-based debt equal to each swap’s notional amount. These interest rate swaps, with a notional amount of £100.0 million, are currently intended to hedge interest payments associated with the Operating Partnership’s Term Loan due 2017 - GBP. No initial investment was made to enter into the interest rate swap agreements.
	On September 25, 2013, the Operating Partnership entered into three interest rate swaps with an aggregate notional amount of $200.0 million under which at each monthly settlement date the Company either (1) receives the difference between a fixed interest rate (the “Strike Rate”) and one-month U.S. dollar-LIBOR if the Strike Rate is less than one-month U.S. dollar-LIBOR or (2) pays such difference if the Strike Rate is greater than one-month U.S. dollar-LIBOR. The interest rate swaps hedge the Company’s exposure to the variability on expected cash flows attributable to changes in interest rates on the first interest payment, due date on or after each swap’s settlement date, associated with the amount of one-month U.S. dollar-LIBOR-based debt equal to each swap’s notional amount. These interest rate swaps, with a notional amount of $200.0 million, are currently intended to hedge interest payments associated with the Operating Partnership’s Term Loan due 2018 for three years. No initial investment was made to enter into the interest rate swap agreements.
	As of December 31, 2013, the Company had deferred interest costs of approximately $35.4 million in accumulated other comprehensive loss related to forward starting swaps, which were settled with the corresponding counterparties in 2009. The forward starting swaps were entered into to mitigate the Company’s exposure to the variability in expected future cash flows attributable to changes in future interest rates associated with a forecasted issuance of fixed-rate debt, with interest payments for a minimum of ten years. The deferred interest costs will be amortized as additional interest expense over a remaining period of approximately five years.
	The following is a summary of the terms of the interest rate swaps and their respective fair-values (dollars in thousands):
												Fair-Value(1)
		Notional Amount										December 31,			December 31,
						Strike Rate			Effective Date	Expiration Date		2013			2012
	Interest rate swaps	$	200,000			1.163	%		March 30, 2012	March 30, 2017		$	(1,876	)	$	(4,826	)
	Interest rate swaps	200,000				0.701	%		October 1, 2013	October 1, 2016		(288		)	—
	Interest rate swaps(2)	82,595				0.731	%		August 2, 2012	March 30, 2017		1,545			(216		)
	Interest rate swaps(2)	82,595				0.7425	%		August 2, 2012	March 30, 2017		1,519			(243		)
	Total interest rate swaps	$	565,190									$	900		$	(5,285	)
	-1	Fair-value of derivative instruments does not include any related accrued interest payable, which is included in accrued expenses on the accompanying consolidated balance sheets. Derivative valuations are classified in Level 2 of the fair-value hierarchy. Assets are included in other assets and liabilities are included in accounts payable, accrued expenses and other liabilities on the accompanying consolidated balance sheets.
	-2	Translation to U.S. dollars is based on exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively.
	For derivatives designated as cash flow hedges, the effective portion of changes in the fair-value of the derivative is initially reported in other comprehensive income (outside of earnings) and subsequently reclassified to earnings in the period in which the hedged forecasted transaction affects earnings. During the years ended December 31, 2013, 2012 and 2011, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt. The ineffective portion of the change in fair-value of the derivatives is recognized directly in earnings. No portion of the derivatives designated as cash flow hedges were classified as ineffective during the years ended December 31, 2013 and 2012.
	The Company’s use of proceeds from its March 2011 unsecured debt offering to repay a portion of the outstanding indebtedness on its unsecured line of credit caused the amount of variable-rate indebtedness to fall below the combined notional value of the outstanding interest rate swaps on March 30, 2011, causing the Company to be overhedged. As a result, the Company re-performed tests to assess the effectiveness of its interest rate swaps. Although the interest rate swaps with an aggregate notional amount of $150.0 million passed the assessment tests and the $115.0 million swap continued to qualify for hedge accounting, the $35.0 million swap no longer qualified for hedge accounting due to the lack of variable rate debt expected to be outstanding during the remaining term of the swap. As a result, the Company accelerated the reclassification of amounts deferred in accumulated other comprehensive loss to earnings related to the hedged forecasted transactions that became probable of not occurring during the period in which the Company was overhedged. This resulted in a cumulative charge to earnings for the year ended December 31, 2011 of approximately $1.0 million. From the date that hedge accounting was discontinued on the $35.0 million swap, changes in the fair-value associated with this interest rate swap were recorded directly to earnings, resulting in the recognition of a gain of approximately $12,000 for the year ended December 31, 2011, which is included as a component of other expense. These swaps expired in August 2011.
	During the year ended December 31, 2013, the Company recorded a total gain on derivative instruments of $416,000, primarily related to changes in the fair-value of other derivative instruments. During the year ended December 31, 2012, the Company recorded a total loss on derivative instruments of $9,000, primarily related to changes in the fair-value of other derivative instruments. During the year ended December 31, 2011, the Company recorded total loss on derivative instruments of $544,000, primarily related to the reduction in the amount of the variable-rate indebtedness relating to the $150.0 million interest rate swaps, hedge ineffectiveness on cash flow hedges due to mismatches in maturity dates and interest rate reset dates between the interest rate swaps and corresponding debt and changes in the fair-value of other derivative instruments. Gains and losses on derivative instruments are included in other expense within the consolidated statement of operations.
	Amounts reported in accumulated other comprehensive loss related to derivatives will be reclassified to earnings during the period in which the hedged forecasted transaction affects earnings. The change in net unrealized gain / (loss) on derivative instruments includes reclassifications of net unrealized losses from accumulated other comprehensive loss as (1) an increase to interest expense of $9.5 million, $8.5 million and $10.4 million for the years ended December 31, 2013, 2012, and 2011, respectively, and (2) a gain on derivative instruments of $416,000, and losses of $9,000 and $544,000 for the years ended December 31, 2013, 2012, and 2011, respectively. During the next twelve months, the Company estimates that an additional $9.9 million will be reclassified from accumulated other comprehensive loss as an increase to interest expense. In addition, for the years ended December 31, 2013, 2012, and 2011, approximately $326,000, $118,000 and $236,000, respectively, of settlement payments on interest rate swaps have been deferred in accumulated other comprehensive loss and will be amortized over the useful lives of the related development or redevelopment projects.
	The following is a summary of the amount of gain / (loss) recognized in other comprehensive income related to the derivative instruments (in thousands):
			Year Ended
			December 31,
			2013				2012			2011
	Amount of gain / (loss) recognized in other comprehensive income (effective portion):
	Cash flow hedges
	Interest rate swaps		$	3,497			$	(6,863	)	$	(104	)
	Amount of loss reclassified from accumulated other comprehensive loss to income (effective portion):
	Cash flow hedges
	Interest rate swaps (1)		$	(2,619	)		$	(1,578	)	$	(3,385	)
	Forward starting swaps (2)		(6,832		)		(6,933		)	(7,027		)
	Total interest rate swaps		$	(9,451	)		$	(8,511	)	$	(10,412	)
	Amount of gain / (loss) recognized in income (ineffective portion and amount excluded from effectiveness testing):
	Cash flow hedges
	Interest rate swaps		$	—			$	—		(544		)
	Total interest rate swaps		—				—			$	(544	)
	Other derivative instruments		416				(9		)	—
	Total gain / (loss) on derivative instruments		$	416			$	(9	)	$	(544	)
	-1	Amount represents payments made to swap counterparties for the effective portion of interest rate swaps that were recognized as an increase to interest expense for the periods presented (the amount was recorded as an increase and corresponding decrease to accumulated other comprehensive loss in the same accounting period).
	-2	Amount represents reclassifications of deferred interest costs from accumulated other comprehensive loss to interest expense related to the Company’s previously settled forward starting swaps.

FairValue_of_Financial_Instrum

Fair-Value of Financial Instruments	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair Value Disclosures	'
	Fair-Value of Financial Instruments
	The Company’s disclosures of estimated fair-value of financial instruments at December 31, 2013 and December 31, 2012 were determined using available market information and appropriate valuation methods. Considerable judgment is necessary to interpret market data and develop estimated fair-value. The use of different market assumptions or estimation methods may have a material effect on the estimated fair-value amounts.
	The carrying amounts for cash and cash equivalents, accounts receivable, accounts payable, accrued expenses and other liabilities approximate fair-value due to the short-term nature of these instruments.
	The Company utilizes quoted market prices to estimate the fair-value of its fixed-rate and variable-rate debt, when available. If quoted market prices are not available, the Company calculates the fair-value of its mortgage notes payable and other fixed-rate debt based on a currently available market rate assuming the loans are outstanding through maturity and considering the collateral. In determining the current market rate for fixed-rate debt, a market credit spread is added to the quoted yields on federal government treasury securities with similar terms to debt. In determining the current market rate for variable-rate debt, a market credit spread is added to the current effective interest rate. The carrying values of interest rate swaps are reflected at their fair-values.
	At December 31, 2013 and December 31, 2012, the aggregate fair-value and the carrying value of the Company’s financial instruments were as follows (in thousands):
		December 31, 2013						December 31, 2012
		Fair-Value (1)			Carrying Value			Fair-Value (1)		Carrying Value
	Mortgage notes payable, net	$	730,394		$	709,324		$	605,948	$	571,652
	Exchangeable Senior Notes	202,626			180,000			209,484		180,000
	Notes due 2016, net	417,040			398,787			421,400		398,289
	Notes due 2020, net	275,600			248,210			292,725		247,984
	Notes due 2022, net	240,400			248,086			261,750		247,904
	Term Loan due 2017 - U.S. dollar	244,751			243,596			243,596		243,596
	Term Loan due 2017 - GBP (2)	165,969			165,190			161,860		161,860
	Term Loan due 2018	350,000			350,000			—		—
	Unsecured line of credit	128,000			128,000			118,000		118,000
	Derivative instruments (3)	(1,316		)	(1,316		)	5,285		5,285
	Available-for-sale securities	19,566			19,566			390		390
	-1	Fair-values of debt and derivative instruments are classified in Level 2 of the fair-value hierarchy. Fair-value of available-for-sale securities are classified in Level 1 of the fair-value hierarchy.
	-2	The principal balance represents the U.S. dollar amount based on the exchange rate of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively.
	-3	The Company’s derivative instruments are reflected in other assets and in accounts payable, accrued expenses and other liabilities on the accompanying consolidated balance sheets based on their respective balances (see Note 9).

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2013
Business Combinations [Abstract]	'
Business Combination Disclosure	'
	Acquisitions
	The Company acquired the following properties during the year ended December 31, 2013. The table below reflects the purchase price allocation for these acquisitions, excluding the merger with Wexford, which is discussed below, and the purchase of properties with approximately 274,000 and 300,000 square feet of pre-development and development potential, respectively, for approximately $13.4 million recorded as investments in real estate (in thousands):
	Property		Acquisition Date		Investments in Real Estate				In-Place Lease		Management		Below Market Lease			Acquisition Date Fair- Value
											Agreement
	Woodside Technology Park		February 28, 2013		$	78,681			$	8,162	$	865	$	(708	)	$	87,000
	The Campus at Lincoln Centre		March 20, 2013		37,000				—		—		—			37,000
	320 Charles Street		June 18, 2013		47,018				4,578		—		(2,078		)	49,518
	Total				$	162,699			$	12,740	$	865	$	(2,786	)	$	173,518
	Weighted average intangible amortization life (in months)								61		108		18
	Wexford Merger
	On May 31, 2013, the Company completed a merger with Wexford. The purchase price allocations of the fair-value of assets acquired, liabilities assumed and consideration paid in the Wexford merger are presented below (in thousands):
		At Acquisition
	Assets:
	Investments in real estate	$	659,517
	Cash and cash equivalents	5,182
	Accounts receivable, net	1,537
	Deferred leasing costs (1)	52,670
	Other assets (2)	89,631
	Total assets	$	808,537
	Liabilities:
	Mortgage notes payable (3)	254,735
	Other liabilities (4)	69,270
	Total liabilities	$	324,005
	Fair value of net assets acquired	$	484,532
	Cash consideration paid for Wexford	$	345,268
	Equity consideration paid for Wexford (5)	123,596
	Contingent consideration in merger with Wexford (6)	15,668
	Total consideration for Wexford	$	484,532
	-1	$52.7 million of acquired in-place leases with a weighted-average lease term of approximately 10.9 years are included in deferred leasing costs.
	-2	$9.6 million of acquired above-market leases with a weighted-average lease term of approximately 11.6 years and $11.0 million of acquired below-market ground leases with a weighted-average lease term of approximately 51.7 years are included in other assets.
	-3	$8.7 million of debt premiums with a weighted-average term of approximately 9.2 years are included in mortgage notes payable, net.
	-4	$31.4 million of acquired below-market leases with a weighted-average lease term of approximately 13.4 years and $2.5 million of acquired above-market ground leases with a weighted-average lease term of approximately 64.0 years are included in other liabilities.
	-5	Consists of 5,568,227 shares of the Parent Company's common stock and 336,960 operating partnership units.
	-6	Includes potential additional consideration to be paid to the seller upon the achievement of certain pipeline development milestones.
	Wexford - Variable Interest Entities
	Wexford is a party to certain contractual arrangements with tax credit investors (“TCIs”) that were established to enable the TCIs to receive the benefits of historic tax credits (“HTCs”) and/or new market tax credits (“NMTCs”) for certain properties owned by Wexford. At May 31, 2013, Wexford owned seven properties that had syndicated HTCs or NMTCs, or both, to TCIs. At December 31, 2013, Wexford owned nine properties that had syndicated HTCs or NMTCs, or both, to TCIs.
	Historic Tax Credits and New Market Tax Credits
	Capital contributions are made by TCIs into special purpose entities that ultimately invest these funds in the entity that owns the subject property that generates the tax credits. The TCIs are allocated substantially all of the tax credits and hold only a noncontrolling interest in the economic risk and rewards of the special purpose entities. HTCs are delivered to the TCI upon substantial completion of the project. NMTCs are allowed for up to 39% of a qualified investment and are delivered to the TCI after the investment has been funded and spent on a qualified business. HTCs are subject to 20% recapture per year beginning one year after the completion of the historic rehabilitation of the subject property. NMTCs are subject to 100% recapture until the end of the seventh year following the qualifying investment. The Company has provided the TCIs with certain guarantees which protect the TCIs from loss should a tax credit recapture event occur. The contractual arrangements with the TCIs include a put/call provision whereby the Company may be obligated or entitled to repurchase the ownership interest of the TCIs in the special purpose entities at the end of the tax credit recapture period. The Company anticipates that either the TCIs will exercise their put rights or the Company will exercise its call rights; however, the Company believes that the put rights are more likely to be exercised.
	The Company has determined that the special purpose entities are VIEs, since there is insufficient capital to finance their activities without further subordinated financial support. The Company has determined that it is the primary beneficiary of these VIEs, because it has the authority to direct the activities which most significantly impact their economic performance.
	The portion of the TCI’s capital contribution that is attributed to the put is recorded at fair-value at inception and is accreted to the expected put price as interest expense in the consolidated statement of operations. At December 31, 2013, approximately $4.3 million of put liabilities were included in other liabilities in the consolidated balance sheets. The remaining balance of the TCI’s capital contribution is initially recorded in other liabilities in the consolidated balance sheets and will be relieved, upon delivery of the tax credit to the TCI, as a reduction in the carrying value of the subject property, net of allocated expenses. During the year ended December 31, 2013, $34.4 million of tax credits, net of costs and estimated put payments, were contributed by TCIs which were recorded as other liabilities in the consolidated balance sheets, of which $22.4 million of tax credits have been delivered to the TCIs and were reclassified as a reduction of the carrying value of the subject property. Direct and incremental costs incurred in structuring the transaction are deferred and will be recognized as an increase in the cost basis of the subject property upon the recognition of the related tax credit as discussed above.
	The Company has determined that certain special purpose entities owning properties under development are VIEs, since there is insufficient capital to finance the remaining development activities without further subordinated financial support. The Company has determined it is the primary beneficiary of these VIEs, because it has the authority to direct the activities which most significantly impact their economic performance. Selected financial data of the VIEs at December 31, 2013 consisted of the following (in thousands):
		December 31,
		2013
	Investment in real estate, net	$	177,901
	Total assets	198,968
	Total liabilities	60,197
	Pro Forma Results of the Parent Company
	The unaudited pro forma revenues and operating income of the Parent Company, including the acquisitions that occurred in 2013 as if they had taken place on January 1, 2012, are as follows (in thousands, except per share amounts):
			Year Ended December 31,
			2013				2012
	Total revenues		$	666,904			$	590,415
	Net income / (loss) available to common stockholders		36,981				(19,493		)
	Net income / (loss) per share available to common stockholders - basic and diluted		$	0.2			$	(0.13	)
	Pro forma data may not be indicative of the results that would have been reported had the acquisitions actually occurred as of January 1, 2012, nor is it intended to be a projection of future results.
	Pro Forma Results of the Operating Partnership
	The unaudited pro forma revenues and operating income of the Operating Partnership, including the acquisitions that occurred in 2013 as if they had taken place on January 1, 2012, are as follows (in thousands, except per unit amounts):
			Year Ended December 31,
			2013				2012
	Total revenues		$	666,904			$	590,415
	Net income / (loss) available to unitholders		37,800				(19,547		)
	Net income / (loss) per unit available to unitholders - basic and diluted		$	0.2			$	(0.13	)
	Pro forma data may not be indicative of the results that would have been reported had the acquisitions actually occurred as of January 1, 2012, nor is it intended to be a projection of future results.
	Revenues of approximately $45.3 million and net loss of approximately $2.6 million associated with properties acquired in 2013 listed above are included in the consolidated statements of operations for the year ended December 31, 2013 for both the Parent Company and the Operating Partnership.

Discontinued_Operations

Discontinued Operations	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	Discontinued Operations
	In April 2012, the Company completed the exchange of an operating property on Forbes Boulevard in South San Francisco for an office property located in Redwood City, California. As a result, during the year ended December 31, 2012, the Company reclassified the Forbes Boulevard property as a discontinued operation. The table below reflects the details of the property and the exchange (in thousands):
	Property		Date of Sale	Original Acquisition Date		Sales Price (1)			Impairment loss
	Forbes Boulevard		April 27, 2012	September 5, 2007		$	28,000		$	(4,552	)
	-1	The sales price was equal to the fair-value of the office property received as consideration in the exchange with the independent third party.
	The results of operations of the Forbes Boulevard property are reported as discontinued operations for all periods presented in the accompanying consolidated financial statements. The following table summarizes the revenue and expense components that comprise income / (loss) from discontinued operations (in thousands):
		Year Ended
		December 31,
		2013			2012			2011
	Total revenues	$	—		$	454		$	1,499
	Total expenses	—			272			1,025
	Income from discontinued operations before impairment loss	—			182			474
	Impairment loss	—			(4,552		)	—
	(Loss) / income from discontinued operations	$	—		$	(4,370	)	$	474
	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.

Incentive_Award_Plan_Incentive

Incentive Award Plan Incentive Award Plan	12 Months Ended
	Dec. 31, 2013
Incentive Award Plan (Summary of Unvested Restricted Stock and LTIP Units) [Abstract]	'
Disclosure of Compensation Related Costs, Share-based Payments [Text Block]	'
	Selected data of the Company’s incentive award plan is presented below (in thousands, except share and period amounts):
		Years Ended December 31,
		2013			2012		2011
	Aggregate value of restricted stock/LTIP Units granted	$	13,234		$	7,300	$	11,612
	Aggregate value of Performance Units granted	$	4,973		$	3,329	$	—
	Fair-value of stock/LTIP Units vested	$	13,321		$	9,502	$	8,547
	Stock-based compensation expense recognized in general and administrative expenses and rental operations expense - restricted stock/LTIP Units	$	10,134		$	9,556	$	7,582
	Stock-based compensation expense recognized in general and administrative expenses - Performance Units	$	2,445		$	1,974	$	—
	Shares surrendered to the Company and retired in lieu of cash payments for taxes due on the vesting of restricted stock	253,671			178,915		129,342
	Data at period end:
	Total compensation to be expensed related to unvested awards in future periods - restricted stock	$	17,145
	Weighted-average expense period (in years) - restricted stock	2.6
	Total compensation to be expensed related to unvested awards in future periods - Performance Units	$	2,528
	Weighted-average expense period (in years) - Performance Units	1.5
Incentive Award Plan Selected Data [Table Text Block]	'
	Incentive Award Plan
	The Company has adopted the 2013 Amendment and Restatement of the BioMed Realty Trust, Inc. and BioMed Realty, L.P. 2004 Incentive Award Plan (the “Plan”). The Plan provides for grants to directors, employees and consultants of the Company and the Operating Partnership (and their respective subsidiaries) of stock options, restricted stock, LTIP units, stock appreciation rights, dividend equivalents, and other incentive awards. The Company has reserved 10,740,000 shares of common stock for issuance pursuant to the Plan, subject to adjustments as set forth in the Plan. As of December 31, 2013, 6,896,224 shares of common stock or awards convertible into or exchangeable for common stock remained available for future issuance under the Plan. Each LTIP unit and each Performance Unit issued will count as one share of common stock for purposes of calculating the limit on shares that may be issued. Compensation cost for these incentive awards is measured based on the fair-value of the award on the grant date (fair-value is calculated based on the closing price of the Company’s common stock on the date of grant) and is recognized as expense over the respective vesting period, which for restricted stock awards and LTIP units is generally four to five years. Fully vested incentive awards may be settled for either cash or stock depending on the Company’s election and the type of award granted. Participants are entitled to cash dividends and may vote such awarded shares, but the sale or transfer of such shares is limited during the restricted or vesting period. The restricted stock grants may only be settled for stock whereas the LTIP units may be redeemed for either cash or common stock, at the Company’s election.
	The Parent Company has awarded Performance Units to certain of its executive officers, which represent the maximum number of Performance Units that may vest. Each Performance Unit represents a contingent right to receive one share of the Parent Company’s common stock if vesting conditions are satisfied. Performance Units vest at the end of designated time periods (each, a “Performance Period”) based upon the Parent Company’s total stockholder return relative to its peer group (the “Market Conditions”). The grant date fair-value of the Performance Units was estimated using a Monte Carlo simulation which considered the likelihood of achieving the Market Conditions. The Monte Carlo simulation uses a statistical formula underlying the Black-Scholes and binomial formulas, and such simulation was run approximately 100,000 times. For each simulation, the value of the payoff was calculated at the end of the respective Performance Period and was then discounted to the grant date at a risk-free interest rate. The expected value of the Performance Units on the grant date was determined by simulating the total shareholder return for the Company and the peer group considering the stock price variance for each of the peer group companies, compared to each other and the Company's stock estimating the rank of the Company's stock. The valuation was performed in a risk-neutral framework, so no assumption was made with respect to an equity risk premium. Other significant assumptions used in the valuation included an expected term of 24 and 36 months, an average risk-free interest rate of 0.35%, and an average dividend yield of 4.41%. No dividends will be paid or accrued on the Performance Units, and shares of the Parent Company’s common stock will not be issued until vesting of the Performance Units occurs.
	A summary of the Company’s unvested restricted stock and LTIP units is presented below:
		Unvested Restricted Shares/LTIP Units		Weighted Average Grant-Date Fair-Value
	Balance at December 31, 2010	1,588,060		$	15.15
	Granted	630,337		18.38
	Vested	(467,120	)	16.03
	Forfeited	(30,215	)	16.17
	Balance at December 31, 2011	1,721,062		16.09
	Granted	395,350		18.46
	Vested	(520,258	)	15.17
	Forfeited	(35,642	)	15.97
	Balance at December 31, 2012	1,560,512		17
	Granted	657,106		20.33
	Vested	(665,808	)	15.91
	Forfeited	(39,805	)	18.15
	Balance at December 31, 2013	1,512,005		$	18.91
	Selected data of the Company’s incentive award plan is presented below (in thousands, except share and period amounts):
		Years Ended December 31,
		2013			2012		2011
	Aggregate value of restricted stock/LTIP Units granted	$	13,234		$	7,300	$	11,612
	Aggregate value of Performance Units granted	$	4,973		$	3,329	$	—
	Fair-value of stock/LTIP Units vested	$	13,321		$	9,502	$	8,547
	Stock-based compensation expense recognized in general and administrative expenses and rental operations expense - restricted stock/LTIP Units	$	10,134		$	9,556	$	7,582
	Stock-based compensation expense recognized in general and administrative expenses - Performance Units	$	2,445		$	1,974	$	—
	Shares surrendered to the Company and retired in lieu of cash payments for taxes due on the vesting of restricted stock	253,671			178,915		129,342
	Data at period end:
	Total compensation to be expensed related to unvested awards in future periods - restricted stock	$	17,145
	Weighted-average expense period (in years) - restricted stock	2.6
	Total compensation to be expensed related to unvested awards in future periods - Performance Units	$	2,528
	Weighted-average expense period (in years) - Performance Units	1.5

Commitments_and_Contingencies_

Commitments and Contingencies Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies [Abstract]	'
Commitments and Contingencies Disclosure [Text Block]	'
	Commitments and Contingencies
	Concentration of Credit Risk
	Life science entities comprise the vast majority of the Company’s tenant base. Because of the dependence on a single industry, adverse conditions affecting that industry will more adversely affect our business. Two of the Company’s tenants, Human Genome Sciences, Inc., a wholly owned subsidiary of GlaxoSmithKline plc, and Vertex Pharmaceuticals Incorporated, comprised 10.8% and 7.7%, or $48.0 million and $34.5 million, respectively, of rental revenues for the year ended December 31, 2013; 12.2% and 8.5%, or $48.0 million and $33.4 million, respectively, of rental revenues for the year ended December 31, 2012; and 14.5% and 10.0%, or $48.0 million and $33.2 million, respectively, of rental revenues for the year ended December 31, 2011. These tenants are located in the Company’s Maryland, and Boston and San Diego markets, respectively. The inability of these tenants to make lease payments could materially adversely affect the Company’s business.
	The Company generally does not require collateral or other security from our tenants, other than security deposits or letters of credit in select cases.
	Construction and Other Related Commitments
	As of December 31, 2013, the Company had approximately $415.8 million outstanding in commitments related to the funding of the construction loan, tenant improvements, leasing commissions, and construction-related capital expenditures, with approximately $350.5 million expected to be paid in 2014, approximately $64.2 million expected to be paid in 2015 and 2016, and approximately $1.2 million expected to be paid in 2017 and 2018.
	Ground Leases
	As of December 31, 2013, the Company had approximately $513.2 million outstanding in commitments related to ground leases with approximately $4.5 million expected to be paid in 2014, approximately $9.6 million expected to be paid in 2015 and 2016, approximately $10.3 million expected to be paid in 2017 and 2018 and approximately $488.8 million expected to be paid thereafter.
	Insurance
	The Company carries insurance coverage on its properties with policy specifications and insured limits that it believes are adequate given the relative risk of loss, cost of the coverage and standard industry practice. However, certain types of losses (such as from the perils of earthquakes, windstorms, terrorism and floods) may be either uninsurable or not economically insurable. Further, certain of the properties are located in areas that are subject to earthquake activity, windstorms and floods. Should a property sustain damage as a result of an earthquake, windstorm or flood, the Company may incur losses due to insurance deductibles, co-payments on insured losses or uninsured losses. Should an uninsured loss occur, the Company could lose some or all of its capital investment, cash flow and anticipated profits related to one or more properties.
	Environmental Matters
	The Company follows a policy of monitoring its properties for the presence of hazardous or toxic substances. The Company is not aware of any environmental liability with respect to the properties that would have a material adverse effect on the Company’s business, assets or results of operations. There can be no assurance that such a material environmental liability does not exist. The existence of any such material environmental liability could have an adverse effect on the Company’s results of operations and cash flow. The Company carries environmental remediation insurance for its properties. This insurance, subject to certain exclusions and deductibles, covers the cost to remediate environmental damage caused by future spills or the historic presence of previously undiscovered hazardous substances, as well as third-party bodily injury and property damage claims related to the release of hazardous substances.
	Tax Indemnification Agreements and Minimum Debt Requirements
	As a result of the contribution of properties to the Operating Partnership, the Company has indemnified the contributors of the properties against adverse tax consequences if it directly or indirectly sells, exchanges or otherwise disposes of the properties in a taxable transaction before August 11, 2014, the ten-year anniversary of the completion of the Company’s initial public offering. The Company also has agreed to use its reasonable best efforts to maintain at least $8.0 million of debt, some of which must be property specific, for the same period to enable certain contributors to guarantee the debt in order to defer potential taxable gain they may incur if the Operating Partnership repays the existing debt.
	Legal Proceedings
	Although the Company is involved in legal proceedings arising in the ordinary course of business, as of December 31, 2013, the Company is not currently a party to any legal proceedings nor, to its knowledge, is any legal proceeding threatened against it that it believes would have a material adverse effect on its financial position, results of operations or liquidity.

Quarterly_Financial_Informatio

Quarterly Financial Information of the Parent Company (Notes) (Parent Company)	12 Months Ended
	Dec. 31, 2013
Parent Company	'
Quarterly Financial Information Disclosure [Line Items]	'
Quarterly Financial Information [Text Block]	'
	Quarterly Financial Information of the Parent Company (unaudited)
	The Company’s selected quarterly information for the years ended December 31, 2013 and 2012 (in thousands, except per share data) was as follows.
		2013 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	157,993		$	159,232		$	159,639		$	160,450
	Net income	10,576			4,136			15,037			17,458
	Net (income) / loss attributable to noncontrolling interests	(297		)	111			(234		)	(146		)
	Preferred stock dividends	—			—			—			(2,393		)
	Net income available to common stockholders	$	10,279		$	4,247		$	14,803		$	8,388
	Net income per share available to common stockholders - basic and diluted	$	0.05		$	0.02		$	0.08		$	0.05
		2012 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	138,771		$	134,537		$	124,848		$	120,012
	Income / (loss) from continuing operations	8,260			6,455			(5,283		)	6,702
	Income / (loss) from discontinued operations	—			—			49			(4,420		)
	Net income / (loss)	8,260			6,455			(5,234		)	2,282
	Net (income) / loss attributable to noncontrolling interests	(93		)	(46		)	172			30
	Preferred stock dividends	(3,651		)	(3,651		)	(3,651		)	(3,651		)
	Net income / (loss) available to common stockholders	$	4,516		$	2,758		$	(8,713	)	$	(1,339	)
	Income / (loss) from continuing operations per share available to common stockholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	0.02
	Net income / (loss) per share available to common stockholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	(0.01	)
	-1	The sum of quarterly financial data may vary from the annual data due to rounding.

Quarterly_Financial_Informatio1

Quarterly Financial Information of the Operating Partnership Quarterly Financial Information of the Operating Partnership (BIOMED REALTY, L.P.)	12 Months Ended
	Dec. 31, 2013
BIOMED REALTY, L.P.	'
Quarterly Financial Information Disclosure [Line Items]	'
Quarterly Financial Information [Text Block]	'
	Quarterly Financial Information of the Operating Partnership (unaudited)
	The Company’s selected quarterly information for the years ended December 31, 2013 and 2012 (in thousands, except per share data) was as follows.
		2013 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	157,993		$	159,232		$	159,639		$	160,450
	Net income	10,576			4,136			15,037			17,458
	Net (income) / loss attributable to noncontrolling interests	(12		)	229			29			8
	Preferred unit distributions	—			—			—			(2,393		)
	Net income available to unitholders	$	10,564		$	4,365		$	15,066		$	8,542
	Net income per unit available to unitholders - basic and diluted	$	0.05		$	0.02		$	0.08		$	0.05
		2012 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	138,771		$	134,537		$	124,848		$	120,012
	Income / (loss) from continuing operations	8,260			6,455			(5,283		)	6,702
	Income / (loss) from discontinued operations	—			—			49			(4,420		)
	Net income / (loss)	8,260			6,455			(5,234		)	2,282
	Net (income) / loss attributable to noncontrolling interests	(7		)	7			6			4
	Preferred unit distributions	(3,651		)	(3,651		)	(3,651		)	(3,651		)
	Net income / (loss) available to unitholders	$	4,602		$	2,811		$	(8,879	)	$	(1,365	)
	Income / (loss) from continuing operations per unit available to unitholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	0.02
	Net income / (loss) per unit available to unitholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	(0.01	)
	-1	The sum of quarterly financial data may vary from the annual data due to rounding.

Schedule_III_Schedule_III_Note

Schedule III Schedule III (Notes)	12 Months Ended
	Dec. 31, 2012
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract]	'
SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Text Block]	'
	A reconciliation of historical cost and related accumulated depreciation is as follows (in thousands):
		Year Ended December 31,
		2013			2012			2011
	Investment in real estate:
	Balance at beginning of year	$	4,923,166		$	4,402,720		$	3,878,092
	Property acquisitions	835,599			395,560			409,425
	Property sales	(4,155		)	(33,048		)	—
	Improvements	244,719			157,934			115,203
	Balance at end of year	$	6,003,480		$	4,923,166		$	4,402,720
	Accumulated Depreciation:
	Balance at beginning of year	$	(603,450	)	$	(452,474	)	$	(341,978	)
	Depreciation expense	(182,129		)	(152,506		)	(110,496		)
	Property sales	1,374			1,530			—
	Balance at end of year	$	(785,578	)	$	(603,450	)	$	(452,474	)

Basis_of_Presentation_and_Summ1

Basis of Presentation and Summary of Significant Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Principles of Consolidation	'
	Principles of Consolidation
	The consolidated financial statements include the accounts of the Company, its wholly-owned subsidiaries, partnerships and limited liability companies it controls, and variable interest entities (“VIEs”) for which the Company has determined itself to be the primary beneficiary. All material intercompany transactions and balances have been eliminated. The Company consolidates entities the Company controls and records a noncontrolling interest for the portions not owned by the Company. Control is determined, where applicable, by the sufficiency of equity invested and the rights of the equity holders, and by the ownership of a majority of the voting interests, with consideration given to the existence of approval or veto rights granted to the minority stockholder. If the minority stockholder holds substantive participating rights, it overcomes the presumption of control by the majority voting interest holder. In contrast, if the minority stockholder simply holds protective rights (such as consent rights over certain actions), it does not overcome the presumption of control by the majority voting interest holder.
	Assets and liabilities of subsidiaries outside the United States with non-U.S. dollar functional currencies are translated into U.S. dollars using exchange rates as of the balance sheet dates. Income and expenses are translated using the average exchange rates for the reporting period. Foreign currency translation adjustments are recorded as a component of other comprehensive income. For the years ended December 31, 2013 and 2012, total revenues from properties outside the United States were $18.2 million and $10.3 million, respectively, which represented 2.9% and 2.0% of the Company's total revenues during the respective periods. The Company’s net investments in properties outside the United States were $190.2 million and $188.8 million at December 31, 2013 and December 31, 2012, respectively.
Investments in Partnerships and Limited Liability Companies	'
	Investments in Partnerships and Limited Liability Companies
	The Company evaluates its investments in limited liability companies and partnerships to determine whether such entities may be a VIE, and, if a VIE, whether the Company is the primary beneficiary. Generally, an entity is determined to be a VIE when either (1) the equity investors (if any) lack one or more of the essential characteristics of a controlling financial interest, (2) the equity investment at risk is insufficient to finance that entity's activities without additional subordinated financial support or (3) the equity investors have voting rights that are not proportionate to their economic interests and the activities of the entity involve or are conducted on behalf of an investor with a disproportionately small voting interest. The primary beneficiary is the entity that has both (1) the power to direct matters that most significantly impact the VIE's economic performance and (2) the obligation to absorb losses or the right to receive benefits of the VIE that could potentially be significant to the VIE. The Company considers a variety of factors in identifying the entity that holds the power to direct matters that most significantly impact the VIE's economic performance including, but not limited to, the ability to direct financing, leasing, construction and other operating decisions and activities. In addition, the Company considers the rights of other investors to participate in policy making decisions, to replace or remove the manager and to liquidate or sell the entity. The obligation to absorb losses and the right to receive benefits when a reporting entity is affiliated with a VIE must be based on ownership, contractual, and/or other pecuniary interests in that VIE. The Company has determined that it is the primary beneficiary in five VIEs (excluding certain VIEs through its ownership of Wexford), consisting of single-tenant properties in which the tenant has a fixed-price purchase option, which are consolidated and reflected in the accompanying consolidated financial statements. Selected financial data of the VIEs at December 31, 2013 and December 31, 2012 consist of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Investment in real estate, net	$	336,832		$	334,331
	Total assets	375,443			369,460
	Total debt	143,067			144,889
	Total liabilities	154,953			149,336
	If the foregoing conditions do not apply, the Company considers whether a general partner or managing member controls a limited partnership or limited liability company. The general partner in a limited partnership or managing member in a limited liability company is presumed to control that limited partnership or limited liability company. The presumption may be overcome if the limited partners or members have either (1) the substantive ability to dissolve the limited partnership or limited liability company or otherwise remove the general partner or managing member without cause or (2) substantive participating rights, which provide the limited partners or members with the ability to effectively participate in significant decisions that would be expected to be made in the ordinary course of the limited partnership’s or limited liability company’s business and thereby preclude the general partner or managing member from exercising unilateral control over the partnership or company. If these criteria are met and the Company is the general partner or the managing member, as applicable, the consolidation of the partnership or limited liability company is required.
	Except for investments that are consolidated, the Company accounts for investments in entities over which it exercises significant influence, but does not control, under the equity method of accounting. These investments are recorded initially at cost and subsequently adjusted for equity in earnings and cash contributions and distributions. Under the equity method of accounting, the Company’s net equity in the investment is reflected in the consolidated balance sheets and its share of net income or loss is included in the Company’s consolidated statements of income.
	On a periodic basis, management assesses whether there are any indicators that the carrying value of the Company’s investments in unconsolidated partnerships or limited liability companies may be impaired on a more than temporary basis. An investment is impaired only if management’s estimate of the fair-value of the investment is less than the carrying value of the investment on a more than temporary basis. To the extent impairment has occurred, the loss is measured as the excess of the carrying value of the investment over the fair-value of the investment. Management does not believe that the carrying value of any of the Company’s unconsolidated investments in partnerships or limited liability companies was impaired as of December 31, 2013.
	The Company is also a party to certain VIEs through its ownership of Wexford, which are described in further detail in Note 11.
Investments in Real Estate, Net	'
	Investments in Real Estate, Net
	Investments in real estate are carried at depreciated cost. Depreciation and amortization are recorded on a straight-line basis over the estimated useful lives of the assets as follows:
	Buildings and improvements	Remaining useful life, not to exceed 40 years
	Tenant improvements	Shorter of the useful lives or the terms of the related leases
	Furniture, fixtures, and equipment (other assets)	Three to five years
	Acquired in-place leases	Non-cancelable term of the related lease
	Acquired management agreements	Non-cancelable term of the related agreement
	Investments in real estate, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Land	$	713,955		$	702,993
	Land under development	119,325			48,744
	Buildings and improvements	4,854,175			4,028,089
	Construction in progress	316,025			143,340
		6,003,480			4,923,166
	Accumulated depreciation	(785,578		)	(603,450		)
		$	5,217,902		$	4,319,716
	Purchase accounting is applied to the assets and liabilities of real estate properties in which the Company acquires a controlling interest or a partial interest. The fair-value of tangible assets of an acquired property (which includes land, buildings, and improvements) is determined by valuing the property as if it were vacant, and the “as-if-vacant” value is then allocated to land, buildings and improvements based on management’s determination of the fair-value of these assets. Factors considered by the Company in performing these analyses include an estimate of the carrying costs during the expected lease-up periods, 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 rental revenue during the expected lease-up periods based on current market demand. Upon the acquisition of a controlling interest of an investment in an unconsolidated partnership, such partnership is consolidated and a gain is recognized equal to the amount in which the fair-value of the noncontrolling interest in such partnership exceeded its carrying value at the time of obtaining control.
	The aggregate value of other acquired intangible assets consisting of acquired in-place leases and acquired management agreements (see deferred leasing costs below) are recorded based on a variety of considerations including, but not necessarily limited to: (1) the value associated with avoiding the cost of originating the acquired in-place leases (i.e. the market cost to execute a lease, including leasing commissions and legal fees, if any); (2) the value associated with lost revenue related to tenant reimbursable operating costs estimated to be incurred during the assumed lease-up period (i.e. real estate taxes and insurance); and (3) the value associated with lost rental revenue from existing leases during the assumed lease-up period (see discussion of the recognition of acquired above-market and below-market leases in Revenue Recognition section below). The fair-value assigned to the acquired management agreements are recorded at the present value (using a discount rate which reflects the risks associated with the management agreements acquired) of the acquired management agreements with certain tenants of the acquired properties. The Company has also considered the existence of a tenant relationship intangible asset, but has not historically allocated any value to tenant relationships apart from acquired in-place leases. The values of in-place leases and management agreements are amortized to expense over the remaining non-cancelable period of the respective leases or agreements. If a lease were to be terminated or if termination is determined to be likely (e.g., in the case of a tenant bankruptcy) prior to its contractual expiration, amortization of all unamortized amounts related to that lease would be accelerated and such amounts written off.
	Costs incurred in connection with the development or construction of properties and improvements are capitalized. Capitalized costs include pre-construction costs essential to the development of the property, development costs, construction costs, interest costs, real estate taxes, salaries and related costs and other direct costs incurred during the period of development. The Company capitalizes costs on land and buildings under development until construction is substantially complete and the property is held available for occupancy. Determination of when a development project is substantially complete and when capitalization must cease involves a degree of judgment. The Company considers a construction project as substantially complete and held available for occupancy upon the completion of landlord-owned tenant improvements or when the lessee takes possession of the unimproved space for construction of its own improvements, but no later than one year from cessation of major construction activity. The Company ceases capitalization on the portion substantially completed and occupied or held available for occupancy, and capitalizes only those costs associated with any remaining portion under construction. Interest costs capitalized for the years ended December 31, 2013, 2012 and 2011 were $14.2 million, $8.6 million and $7.6 million, respectively. Payroll costs capitalized for the years ended December 31, 2013, 2012 and 2011 were $3.6 million, $2.0 million and $1.3 million, respectively. Costs associated with acquisitions of businesses are charged to expense.
	Repair and maintenance costs are charged to expense as incurred and significant replacements and betterments are capitalized. Repairs and maintenance costs include all costs that do not extend the useful life of an asset or increase its operating efficiency. Significant replacement and betterments represent costs that extend an asset’s useful life or increase its operating efficiency.
Impairment of Long-Lived Assets and Long-Lived Assets to be Disposed	'
	Impairment of Long-Lived Assets and Long-Lived Assets to be Disposed
	The Company reviews long-lived assets and certain identifiable intangibles for impairment 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 its investments in long-lived assets. These assessments have a direct impact on the Company’s 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 to hold its properties over the long-term, 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, and such loss could be material.
	In April 2012, the Company completed the exchange of a property for another real estate operating property. As a result, the property disposed of was reclassified as a discontinued operation. This property was written down to its estimated fair-value of $28.0 million, less costs to sell, which resulted in an impairment loss of $4.6 million that is included in loss from discontinued operations for the year ended December 31, 2012. The parties to the exchange determined and agreed upon the fair-value of the property received in the transaction, which the Company considers to be a Level 2 input in the fair-value hierarchy. See Note 12 for discussion of discontinued operations.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	Cash and cash equivalents consist of highly liquid investments with original maturities of three months or less. The Company maintains its cash at insured financial institutions. The combined account balances at each institution periodically exceed FDIC insurance coverage, and, as a result, there is a concentration of credit risk related to amounts in excess of FDIC limits. The Company believes that the risk is not significant.
Deferred Leasing Costs, Net	'
	Deferred Leasing Costs, Net
	Leasing commissions and other direct costs associated with obtaining new or renewal leases are recorded at cost and amortized on a straight-line basis over the terms of the respective leases, with remaining terms ranging from less than one year to approximately 20 years as of December 31, 2013. Deferred leasing costs also include the net carrying value of acquired in-place leases and acquired management agreements.
	Deferred leasing costs, net at December 31, 2013 consisted of the following (in thousands):
		Balance at			Accumulated
		December 31, 2013			Amortization				Net
	Acquired in-place leases	$	365,753		$	(233,935	)		$	131,818
	Acquired management agreements	25,801			(20,053		)		5,748
	Deferred leasing and other direct costs	91,142			(30,641		)		60,501
		$	482,696		$	(284,629	)		$	198,067
	Deferred leasing costs, net at December 31, 2012 consisted of the following (in thousands):
		Balance at			Accumulated
		31-Dec-12			Amortization				Net
	Acquired in-place leases	$	303,521		$	(185,463	)		$	118,058
	Acquired management agreements	24,963			(15,242		)		9,721
	Deferred leasing and other direct costs	68,175			(23,591		)		44,584
		$	396,659		$	(224,296	)		$	172,363
	The estimated amortization expense for deferred leasing costs at December 31, 2013 was as follows (in thousands):
	2014	$	40,251
	2015	31,707
	2016	25,031
	2017	22,959
	2018	18,581
	Thereafter	59,538
	Total	$	198,067
Revenue Recognition, Operating Expenses and Lease Terminations	'
	Revenue Recognition, Operating Expenses and Lease Terminations
	The Company commences revenue recognition on its leases based on a number of factors. In most cases, revenue recognition under a lease begins when the lessee takes possession of or controls the physical use of the leased asset. Generally, this occurs on the lease commencement date. In determining what constitutes the leased asset, the Company evaluates whether the Company or the lessee is the owner, for accounting purposes, of the tenant improvements. If the Company is the owner, for accounting purposes, of the tenant improvements, then the leased asset is the finished space and revenue recognition begins when the lessee takes possession of the finished space, typically when the improvements are substantially complete. If the Company concludes that it is not the owner, for accounting purposes, of the tenant improvements (the lessee is the owner), then the leased asset is the unimproved space and any tenant improvement allowances funded under the lease are treated as lease incentives, which reduce revenue recognized on a straight-line basis over the remaining non-cancelable term of the respective lease. In these circumstances, the Company begins revenue recognition when the lessee takes possession of the unimproved space for the lessee to construct improvements. The determination of who is the owner, for accounting purposes, of the tenant improvements determines the nature of the leased asset and when revenue recognition under a lease begins. The Company considers a number of different factors to evaluate whether it or the lessee is the owner of the tenant improvements for accounting purposes. These factors include:
	•	whether the lease stipulates how and on what a tenant improvement allowance may be spent;
	•	whether the tenant or landlord retain legal title to the improvements;
	•	the uniqueness of the improvements;
	•	the expected economic life of the tenant improvements relative to the length of the lease;
	•	the responsible party for construction cost overruns; and
	•	who constructs or directs the construction of the improvements.
	The determination of who owns the tenant improvements, for accounting purposes, is subject to significant judgment. In making that determination, the Company considers all of the above factors. However, no one factor is determinative in reaching a conclusion.
	All leases are classified as operating leases and minimum rents are recognized on a straight-line basis over the term of the related lease. The excess of rents recognized over amounts contractually due pursuant to the underlying leases are included in accrued straight-line rents on the accompanying consolidated balance sheets and contractually due but unpaid rents are included in accounts receivable. Existing leases at acquired properties are reviewed at the time of acquisition to determine if contractual rents are above or below current market rents for the acquired property. An identifiable lease intangible asset or liability is recorded based on the present value (using a discount rate that reflects the risks associated with the acquired leases) of the difference between (1) the contractual amounts to be paid pursuant to the in-place leases and (2) the Company’s estimate of the fair market lease rates for the corresponding in-place leases at acquisition, measured over a period equal to the remaining non-cancelable term of the leases and any fixed rate renewal periods (based on the Company’s assessment of the likelihood that the renewal periods will be exercised). The capitalized above-market lease values are amortized as a reduction of rental revenue on a straight-line basis over the remaining non-cancelable terms of the respective leases. The capitalized below-market lease values are amortized as an increase to rental revenue on a straight-line basis over the remaining non-cancelable terms of the respective leases and any fixed-rate renewal periods, if applicable. If a tenant vacates its space prior to the contractual termination of the lease and no rental payments are being made on the lease, any unamortized balance of the related intangible will be written off.
	The impact of the straight-line rent revenue, acquired above and below market lease revenue, and lease incentive revenue consisted of the following (in thousands):
		Years Ended December 31,
		2013			2012				2011
	Straight-line rent revenue	$	23,136		$	23,288			$	25,243
	Acquired above-market lease revenue	(11,913		)	(9,977		)		(9,607		)
	Acquired below-market lease revenue	4,325			1,684				1,453
	Lease incentive revenue	(2,295		)	(2,969		)		(2,246		)
	Net increase in revenue	$	13,253		$	12,026			$	14,843
	Total estimated minimum rents under non-cancelable operating tenant leases in effect at December 31, 2013 were as follows (in thousands):
	2014	$	455,359
	2015	450,564
	2016	424,331
	2017	400,787
	2018	342,864
	Thereafter	2,037,341
	Total	$	4,111,246
	The estimated amortization for acquired above- and below-market lease revenue and lease incentive revenue at December 31, 2013 was as follows (in thousands):
		2014			2015				2016				2017				2018				Thereafter			Total
	Amortization of:
	Acquired above-market leases	$	(4,457	)	$	(1,942	)		$	(1,317	)		$	(1,196	)		$	(1,112	)		$	(5,804	)	$	(15,828	)
	Acquired below-market leases	5,262			3,721				3,487				3,435				3,427				18,789			38,121
	Lease incentive	(2,232		)	(2,225		)		(2,152		)		(1,728		)		(1,329		)		(9,973		)	(19,639		)
	Rental operations expenses, consisting of real estate taxes, insurance and common area maintenance costs, are subject to recovery from tenants under the terms of lease agreements. Amounts recovered are dependent on several factors, including occupancy and lease terms. Revenues are recognized in the period the expenses are incurred. The reimbursements are recorded in revenues as tenant recoveries, and the expenses are recorded in rental operations expenses, as the Company is generally the primary obligor with respect to purchasing goods and services from third-party suppliers, has discretion in selecting the supplier and bears the credit risk.
	On an ongoing basis, the Company evaluates the recoverability of tenant balances, including rents receivable, straight-line rents receivable, tenant improvements, deferred leasing costs and any acquisition intangibles. Factors considered by the Company as part of this evaluation include, among other things, the financial strength of the tenant and any guarantors, a review of publicly filed documents and analyst research reports, a review of the tenant's cash balance and estimated cash "burn" rate if the tenant's cash flow from operations is negative, and the tenant's payment history. When it is determined that the recoverability of tenant balances is not probable, an allowance for expected losses related to tenant receivables, including straight-line rents receivable is recorded as a charge to earnings. Upon the termination of a lease, the amortization of tenant improvements, deferred leasing costs and acquisition intangible assets and liabilities is accelerated to the expected termination date as a charge to their respective line items and tenant receivables are written off as a reduction of the allowance in the period in which the balance is deemed to be no longer collectible. For financial reporting purposes, a lease is treated as terminated upon a tenant filing for bankruptcy, when a space is abandoned and a tenant ceases rent payments, or when other circumstances indicate that termination of a tenant’s lease is probable (e.g., eviction). Lease termination fees are recognized in other income when the related leases are canceled, the amounts to be received are fixed and determinable and collectability is assured, and when the Company has no continuing obligation to provide services to such former tenants.
Allowance For Doubtful Accounts	'
	Allowance for Doubtful Accounts
	The Company maintains an allowance for doubtful accounts for estimated losses resulting from the inability of tenants to make required rent and tenant recovery payments or defaults. The Company maintains an allowance for accrued straight-line rents. The determination of this allowance is based on the tenants’ payment history and current credit status. Bad debt expense included in rental operations expenses was approximately $931,000, $1.7 million and $2.3 million for the years ended December 31, 2013, 2012 and 2011, respectively. The Company’s allowance for doubtful accounts included in accounts receivable, net and accrued straight line rent, net was approximately $2.3 million, $4.2 million and $2.9 million as of December 31, 2013, 2012 and 2011, respectively.
Investments	'
	Investments
	The Company, through its Operating Partnership, holds equity investments in certain publicly-traded companies and privately-held companies primarily involved in the life science industry. The Company may accept equity investments from tenants in lieu of cash rents, as prepaid rent pursuant to the execution of a lease, or as additional consideration for a lease termination. The Company does not acquire investments for trading purposes and, as a result, all of the Company’s investments in publicly-traded companies are considered “available-for-sale” and are recorded at fair-value. Changes in the fair-value of investments classified as available-for-sale are recorded in comprehensive income. The fair-value of the Company’s equity investments in publicly-traded companies is determined based upon the closing trading price of the equity security as of the balance sheet date, with unrealized gains and losses shown as a separate component of equity. Investments in privately-held companies are generally accounted for under the cost method, because the Company does not influence any operating or financial policies of the companies in which it invests. The classification of investments is determined at the time each investment is made, and such determination is reevaluated at each balance sheet date. The cost of investments sold is determined by the specific identification method, with net realized gains and losses included in other income. For all investments, if a decline in the fair-value of an investment below its carrying value is determined to be other-than-temporary, such investment is written down to its estimated fair-value with a non-cash charge to earnings. The factors that the Company considers in making these assessments include, but are not limited to, market prices, market conditions, available financing, prospects for favorable or unfavorable clinical trial results, new product initiatives and new collaborative agreements.
	Investments in equity securities, which are included in other assets on the accompanying consolidated balance sheets, consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Available-for-sale securities, historical cost	$	8,543		$	275
	Unrealized gain, net	11,023			115
	Available-for-sale securities, fair-value (1)	19,566			390
	Privately-held securities, cost basis	18,485			12,280
	Total equity securities	$	38,051		$	12,670
	-1	Determination of fair-value is classified as Level 1 in the fair-value hierarchy based on the use of quoted prices in active markets.
	The Company holds investments in available-for-sale securities of certain publicly-traded companies. Certain of these investments have fair-values less than the Company’s cost basis, net of previous other-than-temporary impairment in these securities due to decreases in their respective stock prices during the year ended December 31, 2013. However, management has the intent and ability to retain the investments for a period of time sufficient to allow for an anticipated recovery in their market value. Management will continue to periodically evaluate whether any investment, the fair-value of which is less than the Company’s cost basis, should be considered other-than-temporarily impaired. If other-than-temporary impairment is considered to exist, the related unrealized loss will be reclassified from accumulated other comprehensive loss and recorded as a reduction of net income.
	The Company also holds investments in securities of certain privately-held companies and funds, which are recorded at cost basis due to the Company’s lack of control or significant influence over such companies and funds.
	During the year ended December 31, 2013, the Company recorded a $2.8 million impairment charge, which is included in other expense in the consolidated statements of operations. The impairment charge related to the Company’s investment in a privately-held company, comprising a $2.0 million cost basis equity investment and $825,000 related to notes receivable that were included in other assets on the consolidated balance sheets. Other than this investment there were no identified events or changes in circumstances that may have a significant adverse effect on the carrying value of the Company’s cost basis investments and therefore, no evaluation of impairment was performed during the year ended December 31, 2013 on the Company’s remaining cost basis investments.
Share-based Payments	'
	Share-Based Payments
	All share-based payments to employees are recognized in the consolidated statement of operations based on their fair-value. Through December 31, 2013, the Company had awarded restricted stock of the Parent Company and LTIP unit grants of the Operating Partnership under its incentive award plan, both of which are valued based on the closing market price of the underlying common stock on the date of grant, and had not granted any stock options. During the years ended December 31, 2013 and 2012, the Parent Company awarded performance units (the “Performance Units”) to certain of its executive officers. Each Performance Unit represents a contingent right to receive one share of the Parent Company’s common stock if vesting conditions are satisfied. The grant date fair-value of the Performance Units was estimated using a Monte Carlo simulation which considered the likelihood of achieving the vesting conditions (see Note 13 for further information on the fair-value of the Performance Units). The fair-value of all share-based payments is amortized to general and administrative expense and rental operations expense over the relevant service period, adjusted for anticipated forfeitures.
Assets and Liabilities Measured at Fair-Value	'
	Assets and Liabilities Measured at Fair-Value
	The Company measures financial instruments and other items at fair-value where required under GAAP, but has elected not to measure any additional financial instruments and other items at fair-value as permitted under fair-value option accounting guidance.
	Fair-value measurement is determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair-value measurements, there is a fair-value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the hierarchy).
	Level 1 inputs utilize 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. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. 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 Company has used interest rate swaps to manage its interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves. The fair-values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair-value measurements. In adjusting the fair-value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees.
	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. However, as of December 31, 2013, the Company has determined that the impact of the credit valuation adjustments on the overall valuation of its derivative positions is not significant. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair-value hierarchy (see Note 9).
	The valuation of the Company’s investments in publicly-traded companies utilizes observable market-based inputs, based on the closing trading price of securities as of the balance sheet date, therefore, the Company has determined that valuations of available-for-sale securities are classified in Level 1 of the fair-value hierarchy.
	No other assets or liabilities are measured at fair-value on a recurring basis, or have been measured at fair-value on a non-recurring basis subsequent to initial recognition, in the accompanying consolidated balance sheets as of December 31, 2013
Derivative Instruments	'
	Derivative Instruments
	The Company records all derivatives on the consolidated balance sheets at fair-value. In determining the fair-value of its derivatives, the Company considers the credit risk of its counterparties and the Company. These counterparties are generally larger financial institutions engaged in providing a variety of financial services. These institutions generally face similar risks regarding adverse changes in market and economic conditions, including, but not limited to, fluctuations in interest rates, exchange rates, equity and commodity prices and credit spreads. The ongoing disruptions in the financial markets have heightened the risks to these institutions. While management believes that its counterparties will meet their obligations under the derivative contracts, it is possible that defaults may occur.
	The accounting for changes in the fair-value of derivatives depends on the intended use of the derivative, whether the Company has elected to designate a derivative in a hedging relationship and apply hedge accounting and whether the hedging relationship has satisfied the criteria necessary to apply hedge accounting. Derivatives designated and qualifying as a hedge of the exposure to changes in the fair-value of an asset, liability, or firm commitment attributable to a particular risk, such as interest rate risk, are considered fair-value hedges. Derivatives designated and qualifying as a hedge of the exposure to variability in expected future cash flows, or other types of forecasted transactions, are considered cash flow hedges. Derivatives may also be designated as hedges of the foreign currency exposure of a net investment in a foreign operation. Hedge accounting generally provides for the matching of the timing of gain or loss recognition on the hedging instrument with the recognition of the changes in the fair-value of the hedged asset or liability that are attributable to the hedged risk in a fair-value hedge or the earnings effect of the hedged forecasted transactions in a cash flow hedge. The Company may enter into derivative contracts that are intended to economically hedge certain of its risks, even though hedge accounting does not apply or the Company elects not to apply hedge accounting.
	For derivatives designated as cash flow hedges, the effective portion of changes in the fair-value of the derivative is initially reported in other comprehensive income (outside of earnings) and subsequently reclassified to earnings in the period in which the hedged transaction affects earnings. If charges relating to the hedged transaction are being deferred pursuant to redevelopment or development activities, the effective portion of changes in the fair-value of the derivative are also deferred in accumulated other comprehensive income on the consolidated balance sheet, and are amortized to the income statement once the deferred charges from the hedged transaction begin again to affect earnings. The ineffective portion of changes in the fair-value of the derivative is recognized directly in earnings. The Company assesses the effectiveness of each hedging relationship by comparing the changes in cash flows of the derivative hedging instrument with the changes in cash flows of the designated hedged item or transaction. For derivatives that are not classified as hedges, changes in the fair-value of the derivative are recognized directly in earnings in the period in which the change occurs.
	The Company is exposed to certain risks arising from both its business operations and economic conditions. The Company principally manages its exposures to a wide variety of business and operational risks through management of its core business activities. The Company manages economic risks, including interest rate, liquidity, and credit risk primarily by managing the amount, sources, and duration of its debt funding and the use of derivative financial instruments. Specifically, the Company enters into derivative financial instruments to manage exposures that arise from business activities that result in the receipt or payment of future known or expected cash amounts, the value of which are determined by interest rates. The Company’s derivative financial instruments are used to manage differences in the amount, timing, and duration of the Company’s known or expected cash receipts and its known or expected cash payments principally related to the Company’s investments and borrowings.
	The Company’s primary objective in using derivatives is to add stability to interest expense and to manage its exposure to interest rate movements or other identified risks. To accomplish this objective, the Company primarily uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying principal amount. During the years ended December 31, 2013, 2012 and 2011, such derivatives were used to hedge the variable cash flows associated with existing variable-rate debt and future variability in the interest-related cash flows from forecasted issuances of debt (see Note 9). The Company formally documents the hedging relationships for all derivative instruments, has historically accounted for its interest rate swap agreements as cash flow hedges, and does not use derivatives for trading or speculative purposes.
Equity Offering Costs	'
	Equity Offering Costs
	Underwriting commissions and offering costs are reflected as a reduction of proceeds.
Income Taxes of the Parent Company / Operating Partnership	'
	Income Taxes of the Parent Company
	The Parent Company has elected to be taxed as a REIT under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended. The Parent Company believes it has qualified and continues to qualify as a REIT. A REIT is generally not subject to federal income tax on that portion of its taxable income that is distributed to its stockholders. Accordingly, no provision has been made for federal income taxes in the accompanying consolidated financial statements. REITs are subject to a number of organizational and operational requirements. If the Parent Company fails to qualify as a REIT in any taxable year, the Parent Company will be subject to federal income tax (including any applicable alternative minimum tax) and, in most of the states, state income tax on its taxable income at regular corporate tax rates. The Parent Company is subject to certain state and local taxes.
	Income Taxes of the Operating Partnership
	As a partnership, the allocated share of income of the Operating Partnership is included in the income tax returns of the general and limited partners. Accordingly, no accounting for income taxes is required in the accompanying consolidated financial statements. The Operating Partnership may be subject to certain state or local taxes on its income and property.
	The Operating Partnership has formed certain taxable REIT subsidiaries (each a “TRS”) on behalf of the Parent Company. In general, each TRS may perform non-customary services for tenants, hold assets that the Parent Company cannot hold directly and, except for the operation or management of health care facilities or lodging facilities or the providing of any person, under a franchise, license or otherwise, rights to any brand name under which any lodging facility or health care facility is operated, may engage in any real estate or non-real estate related business. Each TRS is subject to corporate federal and state income taxes on its taxable income at regular corporate tax rates. There is no tax provision for any TRS for the periods presented in the accompanying consolidated statements of income due to net operating losses incurred. No tax benefits have been recorded since it is not considered more likely than not that the deferred tax asset related to the net operating loss carryforwards will be utilized.
Dividends and Distributions	'
	Dividends and Distributions
	Earnings and profits, which determine the taxability of dividends and distributions to stockholders, will differ from income reported for financial reporting purposes due to the difference for federal income tax purposes in the treatment of revenue recognition, compensation expense, and in the estimated useful lives of real estate assets used to compute depreciation.
	The income tax treatment for dividends was as follows:
		For the Years Ended December 31,
		2013						2012							2011
		Per Share			%			Per Share				%			Per Share				%
	Common stock:
	Ordinary income	$	0.94		100	%		$	0.63			74.12	%		$	0.44			57.14	%
	Capital gain	—			—			—				—			—				—
	Return of capital	—			—			0.22				25.88	%		0.33				42.86	%
	Total	$	0.94		100	%		$	0.85			100	%		$	0.77			100	%
	Preferred stock:
	Ordinary income	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%
	Capital gain	—			—			—				—			—				—
	Return of capital	—			—			—				—			—				—
	Total	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%
Construction Loan Receivable	'
	Construction Loan Receivable
	The Company has a $255.0 million interest in a $355.0 million construction loan secured by first priority mortgages on a 1.1 million square foot laboratory, office and retail development project located in Boston, Massachusetts, which is 95% leased to Vertex Pharmaceuticals Incorporated to serve as its new corporate headquarters.
	The construction loan matures on September 30, 2014, with two one -year extension options exercisable at the borrower’s election after paying the lenders an extension fee on the then-outstanding principal amount. The construction loan bears interest on the outstanding principal amount at a floating rate equal to the greater of (1) reserve adjusted LIBOR plus 550 basis points and (2) 6.5%. In addition, the borrower is required to pay a fee to the lenders based on a specified percentage of the average daily unfunded amount of the construction loan. The borrower may prepay the construction loan in part under certain circumstances, and may prepay the construction loan in full with prior notice and a prepayment fee to the lenders. As of December 31, 2013 and December 31, 2012, the Company had invested approximately $151.8 million and $21.7 million in the construction loan, respectively, which are included in other assets on the Company's consolidated balance sheet. The Company expects to have fully funded its obligation in the third quarter of 2014.
Lease Termination	'
	Lease Termination
	During the years ended December 31, 2013, 2012 and 2011, the Company recorded lease termination revenue, net of write-offs of lease intangibles, included in other revenue on the consolidated statement of operations of approximately $42.8 million, $3.5 million and $6.2 million, respectively. Lease termination revenue for the year ended December 31, 2013 related to the termination of a lease with Elan Corporation (“Elan”) at the Company’s Science Center at Oyster Point property for which Elan paid the Company $46.5 million, and the termination of a lease effective August 2013 with Merck at the Company's 320 Bent Street property for which Merck paid the Company $8.7 million in August 2012. Lease termination revenue for the year ended December 31, 2012 primarily related to the termination of the lease with Merck. Lease termination revenue for the year ended December 31, 2011 related to an early lease termination at one of our properties.
Management's Estimates	'
	Management’s Estimates
	Management has made a number of estimates and assumptions relating to the reporting of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reporting of revenue and expenses during the reporting period to prepare these consolidated financial statements in conformity with GAAP. The Company bases its estimates on historical experience and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and reported amounts of revenue and expenses that are not readily apparent from other sources. Actual results could differ from those estimates under different assumptions or conditions.

Basis_of_Presentation_and_Summ2

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Selected Financial Data of the VIEs	'
	Selected financial data of the VIEs at December 31, 2013 and December 31, 2012 consist of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Investment in real estate, net	$	336,832		$	334,331
	Total assets	375,443			369,460
	Total debt	143,067			144,889
	Total liabilities	154,953			149,336
	The Company has determined that certain special purpose entities owning properties under development are VIEs, since there is insufficient capital to finance the remaining development activities without further subordinated financial support. The Company has determined it is the primary beneficiary of these VIEs, because it has the authority to direct the activities which most significantly impact their economic performance. Selected financial data of the VIEs at December 31, 2013 consisted of the following (in thousands):
		December 31,
		2013
	Investment in real estate, net	$	177,901
	Total assets	198,968
	Total liabilities	60,197
Investments in Real Estate, Net	'
	Investments in real estate, net consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Land	$	713,955		$	702,993
	Land under development	119,325			48,744
	Buildings and improvements	4,854,175			4,028,089
	Construction in progress	316,025			143,340
		6,003,480			4,923,166
	Accumulated depreciation	(785,578		)	(603,450		)
		$	5,217,902		$	4,319,716
Deferred Leasing Costs, Net	'
	Deferred leasing costs, net at December 31, 2013 consisted of the following (in thousands):
		Balance at			Accumulated
		December 31, 2013			Amortization				Net
	Acquired in-place leases	$	365,753		$	(233,935	)		$	131,818
	Acquired management agreements	25,801			(20,053		)		5,748
	Deferred leasing and other direct costs	91,142			(30,641		)		60,501
		$	482,696		$	(284,629	)		$	198,067
	Deferred leasing costs, net at December 31, 2012 consisted of the following (in thousands):
		Balance at			Accumulated
		31-Dec-12			Amortization				Net
	Acquired in-place leases	$	303,521		$	(185,463	)		$	118,058
	Acquired management agreements	24,963			(15,242		)		9,721
	Deferred leasing and other direct costs	68,175			(23,591		)		44,584
		$	396,659		$	(224,296	)		$	172,363
Deferred Leasing Costs - Estimated Amortization Expense	'
	The estimated amortization expense for deferred leasing costs at December 31, 2013 was as follows (in thousands):
	2014	$	40,251
	2015	31,707
	2016	25,031
	2017	22,959
	2018	18,581
	Thereafter	59,538
	Total	$	198,067
Impact Of Straight Line Rent Revenue Acquired Above And Below Market Lease Revenue And Lease Incentive Revenue [Table Text Block]	'
	The impact of the straight-line rent revenue, acquired above and below market lease revenue, and lease incentive revenue consisted of the following (in thousands):
		Years Ended December 31,
		2013			2012				2011
	Straight-line rent revenue	$	23,136		$	23,288			$	25,243
	Acquired above-market lease revenue	(11,913		)	(9,977		)		(9,607		)
	Acquired below-market lease revenue	4,325			1,684				1,453
	Lease incentive revenue	(2,295		)	(2,969		)		(2,246		)
	Net increase in revenue	$	13,253		$	12,026			$	14,843
Estimated Minimum Rents	'
	Total estimated minimum rents under non-cancelable operating tenant leases in effect at December 31, 2013 were as follows (in thousands):
	2014	$	455,359
	2015	450,564
	2016	424,331
	2017	400,787
	2018	342,864
	Thereafter	2,037,341
	Total	$	4,111,246
Revenue Recognition - Estimated Amortization Expense	'
	The estimated amortization for acquired above- and below-market lease revenue and lease incentive revenue at December 31, 2013 was as follows (in thousands):
		2014			2015				2016				2017				2018				Thereafter			Total
	Amortization of:
	Acquired above-market leases	$	(4,457	)	$	(1,942	)		$	(1,317	)		$	(1,196	)		$	(1,112	)		$	(5,804	)	$	(15,828	)
	Acquired below-market leases	5,262			3,721				3,487				3,435				3,427				18,789			38,121
	Lease incentive	(2,232		)	(2,225		)		(2,152		)		(1,728		)		(1,329		)		(9,973		)	(19,639		)
Investments in Equity Securities	'
	Investments in equity securities, which are included in other assets on the accompanying consolidated balance sheets, consisted of the following (in thousands):
		December 31,			December 31,
		2013			2012
	Available-for-sale securities, historical cost	$	8,543		$	275
	Unrealized gain, net	11,023			115
	Available-for-sale securities, fair-value (1)	19,566			390
	Privately-held securities, cost basis	18,485			12,280
	Total equity securities	$	38,051		$	12,670
	-1	Determination of fair-value is classified as Level 1 in the fair-value hierarchy based on the use of quoted prices in active markets.
Income Tax Treatment for Dividends	'
	The income tax treatment for dividends was as follows:
		For the Years Ended December 31,
		2013						2012							2011
		Per Share			%			Per Share				%			Per Share				%
	Common stock:
	Ordinary income	$	0.94		100	%		$	0.63			74.12	%		$	0.44			57.14	%
	Capital gain	—			—			—				—			—				—
	Return of capital	—			—			0.22				25.88	%		0.33				42.86	%
	Total	$	0.94		100	%		$	0.85			100	%		$	0.77			100	%
	Preferred stock:
	Ordinary income	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%
	Capital gain	—			—			—				—			—				—
	Return of capital	—			—			—				—			—				—
	Total	$	0.76		100	%		$	1.84			100	%		$	1.84			100	%

Equity_of_the_Parent_Company_T

Equity of the Parent Company (Tables)	12 Months Ended
	Dec. 31, 2013
Equity of the Parent Company	'
Dividends and Distributions	'
	The following table lists the dividends and distributions declared by the Parent Company and the Operating Partnership during the year ended December 31, 2013:
	Declaration Date		Securities Class		Amount Per				Period Covered		Dividend and		Dividend and
					Share/Unit						Distribution		Distribution Amount
											Payable Date
													(In thousands)
	March 15, 2013		Common stock and OP units		$	0.235			January 1, 2013 to March 31, 2013		April 15, 2013		$	40,413
	June 14, 2013		Common stock and OP units		$	0.235			April 1, 2013 to June 30, 2013		July 15, 2013		$	46,381
	September 16, 2013		Common stock and OP units		$	0.235			July 1, 2013 to September 30, 2013		October 15, 2013		$	46,418
	December 12, 2013		Common stock and OP units		$	0.25			October 1, 2013 to December 31, 2013		January 15, 2014		$	49,383
	Total 2013 dividends and distributions declared through December 31, 2013 (in thousands):
	Common stock and OP units	$	182,595
	Series A preferred stock/units (1)	2,393
		$	184,988
	-1	On March 15, 2013, the Parent Company redeemed all 7,920,000 outstanding shares of its Series A preferred stock for approximately $198.0 million, or $25.00 per share, net of accrued dividends of approximately $2.4 million, or $0.30217 per share.
Changes in Accumulated Other Comprehensive Loss by Component	'
	Changes in Accumulated Other Comprehensive Loss by Component
		Foreign currency translation adjustments				Unrealized gains on available- for-sale securities				Gain / (loss) on derivative instruments				Total
	Balance at December 31, 2012	$	3,611			$	115			$	(56,803	)		$	(53,077	)
	Other comprehensive income before reclassifications	395				9,071				3,497				12,963
	Amounts reclassified from accumulated other comprehensive income (1)	—				1,836				9,451				11,287
	Net other comprehensive income	395				10,907				12,948				24,250
	Net other comprehensive income allocable to noncontrolling interest	$	—			$	(1,836	)		$	—			$	(1,836	)
	Balance as of December 31, 2013	$	4,006			$	9,186			$	(43,855	)		$	(30,663	)
	-1	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.
Vested Ownership Interests	'
	The following table shows the vested ownership interests in the Operating Partnership:
		December 31, 2013						December 31, 2012
		Operating Partnership Units and LTIP Units			Percentage of Total			Operating Partnership Units and LTIP Units			Percentage of Total
	BioMed Realty Trust	190,676,428			97.3	%		152,853,368			98.1	%
	Noncontrolling interest consisting of:
	Operating partnership and LTIP units held by employees and related parties	2,656,388			1.4	%		2,339,314			1.5	%
	Operating partnership and LTIP units held by third parties	2,627,145			1.3	%		565,051			0.4	%
	Total	195,959,961			100	%		155,757,733			100	%
Parent Company	'
Equity of the Parent Company	'
Changes in Accumulated Other Comprehensive Loss by Component	'
	Changes in Accumulated Other Comprehensive Loss by Component
		Foreign currency translation adjustments				Unrealized gains on available-for-sale securities				Gain / (loss) on derivative instruments				Total
	Balance at December 31, 2012	$	3,543			$	114			$	(58,382	)		$	(54,725	)
	Other comprehensive income before reclassifications	395				9,071				3,497				12,963
	Amounts reclassified from accumulated other comprehensive income (1)	—				1,836				9,451				11,287
	Net other comprehensive income	395				10,907				12,948				24,250
	Net other comprehensive income allocable to noncontrolling interests	(33		)		(2,083		)		(332		)		(2,448		)
	Balance as of December 31, 2013	$	3,905			$	8,938			$	(45,766	)		$	(32,923	)
	-1	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.

Capital_of_the_Operating_Partn1

Capital of the Operating Partnership Capital of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2013
Statement of Partners' Capital [Abstract]	'
Changes in Accumulated Other Comprehensive Loss by Component	'
	Changes in Accumulated Other Comprehensive Loss by Component
		Foreign currency translation adjustments		Unrealized gains on available- for-sale securities			Gain / (loss) on derivative instruments			Total
	Balance at December 31, 2012	$	3,611	$	115		$	(56,803	)	$	(53,077	)
	Other comprehensive income before reclassifications	395		9,071			3,497			12,963
	Amounts reclassified from accumulated other comprehensive income (1)	—		1,836			9,451			11,287
	Net other comprehensive income	395		10,907			12,948			24,250
	Net other comprehensive income allocable to noncontrolling interest	$	—	$	(1,836	)	$	—		$	(1,836	)
	Balance as of December 31, 2013	$	4,006	$	9,186		$	(43,855	)	$	(30,663	)
	-1	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.

Debt_Tables

Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Summary of the Operating Partnership's Outstanding Consolidated Debt	'
	The following is a summary of the Operating Partnership’s outstanding consolidated debt as of December 31, 2013 and December 31, 2012 (dollars in thousands):
		Stated Interest Rate		Effective Interest Rate		Principal Balance
						December 31,			December 31,			Maturity Date
						2013			2012
	Mortgage Notes Payable
	9900 Belward Campus Drive	5.64	%	3.99	%	$	10,631		$	10,767		July 1, 2017
	9901 Belward Campus Drive	5.64	%	3.99	%	13,091			13,260			July 1, 2017
	Center for Life Science | Boston	7.75	%	7.75	%	334,447			338,447			June 30, 2014
	4320 Forest Park Avenue (1)	4	%	2.7	%	21,000			—			June 30, 2015
	Hershey Center for Applied Research (1)	6.15	%	4.71	%	13,449			—			May 5, 2027
	500 Kendall Street (Kendall D)	6.38	%	5.45	%	57,927			60,164			December 1, 2018
	Shady Grove Road	5.97	%	5.97	%	143,067			144,889			September 1, 2016
	University of Maryland BioPark I (1)	5.93	%	4.69	%	16,752			—			May 15, 2025
	University of Maryland BioPark II (1)	5.2	%	4.33	%	62,946			—			September 5, 2021
	University of Maryland BioPark Garage (1)	5.2	%	4.33	%	4,738			—			September 1, 2021
	University of Miami Life Science & Technology Park (1)	4	%	2.89	%	20,000			—			February 1, 2016
						698,048			567,527
	Unamortized premiums					11,276			4,125
	Mortgage notes payable, net					709,324			571,652
	Exchangeable Senior Notes	3.75	%	3.75	%	180,000			180,000			January 15, 2030
	Notes due 2016	3.85	%	3.99	%	400,000			400,000			April 15, 2016
	Notes due 2020	6.13	%	6.27	%	250,000			250,000			April 15, 2020
	Notes due 2022	4.25	%	4.36	%	250,000			250,000			July 15, 2022
						900,000			900,000
	Unamortized discounts					(4,917		)	(5,823		)
	Unsecured senior notes, net					895,083			894,177
	Term Loan due 2017 - U.S. dollar (2)	1.82	%	2.63	%	243,596			243,596			March 30, 2017
	Term Loan due 2017 - GBP (2)	2.14	%	2.39	%	165,190			161,860			March 30, 2017
	Term Loan due 2018 (3)	1.67	%	1.97	%	350,000			—			March 24, 2018
	Unsecured senior term loans					758,786			405,456
	Unsecured line of credit (3) (4)	1.46	%	1.46	%	128,000			118,000			March 24, 2018
	Total consolidated debt					$	2,671,193		$	2,169,285
	-1	Mortgage notes which were assumed on May 31, 2013 in connection with the Company’s merger with Wexford.
	-2	In August 2012, the Operating Partnership converted approximately $156.4 million of outstanding borrowings into British pounds sterling (“GBP”) equal to £100.0 million, which was designated as a net investment hedge to mitigate the risk of fluctuations in foreign currency exchange rates. The principal balance represents the U.S. dollar amount based on the exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively. The effective interest rate includes the impact of interest rate swap agreements (see Note 9 for further discussion of interest rate swap agreements).
	-3	In September 2013, the Operating Partnership amended and restated its unsecured credit agreement, providing for aggregate borrowing of up to $1.25 billion, consisting of an unsecured line of credit of $900.0 million and a term loan of $350.0 million (the Term Loan due 2018). In connection with the amendment and restatement of the credit agreement, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.
	-4	At December 31, 2013, the Operating Partnership had additional borrowing capacity under the unsecured line of credit of up to approximately $772.0 million.
Principal Payments Due for Operating Partnership's Consolidated Indebtedness	'
	As of December 31, 2013, principal payments due for the Operating Partnership’s consolidated indebtedness (excluding debt premiums and discounts) were as follows (in thousands):
	2014	$	341,416
	2015	30,006
	2016	566,516
	2017	439,080
	2018	523,663
	Thereafter (1)	764,153
		$	2,664,834
	-1	Includes $180.0 million in principal payments of the Exchangeable Senior Notes based on a contractual maturity date of January 15, 2030.

Earnings_Per_Share_of_the_Pare1

Earnings Per Share of the Parent Company (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share, Basic and Diluted [Abstract]	'
Schedule of Earnings Per Share, Basic and Diluted	'
	Computations of basic and diluted earnings per share (in thousands, except share data) were as follows:
		Years Ended December 31,
		2013			2012			2011
	Basic earnings per share:
	Income from continuing operations	$	47,209		$	16,133		$	42,240
	Income from continuing operations attributable to noncontrolling interests	(565		)	(20		)	(515		)
	Preferred stock dividends	(2,393		)	(14,603		)	(16,033		)
	Cost on redemption of preferred stock	(6,531		)	—			(165		)
	Net income allocable and distributions in excess of earnings to participating securities (continuing operations)	(1,350		)	(1,300		)	(1,172		)
	Income from continuing operations available to common stockholders - basic	36,370			210			24,355
	(Loss) / income from discontinued operations	—			(4,370		)	474
	Loss / (income) from discontinued operations attributable to noncontrolling interests	—			82			(10		)
	(Loss) / income from discontinued operations available to common stockholders - basic	—			(4,288		)	464
	Net income / (loss) available to common stockholders - basic	$	36,370		$	(4,078	)	$	24,819
	Diluted earnings per share:
	Income from continuing operations available to common stockholders - basic	36,370			210			24,355
	Income from continuing operations attributable to noncontrolling interests in Operating Partnership	819			29			559
	Income from continuing operations available to common stockholders - diluted	37,189			239			24,914
	(Loss) / income from discontinued operations available to common stockholders - basic and diluted	—			(4,288		)	464
	(Loss) / income from discontinued operations attributable to noncontrolling interests in the Operating Partnership	—			(82		)	10
	(Loss) / income from discontinued operations available to common stockholders - basic and diluted	—			(4,370		)	474
	Net income / (loss) available to common stockholders - diluted	$	37,189		$	(4,131	)	$	25,388
	Weighted-average common shares outstanding:
	Basic	182,043,391			152,752,086			132,625,915
	Incremental shares from assumed conversion:
	Performance units	63,017			—			—
	Operating partnership and LTIP units	4,290,614			2,948,301			2,983,928
	Diluted	186,397,022			155,700,387			135,609,843
	Basic and diluted earnings per share:
	Income from continuing operations per share available to common stockholders - basic and diluted	$	0.2		$	—		$	0.19
	Loss from discontinued operations per share available to common stockholders - basic and diluted	$	—		$	(0.03	)	$	—
	Net income / (loss) per share available to common stockholders - basic and diluted	$	0.2		$	(0.03	)	$	0.19

Earnings_Per_Unit_of_the_Opera1

Earnings Per Unit of the Operating Partnership (Tables)	12 Months Ended
	Dec. 31, 2013
Partnership Income [Abstract]	'
Computations of Basic and Diluted Earnings Per Unit	'
	Computations of basic and diluted earnings per unit (in thousands, except unit data) were as follows:
		Years Ended December 31,
		2013			2012			2011
	Basic and diluted earnings per unit:
	Income from continuing operations	$	47,209		$	16,133		$	42,240
	Loss from continuing operations attributable to noncontrolling interests	254			8			44
	Preferred unit distributions	(2,393		)	(14,603		)	(16,033		)
	Cost on redemption of preferred units	(6,531		)	—			(165		)
	Net income allocable and distributions in excess of earnings to participating securities (continuing operations)	(1,354		)	(1,326		)	(1,220		)
	Income from continuing operations available to unitholders - basic and diluted	37,185			212			24,866
	(Loss) / income from discontinued operations - basic and diluted	—			(4,370		)	474
	Net income / (loss) available to unitholders - basic and diluted	$	37,185		$	(4,158	)	$	25,340
	Weighted-average units outstanding:
	Basic	186,333,292			155,670,931			135,549,934
	Incremental units from assumed conversion:
	Performance units	63,017			—			—
	Diluted	186,396,309			155,670,931			135,549,934
	Basic and diluted earnings per unit:
	Income from continuing operations per unit available to unitholders - basic and diluted	$	0.2		$	—		$	0.19
	Loss from discontinued operations per share available to unitholders - basic and diluted	$	—		$	(0.03	)	$	—
	Net income / (loss) per unit available to unitholders, basic and diluted	$	0.2		$	(0.03	)	$	0.19

Investment_in_Unconsolidated_P1

Investment in Unconsolidated Partnerships (Tables)	12 Months Ended
	Dec. 31, 2013
Equity Method Investments and Joint Ventures [Abstract]	'
Summary of Unconsolidated Partnerships	'
	The accompanying consolidated financial statements include investments in two limited liability companies with Prudential Real Estate Investors (“PREI”), 10165 McKellar Court, L.P. (“McKellar Court”), a limited partnership with Quidel Corporation, the tenant which occupies the McKellar Court property and BioPark Fremont, LLC ("BioPark Fremont"), a limited liability company with RPC Poppleton, LLC. General information on the PREI limited liability companies, the McKellar Court partnership and BioPark Fremont (each referred to in this footnote individually as a “partnership” and collectively as the “partnerships”) as of December 31, 2013 was as follows:
	Name	Partner		Company’s		Company’s		Date Acquired
				Ownership		Economic
				Interest		Interest
	PREI I LLC (1)	PREI		20%		20%		April 4, 2007
	PREI II LLC	PREI		20%		20%		April 4, 2007
	McKellar Court (2)	Quidel Corporation		22%		22%		September 30, 2004
	BioPark Fremont (3)	RPC Poppleton, LLC		50%		50%		May 31, 2013
	-1	PREI I LLC owns two properties in Cambridge, Massachusetts. At December 31, 2013, there were $139.0 million in outstanding borrowings on a secured loan facility held by a wholly-owned subsidiary of PREI I LLC, with a contractual interest rate of 3.17% (including the applicable credit spread) and a maturity date of August 13, 2014.
	-2	The Company’s investment in the McKellar Court partnership (maximum exposure to losses) was approximately $12.0 million at December 31, 2013. The Company’s economic interest in the McKellar Court partnership entitles it to 75% of the extraordinary cash flows after repayment of the partners’ capital contributions and 22% of the operating cash flows.
	-3	The Company's partnership interest was acquired in connection with the Company's merger with Wexford.
Summary of Selected Balance Sheet Information	'
	The condensed combined balance sheets for all of the Company’s unconsolidated partnerships were as follows (in thousands):
		December 31,				December 31,
		2013				2012
	Assets:
	Investments in real estate, net	$	262,753			$	257,666
	Cash and cash equivalents (including restricted cash)	3,855				1,968
	Other assets	5,301				4,370
	Total assets	$	271,909			$	264,004
	Liabilities and members’ equity:
	Mortgage notes payable and secured loan	$	151,968			$	149,255
	Other liabilities	12,102				5,988
	Members’ equity	107,839				108,761
	Total liabilities and members equity	$	271,909			$	264,004
	Company’s net investment in unconsolidated partnerships	$	32,137			$	32,367
Schedule of Selected Income Statement Information	'
	The selected data and results of operations for the unconsolidated partnerships were as follows (in thousands):
			Years Ended December 31,
			2013				2012			2011
	Total revenues		$	12,930			$	8,823		$	8,567
	Total expenses		(21,589		)		(19,939		)	(19,868		)
	Loss from continuing operations		(8,659		)		(11,116		)	(11,301		)
	Gain on sale of discontinued operations (1)		—				—			22,927
	Loss from discontinued operations		—				—			(6,677		)
	Net (loss) / income		$	(8,659	)		$	(11,116	)	$	4,949
	Company’s equity in net loss of unconsolidated partnerships		$	(905	)		$	(1,389	)	$	(2,489	)
	Fees earned by the Company (2)		$	260			$	90		$	1,117
	-1	During the year ended December 31, 2011, PREI I LLC recorded a gain on sale of discontinued operations upon sale of certain properties to the Company. In accordance with the equity method of accounting, the Company's share of the equity in net income in PREI I LLC excludes any gain on sale since such gain was generated upon sale of the properties to the Company. The Company recorded a gain on revaluation of the acquired unconsolidated partnership.
	-2	The Company acts as the operating member or partner, as applicable, and day-to-day manager for the partnerships. The Company is entitled to receive fees for providing construction and development services (as applicable) and management services to the PREI joint ventures, which are reflected in tenant recoveries and other income in the consolidated statements of operations.

Derivatives_and_Other_Financia1

Derivatives and Other Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2013
Derivative Instruments and Hedging Activities Disclosure [Abstract]	'
Summary of Derivative Instruments	'
												Fair-Value(1)
		Notional Amount										December 31,			December 31,
						Strike Rate			Effective Date	Expiration Date		2013			2012
	Interest rate swaps	$	200,000			1.163	%		March 30, 2012	March 30, 2017		$	(1,876	)	$	(4,826	)
	Interest rate swaps	200,000				0.701	%		October 1, 2013	October 1, 2016		(288		)	—
	Interest rate swaps(2)	82,595				0.731	%		August 2, 2012	March 30, 2017		1,545			(216		)
	Interest rate swaps(2)	82,595				0.7425	%		August 2, 2012	March 30, 2017		1,519			(243		)
	Total interest rate swaps	$	565,190									$	900		$	(5,285	)
	-1	Fair-value of derivative instruments does not include any related accrued interest payable, which is included in accrued expenses on the accompanying consolidated balance sheets. Derivative valuations are classified in Level 2 of the fair-value hierarchy. Assets are included in other assets and liabilities are included in accounts payable, accrued expenses and other liabilities on the accompanying consolidated balance sheets.
	-2	Translation to U.S. dollars is based on exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively.
Summary of Derivative Instruments, Effect on OCI	'
	The following is a summary of the amount of gain / (loss) recognized in other comprehensive income related to the derivative instruments (in thousands):
			Year Ended
			December 31,
			2013				2012			2011
	Amount of gain / (loss) recognized in other comprehensive income (effective portion):
	Cash flow hedges
	Interest rate swaps		$	3,497			$	(6,863	)	$	(104	)
	Amount of loss reclassified from accumulated other comprehensive loss to income (effective portion):
	Cash flow hedges
	Interest rate swaps (1)		$	(2,619	)		$	(1,578	)	$	(3,385	)
	Forward starting swaps (2)		(6,832		)		(6,933		)	(7,027		)
	Total interest rate swaps		$	(9,451	)		$	(8,511	)	$	(10,412	)
	Amount of gain / (loss) recognized in income (ineffective portion and amount excluded from effectiveness testing):
	Cash flow hedges
	Interest rate swaps		$	—			$	—		(544		)
	Total interest rate swaps		—				—			$	(544	)
	Other derivative instruments		416				(9		)	—
	Total gain / (loss) on derivative instruments		$	416			$	(9	)	$	(544	)
	-1	Amount represents payments made to swap counterparties for the effective portion of interest rate swaps that were recognized as an increase to interest expense for the periods presented (the amount was recorded as an increase and corresponding decrease to accumulated other comprehensive loss in the same accounting period).
	-2	Amount represents reclassifications of deferred interest costs from accumulated other comprehensive loss to interest expense related to the Company’s previously settled forward starting swaps.

FairValue_of_Financial_Instrum1

Fair-Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2013
Fair Value Disclosures [Abstract]	'
Fair-Value and Carrying Value of the Company's Financial Instruments	'
	At December 31, 2013 and December 31, 2012, the aggregate fair-value and the carrying value of the Company’s financial instruments were as follows (in thousands):
		December 31, 2013						December 31, 2012
		Fair-Value (1)			Carrying Value			Fair-Value (1)		Carrying Value
	Mortgage notes payable, net	$	730,394		$	709,324		$	605,948	$	571,652
	Exchangeable Senior Notes	202,626			180,000			209,484		180,000
	Notes due 2016, net	417,040			398,787			421,400		398,289
	Notes due 2020, net	275,600			248,210			292,725		247,984
	Notes due 2022, net	240,400			248,086			261,750		247,904
	Term Loan due 2017 - U.S. dollar	244,751			243,596			243,596		243,596
	Term Loan due 2017 - GBP (2)	165,969			165,190			161,860		161,860
	Term Loan due 2018	350,000			350,000			—		—
	Unsecured line of credit	128,000			128,000			118,000		118,000
	Derivative instruments (3)	(1,316		)	(1,316		)	5,285		5,285
	Available-for-sale securities	19,566			19,566			390		390
	-1	Fair-values of debt and derivative instruments are classified in Level 2 of the fair-value hierarchy. Fair-value of available-for-sale securities are classified in Level 1 of the fair-value hierarchy.
	-2	The principal balance represents the U.S. dollar amount based on the exchange rate of $1.65 to £1.00 and $1.62 to £1.00 at December 31, 2013 and December 31, 2012, respectively.
	-3	The Company’s derivative instruments are reflected in other assets and in accounts payable, accrued expenses and other liabilities on the accompanying consolidated balance sheets based on their respective balances (see Note 9).

Acquisitions_Tables

Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2013
Business Acquisition	'
Schedule of Purchase Price Allocation - excluding Merger	'
	The Company acquired the following properties during the year ended December 31, 2013. The table below reflects the purchase price allocation for these acquisitions, excluding the merger with Wexford, which is discussed below, and the purchase of properties with approximately 274,000 and 300,000 square feet of pre-development and development potential, respectively, for approximately $13.4 million recorded as investments in real estate (in thousands):
	Property		Acquisition Date		Investments in Real Estate				In-Place Lease		Management		Below Market Lease			Acquisition Date Fair- Value
											Agreement
	Woodside Technology Park		February 28, 2013		$	78,681			$	8,162	$	865	$	(708	)	$	87,000
	The Campus at Lincoln Centre		March 20, 2013		37,000				—		—		—			37,000
	320 Charles Street		June 18, 2013		47,018				4,578		—		(2,078		)	49,518
	Total				$	162,699			$	12,740	$	865	$	(2,786	)	$	173,518
	Weighted average intangible amortization life (in months)								61		108		18
Schedule of Purchase Price Allocation - Merger	'
	On May 31, 2013, the Company completed a merger with Wexford. The purchase price allocations of the fair-value of assets acquired, liabilities assumed and consideration paid in the Wexford merger are presented below (in thousands):
		At Acquisition
	Assets:
	Investments in real estate	$	659,517
	Cash and cash equivalents	5,182
	Accounts receivable, net	1,537
	Deferred leasing costs (1)	52,670
	Other assets (2)	89,631
	Total assets	$	808,537
	Liabilities:
	Mortgage notes payable (3)	254,735
	Other liabilities (4)	69,270
	Total liabilities	$	324,005
	Fair value of net assets acquired	$	484,532
	Cash consideration paid for Wexford	$	345,268
	Equity consideration paid for Wexford (5)	123,596
	Contingent consideration in merger with Wexford (6)	15,668
	Total consideration for Wexford	$	484,532
	-1	$52.7 million of acquired in-place leases with a weighted-average lease term of approximately 10.9 years are included in deferred leasing costs.
	-2	$9.6 million of acquired above-market leases with a weighted-average lease term of approximately 11.6 years and $11.0 million of acquired below-market ground leases with a weighted-average lease term of approximately 51.7 years are included in other assets.
	-3	$8.7 million of debt premiums with a weighted-average term of approximately 9.2 years are included in mortgage notes payable, net.
	-4	$31.4 million of acquired below-market leases with a weighted-average lease term of approximately 13.4 years and $2.5 million of acquired above-market ground leases with a weighted-average lease term of approximately 64.0 years are included in other liabilities.
	-5	Consists of 5,568,227 shares of the Parent Company's common stock and 336,960 operating partnership units.
	-6	Includes potential additional consideration to be paid to the seller upon the achievement of certain pipeline development milestones.
Selected Financial Data of the VIEs	'
	Selected financial data of the VIEs at December 31, 2013 and December 31, 2012 consist of the following (in thousands):
		December 31,				December 31,
		2013				2012
	Investment in real estate, net	$	336,832			$	334,331
	Total assets	375,443				369,460
	Total debt	143,067				144,889
	Total liabilities	154,953				149,336
	The Company has determined that certain special purpose entities owning properties under development are VIEs, since there is insufficient capital to finance the remaining development activities without further subordinated financial support. The Company has determined it is the primary beneficiary of these VIEs, because it has the authority to direct the activities which most significantly impact their economic performance. Selected financial data of the VIEs at December 31, 2013 consisted of the following (in thousands):
		December 31,
		2013
	Investment in real estate, net	$	177,901
	Total assets	198,968
	Total liabilities	60,197
Parent Company	'
Business Acquisition	'
Pro Forma Results	'
	The unaudited pro forma revenues and operating income of the Parent Company, including the acquisitions that occurred in 2013 as if they had taken place on January 1, 2012, are as follows (in thousands, except per share amounts):
			Year Ended December 31,
			2013				2012
	Total revenues		$	666,904			$	590,415
	Net income / (loss) available to common stockholders		36,981				(19,493		)
	Net income / (loss) per share available to common stockholders - basic and diluted		$	0.2			$	(0.13	)
BIOMED REALTY, L.P.	'
Business Acquisition	'
Pro Forma Results	'
	The unaudited pro forma revenues and operating income of the Operating Partnership, including the acquisitions that occurred in 2013 as if they had taken place on January 1, 2012, are as follows (in thousands, except per unit amounts):
			Year Ended December 31,
			2013				2012
	Total revenues		$	666,904			$	590,415
	Net income / (loss) available to unitholders		37,800				(19,547		)
	Net income / (loss) per unit available to unitholders - basic and diluted		$	0.2			$	(0.13	)

Discontinued_Operations_Tables

Discontinued Operations (Tables)	12 Months Ended
	Dec. 31, 2013
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	The table below reflects the details of the property and the exchange (in thousands):
	Property		Date of Sale	Original Acquisition Date		Sales Price (1)			Impairment loss
	Forbes Boulevard		April 27, 2012	September 5, 2007		$	28,000		$	(4,552	)
	-1	The sales price was equal to the fair-value of the office property received as consideration in the exchange with the independent third party.
	The results of operations of the Forbes Boulevard property are reported as discontinued operations for all periods presented in the accompanying consolidated financial statements. The following table summarizes the revenue and expense components that comprise income / (loss) from discontinued operations (in thousands):
		Year Ended
		December 31,
		2013			2012			2011
	Total revenues	$	—		$	454		$	1,499
	Total expenses	—			272			1,025
	Income from discontinued operations before impairment loss	—			182			474
	Impairment loss	—			(4,552		)	—
	(Loss) / income from discontinued operations	$	—		$	(4,370	)	$	474

Incentive_Award_Plan_Incentive1

Incentive Award Plan Incentive Award Plan (Tables)	12 Months Ended
	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]	'
Summary of Unvested Restricted Stock and LTIP Units [Abstract]	'
	A summary of the Company’s unvested restricted stock and LTIP units is presented below:
		Unvested Restricted Shares/LTIP Units		Weighted Average Grant-Date Fair-Value
	Balance at December 31, 2010	1,588,060		$	15.15
	Granted	630,337		18.38
	Vested	(467,120	)	16.03
	Forfeited	(30,215	)	16.17
	Balance at December 31, 2011	1,721,062		16.09
	Granted	395,350		18.46
	Vested	(520,258	)	15.17
	Forfeited	(35,642	)	15.97
	Balance at December 31, 2012	1,560,512		17
	Granted	657,106		20.33
	Vested	(665,808	)	15.91
	Forfeited	(39,805	)	18.15
	Balance at December 31, 2013	1,512,005		$	18.91
Incentive Award Plan Selected Data [Line Items]	'
	Incentive Award Plan
	The Company has adopted the 2013 Amendment and Restatement of the BioMed Realty Trust, Inc. and BioMed Realty, L.P. 2004 Incentive Award Plan (the “Plan”). The Plan provides for grants to directors, employees and consultants of the Company and the Operating Partnership (and their respective subsidiaries) of stock options, restricted stock, LTIP units, stock appreciation rights, dividend equivalents, and other incentive awards. The Company has reserved 10,740,000 shares of common stock for issuance pursuant to the Plan, subject to adjustments as set forth in the Plan. As of December 31, 2013, 6,896,224 shares of common stock or awards convertible into or exchangeable for common stock remained available for future issuance under the Plan. Each LTIP unit and each Performance Unit issued will count as one share of common stock for purposes of calculating the limit on shares that may be issued. Compensation cost for these incentive awards is measured based on the fair-value of the award on the grant date (fair-value is calculated based on the closing price of the Company’s common stock on the date of grant) and is recognized as expense over the respective vesting period, which for restricted stock awards and LTIP units is generally four to five years. Fully vested incentive awards may be settled for either cash or stock depending on the Company’s election and the type of award granted. Participants are entitled to cash dividends and may vote such awarded shares, but the sale or transfer of such shares is limited during the restricted or vesting period. The restricted stock grants may only be settled for stock whereas the LTIP units may be redeemed for either cash or common stock, at the Company’s election.
	The Parent Company has awarded Performance Units to certain of its executive officers, which represent the maximum number of Performance Units that may vest. Each Performance Unit represents a contingent right to receive one share of the Parent Company’s common stock if vesting conditions are satisfied. Performance Units vest at the end of designated time periods (each, a “Performance Period”) based upon the Parent Company’s total stockholder return relative to its peer group (the “Market Conditions”). The grant date fair-value of the Performance Units was estimated using a Monte Carlo simulation which considered the likelihood of achieving the Market Conditions. The Monte Carlo simulation uses a statistical formula underlying the Black-Scholes and binomial formulas, and such simulation was run approximately 100,000 times. For each simulation, the value of the payoff was calculated at the end of the respective Performance Period and was then discounted to the grant date at a risk-free interest rate. The expected value of the Performance Units on the grant date was determined by simulating the total shareholder return for the Company and the peer group considering the stock price variance for each of the peer group companies, compared to each other and the Company's stock estimating the rank of the Company's stock. The valuation was performed in a risk-neutral framework, so no assumption was made with respect to an equity risk premium. Other significant assumptions used in the valuation included an expected term of 24 and 36 months, an average risk-free interest rate of 0.35%, and an average dividend yield of 4.41%. No dividends will be paid or accrued on the Performance Units, and shares of the Parent Company’s common stock will not be issued until vesting of the Performance Units occurs.
	A summary of the Company’s unvested restricted stock and LTIP units is presented below:
		Unvested Restricted Shares/LTIP Units		Weighted Average Grant-Date Fair-Value
	Balance at December 31, 2010	1,588,060		$	15.15
	Granted	630,337		18.38
	Vested	(467,120	)	16.03
	Forfeited	(30,215	)	16.17
	Balance at December 31, 2011	1,721,062		16.09
	Granted	395,350		18.46
	Vested	(520,258	)	15.17
	Forfeited	(35,642	)	15.97
	Balance at December 31, 2012	1,560,512		17
	Granted	657,106		20.33
	Vested	(665,808	)	15.91
	Forfeited	(39,805	)	18.15
	Balance at December 31, 2013	1,512,005		$	18.91
	Selected data of the Company’s incentive award plan is presented below (in thousands, except share and period amounts):
		Years Ended December 31,
		2013			2012		2011
	Aggregate value of restricted stock/LTIP Units granted	$	13,234		$	7,300	$	11,612
	Aggregate value of Performance Units granted	$	4,973		$	3,329	$	—
	Fair-value of stock/LTIP Units vested	$	13,321		$	9,502	$	8,547
	Stock-based compensation expense recognized in general and administrative expenses and rental operations expense - restricted stock/LTIP Units	$	10,134		$	9,556	$	7,582
	Stock-based compensation expense recognized in general and administrative expenses - Performance Units	$	2,445		$	1,974	$	—
	Shares surrendered to the Company and retired in lieu of cash payments for taxes due on the vesting of restricted stock	253,671			178,915		129,342
	Data at period end:
	Total compensation to be expensed related to unvested awards in future periods - restricted stock	$	17,145
	Weighted-average expense period (in years) - restricted stock	2.6
	Total compensation to be expensed related to unvested awards in future periods - Performance Units	$	2,528
	Weighted-average expense period (in years) - Performance Units	1.5

Quarterly_Financial_Informatio2

Quarterly Financial Information of the Parent Company Quarterly Financial Information of the Parent Company (Tables) (Parent Company)	12 Months Ended
	Dec. 31, 2013
Parent Company	'
Quarterly Financial Information Disclosure [Line Items]	'
Schedule of Quarterly Financial Information [Table Text Block]	'
	The Company’s selected quarterly information for the years ended December 31, 2013 and 2012 (in thousands, except per share data) was as follows.
		2013 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	157,993		$	159,232		$	159,639		$	160,450
	Net income	10,576			4,136			15,037			17,458
	Net (income) / loss attributable to noncontrolling interests	(297		)	111			(234		)	(146		)
	Preferred stock dividends	—			—			—			(2,393		)
	Net income available to common stockholders	$	10,279		$	4,247		$	14,803		$	8,388
	Net income per share available to common stockholders - basic and diluted	$	0.05		$	0.02		$	0.08		$	0.05
		2012 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	138,771		$	134,537		$	124,848		$	120,012
	Income / (loss) from continuing operations	8,260			6,455			(5,283		)	6,702
	Income / (loss) from discontinued operations	—			—			49			(4,420		)
	Net income / (loss)	8,260			6,455			(5,234		)	2,282
	Net (income) / loss attributable to noncontrolling interests	(93		)	(46		)	172			30
	Preferred stock dividends	(3,651		)	(3,651		)	(3,651		)	(3,651		)
	Net income / (loss) available to common stockholders	$	4,516		$	2,758		$	(8,713	)	$	(1,339	)
	Income / (loss) from continuing operations per share available to common stockholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	0.02
	Net income / (loss) per share available to common stockholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	(0.01	)
	-1	The sum of quarterly financial data may vary from the annual data due to rounding.

Quarterly_Financial_Informatio3

Quarterly Financial Information of the Operating Partnership Quarterly Financial Information of the Operating Partnership (Tables) (BIOMED REALTY, L.P.)	12 Months Ended
	Dec. 31, 2013
BIOMED REALTY, L.P.	'
Quarterly Financial Information Disclosure [Line Items]	'
Schedule of Quarterly Financial Information [Table Text Block]	'
	The Company’s selected quarterly information for the years ended December 31, 2013 and 2012 (in thousands, except per share data) was as follows.
		2013 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	157,993		$	159,232		$	159,639		$	160,450
	Net income	10,576			4,136			15,037			17,458
	Net (income) / loss attributable to noncontrolling interests	(12		)	229			29			8
	Preferred unit distributions	—			—			—			(2,393		)
	Net income available to unitholders	$	10,564		$	4,365		$	15,066		$	8,542
	Net income per unit available to unitholders - basic and diluted	$	0.05		$	0.02		$	0.08		$	0.05
		2012 Quarter Ended(1)
		31-Dec			30-Sep			30-Jun			31-Mar
	Total revenues	$	138,771		$	134,537		$	124,848		$	120,012
	Income / (loss) from continuing operations	8,260			6,455			(5,283		)	6,702
	Income / (loss) from discontinued operations	—			—			49			(4,420		)
	Net income / (loss)	8,260			6,455			(5,234		)	2,282
	Net (income) / loss attributable to noncontrolling interests	(7		)	7			6			4
	Preferred unit distributions	(3,651		)	(3,651		)	(3,651		)	(3,651		)
	Net income / (loss) available to unitholders	$	4,602		$	2,811		$	(8,879	)	$	(1,365	)
	Income / (loss) from continuing operations per unit available to unitholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	0.02
	Net income / (loss) per unit available to unitholders - basic and diluted	$	0.03		$	0.02		$	(0.06	)	$	(0.01	)
	-1	The sum of quarterly financial data may vary from the annual data due to rounding.

Organization_of_the_Parent_Com1

Organization of the Parent Company and Description of Business (Details)	Dec. 31, 2013	Dec. 31, 2012
Organization, Consolidation and Presentation of Financial Statements	'	'
Equity Method Investment, Ownership Percentage	100.00%	100.00%
Remaining Ownership Interest Held by Limited Partners	2.70%	'
Parent Company	'	'
Organization, Consolidation and Presentation of Financial Statements	'	'
Equity Method Investment, Ownership Percentage	97.30%	98.10%

Basis_of_Presentation_and_Summ3

Basis of Presentation and Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011
	VIEs
	Extensions
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
Provision for Doubtful Accounts	$931,000	$1,700,000		$2,300,000
Real Estate Inventory, Capitalized Interest Costs	-14,200,000	-8,600,000		-7,600,000
Revenue from properties outside the United States, net	45,300,000	'		'
Real Estate Investment Property, Net	5,217,902,000	4,319,716,000		'
Number of Variable Interest Entities that the Company is the Primary Beneficiary	5	'		'
Fair Value	'	28,000,000	[1]	'
Impairment of Long-Lived Assets to be Disposed of	0	4,552,000		'
Reclassification Of Other Than Temporary Unrealized Loss From Accumulated Other Comprehensive Income To General And Administrative Expense	-2,800,000	'		'
Cost-method Investments, Other than Temporary Impairment	2,000,000	'		'
Other Asset Impairment Charges	-825,000	'		'
Receivable with Imputed Interest, Due Date	30-Sep-14	'		'
Number of extension options	2	'		'
Extension options	'1 year	'		'
Debt Instrument, Basis Spread on Variable Rate	550.00%	'		'
Debt Instrument, Interest Rate, Stated Percentage	6.50%	'		'
Investment In Construction Loan	151,800,000	21,700,000		'
Lease Termination Revenue	42,800,000	3,500,000		6,200,000
Capitalized Payroll	-3,600,000	-2,000,000		-1,300,000
Finite-Lived Intangible Assets, Net	198,067,000	172,363,000		'
Allowance for Doubtful Accounts Receivable	-2,300,000	-4,200,000		-2,900,000
Foreign	'	'		'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
Revenue from properties outside the United States, net	18,200,000	10,300,000		'
Percentage of Company's total revenue	2.90%	2.00%		'
Real Estate Investment Property, Net	190,200,000	188,800,000		'
Boston Development Project	'	'		'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
BioMed Realty Trust Interest in Construction Loan	255,000,000	'		'
Construction Loan	355,000,000	'		'
Square Footage of Real Estate Property	1,100,000	'		'
Percent Leased	95.00%	'		'
Science Center at Oyster Point	'	'		'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
Real Estate Investment Property, Net	104,648,000	'		'
Lease Termination Revenue	46,500,000	'		'
320 Bent Street	'	'		'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
Real Estate Investment Property, Net	85,914,000	'		'
Lease Termination Revenue	8,700,000	'		'
Deferred Leasing Costs [Member]	'	'		'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'		'
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	40,251,000	'		'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	31,707,000	'		'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	25,031,000	'		'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	22,959,000	'		'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	18,581,000	'		'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	59,538,000	'		'
Finite-Lived Intangible Assets, Net	$198,067,000	'		'
[1]	The sales price was equal to the fair-value of the office property received as consideration in the exchange with the independent third party.

Basis_of_Presentation_and_Summ4

Basis of Presentation and Summary of Significant Accounting Policies (Selected Financial Data of the VIEs) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'	'
Investment in Real Estate, Net	$336,832	$334,331
Total Assets	375,443	369,460
Total Debt	143,067	144,889
Total Liabilities	$154,953	$149,336

Basis_of_Presentation_and_Summ5

Basis of Presentation and Summary of Significant Accounting Policies (Investments in Real Estate, Net) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'	'
Land	$713,955	$702,993
Land Under Development	119,325	48,744
Buildings and Improvements	4,854,175	4,028,089
Construction in Progress	316,025	143,340
Real Estate Investment Property, at Cost	6,003,480	4,923,166
Accumulated Depreciation	-785,578	-603,450
Real Estate Investment Property, Net	$5,217,902	$4,319,716

Basis_of_Presentation_and_Summ6

Basis of Presentation and Summary of Significant Accounting Policies (Deferred Leasing Costs, Net) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Deferred Leasing Costs	'	'
Finite-Lived Intangible Assets, Gross	$482,696	$396,659
Finite-Lived Intangible Assets, Accumulated Amortization	-284,629	-224,296
Finite-Lived Intangible Assets, Net	198,067	172,363
Leases, Acquired-in-Place	'	'
Deferred Leasing Costs	'	'
Finite-Lived Intangible Assets, Gross	365,753	303,521
Finite-Lived Intangible Assets, Accumulated Amortization	-233,935	-185,463
Finite-Lived Intangible Assets, Net	131,818	118,058
Acquired Management Agreements	'	'
Deferred Leasing Costs	'	'
Finite-Lived Intangible Assets, Gross	25,801	24,963
Finite-Lived Intangible Assets, Accumulated Amortization	-20,053	-15,242
Finite-Lived Intangible Assets, Net	5,748	9,721
Deferred Leasing and Other Direct Costs	'	'
Deferred Leasing Costs	'	'
Finite-Lived Intangible Assets, Gross	91,142	68,175
Finite-Lived Intangible Assets, Accumulated Amortization	-30,641	-23,591
Finite-Lived Intangible Assets, Net	$60,501	$44,584

Basis_of_Presentation_and_Summ7

Basis of Presentation and Summary of Significant Accounting Policies (Deferred Leasing Costs-Estimated Amortization) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Net	$198,067	$172,363
Deferred Leasing Costs [Member]	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	40,251	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	31,707	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	25,031	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	22,959	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	18,581	'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	59,538	'
Finite-Lived Intangible Assets, Net	$198,067	'

Basis_of_Presentation_and_Summ8

Basis of Presentation and Summary of Significant Accounting Policies (Impact of Straight Line Rent Revenue, Acquired above-market lease revenue, Acquired below-market lease revenue and Lease incentive revenue) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounting Policies [Abstract]	'	'	'
Straight-line rent revenue	$23,136	$23,288	$25,243
Acquired Above Market Lease Revenue	-11,913	-9,977	-9,607
Acquired Below Market Lease Revenue	4,325	1,684	1,453
Lease Incentive Revenue	-2,295	-2,969	-2,246
Lease Revenue Net	$13,253	$12,026	$14,843

Basis_of_Presentation_and_Summ9

Basis of Presentation and Summary of Significant Accounting Policies (Estimated Minimum Rents) (Details) (USD $)	Dec. 31, 2013
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$455,359
Operating Leases, Future Minimum Payments, Due in Two Years	450,564
Operating Leases, Future Minimum Payments, Due in Three Years	424,331
Operating Leases, Future Minimum Payments, Due in Four Years	400,787
Operating Leases, Future Minimum Payments, Due in Five Years	342,864
Operating Leases, Future Minimum Payments, Due Thereafter	2,037,341
Operating Leases, Future Minimum Payments Due	$4,111,246

Recovered_Sheet1

Basis of Presentation and Summary of Significant Accounting Policies (Revenue Recognition-Estimated Amortization) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Net	$198,067	$172,363
Acquired Above Market Leases [Member]	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	-4,457	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	-1,942	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	-1,317	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	-1,196	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	-1,112	'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	-5,804	'
Finite-Lived Intangible Assets, Net	-15,828	'
Acquired Below Market Leases [Member]	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	5,262	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	3,721	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	3,487	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	3,435	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	3,427	'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	18,789	'
Finite-Lived Intangible Assets, Net	38,121	'
Lease Incentives [Member]	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	-2,232	'
Finite-Lived Intangible Assets, Amortization Expense, Year Two	-2,225	'
Finite-Lived Intangible Assets, Amortization Expense, Year Three	-2,152	'
Finite-Lived Intangible Assets, Amortization Expense, Year Four	-1,728	'
Finite-Lived Intangible Assets, Amortization Expense, Year Five	-1,329	'
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	-9,973	'
Finite-Lived Intangible Assets, Net	($19,639)	'

Recovered_Sheet2

Basis of Presentation and Summary of Significant Accounting Policies (Investments) (Details) (USD $)	Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Accounting Policies [Abstract]	'		'
Available-for-sale securities, historical cost	$8,543		$275
Unrealized gain, net	11,023		115
Available-for-sale securities, fair-value	19,566	[1]	390	[1]
Privately-held securities, cost basis	18,485		12,280
Total equity securities	$38,051		$12,670
[1]	Determination of fair-value is classified as Level 1 in the fair-value hierarchy based on the use of quoted prices in active markets.

Recovered_Sheet3

Basis of Presentation and Summary of Significant Accounting Policies (Income Tax Treatment for Dividends) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'	'
Common Stock, Dividends, Per Share, Cash Paid	$0.94	$0.85	$0.77
Percentage Of Common Stock Dividend	100.00%	100.00%	100.00%
Preferred Stock, Dividends, Per Share, Cash Paid	$0.76	$1.84	$1.84
Percentage Of Preferred Stock Dividend	100.00%	100.00%	100.00%
Ordinary Income [Member]	'	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'	'
Common Stock, Dividends, Per Share, Cash Paid	$0.94	$0.63	$0.44
Percentage Of Common Stock Dividend	100.00%	74.12%	57.14%
Preferred Stock, Dividends, Per Share, Cash Paid	$0.76	$1.84	$1.84
Percentage Of Preferred Stock Dividend	100.00%	100.00%	100.00%
Capital Gains [Member]	'	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'	'
Common Stock, Dividends, Per Share, Cash Paid	$0	$0	$0
Preferred Stock, Dividends, Per Share, Cash Paid	$0	$0	$0
Percentage Of Preferred Stock Dividend	0.00%	0.00%	0.00%
Return On Capital [Member]	'	'	'
Basis of Presentation and Summary of Significant Accounting Policies [Line Items]	'	'	'
Common Stock, Dividends, Per Share, Cash Paid	'	$0.22	$0.33
Percentage Of Common Stock Dividend	'	25.88%	42.86%
Preferred Stock, Dividends, Per Share, Cash Paid	$0	$0	$0
Percentage Of Preferred Stock Dividend	0.00%	0.00%	0.00%

Equity_of_the_Parent_Company_N

Equity of the Parent Company (Narrative) (Details) (USD $)

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2012

Dec. 31, 2010

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2013

Dec. 31, 2013

Jun. 30, 2013

Dec. 31, 2013

Jun. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Common Stock

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Wexford

Wexford

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

Preferred Stock Repurchased

Preferred Stock Repurchased

Performance Shares

Performance Shares

Limited Partner

Limited Partner

Limited Partner

Limited Partner

Limited Partner

Limited Partner

Limited Partner

Common Stock

Common Stock

Common Stock

Common Stock

Common Stock

Common Stock

Series A Preferred Stock

Series A Preferred Stock

Operating Partnership Units and LTIP Units

Restricted Stock Issued to Employees

Restricted Stock Issued to Board Members

Common Stock

Series A Preferred Stock

Series A Preferred Stock

Series A Preferred Stock

Series A Preferred Stock

Parent Company

Parent Company

Parent Company

Parent Company

Common Stock

Common Stock

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

BIOMED REALTY, L.P.

Common Stock

Common Stock

Common Stock

Common Stock

Common Stock

Equity of the Parent Company

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Restricted Stock Awards Issued

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

625,840

31,266

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares surrendered to the Company and retired in lieu of cash payments for taxes due on the vesting of restricted stock

'

'

'

'

'

'

'

253,671

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Shares forfeited during the period

'

'

'

'

'

'

'

39,805

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures

'

'

'

'

'

'

'

'

'

'

'

'

343,561

179,115

470,780

'

'

'

'

'

'

'

20,069

'

'

'

'

'

'

'

'

'

'

'

'

'

'

132,441

'

'

'

Stock Issued During Period, Shares, New Issues

'

'

'

'

'

'

'

'

'

'

17,250,000

14,605,000

31,855,000

'

22,562,922

'

'

'

'

'

'

'

41,568

'

'

'

'

'

'

'

'

'

'

'

'

'

2,034,211

2,034,211

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value

'

'

'

'

'

'

'

$3,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

$3,600,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value

'

'

'

'

'

'

'

2,100,000

'

'

'

'

'

'

'

'

'

'

'

'

'

3,200,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term

'

'

'

'

'

'

'

'1 year 9 months 10 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'3 years 8 months 12 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Performance units forfeited during the period

39,805

35,642

30,215

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

116,072

'

'

'

'

'

'

'

Performance units

657,106

395,350

630,337

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

136,296

406,288

'

'

'

'

'

'

'

Stock Issued During Period, Value, New Issues

'

'

'

'

'

'

287,000,000

641,097,000

'

399,571,000

'

'

319,000

'

225,000

'

'

'

'

'

'

'

'

682,615,000

'

399,571,000

'

'

'

'

'

'

'

'

'

'

'

41,518,000

'

'

'

Stock Redeemed or Called During Period, Shares

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7,920,000

'

'

'

'

'

'

'

'

'

'

Proceeds from Issuance of Common Stock

'

'

'

'

'

354,100,000

'

668,553,000

'

404,328,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Merger Issues

'

'

'

5,568,227

'

'

'

'

'

'

5,568,227

'

5,568,227

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stock Issued During Period, Units, Issued in Connection with Wexford Merger

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

336,960

336,960

'

336,960

'

'

'

Common Stock, Shares Outstanding

'

'

'

'

'

'

'

'

'

'

'

'

192,115,002

154,327,818

154,101,482

131,046,509

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Partnership Units, Shares Outstanding

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5,083,400

'

'

'

'

'

'

'

'

7,920,000

7,920,000

9,200,000

'

'

'

'

'

'

'

5,415,974

2,932,758

2,979,979

3,001,250

LTIP Units, Shares Outstanding

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

332,574

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Redemption Of Series Preferred Stock

'

'

'

'

'

'

'

-198,000,000

'

-31,109,000

'

'

'

'

'

'

-191,469,000

-30,944,000

'

'

'

'

'

-198,000,000

'

-31,109,000

-198,000,000

-31,109,000

'

'

198,000,000

'

'

'

'

'

'

'

'

'

'

Payments for Repurchase of Redeemable Preferred Stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

25

'

'

'

'

'

'

'

'

'

'

Payments of Ordinary Dividends, Preferred Stock and Preference Stock

'

'

'

'

'

'

'

6,045,000

14,601,000

16,623,000

'

'

'

'

'

'

'

'

'

'

'

'

'

6,045,000

14,601,000

16,623,000

'

'

'

'

2,400,000

'

'

'

'

'

'

'

'

'

'

Preferred Stock, Dividend Rate, Per-Dollar-Amount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$0.30

'

'

'

'

'

'

'

'

'

'

Cost on redemption of preferred stock / units

'

'

'

'

'

'

'

-6,531,000

'

-165,000

'

'

'

'

'

'

'

'

'

'

'

'

'

-6,531,000

'

-165,000

'

'

'

'

'

6,500,000

'

'

'

'

'

'

'

'

'

Noncontrolling Interest Redemption Value

'

'

'

'

'

'

'

$99,400,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Average Closing Price Per Common Share

'

'

'

'

$18.35

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Noncontrolling Interest Redemption Value Calculation Days

'

'

'

'

'10 days

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Equity_of_the_Parent_Company_D

Equity of the Parent Company (Dividends and Distributions) (Details) (USD $)

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

Dec. 31, 2013

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2011

Mar. 31, 2013

Common stock and OP units

Common stock and OP units

Common stock and OP units

Common stock and OP units

Common stock and OP units

Series A Preferred Stock

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Parent Company

Series A Preferred Stock

Series A Preferred Stock

Preferred Stock Repurchased

Equity of the Parent Company

'

'

'

'

'

'

'

'

'

'

'

'

'

Declaration Date

'

12-Dec-13

16-Sep-13

14-Jun-13

15-Mar-13

'

'

'

'

'

'

'

'

Amount Per Common Share/Unit

'

$0.25

$0.24

$0.24

$0.24

'

'

'

'

'

'

'

'

Dividend and Distribution Payable Date

'

15-Jan-14

15-Oct-13

15-Jul-13

15-Apr-13

'

'

'

'

'

'

'

'

Dividend and Distribution Amount

$184,988,000

$49,383,000

$46,418,000

$46,381,000

$40,413,000

$182,595,000

$2,393,000

[1]

'

'

'

'

'

'

Stock Redeemed or Called During Period, Shares

'

'

'

'

'

'

'

'

'

'

'

'

7,920,000

Redemption Of Series Preferred Stock

'

'

'

'

'

'

'

-198,000,000

'

-31,109,000

-191,469,000

-30,944,000

198,000,000

Payments for Repurchase of Redeemable Preferred Stock

'

'

'

'

'

'

'

'

'

'

'

'

25

Payments of Ordinary Dividends, Preferred Stock and Preference Stock

'

'

'

'

'

'

'

$6,045,000

$14,601,000

$16,623,000

'

'

$2,400,000

Preferred Stock, Dividend Rate, Per-Dollar-Amount

'

'

'

'

'

'

'

'

'

'

'

'

$0.30

[1]

On MarchB 15, 2013, the Parent Company redeemed all 7,920,000 outstanding shares of its Series A preferred stock for approximately $198.0 million, or $25.00 per share, net of accrued dividends of approximately $2.4 million, or $0.30217 per share.

Equity_of_the_Parent_Company_E

Equity of the Parent Company Equity of the Parent Company (Changes in Accumulated Other Comprehensive Loss by Component) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Other Comprehensive Income (Loss), Net of Tax	$24,250		'	'	'
Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Accumulated other comprehensive loss, net	-32,923		-54,725	'	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	12,963		'	'	'
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	2,987,025		2,484,541	2,612,196	2,312,896
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	10,907		-390	-5,131	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	11,287	[1]	'	'	'
Available-for-sale Securities, Change in Net Unrealized Holding Gain (Loss), Net of Tax	10,907		-390	-5,131	'
Other Comprehensive Income (Loss), Net of Tax	24,250		5,517	10,955	'
Interest Rate Swaps | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	'		-6,863	-104	'
Accumulated Translation Adjustment [Member] | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Accumulated other comprehensive loss, net	3,905		3,543	'	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	395		'	'	'
Other Comprehensive Income (Loss), Net of Tax	395		'	'	'
Accumulated Other Comprehensive Income (Loss) | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	-32,923		-54,725	-60,138	-70,857
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax	8,824		-382	-5,021	'
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	6,665		6,803	6,877	'
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Accumulated other comprehensive loss, net	8,938		114	'	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	9,071		'	'	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1,836		'	'	'
Other Comprehensive Income (Loss), Net of Tax	10,907		'	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Accumulated other comprehensive loss, net	-45,766		-58,382	'	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	9,451		'	'	'
Other Comprehensive Income (Loss), Net of Tax	12,948		'	'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | Interest Rate Swaps | Parent Company	'		'	'	'
Accumulated Other Comprehensive Income Loss [Line Items]	'		'	'	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	$3,497		'	'	'
[1]	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.

Equity_of_the_Parent_Company_V

Equity of the Parent Company (Vested Ownership Interests) (Details)	Dec. 31, 2013	Dec. 31, 2012
Equity of the Parent Company	'	'
Operating Partnership Units and LTIP Units	195,959,961	155,757,733
Equity Method Investment, Ownership Percentage	100.00%	100.00%
Parent Company	'	'
Equity of the Parent Company	'	'
Operating Partnership Units and LTIP Units	190,676,428	152,853,368
Equity Method Investment, Ownership Percentage	97.30%	98.10%
Operating Partnership and LTIP Units Held By Employees and Related Parties	'	'
Equity of the Parent Company	'	'
Operating Partnership Units and LTIP Units	2,656,388	2,339,314
Equity Method Investment, Ownership Percentage	1.40%	1.50%
Operating Partnership and LTIP Units Held By Third Parties	'	'
Equity of the Parent Company	'	'
Operating Partnership Units and LTIP Units	2,627,145	565,051
Equity Method Investment, Ownership Percentage	1.30%	0.40%

Capital_of_the_Operating_Partn2

Capital of the Operating Partnership (Narrative) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012
In Millions, except Share data, unless otherwise specified			BIOMED REALTY, L.P.	Parent Company	Parent Company	Parent Company	Parent Company
Capital of the Operating Partnership [Line Items]	'	'	'	'	'	'	'
Partners' Capital Account, Units	'	'	197,198,402	'	'	'	'
LTIP Units, Shares Outstanding	'	'	332,574	'	'	'	'
Equity Method Investment, Ownership Percentage	100.00%	100.00%	'	'	'	97.30%	98.10%
Noncontrolling Interest Redemption Value	'	'	'	'	$99.40	'	'
Average Closing Price Per Common Share	'	'	'	$18.35	'	'	'
Noncontrolling Interest Redemption Value Calculation Days	'	'	'	'10 days	'	'	'

Capital_of_the_Operating_Partn3

Capital of the Operating Partnership Capital of the Operating Partnership (Changes in Accumulated Other Comprehensive Loss by Component) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Capital of the Operating Partnership [Line Items]	'		'	'
Other Comprehensive Income (Loss), Net of Tax	$24,250		'	'
BIOMED REALTY, L.P.	'		'	'
Capital of the Operating Partnership [Line Items]	'		'	'
Accumulated other comprehensive loss, net	-30,663		-53,077	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	12,963		'	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	11,287	[1]	'	'
Other Comprehensive Income (Loss), Net of Tax	24,250		5,517	10,955
Accumulated Translation Adjustment [Member] | BIOMED REALTY, L.P.	'		'	'
Capital of the Operating Partnership [Line Items]	'		'	'
Accumulated other comprehensive loss, net	4,006		3,611	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	395		'	'
Other Comprehensive Income (Loss), Net of Tax	395		'	'
Accumulated Net Unrealized Investment Gain (Loss) [Member] | BIOMED REALTY, L.P.	'		'	'
Capital of the Operating Partnership [Line Items]	'		'	'
Accumulated other comprehensive loss, net	9,186		115	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	9,071		'	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	1,836		'	'
Other Comprehensive Income (Loss), Net of Tax	10,907		'	'
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] | BIOMED REALTY, L.P.	'		'	'
Capital of the Operating Partnership [Line Items]	'		'	'
Accumulated other comprehensive loss, net	-43,855		-56,803	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	3,497		'	'
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	9,451		'	'
Other Comprehensive Income (Loss), Net of Tax	$12,948		'	'
[1]	Amounts reclassified from loss on derivative instruments are included in interest expense, net in the consolidated statements of operations. See Note 9 for further information.

Debt_Debt_Narrative_Details

Debt Debt (Narrative) (Details)

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2013

Sep. 26, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2011

Dec. 31, 2013

Sep. 30, 2013

Sep. 30, 2013

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

USD ($)

USD ($)

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Exchangeable Senior Notes

Exchangeable Senior Notes

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Mortgage Notes Payable

Mortgage Notes Payable

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan Due 2018 [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Senior Notes Due Twenty Twenty [Member]

Unsecured Senior Notes Due Twenty Twenty [Member]

Unsecured Senior Notes Due Twenty Twenty-Two [Member]

Unsecured Senior Notes Due Twenty Sixteen [Member]

Prime Rate [Member]

Prime Rate [Member]

Federal Funds Rate [Member]

Federal Funds Rate [Member]

Reserve-Adjusted LIBOR [Member]

Reserve-Adjusted LIBOR [Member]

Reserve-Adjusted LIBOR [Member]

Reserve-Adjusted LIBOR [Member]

USD ($)

Interest Rate Swaps - $200M (2)

Interest Rate Swaps - $200M (2)

USD ($)

USD ($)

USD ($)

London Interbank Offered Rate (LIBOR)

London Interbank Offered Rate (LIBOR)

Prime Rate [Member]

Federal Funds Rate

Federal Funds Rate

Projects Excluding CFLS

CFLS

USD ($)

USD ($)

USD ($)

London Interbank Offered Rate (LIBOR)

London Interbank Offered Rate (LIBOR)

USD ($)

USD ($)

Minimum [Member]

Maximum [Member]

London Interbank Offered Rate (LIBOR)

London Interbank Offered Rate (LIBOR)

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Debt [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

number_of_years

USD ($)

One-Month LIBOR

One-Month LIBOR

Maximum [Member]

Minimum [Member]

Maximum [Member]

Reserve-Adjusted LIBOR [Member]

Reserve-Adjusted LIBOR [Member]

Rate

Rate

Reserve-Adjusted LIBOR [Member]

Reserve-Adjusted LIBOR [Member]

USD ($)

GBP (£)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

number_of_years

number_of_years

number_of_years

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Minimum [Member]

Maximum [Member]

Debt Instruments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument Payable Dates

'

'

'

'

'

'

'January 15 and July 15

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'April 15 and October 15

'January 15 and July 15

'April 15 and October 15

'

'

'

'

'

'

'

'

Debt Instrument, Date of First Required Payment

'

'

'

'

'

'

15-Jul-10

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

15-Oct-10

15-Jan-13

15-Oct-11

'

'

'

'

'

'

'

'

Foreign Currency Exchange Rate, Translation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.65

1.62

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Investment In Real Estate Property Mortgaged

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$1,200,000,000

$1,000,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Increment of Dividends per Common Share Increase Exchange Rate

'

'

'

'

'

$0.14

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Convertible, Conversion Ratio

'

'

'

'

'

57.8068

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Conversion, Original Debt, Amount

'

'

'

'

'

1,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Exchange Price

'

'

'

'

'

'

$18.16

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Exchangeable Note Exchange Date

'

'

'

'

'

'

'2015-01-15

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Convertible, Conversion Price

'

$17.30

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Dividends Payable Date of Ex-Dividend

'

'

'

'

'

26-Sep-13

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

exchangeable note redemption date

'

'

'

'

'

'

'2015-01-21

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Long Term Debt Redemption Percentage Of Principal

'

'

'

'

'

'

100.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100.00%

100.00%

100.00%

'

'

'

'

'

'

'

'

Debt Instrument, Issuance Date

'

'

'

'

'

'

11-Jan-10

24-Sep-13

'

'

'

'

'

'

'

'

'

'

14-Jul-11

'

'

'

30-Mar-12

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

29-Apr-10

28-Jun-12

30-Mar-11

'

'

'

'

'

'

'

'

Line of Credit Facility, Current Borrowing Capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

750,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Initial Exchange Rate

'

'

'

'

'

'

55.0782

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Face Amount

'

'

'

'

'

'

'

'

1,250,000,000

'

'

'

'

'

'

'

'

'

'

900,000,000

'

'

'

400,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

250,000,000

250,000,000

400,000,000

'

'

'

'

'

'

'

'

Percentage Of Long Term Debt Principal Paid By Underwriters

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

98.98%

99.13%

99.37%

'

'

'

'

'

'

'

'

Debt Instrument, Interest Rate, Stated Percentage

6.50%

'

'

'

'

'

3.75%

'

'

'

'

'

'

'

'

'

'

'

'

1.46%

[1],[2]

'

'

'

'

'

'

'

'

'

'

'

2.14%

[3]

2.14%

[3]

'

1.67%

[1]

1.82%

[3]

'

6.13%

6.13%

4.25%

3.85%

'

'

'

'

'

'

'

'

Debt Instrument, Maturity Date

'

'

'

'

'

'

15-Jan-30

24-Mar-18

'

'

'

'

'

'

'

'

'

'

'

24-Mar-18

[1],[2]

'

'

'

30-Mar-17

'

'

'

'

'

'

'

30-Mar-17

[3]

30-Mar-17

[3]

'

24-Mar-18

[1]

30-Mar-17

[3]

'

'

15-Apr-20

15-Jul-22

15-Apr-16

'

'

'

'

'

'

'

'

Debt Instrument, Maximum Borrowing Capacity

'

'

'

'

'

'

'

'

1,800,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Maturity Date Range, End

'

'

'

'

'

'

'

24-Sep-18

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Basis Spread on Variable Rate

550.00%

'

'

'

'

'

'

'

'

92.50%

170.00%

70.00%

50.00%

120.00%

'

'

'

'

'

'

92.50%

170.00%

'

'

'

'

'

95.00%

195.00%

'

'

'

'

'

'

'

'

'

40.00%

45.00%

30.00%

15.00%

120.00%

65.00%

170.00%

115.00%

205.00%

115.00%

205.00%

Senior Notes Due Twenty Twenty Exchange Date

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2011-01-12

'

'

'

'

'

'

'

'

'

'

Line of Credit Facility, Unused Capacity, Commitment Fee Percentage

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

12.50%

30.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair Value Inputs, Cap Rate

'

'

'

'

'

'

'

'

'

'

'

'

'

'

7.25%

6.25%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Inception Date

'

'

'

25-Sep-13

1-Oct-13

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Notional Amount

'

'

565,190,000

'

200,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

100,000,000

'

'

200,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Fixed Interest Rate

'

'

'

'

0.70%

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

0.00%

0.00%

'

'

0.00%

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Number Of Years

'

'

'

3

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

5

5

'

'

5

'

'

'

'

'

'

'

'

'

'

'

'

'

Principal Balance

2,664,834,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

698,048,000

567,527,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unsecured Senior Term Loan Maximum Borrowing Capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

500,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unsecured Term Loans

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$758,786,000

$405,456,000

'

'

'

'

'

'

$165,190,000

[3]

'

$161,860,000

[3]

$350,000,000

[1]

$243,596,000

[3]

$243,596,000

[3]

'

'

'

'

'

'

'

'

'

'

'

'

[1]

In September 2013, the Operating Partnership amended and restated its unsecured credit agreement, providing for aggregate borrowing of up to $1.25 billion, consisting of an unsecured line of credit of $900.0 million and a term loan of $350.0 million (the Term Loan due 2018). In connection with the amendment and restatement of the credit agreement, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.

[2]

At DecemberB 31, 2013, the Operating Partnership had additional borrowing capacity under the unsecured line of credit of up to approximately $772.0 million.

[3]

In August 2012, the Operating Partnership converted approximately $156.4 million of outstanding borrowings into British pounds sterling (bGBPb) equal to £100.0 million, which was designated as a net investment hedge to mitigate the risk of fluctuations in foreign currency exchange rates. The principal balance represents the U.S. dollar amount based on the exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at DecemberB 31, 2013 and DecemberB 31, 2012, respectively. The effective interest rate includes the impact of interest rate swap agreements (see Note 9 for further discussion of interest rate swap agreements).

Debt_Summary_of_the_Operating_

Debt (Summary of the Operating Partnership's Outstanding Consolidated Debt) (Details)

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Sep. 30, 2011

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

USD ($)

USD ($)

Unsecured Senior Notes Due Twenty Twenty [Member]

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Mortgage Notes Payable

Exchangeable Senior Notes

Exchangeable Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Senior Notes

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Line of Credit

Unsecured Line of Credit and Term Loan

Unsecured Line of Credit and Term Loan

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan USD Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan GBP Portion [Member]

Unsecured Term Loan Due 2018 [Member]

USD ($)

USD ($)

9900 Belward Campus Drive

9900 Belward Campus Drive

9901 Belward Campus Drive

9901 Belward Campus Drive

Center for Life Science Boston

Center for Life Science Boston

4320 Forest Park Avenue

Hershey Center for Applied Research

500 Kendall Street (Kendall D)

500 Kendall Street (Kendall D)

Shady Grove Road

Shady Grove Road

University of Maryland BioPark I

University of Maryland BioPark II

University of Maryland BioPark Garage

University of Miami Life Science & Technology Park

USD ($)

USD ($)

USD ($)

USD ($)

Unsecured Senior Notes Due Twenty Sixteen [Member]

Unsecured Senior Notes Due Twenty Sixteen [Member]

Unsecured Senior Notes Due Twenty Twenty [Member]

Unsecured Senior Notes Due Twenty Twenty [Member]

Unsecured Senior Notes Due Twenty Twenty-Two [Member]

Unsecured Senior Notes Due Twenty Twenty-Two [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

Unsecured Term Loans

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD

GBP [Member]

USD ($)

USD ($)

GBP (£)

Debt Instruments

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Stated Interest Rate

6.50%

'

6.13%

'

'

5.64%

'

5.64%

'

7.75%

'

4.00%

[1]

6.15%

[1]

6.38%

'

5.97%

'

5.93%

[1]

5.20%

[1]

5.20%

[1]

4.00%

[1]

3.75%

'

'

'

3.85%

'

6.13%

'

4.25%

'

'

'

'

'

'

1.46%

[2],[3]

'

'

'

1.82%

[4]

'

'

'

2.14%

[4]

'

'

'

1.67%

[2]

Effective Interest Rate

'

'

'

'

'

3.99%

'

3.99%

'

7.75%

'

2.70%

[1]

4.71%

[1]

5.45%

'

5.97%

'

4.69%

[1]

4.33%

[1]

4.33%

[1]

2.89%

[1]

3.75%

'

'

'

3.99%

'

6.27%

'

4.36%

'

'

'

'

'

'

1.46%

[2],[3]

'

'

'

2.63%

[4]

'

'

'

2.39%

[4]

'

'

'

1.97%

[2]

Principal Balance

$2,664,834,000

'

'

$698,048,000

$567,527,000

$10,631,000

$10,767,000

$13,091,000

$13,260,000

$334,447,000

$338,447,000

$21,000,000

[1]

$13,449,000

[1]

$57,927,000

$60,164,000

$143,067,000

$144,889,000

$16,752,000

[1]

$62,946,000

[1]

$4,738,000

[1]

$20,000,000

[1]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unamortized Premiums

'

'

'

11,276,000

4,125,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Mortgage Notes Payable, net

'

'

'

709,324,000

571,652,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Exchangeable Senior Notes

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

180,000,000

180,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unsecured Senior Notes

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

900,000,000

900,000,000

400,000,000

400,000,000

250,000,000

250,000,000

250,000,000

250,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unamortized Discounts

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

-4,917,000

-5,823,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unsecured Senior Notes, net

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

895,083,000

894,177,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Unsecured Term Loans

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

758,786,000

405,456,000

'

'

'

'

'

'

243,596,000

[4]

243,596,000

[4]

'

'

165,190,000

[4]

161,860,000

[4]

156,400,000

[4]

100,000,000

[4]

350,000,000

[2]

Unsecured Line of Credit

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

128,000,000

[2],[3]

118,000,000

[2],[3]

'

'

'

'

'

'

'

'

'

'

'

Total Consolidated Debt

2,671,193,000

2,169,285,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Maturity Date

'

'

'

'

'

1-Jul-17

'

1-Jul-17

'

30-Jun-14

'

30-Jun-15

[1]

5-May-27

[1]

1-Dec-18

'

1-Sep-16

'

15-May-25

[1]

5-Sep-21

[1]

1-Sep-21

[1]

1-Feb-16

[1]

15-Jan-30

'

'

'

15-Apr-16

'

15-Apr-20

'

15-Jul-22

'

'

30-Mar-17

'

'

'

24-Mar-18

[2],[3]

'

24-Mar-18

'

30-Mar-17

[4]

'

'

'

30-Mar-17

[4]

'

'

'

24-Mar-18

[2]

Foreign Currency Exchange Rate, Translation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1.65

1.62

'

'

'

'

'

Debt Instrument, Issuance Date

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

11-Jan-10

'

'

'

30-Mar-11

'

29-Apr-10

'

28-Jun-12

'

30-Mar-12

'

'

'

14-Jul-11

'

'

24-Sep-13

'

'

'

'

'

'

'

'

'

'

Debt Instrument, Face Amount

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

400,000,000

'

250,000,000

'

250,000,000

'

'

400,000,000

'

'

'

900,000,000

'

'

1,250,000,000

'

'

'

'

'

'

'

'

'

Amortization of Financing Costs

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

462,500

'

'

'

'

'

'

'

'

'

'

'

'

'

'

LOC Remaining Borrowing Capacity

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$772,000,000

'

'

'

'

'

'

'

'

'

[1]

Mortgage notes which were assumed on May 31, 2013 in connection with the Companybs merger with Wexford.

[2]

In September 2013, the Operating Partnership amended and restated its unsecured credit agreement, providing for aggregate borrowing of up to $1.25 billion, consisting of an unsecured line of credit of $900.0 million and a term loan of $350.0 million (the Term Loan due 2018). In connection with the amendment and restatement of the credit agreement, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.

[3]

At DecemberB 31, 2013, the Operating Partnership had additional borrowing capacity under the unsecured line of credit of up to approximately $772.0 million.

[4]

In August 2012, the Operating Partnership converted approximately $156.4 million of outstanding borrowings into British pounds sterling (bGBPb) equal to £100.0 million, which was designated as a net investment hedge to mitigate the risk of fluctuations in foreign currency exchange rates. The principal balance represents the U.S. dollar amount based on the exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at DecemberB 31, 2013 and DecemberB 31, 2012, respectively. The effective interest rate includes the impact of interest rate swap agreements (see Note 9 for further discussion of interest rate swap agreements).

Debt_Principal_Payments_Due_fo

Debt (Principal Payments Due for Operating Partnership's Consolidated Indebtedness) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Year 1	$341,416		'
Year 2	30,006		'
Year 3	566,516		'
Year 4	439,080		'
Year 5	523,663		'
Thereafter	764,153	[1]	'
Principal Balance	2,664,834		'
Exchangeable Senior Notes	'		'
Exchangeable Senior Notes	$180,000		$180,000
Maturity Date	15-Jan-30		'
[1]	Includes $180.0 million in principal payments of the Exchangeable Senior Notes based on a contractual maturity date of JanuaryB 15, 2030.

Earnings_Per_Share_of_the_Pare2

Earnings Per Share of the Parent Company (Narrative) (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
BIOMED REALTY, L.P.	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share	'	'	'
Exchangeable Senior Notes Due 2030	10,405,224	10,259,496	10,017,858
Parent Company	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share	'	'	'
Exchangeable Senior Notes Due 2030	10,405,224	10,259,496	10,017,858

Earnings_Per_Share_of_the_Pare3

Earnings Per Share of the Parent Company (Schedule of Earnings Per Share, Basic and Diluted) (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Share data, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Schedule of Earnings Per Share Basic and Diluted

'

'

'

'

'

'

'

'

'

'

'

Income / (loss) from discontinued operations

'

'

'

'

'

'

'

'

$0

($4,370)

$474

Parent Company

'

'

'

'

'

'

'

'

'

'

'

Schedule of Earnings Per Share Basic and Diluted

'

'

'

'

'

'

'

'

'

'

'

Income from continuing operations and noncontrolling interests

'

'

'

'

8,260

[1]

6,455

[1]

-5,283

[1]

6,702

[1]

47,209

16,133

42,240

Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest

'

'

'

'

'

'

'

'

-565

-20

-515

Preferred Stock Dividends and Other Adjustments

'

'

'

'

'

'

'

'

-2,393

-14,603

-16,033

Cost On Redemption Of Preferred Stock

'

'

'

'

'

'

'

'

-6,531

'

-165

Participating Securities, Distributed and Undistributed Earnings

'

'

'

'

'

'

'

'

-1,350

-1,300

-1,172

Income (Loss) from Continuing Operations Attributable to Parent

'

'

'

'

'

'

'

'

36,370

210

24,355

Income / (loss) from discontinued operations

'

'

'

'

0

[1]

0

[1]

49

[1]

-4,420

[1]

'

-4,370

474

Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Noncontrolling Interest

'

'

'

'

'

'

'

'

'

82

-10

Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent

'

'

'

'

'

'

'

'

'

-4,288

464

Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest diluted

'

'

'

'

'

'

'

'

0

-82

10

Income Loss From Discontinued Operations Net Of Tax Diluted

'

'

'

'

'

'

'

'

0

-4,370

474

Net Income (Loss) Available to Common Stockholders, Basic

'

'

'

'

'

'

'

'

36,370

-4,078

24,819

Income (loss) from continuing operations attributable to noncontrollinginterests diluted

'

'

'

'

'

'

'

'

819

29

559

Income from continuing operations attributable to common stockholders - diluted

'

'

'

'

'

'

'

'

37,189

239

24,914

Net Income (Loss) Available to Common Stockholders, Diluted

'

'

'

'

'

'

'

'

$37,189

($4,131)

$25,388

Weighted Average Number of Shares Outstanding, Basic

'

'

'

'

'

'

'

'

182,043,391

152,752,086

132,625,915

Amount of Dilutive Securities Performance Units

'

'

'

'

'

'

'

'

63,017

'

'

Amount Of Dilutive Securities Operating Partnership And Ltip Units

'

'

'

'

'

'

'

'

4,290,614

2,948,301

2,983,928

Basic and Diluted

'

'

'

'

'

'

'

'

186,397,022

155,700,387

135,609,843

Income (Loss) from Continuing Operations, Per Basic and Diluted Share

'

'

'

'

'

'

'

'

$0.20

'

$0.19

Income (Loss) from Discontinued Operations, Net of Tax, Per Basic and Diluted Share

'

'

'

'

$0.03

[1]

$0.02

[1]

($0.06)

[1]

$0.02

[1]

'

($0.03)

'

Earnings Per Share, Basic and Diluted

$0.05

[1]

$0.02

[1]

$0.08

[1]

$0.05

[1]

$0.03

[1]

$0.02

[1]

($0.06)

[1]

($0.01)

[1]

$0.20

($0.03)

$0.19

[1]

The sum of quarterly financial data may vary from the annual data due to rounding.

Earnings_Per_Unit_of_the_Opera2

Earnings Per Unit of the Operating Partnership Earnings Per Unit of the Operating Partnership (Narrative) (Details) (BIOMED REALTY, L.P.)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
BIOMED REALTY, L.P.	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share	'	'	'
Exchangeable Senior Notes Due 2030	10,405,224	10,259,496	10,017,858

Earnings_Per_Unit_of_the_Opera3

Earnings Per Unit of the Operating Partnership (Computations of Basic and Diluted Earnings Per Unit) (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Share data, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Earnings Per Unit of the Operating Partnership

'

'

'

'

'

'

'

'

'

'

'

Income / (loss) from discontinued operations

'

'

'

'

'

'

'

'

$0

($4,370)

$474

BIOMED REALTY, L.P.

'

'

'

'

'

'

'

'

'

'

'

Earnings Per Unit of the Operating Partnership

'

'

'

'

'

'

'

'

'

'

'

Income from continuing operations and noncontrolling interests

'

'

'

'

8,260

[1]

6,455

[1]

-5,283

[1]

6,702

[1]

47,209

16,133

42,240

Income (Loss) from Continuing Operations Attributable to Noncontrolling Interest

'

'

'

'

'

'

'

'

254

8

44

Preferred Stock Dividends and Other Adjustments

'

'

'

'

'

'

'

'

-2,393

-14,603

-16,033

Cost On Redemption Of Preferred Stock

'

'

'

'

'

'

'

'

-6,531

'

-165

Participating Securities, Distributed and Undistributed Earnings

'

'

'

'

'

'

'

'

-1,354

-1,326

-1,220

Income (Loss) from Continuing Operations Attributable to Parent

'

'

'

'

'

'

'

'

37,185

212

24,866

Income / (loss) from discontinued operations

'

'

'

'

'

'

49

[1]

-4,420

[1]

'

-4,370

474

Net Income Loss Attributable To Unit Holders Basic and Diluted

'

'

'

'

'

'

'

'

$37,185

($4,158)

$25,340

Weighted Average Number of Shares Outstanding, Basic

'

'

'

'

'

'

'

'

186,333,292

155,670,931

135,549,934

Amount of Dilutive Securities Performance Units

'

'

'

'

'

'

'

'

63,017

'

'

Basic and Diluted

'

'

'

'

'

'

'

'

186,396,309

155,670,931

135,549,934

Income (Loss) from Continuing Operations, Per Basic and Diluted Share

'

'

'

'

'

'

'

'

$0.20

'

$0.19

Income (Loss) from Discontinued Operations, Net of Tax, Per Basic and Diluted Share

'

'

'

'

$0.03

[1]

$0.02

[1]

($0.06)

[1]

$0.02

[1]

'

($0.03)

'

Net Income per Unit Attributable to Unitholders, Basic and Diluted

$0.05

[1]

$0.02

[1]

$0.08

[1]

$0.05

[1]

$0.03

[1]

$0.02

[1]

($0.06)

[1]

($0.01)

[1]

$0.20

($0.03)

$0.19

[1]

The sum of quarterly financial data may vary from the annual data due to rounding.

Investment_in_Unconsolidated_P2

Investment in Unconsolidated Partnerships (Narrative) (Details)	Dec. 31, 2013
	PREI_LLCs
Equity Method Investments and Joint Ventures [Abstract]	'
Number of Investments in Limited Liability Companies	2

Investment_in_Unconsolidated_P3

Investment in Unconsolidated Partnerships (Summary of Unconsolidated Partnerships) (Details) (USD $)

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

In Millions, unless otherwise specified

PREI I LLC

PREI I LLC

PREI II LLC

PREI II LLC

McKellar Court

McKellar Court

BioPark Fremont

BioPark Fremont

properties

Investment In Unconsolidated Partnerships

'

'

'

'

'

'

'

'

'

'

Equity Method Investment, Ownership Percentage

100.00%

100.00%

'

20.00%

[1]

'

20.00%

'

22.00%

[2]

'

50.00%

[3]

Company's Economic Interest

'

'

'

20.00%

[1]

'

20.00%

'

22.00%

[2]

'

50.00%

[3]

Date Acquired

'

'

4-Apr-07

[1]

'

4-Apr-07

'

30-Sep-04

[2]

'

31-May-13

[3]

'

Number Of Properties In Portfolio Of Prei I Llc

'

'

'

2

'

'

'

'

'

'

Line of Credit Facility, Amount Outstanding

'

'

'

$139

'

'

'

'

'

'

Line Of Credit Facility Weighted Average Interest Rate

'

'

'

3.17%

'

'

'

'

'

'

Line of Credit Facility, Expiration Date

'

'

'

13-Aug-14

'

'

'

'

'

'

Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount

'

'

'

'

'

'

'

$12

'

'

Percent Of Extraordinary Cash Flow Entitled From Variable Interest Entity

'

'

'

'

'

'

'

75.00%

'

'

Percent Of Operating Cash Flows Entitled From Variable Interest Entity

'

'

'

'

'

'

'

22.00%

'

'

[1]

PREI I LLC owns two properties in Cambridge, Massachusetts. At DecemberB 31, 2013, there were $139.0 million in outstanding borrowings on a secured loan facility held by a wholly-owned subsidiary of PREI I LLC, with a contractual interest rate of 3.17% (including the applicable credit spread) and a maturity date of AugustB 13, 2014.

[2]

The Companybs investment in the McKellar Court partnership (maximum exposure to losses) was approximately $12.0 million at DecemberB 31, 2013. The Companybs economic interest in the McKellar Court partnership entitles it to 75% of the extraordinary cash flows after repayment of the partnersb capital contributions and 22% of the operating cash flows.

[3]

The Company's partnership interest was acquired in connection with the Company's merger with Wexford.

Investment_in_Unconsolidated_P4

Investment in Unconsolidated Partnerships (Summary of Selected Balance Sheet Information) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Equity Method Investments and Joint Ventures [Abstract]	'	'
Investments in real estate, net	$262,753	$257,666
Cash and cash equivalents (including restricted cash)	3,855	1,968
Other assets	5,301	4,370
Total assets	271,909	264,004
Mortgage notes payable and secured loan	151,968	149,255
Other liabilities	12,102	5,988
Members' equity	107,839	108,761
Total liabilities and equity	271,909	264,004
Company's net investment in unconsolidated partnerships	$32,137	$32,367

Investment_in_Unconsolidated_P5

Investment in Unconsolidated Partnerships (Summary of Selected Income Statement Information) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Equity Method Investments and Joint Ventures [Abstract]	'		'		'
Total revenues	$12,930		$8,823		$8,567
Total expenses	-21,589		-19,939		-19,868
Loss from continuing operations	-8,659		-11,116		-11,301
EquityMethodInvestmentSummarizedFinancialInformationGainonSaleFromDiscontinuedOperations	'		'		22,927	[1]
Equity Method Investment Summarized Financial Information Loss from Discontinued Operations	'		'		-6,677
Equity Method Investment, Summarized Financial Information, Net Income (Loss)	-8,659		-11,116		4,949
Company's equity in net loss of unconsolidated partnerships	-905		-1,389		-2,489
Fees earned by the Company	$260	[2]	$90	[2]	$1,117	[2]
[1]	During the year ended DecemberB 31, 2011, PREI I LLC recorded a gain on sale of discontinued operations upon sale of certain properties to the Company. In accordance with the equity method of accounting, the Company's share of the equity in net income in PREI I LLC excludes any gain on sale since such gain was generated upon sale of the properties to the Company. The Company recorded a gain on revaluation of the acquired unconsolidated partnership.
[2]	The Company acts as the operating member or partner, as applicable, and day-to-day manager for the partnerships. The Company is entitled to receive fees for providing construction and development services (as applicable) and management services to the PREI joint ventures, which are reflected in tenant recoveries and other income in the consolidated statements of operations.

Derivatives_and_Other_Financia2

Derivatives and Other Financial Instruments (Narrative) (Details)

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2013

USD ($)

USD ($)

USD ($)

InterestRateSwaps [Member]

InterestRateSwaps [Member]

InterestRateSwaps [Member]

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Forward Starting Swaps

Forward Starting Swaps

Forward Starting Swaps

Interest Rate Swaps - $200M [Member]

Interest Rate Swaps - $200M [Member]

Interest Rate Swaps - 100M GBP [Member]

Interest Rate Swaps - $200M (2)

Interest Rate Swaps - $200M (2)

Interest Rate Swap - 150M [Member]

Interest Rate Swap - 115M [Member]

Interest Rate Swap - 35M [Member]

Interest Rate Swap - 35M [Member]

GBP [Member]

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

InterestRateSwaps [Member]

Interest Rate Swaps

InterestRateSwaps [Member]

Interest Rate Swaps

Interest Rate Swaps

InterestRateSwaps [Member]

InterestRateSwaps [Member]

InterestRateSwaps [Member]

InterestRateSwaps [Member]

Interest Rate Swaps - 100M GBP [Member]

USD ($)

USD ($)

GBP_interest_rate_swaps

USD ($)

USD ($)

USD ($)

USD ($)

USD ($)

InterestRateSwaps [Member]

USD_interest_rate_swaps

USD_interest_rate_swaps

GBP (£)

Derivative

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Maturity Date

1-Aug-11

'

'

'

'

'

'

'

'

'

'

'

'

30-Mar-17

'

'

1-Oct-16

'

'

'

'

'

Derivative, Gain (Loss) on Derivative, Net

$416,000

($9,000)

($544,000)

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Inception Date

'

'

'

'

'

'

'

'

'

'

'

'

30-Mar-12

30-Mar-12

2-Aug-12

25-Sep-13

1-Oct-13

'

'

'

'

'

Number Of Interest Rate Swaps

'

'

'

'

'

'

'

'

'

'

'

'

4

'

2

'

'

'

'

'

'

'

Derivative, Number of Instruments Held

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3

'

'

'

'

'

Derivative, Notional Amount

'

'

'

'

'

'

565,190,000

'

'

'

'

'

200,000,000

200,000,000

'

'

200,000,000

150,000,000

115,000,000

'

35,000,000

100,000,000

Derivative, Gain on Derivative

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

12,000

'

'

Accumulated other comprehensive loss, net

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

1,000,000

'

Period Swaps Effectively Fix Interest Rate

'3 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Deferred Interest Costs

'

'

'

'

'

'

'

'

'

35,400,000

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Lower Remaining Maturity Range

'

'

'

'

'

'

'

'

'

'10 years

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Deferred Interest Costs Amortization Period

'5 years

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other Income

-9,451,000

-8,511,000

-10,412,000

'

'

'

-2,619,000

-1,578,000

-3,385,000

-6,832,000

-6,933,000

-7,027,000

'

'

'

'

'

'

'

'

'

'

Reclassification of Accumulated Other Comprehensive Loss

9,900,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative Instruments Deferred Settlement Payments

'

'

'

$326,000

$118,000

$236,000

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivatives_and_Other_Financia3

Derivatives and Other Financial Instruments (Summary of Derivative Instruments) (Details) (USD $)

12 Months Ended

12 Months Ended

3 Months Ended

12 Months Ended

12 Months Ended

In Thousands, unless otherwise specified

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Sep. 30, 2013

Dec. 31, 2013

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Unsecured Term Loan Due 2017 GBP Portion

Unsecured Term Loan Due 2017 GBP Portion

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps

Interest Rate Swaps - $200M (1)

Interest Rate Swaps - $200M (1)

Interest Rate Swaps - $200M (2)

Interest Rate Swaps - $200M (2)

Interest Rate Swap - 50M GBP (1)

Interest Rate Swap - 50M GBP (1)

Interest Rate Swap - 50M GBP (2)

Interest Rate Swap - 50M GBP (2)

Derivative

'

'

'

'

'

'

'

'

'

'

'

'

'

Derivative, Notional Amount

'

'

'

$565,190

'

$200,000

'

'

$200,000

$82,595

[1]

'

$82,595

[1]

'

Derivative, Fixed Interest Rate

'

'

'

'

'

1.16%

'

'

0.70%

0.73%

[1]

'

0.74%

[1]

'

Derivative, Effective Date

'

'

'

'

'

30-Mar-12

'

25-Sep-13

1-Oct-13

2-Aug-12

[1]

'

2-Aug-12

[1]

'

Derivative, Maturity Date

1-Aug-11

'

'

'

'

30-Mar-17

'

'

1-Oct-16

30-Mar-17

[1]

'

30-Mar-17

[1]

'

Derivative, Fair Value, Net

'

'

'

$900

[2]

($5,285)

[2]

($1,876)

[2]

($4,826)

[2]

'

($288)

[2]

$1,545

[1],[2]

($216)

[1],[2]

$1,519

[1],[2]

($243)

[1],[2]

Foreign Currency Exchange Rate, Translation

'

1.65

1.62

'

'

'

'

'

'

'

'

'

'

[1]

Translation to U.S. dollars is based on exchange rates of $1.65 to £1.00 and $1.62 to £1.00 at DecemberB 31, 2013 and DecemberB 31, 2012

[2]

Fair-value of derivative instruments does not include any related accrued interest payable, which is included in accrued expenses on the accompanying consolidated balance sheets. Derivative valuations are classified in Level 2 of the fair-value hierarchy. Assets are included in other assets and liabilities are included in accounts payable, accrued expenses and other liabilities on the accompanying consolidated balance sheets.

Derivatives_and_Other_Financia4

Derivatives and Other Financial Instruments (Summary of Derivative Instruments, Effect on OCI) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Derivative	'	'	'
Other Income	($9,451,000)	($8,511,000)	($10,412,000)
Derivative, Gain (Loss) on Derivative, Net	416,000	-9,000	-544,000
Interest Rate Swaps	'	'	'
Derivative	'	'	'
Other Income	-2,619,000	-1,578,000	-3,385,000
Forward Starting Swaps	'	'	'
Derivative	'	'	'
Other Income	-6,832,000	-6,933,000	-7,027,000
Effective Interest Rate Swaps [Member]	'	'	'
Derivative	'	'	'
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	'	'	-544,000
InterestRateSwaps [Member]	'	'	'
Derivative	'	'	'
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	'	'	-544,000
Parent Company	'	'	'
Derivative	'	'	'
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	12,963,000	'	'
Parent Company | Interest Rate Swaps	'	'	'
Derivative	'	'	'
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	'	($6,863,000)	($104,000)

FairValue_of_Financial_Instrum2

Fair-Value of Financial Instruments (Fair-Value and Carrying Value of the Company's Financial Instruments) (Details) (USD $)	Dec. 31, 2013		Dec. 31, 2012
In Thousands, unless otherwise specified
Fair-Value of Financial Instruments	'		'
Available-for-sale securities	$19,566	[1]	$390	[1]
Unsecured Term Loan Due 2017 GBP Portion	'		'
Fair-Value of Financial Instruments	'		'
Foreign Currency Exchange Rate, Translation	1.65		1.62
Mortgage Notes Payable	'		'
Fair-Value of Financial Instruments	'		'
Mortgage notes payable, net	709,324		571,652
Exchangeable Senior Notes	'		'
Fair-Value of Financial Instruments	'		'
Exchangeable senior notes	180,000		180,000
Unsecured Senior Notes	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	895,083		894,177
Unsecured Line of Credit	'		'
Fair-Value of Financial Instruments	'		'
Unsecured line of credit	128,000	[2],[3]	118,000	[2],[3]
Fair-Value	'		'
Fair-Value of Financial Instruments	'		'
Derivative Instruments	'		5,285
Available-for-sale securities	19,566	[4]	390	[4]
Fair-Value | Mortgage Notes Payable	'		'
Fair-Value of Financial Instruments	'		'
Mortgage notes payable, net	730,394	[4]	605,948	[4]
Fair-Value | Exchangeable Senior Notes	'		'
Fair-Value of Financial Instruments	'		'
Exchangeable senior notes	202,626	[4]	209,484	[4]
Fair-Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Sixteen [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	417,040	[4]	421,400	[4]
Fair-Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Twenty [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	275,600	[4]	292,725	[4]
Fair-Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Twenty-Two [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	240,400	[4]	261,750	[4]
Fair-Value | Unsecured Term Loans | Unsecured Term Loan USD Portion [Member] | USD	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	244,751	[4]	243,596	[4]
Fair-Value | Unsecured Term Loans | Unsecured Term Loan Due 2017 GBP Portion | GBP [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	165,969	[4],[5]	161,860	[4],[5]
Fair-Value | Unsecured Term Loans | Unsecured Term Loan Due 2018 [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	350,000	[4]	'
Fair-Value | Unsecured Line of Credit	'		'
Fair-Value of Financial Instruments	'		'
Unsecured line of credit	128,000	[4]	118,000	[4]
Carrying Value	'		'
Fair-Value of Financial Instruments	'		'
Derivative Instruments	-1,316		'
Available-for-sale securities	19,566		390
Carrying Value | Mortgage Notes Payable	'		'
Fair-Value of Financial Instruments	'		'
Mortgage notes payable, net	709,324		571,652
Carrying Value | Exchangeable Senior Notes	'		'
Fair-Value of Financial Instruments	'		'
Exchangeable senior notes	180,000		180,000
Carrying Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Sixteen [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	398,787		398,289
Carrying Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Twenty [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	248,210		247,984
Carrying Value | Unsecured Senior Notes | Unsecured Senior Notes Due Twenty Twenty-Two [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior notes, net	248,086		247,904
Carrying Value | Unsecured Term Loans | Unsecured Term Loan USD Portion [Member] | USD	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	243,596		243,596
Carrying Value | Unsecured Term Loans | Unsecured Term Loan Due 2017 GBP Portion | GBP [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	165,190	[5]	161,860	[5]
Carrying Value | Unsecured Term Loans | Unsecured Term Loan Due 2018 [Member]	'		'
Fair-Value of Financial Instruments	'		'
Unsecured senior term loans	350,000		'
Carrying Value | Unsecured Line of Credit	'		'
Fair-Value of Financial Instruments	'		'
Unsecured line of credit	$128,000		$118,000
[1]	Determination of fair-value is classified as Level 1 in the fair-value hierarchy based on the use of quoted prices in active markets.
[2]	In September 2013, the Operating Partnership amended and restated its unsecured credit agreement, providing for aggregate borrowing of up to $1.25 billion, consisting of an unsecured line of credit of $900.0 million and a term loan of $350.0 million (the Term Loan due 2018). In connection with the amendment and restatement of the credit agreement, unamortized loan fees under the previous credit agreement of approximately $462,500 were charged to interest expense.
[3]	At DecemberB 31, 2013, the Operating Partnership had additional borrowing capacity under the unsecured line of credit of up to approximately $772.0 million.
[4]	Fair-values of debt and derivative instruments are classified in Level 2 of the fair-value hierarchy. Fair-value of available-for-sale securities are classified in Level 1 of the fair-value hierarchy.
[5]	The principal balance represents the U.S. dollar amount based on the exchange rate of $1.65 to £1.00 and $1.62 to £1.00 at DecemberB 31, 2013 and DecemberB 31, 2012, respectively.

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013
Business Acquisition	'
Real Estate Investments, Net	$162,699,000
Deferred Costs and Other Assets	4,300,000
Tax credits, net of costs and estimated put payments	34,400,000
Tax Credits Delivered	22,400,000
Revenues	45,300,000
Net income / (loss)	-2,600,000
Historic and New Market Tax Credits	'
Business Acquisition	'
Syndicated Historic Tax Credits and New Market Tax Credits	7
Historic Tax Credits	'
Business Acquisition	'
Percentage of Qualified Investments	39.00%
Percentage of Tax Credit Recapture	20.00%
New Market Tax Credits	'
Business Acquisition	'
Percentage of Tax Credit Recapture	100.00%
Historical Tax Credit Recapture Period	'1 year
Chesterfield [Member] [Domain]	'
Business Acquisition	'
Square Footage of Real Estate Property	274,000
Real Estate Investments, Net	$13,383,000
ThreeEleven South Sarah [Member] [Domain]	'
Business Acquisition	'
Square Footage of Real Estate Property	300,000

Acquisitions_Schedule_of_Purch

Acquisitions (Schedule of Purchase Price Allocation - excluding Merger) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition	'	'
Business Acquisition, Effective Date of Acquisition	'	5-Sep-07
Business Acquisition, Purchase Price Allocation, Property	$162,699	'
Business Acquisition, Cost of Acquired Entity, Cash Paid	173,518	'
Woodside Technology Park	'	'
Business Acquisition	'	'
Business Acquisition, Description of Acquired Entity	'Woodside Technology Park	'
Business Acquisition, Effective Date of Acquisition	28-Feb-13	'
Business Acquisition, Purchase Price Allocation, Property	78,681	'
Business Acquisition, Cost of Acquired Entity, Cash Paid	87,000	'
The Campus at Lincoln Centre	'	'
Business Acquisition	'	'
Business Acquisition, Description of Acquired Entity	'The Campus at Lincoln Centre	'
Business Acquisition, Effective Date of Acquisition	20-Mar-13	'
Business Acquisition, Purchase Price Allocation, Property	37,000	'
Business Acquisition, Cost of Acquired Entity, Cash Paid	37,000	'
320 Charles Street	'	'
Business Acquisition	'	'
Business Acquisition, Description of Acquired Entity	'320 Charles Street	'
Business Acquisition, Effective Date of Acquisition	18-Jun-13	'
Business Acquisition, Purchase Price Allocation, Property	47,018	'
Business Acquisition, Cost of Acquired Entity, Cash Paid	49,518	'
Leases, Acquired-in-Place	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	12,740	'
Finite-Lived Intangible Asset, Useful Life	'61 months	'
Leases, Acquired-in-Place | Woodside Technology Park	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	8,162	'
Leases, Acquired-in-Place | 320 Charles Street	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	4,578	'
Acquired Management Agreements	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	865	'
Finite-Lived Intangible Asset, Useful Life	'108 months	'
Acquired Management Agreements | Woodside Technology Park	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	865	'
Leases, Acquired-in-Place, Market Adjustment	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	-2,786	'
Finite-Lived Intangible Asset, Useful Life	'18 months	'
Leases, Acquired-in-Place, Market Adjustment | Woodside Technology Park	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	-708	'
Leases, Acquired-in-Place, Market Adjustment | 320 Charles Street	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	($2,078)	'

Acquisitions_Acquisitions_Sche

Acquisitions Acquisitions (Schedule of Purchase Price Allocation - Merger) (Details) (USD $)	3 Months Ended	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2013
Leases, Acquired-in-Place	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	12,740
Finite-Lived Intangible Asset, Useful Life	'	'61 months
Leases, Acquired-in-Place, Market Adjustment	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	-2,786
Finite-Lived Intangible Asset, Useful Life	'	'18 months
Common Stock	'	'
Business Acquisition	'	'
Stock Issued During Period, Merger Issues	'	5,568,227
Limited Partner | Common Stock	'	'
Business Acquisition	'	'
Stock Issued During Period, Units, Issued in Connection with Wexford Merger	336,960	336,960
Wexford Merger	'	'
Business Acquisition	'	'
Business Acquisition, Purchase Price Allocation, Investments in Real Estate	'	659,517
Business Acquisition, Purchase Price Allocation, Cash and Cash Equivalents	'	5,182
Business Acquisition, Purchase Price Allocation, Accounts Receivable net	'	1,537
Business Acquisition, Purchase Price Allocation, Deferred Leasing Costs	'	52,670
Business Acquisition, Purchase Price Allocation, Other Assets	'	89,631
Business Acquisition, Purchase Price Allocation, Total Assets	'	808,537
Business Acquisition, Purchase Price Allocation, Mortgage Notes Payable	'	254,735
Business Acquisition, Purchase Price Allocation, Other Liabilities	'	69,270
Business Acquisition, Purchase Price Allocation, Total Liabilities	'	324,005
Business Acquisition, Purchase Price Allocation, Fair Value of Net Assets Acquired	'	484,532
Business Acquisition, Cash Consideration Paid for Wexford	'	345,268
Business Acquisition, Equity Consideration Paid for Wexford	'	123,596
Business Acquisition, Contingent Consideration in Merger with Wexford	'	15,668
Business Acquisition, Total Consideration for Wexford	'	484,532
Wexford Merger | Leases, Acquired-in-Place	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	52,700
Finite-Lived Intangible Asset, Useful Life	'	'10 years 11 months
Wexford Merger | Above Market Leases	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	9,600
Finite-Lived Intangible Asset, Useful Life	'	'11 years 7 months
Wexford Merger | Below Market Ground Leases	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	11,000
Finite-Lived Intangible Asset, Useful Life	'	'51 years 8 months
Wexford Merger | Debt Premium	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	-8,700
Finite-Lived Intangible Asset, Useful Life	'	'9 years 2 months 16 days
Wexford Merger | Leases, Acquired-in-Place, Market Adjustment	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	-31,400
Finite-Lived Intangible Asset, Useful Life	'	'13 years 5 months
Wexford Merger | Above Market Ground Leases	'	'
Business Acquisition	'	'
Acquired Finite-lived Intangible Asset, Amount	'	-2,500
Finite-Lived Intangible Asset, Useful Life	'	'64 years 0 months

Acquisitions_Acquisitions_Sele

Acquisitions Acquisitions (Selected Financial Data of the VIEs) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Variable Interest Entity	'	'
Investment in Real Estate, Net	$336,832	$334,331
Total Assets	375,443	369,460
Total Liabilities	154,953	149,336
Wexford Merger	'	'
Variable Interest Entity	'	'
Investment in Real Estate, Net	177,901	'
Total Assets	198,968	'
Total Liabilities	$60,197	'

Acquisitions_Pro_Forma_Results

Acquisitions (Pro Forma Results) (Details) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Parent Company	'	'
Business Acquisition	'	'
Business Acquisition, Pro Forma Revenue	$666,904	$590,415
Business Acquisition, Pro Forma Net Income (Loss)	36,981	-19,493
Business Acquisition Pro Forma Earnings Per Share Basic And Diluted	$0.20	($0.13)
BIOMED REALTY, L.P.	'	'
Business Acquisition	'	'
Business Acquisition, Pro Forma Revenue	666,904	590,415
Business Acquisition, Pro Forma Net Income (Loss)	$37,800	($19,547)
Business Acquisition Pro Forma Earnings Per Share Basic And Diluted	$0.20	($0.13)

Discontinued_Operations_Discon

Discontinued Operations (Discontinued Operations) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012		Dec. 31, 2011
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations	'	'		'
Disposal Group, Including Discontinued Operation, Revenue	$0	$454		$1,499
Disposal Group, Including Discontinued Operation, Operating Expense	0	272		1,025
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax	0	182		474
Date of Sale	'	27-Apr-12		'
Original Acquisition Date	'	5-Sep-07		'
Sales Price	'	28,000	[1]	'
Impairment Loss	0	-4,552		'
Income / (loss) from discontinued operations	0	-4,370		474
Forbes Boulevard	'	'		'
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations	'	'		'
Impairment Loss	'	($4,552)		'
[1]	The sales price was equal to the fair-value of the office property received as consideration in the exchange with the independent third party.

Incentive_Award_Plan_Incentive2

Incentive Award Plan Incentive Award Plan (Narrative) (Details)	12 Months Ended
	Dec. 31, 2013
	runs
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	6,896,224
Approximate Number Of Times Simulation Was Run	100,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	0.35%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate	4.41%
One Year [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	'1 year
Two Years [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	'2 years
Share Based Compensation Arrangement By Share Based Payment Award Vesting Percentage Unvested As Of Date Expected Term	24
Three Years [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	'3 years
Share Based Compensation Arrangement By Share Based Payment Award Vesting Percentage Unvested As Of Date Expected Term	36
Incentive Award Plan [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	10,740,000
BIOMED REALTY, L.P.	'
Incentive Award Plan Selected Data [Line Items]	'
Deferred Compensation Arrangement with Individual, Requisite Service Period	'5
Maximum [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	'5 years
Minimum [Member]	'
Incentive Award Plan Selected Data [Line Items]	'
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	'4 years

Incentive_Award_Plan_Incentive3

Incentive Award Plan Incentive Award Plan (Summary of Unvested Restricted Stock and LTIP Units) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]	'	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	1,512,005	1,560,512	1,721,062	1,588,060
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	657,106	395,350	630,337	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	665,808	520,258	467,120	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	39,805	35,642	30,215	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$18.91	$17	$16.09	$15.15
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$20.33	$18.46	$18.38	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$15.91	$15.17	$16.03	'
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$18.15	$15.97	$16.17	'

Incentive_Award_Plan_Incentive4

Incentive Award Plan Incentive Award Plan (Incentive Award Plan Selected Data) (Details) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	years
Incentive Award Plan [Member]	'	'	'
Incentive Award Plan Selected Data [Line Items]	'	'	'
Share-based Compensation	$13,234	$7,300	$11,612
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	13,321	9,502	8,547
Allocated Share-based Compensation Expense	10,134	9,556	7,582
Shares surrendered to the Company and retired in lieu of cash payments for taxes due on the vesting of restricted stock	253,671,000	178,915,000	129,342,000
Employee Benefits and Share-based Compensation	17,145	'	'
Share Based Compensation Arrangement Recognized Over Weighted Average Period	2.6	'	'
Performance Shares	'	'	'
Incentive Award Plan Selected Data [Line Items]	'	'	'
Share-based Compensation	4,973	3,329	0
Allocated Share-based Compensation Expense	2,445	1,974	'
Employee Benefits and Share-based Compensation	$2,528	'	'
Share Based Compensation Arrangement Recognized Over Weighted Average Period	1.5	'	'

Commitments_and_Contingencies_1

Commitments and Contingencies Commitments and Contingencies (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Commitment And Contingencies [Line Items]	'	'	'
Number Of Years From Initial Public Offering	'10 years	'	'
Construction And Other Related Commitments, Current Fiscal	$415,800,000	'	'
Construction And Other Related Commitments With In One Year	350,500,000	'	'
Construction And Other Related Commitments With In Two Years	64,200,000	'	'
Construction And Other Related Commitments With In Four Years	1,200,000	'	'
Ground Lease Commitments	513,200,000	'	'
Ground lease commitments Within One Year	4,500,000	'	'
Ground Lease Commitments Within Three Years	9,600,000	'	'
Ground Lease Commitments Within Five Years	10,300,000	'	'
Ground Lease Commitments Thereafter	488,800,000	'	'
Minimum Debt Requirement	8,000,000	'	'
Human Genome Sciences Inc [Member]	'	'	'
Commitment And Contingencies [Line Items]	'	'	'
Percentage Of Revenues To Total Rental Revenues	10.80%	12.20%	14.50%
Rental	48,000,000	48,000,000	48,000,000
Vertex Pharmaceuticals Incorporated [Member]	'	'	'
Commitment And Contingencies [Line Items]	'	'	'
Percentage Of Revenues To Total Rental Revenues	7.70%	8.50%	10.00%
Rental	$34,500,000	$33,400,000	$33,200,000

Quarterly_Financial_Informatio4

Quarterly Financial Information of the Parent Company Quarterly Financial Information of the Parent Company (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Per Share data, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Quarterly Financial Information Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenues

'

'

'

'

'

'

'

'

$45,300

'

'

Income / (loss) from discontinued operations

'

'

'

'

'

'

'

'

0

-4,370

474

Net Income (Loss), Including Portion Attributable to Noncontrolling Interest

'

'

'

'

'

'

'

'

-2,600

'

'

Parent Company

'

'

'

'

'

'

'

'

'

'

'

Quarterly Financial Information Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenues

157,993

[1]

159,232

[1]

159,639

[1]

160,450

[1]

138,771

[1]

134,537

[1]

124,848

[1]

120,012

[1]

637,314

518,167

438,200

Income from continuing operations and noncontrolling interests

'

'

'

'

8,260

[1]

6,455

[1]

-5,283

[1]

6,702

[1]

47,209

16,133

42,240

Income / (loss) from discontinued operations

'

'

'

'

0

[1]

0

[1]

49

[1]

-4,420

[1]

'

-4,370

474

Net Income (Loss), Including Portion Attributable to Noncontrolling Interest

10,576

[1]

4,136

[1]

15,037

[1]

17,458

[1]

8,260

[1]

6,455

[1]

-5,234

[1]

2,282

[1]

47,209

11,763

42,714

Net Income (Loss) Attributable to Noncontrolling Interest

-297

[1]

111

[1]

-234

[1]

-146

[1]

-93

[1]

-46

[1]

172

[1]

30

[1]

565

-62

525

Preferred Stock Dividends, Income Statement Impact

0

[1]

0

[1]

0

[1]

-2,393

[1]

-3,651

[1]

-3,651

[1]

-3,651

[1]

-3,651

[1]

2,393

14,603

16,033

Net Income (Loss) Available to Common Stockholders, Basic

$10,279

[1]

$4,247

[1]

$14,803

[1]

$8,388

[1]

$4,516

[1]

$2,758

[1]

($8,713)

[1]

($1,339)

[1]

$37,720

($2,778)

$25,991

Income (Loss) from Discontinued Operations, Net of Tax, Per Basic and Diluted Share

'

'

'

'

$0.03

[1]

$0.02

[1]

($0.06)

[1]

$0.02

[1]

'

($0.03)

'

Earnings Per Share, Basic and Diluted

$0.05

[1]

$0.02

[1]

$0.08

[1]

$0.05

[1]

$0.03

[1]

$0.02

[1]

($0.06)

[1]

($0.01)

[1]

$0.20

($0.03)

$0.19

[1]

The sum of quarterly financial data may vary from the annual data due to rounding.

Quarterly_Financial_Informatio5

Quarterly Financial Information of the Operating Partnership Quarterly Financial Information of the Operating Partnership (Details) (USD $)

3 Months Ended

12 Months Ended

In Thousands, except Per Share data, unless otherwise specified

Dec. 31, 2013

Sep. 30, 2013

Jun. 30, 2013

Mar. 31, 2013

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Quarterly Financial Information Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenues

'

'

'

'

'

'

'

'

$45,300

'

'

Income / (loss) from discontinued operations

'

'

'

'

'

'

'

'

0

-4,370

474

Net Income (Loss), Including Portion Attributable to Noncontrolling Interest

'

'

'

'

'

'

'

'

-2,600

'

'

BIOMED REALTY, L.P.

'

'

'

'

'

'

'

'

'

'

'

Quarterly Financial Information Disclosure [Line Items]

'

'

'

'

'

'

'

'

'

'

'

Revenues

157,993

[1]

159,232

[1]

159,639

[1]

160,450

[1]

138,771

[1]

134,537

[1]

124,848

[1]

120,012

[1]

637,314

518,167

438,200

Income from continuing operations and noncontrolling interests

'

'

'

'

8,260

[1]

6,455

[1]

-5,283

[1]

6,702

[1]

47,209

16,133

42,240

Income / (loss) from discontinued operations

'

'

'

'

'

'

49

[1]

-4,420

[1]

'

-4,370

474

Net Income (Loss), Including Portion Attributable to Noncontrolling Interest

10,576

[1]

4,136

[1]

15,037

[1]

17,458

[1]

8,260

[1]

6,455

[1]

-5,234

[1]

2,282

[1]

47,209

11,763

42,714

Net Income (Loss) Attributable to Noncontrolling Interest

-12

[1]

229

[1]

29

[1]

8

[1]

-7

[1]

7

[1]

6

[1]

4

[1]

-254

-8

-44

Preferred Stock Dividends, Income Statement Impact

'

'

'

-2,393

[1]

-3,651

[1]

-3,651

[1]

-3,651

[1]

-3,651

[1]

2,393

14,603

16,033

Net Income (Loss) Available to Common Stockholders, Basic

$10,564

[1]

$4,365

[1]

$15,066

[1]

$8,542

[1]

$4,602

[1]

$2,811

[1]

($8,879)

[1]

($1,365)

[1]

$38,539

($2,832)

$26,560

Income (Loss) from Discontinued Operations, Net of Tax, Per Basic and Diluted Share

'

'

'

'

$0.03

[1]

$0.02

[1]

($0.06)

[1]

$0.02

[1]

'

($0.03)

'

Earnings Per Share, Basic and Diluted

$0.05

[1]

$0.02

[1]

$0.08

[1]

$0.05

[1]

$0.03

[1]

$0.02

[1]

($0.06)

[1]

($0.01)

[1]

$0.20

($0.03)

$0.19

[1]

The sum of quarterly financial data may vary from the annual data due to rounding.

Schedule_III_Schedule_III_Deta

Schedule III Schedule III (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
In Thousands, unless otherwise specified
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	$684,599	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	816,335	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	14,210	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,803,622	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,366,576	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	833,278	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	5,170,202	'	'	'
SEC Schedule III, Real Estate, Gross	6,003,480	4,923,166	4,402,720	3,878,092
SEC Schedule III, Real Estate Accumulated Depreciation	-785,578	-603,450	-452,474	-341,978
Real Estate Investment Property, Net	5,217,902	4,319,716	'	'
Albany Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,942	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	31,293	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,169	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,942	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	32,462	'	'	'
SEC Schedule III, Real Estate, Gross	34,404	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,788	'	'	'
Real Estate Investment Property, Net	27,616	'	'	'
Ardentech Court [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,742	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,379	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	9,406	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,742	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,785	'	'	'
SEC Schedule III, Real Estate, Gross	17,527	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-5,891	'	'	'
Real Estate Investment Property, Net	11,636	'	'	'
Ardenwood Venture [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,550	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,603	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,376	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,550	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	15,979	'	'	'
SEC Schedule III, Real Estate, Gross	19,529	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,453	'	'	'
Real Estate Investment Property, Net	15,076	'	'	'
Ardsley Park [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	6,581	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	9,479	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	27,559	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,581	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	37,038	'	'	'
SEC Schedule III, Real Estate, Gross	43,619	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,635	'	'	'
Real Estate Investment Property, Net	39,984	'	'	'
Balboa Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,316	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	9,493	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	967	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,316	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,460	'	'	'
SEC Schedule III, Real Estate, Gross	11,776	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,535	'	'	'
Real Estate Investment Property, Net	9,241	'	'	'
Bayshore Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,667	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	22,593	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	7,486	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,667	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	30,079	'	'	'
SEC Schedule III, Real Estate, Gross	33,746	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-10,937	'	'	'
Real Estate Investment Property, Net	22,809	'	'	'
Beckley Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,480	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	17,590	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,480	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	17,590	'	'	'
SEC Schedule III, Real Estate, Gross	19,070	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,976	'	'	'
Real Estate Investment Property, Net	15,094	'	'	'
Bernardo Center Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,580	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	13,714	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	284	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,580	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,998	'	'	'
SEC Schedule III, Real Estate, Gross	16,578	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,096	'	'	'
Real Estate Investment Property, Net	13,482	'	'	'
9900 Belward Campus Drive	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	10,631	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,038	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,274	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	8	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,038	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,282	'	'	'
SEC Schedule III, Real Estate, Gross	10,320	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-453	'	'	'
Real Estate Investment Property, Net	9,867	'	'	'
9901 Belward Campus Drive	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	13,091	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,362	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,185	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,362	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,185	'	'	'
SEC Schedule III, Real Estate, Gross	14,547	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-621	'	'	'
Real Estate Investment Property, Net	13,926	'	'	'
Nine Thousand Nine Hundred And Eleven Belward Campus Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,160	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	196,814	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,160	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	196,814	'	'	'
SEC Schedule III, Real Estate, Gross	200,974	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-38,883	'	'	'
Real Estate Investment Property, Net	162,091	'	'	'
Nine Thousand Nine Hundred And Twenty Belward Campus Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,935	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,206	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,935	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,206	'	'	'
SEC Schedule III, Real Estate, Gross	15,141	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,271	'	'	'
Real Estate Investment Property, Net	12,870	'	'	'
320 Bent Street	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	88,254	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	7,420	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	95,674	'	'	'
SEC Schedule III, Real Estate, Gross	95,674	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-9,760	'	'	'
Real Estate Investment Property, Net	85,914	'	'	'
301 Binney Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	217,073	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,760	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	222,833	'	'	'
SEC Schedule III, Real Estate, Gross	222,833	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-25,610	'	'	'
Real Estate Investment Property, Net	197,223	'	'	'
301 Binney Garage [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,805	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	113	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	15,918	'	'	'
SEC Schedule III, Real Estate, Gross	15,918	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-855	'	'	'
Real Estate Investment Property, Net	15,063	'	'	'
BRDG Park Danforth Plant Science Center [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	31,139	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	31,139	'	'	'
SEC Schedule III, Real Estate, Gross	31,139	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-856	'	'	'
Real Estate Investment Property, Net	30,283	'	'	'
Bridgeview Technology Park One [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,494	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	14,716	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	18,895	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,494	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	33,611	'	'	'
SEC Schedule III, Real Estate, Gross	36,105	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-11,692	'	'	'
Real Estate Investment Property, Net	24,413	'	'	'
Bridgeview Technology Park Two [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,522	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	13,066	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	27	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,522	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,093	'	'	'
SEC Schedule III, Real Estate, Gross	14,615	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,883	'	'	'
Real Estate Investment Property, Net	11,732	'	'	'
210 Broadway [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	6,917	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	16,272	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,442	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,917	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	21,714	'	'	'
SEC Schedule III, Real Estate, Gross	28,631	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,303	'	'	'
Real Estate Investment Property, Net	27,328	'	'	'
550 Broadway [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,700	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	24,300	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,700	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	24,300	'	'	'
SEC Schedule III, Real Estate, Gross	28,000	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,882	'	'	'
Real Estate Investment Property, Net	26,118	'	'	'
Center for Life Science Boston	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	334,447	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	60,000	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	407,747	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	257,664	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	60,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	665,411	'	'	'
SEC Schedule III, Real Estate, Gross	725,411	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-116,658	'	'	'
Real Estate Investment Property, Net	608,753	'	'	'
Charles Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	5,000	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,033	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	57	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,090	'	'	'
SEC Schedule III, Real Estate, Gross	12,090	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,459	'	'	'
Real Estate Investment Property, Net	10,631	'	'	'
320 Charles Street	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	14,020	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	32,998	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	14,020	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	32,998	'	'	'
SEC Schedule III, Real Estate, Gross	47,018	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,174	'	'	'
Real Estate Investment Property, Net	45,844	'	'	'
Chesterfield [Member] [Domain]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,350	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,853	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	63	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,350	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	6,916	'	'	'
SEC Schedule III, Real Estate, Gross	8,266	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	8,266	'	'	'
Coast 9 [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	13,455	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,786	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	20,654	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	13,455	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	33,440	'	'	'
SEC Schedule III, Real Estate, Gross	46,895	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,611	'	'	'
Real Estate Investment Property, Net	42,284	'	'	'
Coolidge Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,760	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,102	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	3,873	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,760	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,975	'	'	'
SEC Schedule III, Real Estate, Gross	13,735	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,905	'	'	'
Real Estate Investment Property, Net	11,830	'	'	'
Dumbarton Circle [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,723	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,097	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	495	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,723	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	5,592	'	'	'
SEC Schedule III, Real Estate, Gross	8,315	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,244	'	'	'
Real Estate Investment Property, Net	5,071	'	'	'
Eccles Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	21,257	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	608	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	9,896	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	21,257	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,504	'	'	'
SEC Schedule III, Real Estate, Gross	31,761	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-608	'	'	'
Real Estate Investment Property, Net	31,153	'	'	'
Elliott Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	10,124	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	38,911	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	62,964	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,124	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	101,875	'	'	'
SEC Schedule III, Real Estate, Gross	111,999	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-13,592	'	'	'
Real Estate Investment Property, Net	98,407	'	'	'
Twenty One Erie Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,366	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	18,372	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	148	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,366	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	18,520	'	'	'
SEC Schedule III, Real Estate, Gross	21,886	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,994	'	'	'
Real Estate Investment Property, Net	17,892	'	'	'
Forty Erie Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,593	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	33,765	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	3,931	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,593	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	37,696	'	'	'
SEC Schedule III, Real Estate, Gross	45,289	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-7,744	'	'	'
Real Estate Investment Property, Net	37,545	'	'	'
Four Thousand Five Hundred And Seventy Executive Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,685	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	48,693	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	328	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,685	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	49,021	'	'	'
SEC Schedule III, Real Estate, Gross	56,706	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-8,211	'	'	'
Real Estate Investment Property, Net	48,495	'	'	'
Four Thousand Seven Hundred And Seventy Five Over Four Thousand Seven Hundred And Eighty Five Executive Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	10,180	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	17,100	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	8,137	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,180	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	25,237	'	'	'
SEC Schedule III, Real Estate, Gross	35,417	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-570	'	'	'
Real Estate Investment Property, Net	34,847	'	'	'
Five Hundred Fairview Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,285	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	3,529	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	6,814	'	'	'
SEC Schedule III, Real Estate, Gross	6,814	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,298	'	'	'
Real Estate Investment Property, Net	3,516	'	'	'
Five Hundred And Thirty Fairview Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,703	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	694	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	46,268	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,703	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	46,962	'	'	'
SEC Schedule III, Real Estate, Gross	49,665	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-11,306	'	'	'
Real Estate Investment Property, Net	38,359	'	'	'
Faraday Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,370	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,201	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,370	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,201	'	'	'
SEC Schedule III, Real Estate, Gross	8,571	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,505	'	'	'
Real Estate Investment Property, Net	7,066	'	'	'
4320 Forest Park Avenue	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	21,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	26,105	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	142	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	26,247	'	'	'
SEC Schedule III, Real Estate, Gross	26,247	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-699	'	'	'
Real Estate Investment Property, Net	25,548	'	'	'
Fresh Pond Research Park [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,500	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	18,322	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	23,523	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,500	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	41,845	'	'	'
SEC Schedule III, Real Estate, Gross	45,345	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,895	'	'	'
Real Estate Investment Property, Net	38,450	'	'	'
Gateway Business Park [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	116,851	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,981	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	7,043	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	116,851	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	18,024	'	'	'
SEC Schedule III, Real Estate, Gross	134,875	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-9,226	'	'	'
Real Estate Investment Property, Net	125,649	'	'	'
Gazelle Court [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	10,100	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	1,769	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	55,893	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,100	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	57,662	'	'	'
SEC Schedule III, Real Estate, Gross	67,762	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,604	'	'	'
Real Estate Investment Property, Net	61,158	'	'	'
George Patterson Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,575	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,029	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	2,044	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,575	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,073	'	'	'
SEC Schedule III, Real Estate, Gross	14,648	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,609	'	'	'
Real Estate Investment Property, Net	12,039	'	'	'
Granta Park [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	34,589	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	152,797	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	34,589	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	152,797	'	'	'
SEC Schedule III, Real Estate, Gross	187,386	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,802	'	'	'
Real Estate Investment Property, Net	180,584	'	'	'
Graphics Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	800	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,577	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	6,941	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	800	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,518	'	'	'
SEC Schedule III, Real Estate, Gross	14,318	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-5,768	'	'	'
Real Estate Investment Property, Net	8,550	'	'	'
Fifty Hampshire [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	19,537	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	58,205	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	185	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	19,537	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	58,390	'	'	'
SEC Schedule III, Real Estate, Gross	77,927	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,445	'	'	'
Real Estate Investment Property, Net	74,482	'	'	'
Sixty Hampshire [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,164	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	78	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,410	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,164	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	1,488	'	'	'
SEC Schedule III, Real Estate, Gross	5,652	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-78	'	'	'
Real Estate Investment Property, Net	5,574	'	'	'
Heritage @ 4240 [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,966	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	18,365	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	31,331	'	'	'
SEC Schedule III, Real Estate, Gross	31,331	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-50	'	'	'
Real Estate Investment Property, Net	31,281	'	'	'
Hershey Center for Applied Research	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	16,736	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,736	'	'	'
SEC Schedule III, Real Estate, Gross	16,736	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-494	'	'	'
Real Estate Investment Property, Net	16,242	'	'	'
Industrial Road [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	12,000	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	41,718	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	16,286	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	12,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	58,004	'	'	'
SEC Schedule III, Real Estate, Gross	70,004	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-22,701	'	'	'
Real Estate Investment Property, Net	47,303	'	'	'
Innovation Research Park at ODU I [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	26,426	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	26,426	'	'	'
SEC Schedule III, Real Estate, Gross	26,426	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-778	'	'	'
Real Estate Investment Property, Net	25,648	'	'	'
Innovation Research Park at ODU II [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	25,297	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	22	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	25,319	'	'	'
SEC Schedule III, Real Estate, Gross	25,319	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-585	'	'	'
Real Estate Investment Property, Net	24,734	'	'	'
Three Thousand Five Hundred And Twenty Five John Hopkins Court [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,993	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	18,183	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	298	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,993	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	18,481	'	'	'
SEC Schedule III, Real Estate, Gross	22,474	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,780	'	'	'
Real Estate Investment Property, Net	20,694	'	'	'
Three Thousand Five Hundred Forty Five To Three Thousand Five Hundred And Seventy Five John Hopkins Court [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,560	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	19,495	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	20,046	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,560	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	39,541	'	'	'
SEC Schedule III, Real Estate, Gross	43,101	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-7,302	'	'	'
Real Estate Investment Property, Net	35,799	'	'	'
Kaiser Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,430	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,093	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	10,391	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,430	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,484	'	'	'
SEC Schedule III, Real Estate, Gross	19,914	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,298	'	'	'
Real Estate Investment Property, Net	15,616	'	'	'
450 Kendall Street (Kendall G) [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,259	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,614	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,873	'	'	'
SEC Schedule III, Real Estate, Gross	13,873	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	13,873	'	'	'
500 Kendall Street (Kendall D)	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	57,927	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,572	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	166,308	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	627	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,572	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	166,935	'	'	'
SEC Schedule III, Real Estate, Gross	170,507	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-36,039	'	'	'
Real Estate Investment Property, Net	134,468	'	'	'
Kendall Crossing Apartments [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,665	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	577	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,242	'	'	'
SEC Schedule III, Real Estate, Gross	7,242	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-502	'	'	'
Real Estate Investment Property, Net	6,740	'	'	'
King Of Prussia Road [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	12,813	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	66,152	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,900	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	12,813	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	68,052	'	'	'
SEC Schedule III, Real Estate, Gross	80,865	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-22,573	'	'	'
Real Estate Investment Property, Net	58,292	'	'	'
Landmark At Eastview [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	14,210	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	55,250	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	249,407	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	16,943	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	304,657	'	'	'
SEC Schedule III, Real Estate, Gross	321,600	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-54,027	'	'	'
Real Estate Investment Property, Net	267,573	'	'	'
The Campus at Lincoln Center [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	37,000	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,281	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	37,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	1,281	'	'	'
SEC Schedule III, Real Estate, Gross	38,281	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	38,281	'	'	'
Thirtyseven Eleven Market Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	85,357	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	879	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	86,236	'	'	'
SEC Schedule III, Real Estate, Gross	86,236	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,008	'	'	'
Real Estate Investment Property, Net	84,228	'	'	'
Thirty Seven Thirty Seven Market Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	24,588	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	31,338	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	55,926	'	'	'
SEC Schedule III, Real Estate, Gross	55,926	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	55,926	'	'	'
Medical Center Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	9,620	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	43,561	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	14,676	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	9,620	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	58,237	'	'	'
SEC Schedule III, Real Estate, Gross	67,857	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-5,506	'	'	'
Real Estate Investment Property, Net	62,351	'	'	'
Monte Villa Parkway [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,020	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,759	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	8,766	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,020	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,525	'	'	'
SEC Schedule III, Real Estate, Gross	15,545	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,787	'	'	'
Real Estate Investment Property, Net	12,758	'	'	'
Six Thousand One Hundred And Fourteen To Six Thousand One Hundred And Fifty Four Nancy Ridge Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	10,100	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	28,611	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	16,378	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	10,100	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	44,989	'	'	'
SEC Schedule III, Real Estate, Gross	55,089	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-7,010	'	'	'
Real Estate Investment Property, Net	48,079	'	'	'
Six thousand one hundred and twenty two NancyRidge [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,344	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	9,611	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,787	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,344	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	11,398	'	'	'
SEC Schedule III, Real Estate, Gross	13,742	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,878	'	'	'
Real Estate Investment Property, Net	10,864	'	'	'
Six Thousand Eight Hundred And Twenty Eight Nancy Ridge Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,174	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,592	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,174	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,592	'	'	'
SEC Schedule III, Real Estate, Gross	14,766	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-654	'	'	'
Real Estate Investment Property, Net	14,112	'	'	'
Science Center at Oyster Point	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	19,464	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	89,762	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,122	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	19,464	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	94,884	'	'	'
SEC Schedule III, Real Estate, Gross	114,348	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-9,700	'	'	'
Real Estate Investment Property, Net	104,648	'	'	'
One Research Way [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,813	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,454	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	6,171	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,813	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,625	'	'	'
SEC Schedule III, Real Estate, Gross	14,438	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,905	'	'	'
Real Estate Investment Property, Net	12,533	'	'	'
Pacific Center Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	5,400	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	11,493	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	3,395	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,400	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,888	'	'	'
SEC Schedule III, Real Estate, Gross	20,288	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,571	'	'	'
Real Estate Investment Property, Net	16,717	'	'	'
Pacific Research Center [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	74,147	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	142,437	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	151,438	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	74,147	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	293,875	'	'	'
SEC Schedule III, Real Estate, Gross	368,022	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-55,555	'	'	'
Real Estate Investment Property, Net	312,467	'	'	'
Three Thousand Five Hundred Paramount Parkway [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,080	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	14,535	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	26	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,080	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,561	'	'	'
SEC Schedule III, Real Estate, Gross	15,641	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,826	'	'	'
Real Estate Investment Property, Net	13,815	'	'	'
Patriot [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	848	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	6,906	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	449	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	848	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	7,355	'	'	'
SEC Schedule III, Real Estate, Gross	8,203	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,023	'	'	'
Real Estate Investment Property, Net	7,180	'	'	'
Phoenixville Pike [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,204	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,880	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	13,418	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,204	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	24,298	'	'	'
SEC Schedule III, Real Estate, Gross	25,502	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-8,048	'	'	'
Real Estate Investment Property, Net	17,454	'	'	'
Piedmont Triad Research Wake 90 [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,160	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	41,632	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	48,231	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,160	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	89,862	'	'	'
SEC Schedule III, Real Estate, Gross	92,022	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-115	'	'	'
Real Estate Investment Property, Net	91,907	'	'	'
1701 / 1711 Research Blvd [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,492	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,834	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	14,315	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,492	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,149	'	'	'
SEC Schedule III, Real Estate, Gross	30,641	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-267	'	'	'
Real Estate Investment Property, Net	30,374	'	'	'
Road Tothe Cure [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,430	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	19,128	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	12,039	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,430	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	31,167	'	'	'
SEC Schedule III, Real Estate, Gross	35,597	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,017	'	'	'
Real Estate Investment Property, Net	29,580	'	'	'
San Diego Science Center [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,871	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	21,875	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	2,640	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,871	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	24,515	'	'	'
SEC Schedule III, Real Estate, Gross	28,386	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,073	'	'	'
Real Estate Investment Property, Net	22,313	'	'	'
Ten Thousand Two Hundred And Forty Science Center Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,079	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	12,124	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	22	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,079	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	12,146	'	'	'
SEC Schedule III, Real Estate, Gross	16,225	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,443	'	'	'
Real Estate Investment Property, Net	14,782	'	'	'
Science Center Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,630	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	16,029	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	21	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,630	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,050	'	'	'
SEC Schedule III, Real Estate, Gross	18,680	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,761	'	'	'
Real Estate Investment Property, Net	14,919	'	'	'
Shady Grove Road	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	143,067	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	28,895	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	197,548	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	3,339	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	28,895	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	200,887	'	'	'
SEC Schedule III, Real Estate, Gross	229,782	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-39,629	'	'	'
Real Estate Investment Property, Net	190,153	'	'	'
Sidney Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,579	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	50,459	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	170	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,579	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	50,629	'	'	'
SEC Schedule III, Real Estate, Gross	58,208	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-10,874	'	'	'
Real Estate Investment Property, Net	47,334	'	'	'
Sorrento Plaza [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,364	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,946	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	498	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,364	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	6,444	'	'	'
SEC Schedule III, Real Estate, Gross	8,808	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-945	'	'	'
Real Estate Investment Property, Net	7,863	'	'	'
One One Three Eight Eight Sorrento Valley Road [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,366	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,514	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	321	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,366	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,835	'	'	'
SEC Schedule III, Real Estate, Gross	11,201	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,133	'	'	'
Real Estate Investment Property, Net	10,068	'	'	'
Sorrento Valley Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,140	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,606	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	13,926	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,140	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,532	'	'	'
SEC Schedule III, Real Estate, Gross	20,672	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,606	'	'	'
Real Estate Investment Property, Net	18,066	'	'	'
ThreeEleven South Sarah [Member] [Domain]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	5,180	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,180	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	0	'	'	'
SEC Schedule III, Real Estate, Gross	5,180	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	5,180	'	'	'
Spring Mill Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,074	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	7,948	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	928	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,074	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,876	'	'	'
SEC Schedule III, Real Estate, Gross	9,950	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,149	'	'	'
Real Estate Investment Property, Net	7,801	'	'	'
Summers Ridge [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	47,301	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	47,301	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	0	'	'	'
SEC Schedule III, Real Estate, Gross	47,301	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	47,301	'	'	'
Trade Centre Avenue [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	3,275	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	15,404	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	3,275	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	15,404	'	'	'
SEC Schedule III, Real Estate, Gross	18,679	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,507	'	'	'
Real Estate Investment Property, Net	15,172	'	'	'
Torreyana Road [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,660	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	24,468	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	4,257	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,660	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	28,725	'	'	'
SEC Schedule III, Real Estate, Gross	36,385	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,579	'	'	'
Real Estate Investment Property, Net	31,806	'	'	'
Nine Thousand Eight Hundred And Sixty Five Towne Centre Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	5,738	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,991	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	20,206	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,738	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	23,197	'	'	'
SEC Schedule III, Real Estate, Gross	28,935	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,986	'	'	'
Real Estate Investment Property, Net	23,949	'	'	'
Nine Thousand Eight Hundred And Eighty Five Towne Centre Drive [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,982	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	28,513	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,982	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	28,513	'	'	'
SEC Schedule III, Real Estate, Gross	33,495	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,682	'	'	'
Real Estate Investment Property, Net	26,813	'	'	'
Tributary Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,060	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,597	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,060	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,597	'	'	'
SEC Schedule III, Real Estate, Gross	12,657	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,395	'	'	'
Real Estate Investment Property, Net	10,262	'	'	'
Nine Hundred Uniqema Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	404	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,692	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	69	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	404	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	3,761	'	'	'
SEC Schedule III, Real Estate, Gross	4,165	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-931	'	'	'
Real Estate Investment Property, Net	3,234	'	'	'
One Thousand Uniqema Boulevard [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,350	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	13,229	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	186	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,350	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	13,415	'	'	'
SEC Schedule III, Real Estate, Gross	14,765	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,229	'	'	'
Real Estate Investment Property, Net	11,536	'	'	'
Baltimore Garage, LLC [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	4,738	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	16,234	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	16,234	'	'	'
SEC Schedule III, Real Estate, Gross	16,234	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-347	'	'	'
Real Estate Investment Property, Net	15,887	'	'	'
University of Maryland BioPark I	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	79,698	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	19,783	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	13	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	19,796	'	'	'
SEC Schedule III, Real Estate, Gross	19,796	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-484	'	'	'
Real Estate Investment Property, Net	19,312	'	'	'
University of Maryland BioPark II	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	94,113	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	5,374	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	99,487	'	'	'
SEC Schedule III, Real Estate, Gross	99,487	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,246	'	'	'
Real Estate Investment Property, Net	97,241	'	'	'
University of Maryland BioPark III [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	6,061	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	8,481	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,061	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	8,481	'	'	'
SEC Schedule III, Real Estate, Gross	14,542	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	0	'	'	'
Real Estate Investment Property, Net	14,542	'	'	'
University of Maryland BioPark Garage	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	20,000	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	758	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	77,693	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	1,930	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	758	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	79,623	'	'	'
SEC Schedule III, Real Estate, Gross	80,381	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,807	'	'	'
Real Estate Investment Property, Net	78,574	'	'	'
University Tech Park at IIT [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	0	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	40,174	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	7,908	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	48,082	'	'	'
SEC Schedule III, Real Estate, Gross	48,082	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-680	'	'	'
Real Estate Investment Property, Net	47,402	'	'	'
Vassar Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,040	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	13,841	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	12,882	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,040	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	26,723	'	'	'
SEC Schedule III, Real Estate, Gross	28,763	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-6,860	'	'	'
Real Estate Investment Property, Net	21,903	'	'	'
Waples Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,470	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	2,907	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	11,464	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,470	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	14,371	'	'	'
SEC Schedule III, Real Estate, Gross	16,841	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-7,677	'	'	'
Real Estate Investment Property, Net	9,164	'	'	'
Wateridge Circle [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	6,536	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	34,462	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	4,082	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	6,536	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	38,544	'	'	'
SEC Schedule III, Real Estate, Gross	45,080	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-3,258	'	'	'
Real Estate Investment Property, Net	41,822	'	'	'
Wake Forest Biotech Place [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	1,266	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	87,812	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	93	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	1,266	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	87,910	'	'	'
SEC Schedule III, Real Estate, Gross	89,176	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,533	'	'	'
Real Estate Investment Property, Net	87,643	'	'	'
Walnut Street [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	5,200	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	36,067	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	5,200	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	36,067	'	'	'
SEC Schedule III, Real Estate, Gross	41,267	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-8,028	'	'	'
Real Estate Investment Property, Net	33,239	'	'	'
Weston Parkway [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	536	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	5,022	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	147	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	536	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	5,169	'	'	'
SEC Schedule III, Real Estate, Gross	5,705	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-539	'	'	'
Real Estate Investment Property, Net	5,166	'	'	'
Six Hundred And Seventy Five Only West Kendall Street Kendalla [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	4,922	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	121,182	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	2,258	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	4,922	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	123,440	'	'	'
SEC Schedule III, Real Estate, Gross	128,362	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-26,376	'	'	'
Real Estate Investment Property, Net	101,986	'	'	'
Fifty West Watkins Mill [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate, Gross	13,307	'	'	'
Real Estate Investment Property, Net	11,843	'	'	'
West Watkins Mill [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	2,320	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	10,393	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	198	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	2,320	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	10,591	'	'	'
SEC Schedule III, Real Estate, Gross	12,911	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-1,634	'	'	'
Real Estate Investment Property, Net	11,277	'	'	'
Woodside Technology Park	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	13,350	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	65,331	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	283	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	13,350	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	65,614	'	'	'
SEC Schedule III, Real Estate, Gross	78,964	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-2,920	'	'	'
Real Estate Investment Property, Net	76,044	'	'	'
Two Hundred And Seventeenth Place [Member]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Amount of Encumbrances	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Land	7,125	'	'	'
Real Estate And Accumulated Depreciation Initial Cost Of Ground Lease	0	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Initial Cost of Buildings and Improvements	3,529	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Costs Capitalized Subsequent to Acquisition, Carrying Costs	14,774	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Land	7,125	'	'	'
SEC Schedule III, Real Estate and Accumulated Depreciation, Carrying Amount of Buildings and Improvements	18,303	'	'	'
SEC Schedule III, Real Estate, Gross	25,428	'	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	-4,419	'	'	'
Real Estate Investment Property, Net	$21,009	'	'	'

Schedule_III_Schedule_III_Cons

Schedule III Schedule III Consolidated Financial Statement Schedule of Rental Properties and Accumulated Depreciation (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]	'	'	'	'
SEC Schedule III, Real Estate, Gross	$6,003,480	$4,923,166	$4,402,720	$3,878,092
SEC Schedule III, Real Estate Accumulated Depreciation, Real Estate Sold	1	1,530	'	'
SEC Schedule III, Real Estate Accumulated Depreciation, Depreciation Expense	-182,129	-152,506	-110,496	'
SEC Schedule III, Real Estate, Other Acquisitions	835,599	395,560	409,425	'
SEC Schedule III, Real Estate, Cost of Real Estate Sold	-4	-33,048	'	'
SEC Schedule III, Real Estate, Other Additions	244,719	157,934	115,203	'
Real Estate Investment Property, at Cost	6,003,480	4,923,166	'	'
Real Estate Investment Property, Accumulated Depreciation	785,578	603,450	'	'
SEC Schedule III, Real Estate Accumulated Depreciation	($785,578)	($603,450)	($452,474)	($341,978)