Equity Commonwealth (EQC) 10-Q 6 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Jul. 31, 2015
Document and Entity Information
Entity Registrant Name	Equity Commonwealth
Entity Central Index Key	803,649
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		129,760,214
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Real estate properties:
Land	$ 456,614	$ 714,238
Buildings and improvements	3,834,855	5,014,205
Total real estate properties, at cost, gross	4,291,469	5,728,443
Accumulated depreciation	(913,303)	(1,030,445)
Total real estate properties, at cost, net	3,378,166	4,697,998
Properties held for sale	360,781	0
Acquired real estate leases, net	121,912	198,287
Cash and cash equivalents	1,286,902	364,516
Restricted cash	31,351	32,257
Rents receivable, net of allowance for doubtful accounts of $10,008 and $6,565, respectively	209,089	248,101
Other assets, net	159,845	220,480
Total assets	5,548,046	5,761,639
LIABILITIES AND SHAREHOLDERS’ EQUITY
Senior unsecured debt, net	1,460,131	1,598,416
Mortgage notes payable, net	513,561	609,249
Liabilities related to properties held for sale	20,336	0
Accounts payable and accrued expenses	128,590	162,204
Assumed real estate lease obligations, net	5,728	26,784
Rent collected in advance	21,860	31,359
Security deposits	10,610	14,044
Total liabilities	2,160,816	2,442,056
Common shares of beneficial interest, $0.01 par value:
Common shares of beneficial interest, $0.01 par value: 350,000,000 shares authorized; 129,760,214 and 129,607,279 shares issued and outstanding, respectively	1,298	1,296
Additional paid in capital	4,495,244	4,487,133
Cumulative net income	2,260,098	2,233,852
Cumulative other comprehensive loss	(5,963)	(53,216)
Cumulative common distributions	(3,111,868)	(3,111,868)
Cumulative preferred distributions	(636,233)	(622,271)
Total shareholders’ equity	3,387,230	3,319,583
Total liabilities and shareholders’ equity	5,548,046	5,761,639
Series D
Preferred shares of beneficial interest, $0.01 par value: 50,000,000 shares authorized;
Series D preferred shares; 6 1/2% cumulative convertible; 4,915,196 and 4,915,497 shares issued and outstanding, respectively, aggregate liquidation preference of $122,880 and $122,887, respectively	119,263	119,266
Series E
Preferred shares of beneficial interest, $0.01 par value: 50,000,000 shares authorized;
Series E preferred shares; 7 1/4% cumulative redeemable on or after May 15, 2016; 11,000,000 shares issued and outstanding, aggregate liquidation preference $275,000	$ 265,391	$ 265,391

CONDENSED CONSOLIDATED BALANCE3

CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) Parenthetical) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Rents receivable, allowance for doubtful accounts	$ 10,008	$ 6,565
Common shares of beneficial interest, par value (in dollars per share)	$ 0.01	$ 0.01
Common shares of beneficial interest, shares authorized (in shares)	350,000,000	350,000,000
Common shares of beneficial interest, shares issued (in shares)	129,760,214	129,607,279
Common shares of beneficial interest, shares outstanding (in shares)	129,760,214	129,607,279
Series D
Preferred shares of beneficial interest, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred shares of beneficial interest, shares authorized (in shares)	50,000,000	50,000,000
Preferred shares, dividend yield	6.50%	6.50%
Preferred shares of beneficial interest, shares issued (in shares)	4,915,196	4,915,497
Preferred shares, of beneficial interest, shares outstanding (in shares)	4,915,196	4,915,497
Preferred shares, aggregate liquidation preference	$ 122,880	$ 122,887
Series E
Preferred shares of beneficial interest, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred shares of beneficial interest, shares authorized (in shares)	50,000,000	50,000,000
Preferred shares, dividend yield	7.25%	7.25%
Preferred shares of beneficial interest, shares issued (in shares)	11,000,000	11,000,000
Preferred shares, of beneficial interest, shares outstanding (in shares)	11,000,000	11,000,000
Preferred shares, aggregate liquidation preference	$ 275,000	$ 275,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Revenues:
Rental income	$ 163,697	$ 172,407	$ 331,669	$ 344,447
Tenant reimbursements and other income	39,997	42,787	85,080	88,007
Total revenues	203,694	215,194	416,749	432,454
Expenses:
Operating expenses	89,686	92,701	187,557	194,432
Depreciation and amortization	53,637	59,831	116,336	111,480
General and administrative	10,911	24,097	27,469	48,945
Loss on asset impairment	15,258	22,683	17,162	17,922
Acquisition related costs	0	0	0	5
Total expenses	169,492	199,312	348,524	372,784
Operating income	34,202	15,882	68,225	59,670
Interest and other income	728	281	4,176	665
Interest expense (including net amortization of debt discounts, premiums and deferred financing fees of $(177), $(300), $(148) and $(609), respectively)	(27,973)	(37,899)	(57,815)	(75,834)
Gain on early extinguishment of debt	10,426	0	9,998	0
Loss on sale of equity investment	0	(33)	0	(33)
Gain on issuance of shares by an equity investee	0	16,911	0	17,020
Foreign currency exchange gain	856	0	856	0
(Loss) gain on sale of properties	(2,708)	0	3,160	0
Income (loss) from continuing operations before income taxes and equity in earnings of investees	15,531	(4,858)	28,600	1,488
Income tax expense	(2,915)	(908)	(2,354)	(1,463)
Equity in earnings of investees	0	12,454	0	23,388
Income from continuing operations	12,616	6,688	26,246	23,413
Discontinued operations:
Income from discontinued operations	0	4,114	0	8,125
Loss on asset impairment from discontinued operations	0	(2,072)	0	(2,360)
Loss on early extinguishment of debt from discontinued operations	0	(3,345)	0	(3,345)
Net income	12,616	5,385	26,246	25,833
Preferred distributions	(6,981)	(6,982)	(13,962)	(18,133)
Excess fair value of consideration over carrying value of preferred shares	0	(16,205)	0	(16,205)
Net income (loss) attributable to Equity Commonwealth common shareholders	5,635	(17,802)	12,284	(8,505)
Amounts attributable to Equity Commonwealth common shareholders:
Income (loss) from continuing operations	5,635	(16,499)	12,284	(10,925)
Income from discontinued operations	0	4,114	0	8,125
Loss on asset impairment from discontinued operations	0	(2,072)	0	(2,360)
Loss on early extinguishment of debt from discontinued operations	0	(3,345)	0	(3,345)
Net income (loss) attributable to Equity Commonwealth common shareholders	$ 5,635	$ (17,802)	$ 12,284	$ (8,505)
Weighted average common shares outstanding — basic (in shares)	129,733	123,812	129,714	121,121
Weighted average common shares outstanding — diluted (in shares)	130,537	123,812	130,205	121,121
Basic and diluted earnings per common share attributable to Equity Commonwealth common shareholders:
Income (loss) from continuing operations (in dollars per share)	$ 0.04	$ (0.13)	$ 0.09	$ (0.09)
(Loss) income from discontinued operations (in dollars per share)	0	(0.01)	0	0.02
Net income (loss) (in dollars per share)	0.04	(0.14)	0.09	(0.07)
Distributions declared per common share (in dollars per share)	$ 0	$ 0	$ 0	$ 0.25

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statement [Abstract]
Amortization of debt discounts, premiums and deferred financing fees	$ (177)	$ (300)	$ (148)	$ (609)

CONDENSED CONSOLIDATED STATEME6

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 12,616	$ 5,385	$ 26,246	$ 25,833
Other comprehensive income, net of tax:
Unrealized gain (loss) on derivative instruments and other assets	958	627	(1,664)	1,627
Foreign currency translation adjustments	65,307	4,961	48,917	15,548
Equity in unrealized loss of an investee	0	(69)	0	(49)
Total comprehensive income	$ 78,881	$ 10,904	$ 73,499	$ 42,959

CONDENSED CONSOLIDATED STATEME7

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 26,246	$ 25,833
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation	86,374	80,512
Net amortization of debt discounts, premiums and deferred financing fees	(148)	(612)
Straight line rental income	(1,611)	(7,201)
Amortization of acquired real estate leases	20,413	27,806
Other amortization	12,782	9,579
Share-based compensation	8,110	3,354
Loss on asset impairment	17,162	20,282
(Gain) loss on early extinguishment of debt	(9,998)	3,345
Equity in earnings of investees	0	(23,388)
Loss on sale of equity investments	0	33
Gain on issuance of shares by an equity investee	0	(17,020)
Distributions of earnings from investees	0	20,680
Net gain on sale of properties	(3,160)	0
Other non-cash expenses	0	15,048
Change in assets and liabilities:
Restricted cash	(2,917)	641
Rents receivable and other assets	(20,462)	(19,856)
Accounts payable and accrued expenses	(847)	(7,833)
Rent collected in advance	(8,539)	(2,339)
Security deposits	597	241
Due to related persons	0	47
Cash provided by operating activities	124,002	129,152
CASH FLOWS FROM INVESTING ACTIVITIES:
Real estate improvements	(28,623)	(60,437)
Principal payments received from direct financing lease	3,789	3,612
Proceeds from sale of properties, net	962,003	185,179
Proceeds from sale of securities	27,068	0
Proceeds from sale of equity investments, net	0	5,776
Increase in restricted cash	(2,313)	(3,661)
Cash provided by investing activities	961,924	130,469
CASH FLOWS FROM FINANCING ACTIVITIES:
Payments on borrowings	(141,908)	(15,998)
Deferred financing fees	(7,143)	0
Distributions to common shareholders	0	(29,597)
Distributions to preferred shareholders	(13,962)	(11,151)
Cash used in financing activities	(163,013)	(56,746)
Effect of exchange rate changes on cash	(527)	757
Increase in cash and cash equivalents	922,386	203,632
Cash and cash equivalents at beginning of period	364,516	217,032
Cash and cash equivalents at end of period	1,286,902	420,664
SUPPLEMENTAL CASH FLOW INFORMATION:
Interest paid	62,094	77,120
Taxes paid	3,088	2,732
NON-CASH INVESTING ACTIVITIES:
Increase in capital expenditures recorded as liabilities	$ 523	$ 13,368

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements of EQC have been prepared without audit. Certain information and footnote disclosures required by U.S. generally accepted accounting principles, or GAAP, for complete financial statements have been condensed or omitted. We believe the disclosures made are adequate to make the information presented not misleading. However, the accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes contained in our Annual Report on Form 10-K (Annual Report) for the year ended December 31, 2014. Capitalized terms used, but not defined in this Quarterly Report, have the same meanings as in our Annual Report. In the opinion of our management, all adjustments, which include only normal recurring adjustments considered necessary for a fair presentation, have been included. All intercompany transactions and balances with or among our subsidiaries have been eliminated. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. Reclassifications have been made to the prior years’ financial statements to conform to the current year’s presentation. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect reported amounts. Actual results could differ from those estimates. Significant estimates in the condensed consolidated financial statements include the allowance for doubtful accounts, purchase price allocations, useful lives of fixed assets and impairment of real estate and intangible assets. Share amounts are presented in whole numbers, except where noted.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2015
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements In April 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, or ASU 2014-08. ASU 2014-08 changes the criteria for reporting a discontinued operation. Under the new pronouncement, a disposal of a part of an organization that has a major effect on its operations and financial results is a discontinued operation. We adopted ASU 2014-08 on January 1, 2015, and determined that our individual 2015 dispositions and properties held for sale as of June 30, 2015 do not represent a strategic shift, as defined by the standard, that has or will have a major effect on our operations and financial results. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which provides guidance for revenue recognition. This update is effective for interim and annual reporting periods beginning after December 15, 2017. We are currently in the process of evaluating the impact, if any, the adoption of this ASU will have on our condensed consolidated financial statements. In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. This standard amends existing guidance to require the presentation of debt issuance costs in the balance sheet as a deduction from the carrying amount of the related debt liability instead of as a deferred charge. It is effective for annual reporting periods beginning after December 15, 2015, but early adoption is permitted. We do not expect that the adoption of this standard will have a material impact on our condensed consolidated financial statements.

Board of Trustees

Board of Trustees	6 Months Ended
	Jun. 30, 2015
Board of Trustees
Board of Trustees	Board of Trustees On March 18, 2014, Related Fund Management, LLC (Related) and Corvex Management LP (Corvex) together, (Related/Corvex), delivered written consents which they represented were from a sufficient number of holders of our outstanding common shares to remove all of our then Trustees (former Trustees) and any other person or persons elected or appointed to our Board of Trustees prior to the effective time of the Related/Corvex removal proposal. After inspection, our then Board of Trustees determined that holders of more than two-thirds of our outstanding common shares as of the February 18, 2014 record date consented to the Related/Corvex proposal, reaching the threshold required to remove all of our then Trustees and any other person or persons appointed as a Trustee prior to the effective time of the Related/Corvex removal proposal. Accordingly, on March 25, 2014, all of our former Trustees certified their removal as Trustees of EQC. On May 23, 2014, at a special meeting of our shareholders (Special Meeting), the following seven individuals were elected to serve on our Board of Trustees: Sam Zell, who serves as the Chairman of the new Board of Trustees, James S. Corl, Edward A. Glickman, David A. Helfand, Peter Linneman, James L. Lozier, Jr. and Kenneth Shea. Each of the foregoing individuals was nominated to serve on the new Board of Trustees by Related/Corvex. On July 31, 2014, our shareholders re-elected the seven individuals listed above and elected Martin L. Edelman, Mary Jane Robertson, Gerald A. Spector and James A. Star to serve on our Board of Trustees, bringing our total number of Trustees to eleven (new Board of Trustees). At the 2015 annual meeting of shareholders held on June 16, 2015, our shareholders re-elected each of our eleven Trustees to serve on our Board of Trustees for the 2015-2016 term.

Real Estate Properties

Real Estate Properties	6 Months Ended
	Jun. 30, 2015
Real Estate [Abstract]
Real Estate Properties	Real Estate Properties During the six months ended June 30, 2015 and 2014 , we made improvements to our properties totaling $27.8 million and $ 47.0 million , respectively. Properties Held For Sale: We classify all properties that meet the criteria outlined in the Property, Plant and Equipment Topic of the FASB Accounting Standards Codification (Codification) as held for sale on our condensed consolidated balance sheets. As of June 30, 2015 , we classified Illinois Center and 16th and Race Street (together, two properties and three buildings), with a combined 2,698,787 square feet, as held for sale. On August 4, 2015 we sold Illinois Center (see Note 18). The sale of 16th and Race Street is projected to close in the third quarter of 2015, subject to customary closing conditions. There is no certainty that these conditions will be met or that this transaction will close. As of December 31, 2014, we had no properties classified as held for sale. Summarized balance sheet information for all properties classified as held for sale is as follows (in thousands): June 30, 2015 Real estate properties $ 341,263 Acquired real estate leases 13,238 Other assets, net 6,280 Properties held for sale $ 360,781 Accounts payable and accrued expenses $ 12,387 Assumed real estate lease obligations 6,516 Rent collected in advance 113 Security deposits 1,320 Liabilities related to properties held for sale $ 20,336 During March 2014, the former management team ceased to actively market two CBD properties ( two buildings) and 29 suburban properties ( 65 buildings) with a combined 5,641,450 square feet that we had previously classified as held for sale as of December 31, 2013. These properties were not under agreement for sale when our former Trustees were removed in March 2014. These properties were reclassified to properties held and used in operations because they no longer met the requirements under GAAP for classification as held for sale. Operating results for these properties were reclassified from discontinued operations to continuing operations for all periods presented herein. In connection with this reclassification, we reversed previously recorded impairment losses totaling $4.8 million , which included the elimination of estimated costs to sell. Property Dispositions: During the six months ended June 30, 2015 , we disposed of the following properties (dollars in thousands): Asset Date Disposed Segment Number of Number of Square Footage Gross Sales Price Gain (Loss) on Sale Properties 11350 North Meridian Street January 2015 Suburban 1 1 72,264 $ 4,200 $ 766 333 Laurel Oak Drive (1) March 2015 Suburban — 1 27,164 2,450 251 1921 E. Alton Avenue March 2015 Suburban 1 1 67,846 14,533 4,851 46 Inverness Center Parkway April 2015 Suburban — — — 2,000 1,857 225 Water Street (2) May 2015 CBD 1 1 318,997 — — Sorrento Valley Business Park June 2015 Suburban 1 4 105,003 23,500 11,896 Portfolio of properties 7450 Campus Drive May 2015 Suburban 1 1 77,411 129 Worthington Ridge Road May 2015 Suburban 1 1 227,500 599 Research Parkway May 2015 Suburban 1 1 48,249 181 Marsh Hill Road May 2015 Suburban 1 1 162,036 101 Barnes Road May 2015 Suburban 1 1 45,755 15 Sterling Drive May 2015 Suburban 1 1 173,015 35 Thorpe Avenue May 2015 Suburban 1 1 79,862 50 Barnes Industrial Road North May 2015 Suburban 1 1 154,255 5-9 Barnes Industrial Road May 2015 Suburban 1 1 38,006 860 North Main Street May 2015 Suburban 1 1 31,165 One Barnes Industrial Road South May 2015 Suburban 1 1 30,170 Village Lane May 2015 Suburban 1 2 58,185 100 Northfield Drive May 2015 Suburban 1 1 116,986 905 Meridian Lake Drive May 2015 Suburban 1 1 74,652 1717 Deerfield Road May 2015 Suburban 1 1 141,186 1955 West Field Court May 2015 Suburban 1 1 59,130 5015 S. Water Circle May 2015 Suburban 1 1 113,524 Adams Place May 2015 Suburban 1 2 230,259 Cabot Business Park May 2015 Suburban 1 2 252,755 2300 Crown Colony Drive May 2015 Suburban 1 1 45,974 Myles Standish Industrial Park May 2015 Suburban 1 2 74,800 340 Thompson Road May 2015 Suburban 1 1 25,000 100 South Charles Street May 2015 CBD 1 1 159,616 6710 Oxon Hill May 2015 Suburban 1 1 118,336 8800 Queen Avenue South May 2015 Suburban 1 1 280,822 9800 Sherlard Parkway May 2015 Suburban 1 1 46,765 Rosedale Corporate Plaza May 2015 Suburban 1 3 149,116 1000 Shelard Parkway May 2015 Suburban 1 1 62,499 525 Park Street May 2015 CBD 1 1 75,636 1900 Meyer Drury Drive May 2015 Suburban 1 1 65,225 131-165 West Ninth Street May 2015 Suburban 1 1 75,517 7-9 Vreeland Road May 2015 Suburban 1 1 155,891 5 Paragon Drive May 2015 Suburban 1 1 119,089 Asset Date Disposed Segment Number of Number of Square Footage Gross Sales Price Gain (Loss) on Sale 1000 Vorhees Drive and 400 Laurel Oak Drive(1) May 2015 Suburban 1 2 125,415 1601 Veterans Highway May 2015 Suburban 1 1 63,608 Two Corporate Center Drive May 2015 Suburban 1 1 291,230 11311 Cornell Park Drive May 2015 Suburban 1 1 93,413 5300 Kings Island Drive May 2015 Suburban 1 1 159,421 3 Crown Point Court May 2015 Suburban 1 1 73,987 515 Pennsylvania Avenue May 2015 Suburban 1 1 82,000 443 Gulph Road May 2015 Suburban 1 1 21,000 4350 Northern Pike May 2015 Suburban 1 1 503,885 Thunderbolt Place May 2015 Suburban 1 2 100,505 6160 Kempsville Circle May 2015 Suburban 1 1 129,565 448 Viking Drive May 2015 Suburban 1 1 75,374 Portfolio of small office and industrial assets 45 53 5,287,790 $ 376,000 $ (7,915 ) 2501 20th Place South June 2015 CBD 1 1 125,722 420 20th Street North June 2015 CBD 1 1 514,893 Inverness Center June 2015 Suburban 1 4 475,951 701 Poydras Street June 2015 CBD 1 1 1,256,971 300 North Greene Street June 2015 CBD 1 1 324,305 1320 Main Street June 2015 CBD 1 1 334,075 AL, LA, NC, SC office portfolio 6 9 3,031,917 $ 417,450 $ 41,596 12655 Olive Boulevard June 2015 Suburban 1 1 98,588 1285 Fern Ridge Parkway June 2015 Suburban 1 1 66,510 St. Louis portfolio 2 2 165,098 $ 14,300 $ (2,338 ) 310-314 Invermay Road (3) April 2015 Suburban 1 1 47,480 253-293 George Town Road (3) April 2015 Suburban 1 1 143,914 7 Modal Crescent June 2015 Suburban 1 1 164,160 71-93 Whiteside Road June 2015 Suburban 1 1 303,488 9-13 Titanium Court June 2015 Suburban 1 1 69,664 16 Rodborough Road June 2015 Suburban 1 1 90,525 22 Rodborough Road June 2015 Suburban 1 1 43,427 127-161 Cherry Lane June 2015 Suburban 1 1 278,570 310-320 Pitt Street June 2015 CBD 1 1 313,865 44-46 Mandarin Street June 2015 Suburban 1 1 226,718 19 Leadership Way June 2015 Suburban 1 1 76,714 Australia portfolio (4) 11 11 1,758,525 $ 232,955 $ (47,804 ) 68 83 10,834,604 $ 1,087,388 $ 3,160 (1) This property contains three buildings. We sold one building in March 2015 and two buildings in May 2015. (2) Title to this property was transferred to the lender pursuant to a consensual foreclosure in full satisfaction of the mortgage debt with a principal balance of $40.1 million , resulting in a gain on early extinguishment of debt of $17.3 million for the three and six months ended June 30, 2015. See Note 8 for additional information. (3) These properties were sold in a separate transaction to a different buyer than other Australian properties. (4) The loss on sale includes a $63.2 million cumulative foreign currency translation adjustment reclassified from cumuluative other comprehensive loss due to the disposition of the Australian portfolio. On June 27, 2014, we sold one CBD property ( two buildings) and 13 suburban properties ( 41 buildings) with a combined 2,784,098 square feet for an aggregate sales price of $215.9 million , excluding mortgage debt repayments and closing costs. In conjunction with this transaction, we recognized a loss on asset impairment of $2.4 million and a loss on early extinguishment of debt of $3.3 million . Results of operations for properties sold prior to December 31, 2014 are included in discontinued operations in our condensed consolidated statements of operations. Summarized income statement information for properties included in discontinued operations is as follows (in thousands): Three Months Ended Six Months Ended June 30, 2014 Rental income $ 6,962 $ 14,236 Tenant reimbursements and other income 801 1,323 Total revenues 7,763 15,559 Operating expenses 3,375 6,854 General and administrative — 3 Total expenses 3,375 6,857 Operating income 4,388 8,702 Interest expense (274 ) (577 ) Income from discontinued operations $ 4,114 $ 8,125

Investment in Direct Financing

Investment in Direct Financing Lease	6 Months Ended
	Jun. 30, 2015
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Investment in Direct Financing Lease	Investment in Direct Financing Lease We have an investment in a direct financing lease that relates to a lease with a term that exceeds 75% of the useful life of an office tower located within a mixed use property in Phoenix, AZ. We recognize income using the effective interest method to produce a level yield on funds not yet recovered. The carrying amount of our net investment of $8.7 million and $12.5 million as of June 30, 2015 and December 31, 2014, respectively, is included in other assets in our condensed consolidated balance sheets. We monitor the payment history and credit profile of the tenant and have determined that no allowance for losses related to our direct financing lease was necessary at June 30, 2015 and December 31, 2014 . Our direct financing lease has an expiration date in 2045.

Equity Investments

Equity Investments	6 Months Ended
	Jun. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
Equity Investments	Equity Investments Investment in SIR SIR is a REIT that is primarily focused on owning and investing in net leased, single tenant properties. SIR was an unconsolidated equity method investment from July 2, 2013 until July 9, 2014 . On July 9, 2014 , we sold our entire stake of 22,000,000 common shares of SIR. As a result of this sale, we no longer hold any interest in SIR. For the three and six months ended June 30, 2014 , we recorded equity in earnings of $12.4 million and $23.4 million , respectively, related to our investment in SIR on our condensed consolidated statement of operations. During the three and six months ended June 30, 2014 , we received cash distributions from SIR totaling $10.6 million and $20.7 million , respectively. The following unaudited summarized income statement information of SIR as reported in SIR's Quarterly Report on Form 10-Q for the three and six months ended June 30, 2014 is as follows (in thousands, except per share data): Three Months Ended Six Months Ended June 30, 2014 Rental income $ 48,465 93,528 Tenant reimbursements and other income 8,092 16,057 Total revenues 56,557 109,585 Operating expenses 9,985 19,964 Depreciation and amortization 10,495 19,789 Acquisition related costs 136 374 General and administrative 2,198 7,374 Total expenses 22,814 47,501 Operating income 33,743 62,084 Interest expense (3,634 ) (6,992 ) Gain on early extinguishment of debt — 243 Income before income tax expense and equity in earnings of an investee 30,109 55,335 Income tax expense (19 ) (90 ) Equity in earnings of an investee 118 21 Net income $ 30,208 $ 55,266 Weighted average common shares outstanding 54,178 52,021 Net income per common share $ 0.56 $ 1.06 Investment in AIC As of May 9, 2014, we had a net investment of $5.8 million in AIC, an insurance company that was owned in equal proportion by us, our former manager Reit Management & Research LLC (RMR), SIR and five other companies to which RMR provides management services. On May 9, 2014, as a result of the removal of the former Trustees and in accordance with the terms of the shareholder agreement between us and the other AIC shareholders, the other AIC shareholders exercised their right to purchase all of the 20,000 shares of AIC we then owned. We received $5.8 million in aggregate proceeds from this sale. We no longer own any interest in AIC. For the period from April 1, 2014 through May 9, 2014 and for the period from January 1, 2014 through May 9, 2014, we recorded equity in earnings (loss) of $0.04 million and $(0.1) million , respectively, related to our investment in AIC on our condensed consolidated statement of operations. Our participation in the AIC property insurance program expired in June 2014. See Note 17 for additional information about our investment in AIC.

Real Estate Mortgages Receivabl

Real Estate Mortgages Receivable	6 Months Ended
	Jun. 30, 2015
Real Estate Mortgages Receivable
Real Estate Mortgages Receivable	Real Estate Mortgages Receivable As of June 30, 2015 and December 31, 2014 , we had total real estate mortgages receivable with an aggregate carrying value of $8.1 million included in other assets in our condensed consolidated balance sheets. We provided mortgage financing totaling $7.7 million at 6.0% per annum in connection with our sale of three suburban office and industrial properties ( 18 buildings) in January 2013 in Dearborn, MI; this real estate mortgage requires monthly interest payments and matures on January 24, 2023 . We also provided mortgage financing totaling $0.4 million at 6.0% per annum in connection with our sale of a suburban office property in Salina, NY in April 2012. This real estate mortgage requires monthly interest payments and matures on April 30, 2019 . We monitor the payment history of the borrowers and have determined that no allowance for losses related to these real estate mortgages receivable were necessary at June 30, 2015 and December 31, 2014 .

Indebtedness

Indebtedness	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Indebtedness	Indebtedness Unsecured Revolving Credit Facility and Term Loan: Prior to January 29, 2015, we had a $750.0 million unsecured revolving credit facility. The unsecured revolving credit facility was set to mature on October 19, 2015, and had an interest rate of LIBOR plus a spread, which was 150 basis points as of December 31, 2014. We paid a facility fee of 35 basis points per annum on the total amount of lending commitments under our revolving credit facility. Prior to January 29, 2015, we also had a $400.0 million unsecured term loan that was set to mature on December 15, 2016. Our term loan had an interest rate of LIBOR plus a spread, which was 185 basis points as of December 31, 2014. On January 29, 2015, we entered into a new credit agreement, pursuant to which the lenders agreed to provide (i) a $750.0 million unsecured revolving credit facility, (ii) a $200.0 million 5 -year term loan facility and (iii) a $200.0 million 7 -year term loan facility. The new agreement replaced our prior credit agreement, dated as of August 9, 2010, and our prior term loan agreement, dated as of December 16, 2010. In connection with the new agreement, we recognized a loss on early extinguishment of debt of $0.4 million from the write-off of unamortized deferred financing fees for the six months ended June 30, 2015 . The revolving credit facility has a scheduled maturity date of January 28, 2019, which maturity date may be extended for up to two additional periods of six months at our option subject to satisfaction of certain conditions and the payment of an extension fee of 0.075% of the aggregate amount available under the revolving credit facility. The 5-year term loan and the 7-year term loan have scheduled maturity dates of January 28, 2020 and January 28, 2022, respectively. We used the proceeds of borrowings under the credit agreement to repay all amounts outstanding and due under the previous term loan agreement. The credit agreement permits us to utilize up to $100.0 million of the revolving credit facility for the issuance of letters of credit. Amounts outstanding under the credit agreement generally may be prepaid at any time without premium or penalty, subject to certain exceptions. We have the right to request increases in the aggregate maximum amount of borrowings available under the revolving credit facility and term loans up to an additional $1.15 billion , subject to certain conditions. Borrowings under the 5-year term loan and 7-year term loan will, subject to certain exceptions, bear interest at a LIBOR rate plus a margin of 90 to 180 basis points for the 5-year term loan and 140 to 235 basis points for the 7-year term loan, in each case depending on our credit rating. Borrowings under the revolving credit facility will, subject to certain exceptions, bear interest at a rate equal to, at our option, either a LIBOR rate or a base rate plus a margin of 87.5 to 155 basis points for LIBOR rate advances and 0 to 55 basis points for base rate advances, in each case depending on our credit rating. In addition, we are required to pay a facility fee of 12.5 to 30 basis points, depending on our credit rating, on the borrowings available under the revolving credit facility, whether or not utilized. Borrowings under our revolving credit facility currently bear interest at LIBOR plus a spread, which was 125 basis points as of June 30, 2015 . As of June 30, 2015 , the interest rate payable on borrowings under our revolving credit facility was 1.44% . As of June 30, 2015 , we had no balance outstanding and $750.0 million available under our revolving credit facility. Our term loans currently bear interest at a rate of LIBOR plus a spread, which was 140 and 180 basis points for the 5-year and 7-year term loan, respectively, as of June 30, 2015 . As of June 30, 2015 , the interest rates for the amounts outstanding under our 5-year term loan and 7-year term loan were 1.59% and 1.99% , respectively. As of June 30, 2015 , we had $200.0 million outstanding under each of our 5-year and 7-year term loans. Debt Covenants: Our public debt indenture and related supplements, our revolving credit facility agreement and our term loan agreement contain a number of financial and other covenants, including covenants that restrict our ability to incur indebtedness or to make distributions under certain circumstances and require us to maintain financial ratios and a minimum net worth. At June 30, 2015 , we believe we were in compliance with all of our respective covenants under our public debt indenture and related supplements, our revolving credit facility and our term loan agreements. Senior Unsecured Notes: On May 1, 2015, we redeemed at par $138.8 million of our 5.75% senior unsecured notes due 2015 and recognized a loss on early extinguishment of debt of $0.1 million from the write-off of an unamortized discount and unamortized deferred financing fees. Mortgage Notes Payable: At June 30, 2015 , seven of our properties ( 11 buildings) with an aggregate net book value of $605.5 million had secured mortgage notes totaling $513.6 million (including net premiums and discounts) maturing from 2016 through 2026. During the quarter ended June 30, 2014, we made the decision to cease making loan servicing payments on 225 Water Street in Jacksonville, Florida. The first payment we determined not to make for this property was due on June 11, 2014. The property was secured by a non-recourse mortgage loan. On October 10, 2014, we were notified by the lender that our decision to cease making loan servicing payments created an event of default effective July 11, 2014, and the lender exercised its option to accelerate the maturity of the unpaid balance of the loan. Beginning July 11, 2014, we accrued interest on this loan at 10.03% , to include the 4.0% of default interest. The lender filed a suit of foreclosure for this property and we cooperated with the lender to allow for a consensual foreclosure process. On May 22, 2015, title to 225 Water Street was transferred to the lender pursuant to the consensual foreclosure in full satisfaction of the mortgage debt, with a principal balance of $40.1 million . The transaction resulted in a gain on early extinguishment of debt of $17.3 million for the excess of the debt principal balance over the net book value of the property for the three and six months ended June 30, 2015. In accordance with the agreement to sell 1320 Main Street, we were required to deliver the property unencumbered. On June 3, 2015, prior to the sale, we defeased the $38.7 million outstanding balance of the mortgage loan secured by 1320 Main Street. This debt is no longer reflected in the accompanying condensed consolidated balance sheet as of June 30, 2015. The defeasance costs and write off of the unamortized deferred financing costs, net of the write off of the unamortized premium, resulted in a net loss on early extinguishment of debt of $6.2 million for the three and six months ended June 30, 2015. In accordance with the agreement to sell 2501 20th Place South, we were required to deliver the property unencumbered. On June 5, 2015, we prepaid $10.0 million of 7.36% mortgage debt at 2501 20th Place South and recognized a loss on early extinguishment of debt totaling $0.6 million for the three and six months ended June 30, 2015, which consisted of a prepayment premium and the write off of unamortized deferred financing fees, net of the write off of an unamortized premium.

Shareholders' Equity

Shareholders' Equity	6 Months Ended
	Jun. 30, 2015
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity Common Share Issuances: During the six months ended June 30, 2015 , we issued 144 common shares to holders of 301 of our series D cumulative convertible preferred shares (series D preferred shares) who elected to convert their series D preferred shares into our common shares. During 2014, we issued 10,412,499 common shares to holders of 10,264,503 of our series D preferred shares who converted their series D preferred shares into our common shares. See Note 13 for information regarding equity issuances related to share-based compensation. Preferred Share Distributions: In 2015, our Board of Trustees declared distributions on our series D preferred shares and series E cumulative redeemable preferred shares to date as follows: Declaration Date Record Date Payment Date Series D Dividend Per Share Series E Dividend Per Share January 16, 2015 February 2, 2015 February 17, 2015 $ 0.40625 $ 0.453125 April 8, 2015 May 1, 2015 May 15, 2015 $ 0.40625 $ 0.453125 July 9, 2015 July 31, 2015 August 17, 2015 $ 0.40625 $ 0.453125 Series D Preferred Shares: The removal of our former Trustees on March 25, 2014, triggered a Fundamental Change Conversion Right of the series D preferred shares, as defined in our Articles Supplementary dated October 10, 2006, setting forth the terms of the series D preferred shares. Pursuant to such right, the holders of series D preferred shares had the option to elect to convert all or any portion of their series D preferred shares at any time from April 9, 2014 until the close of business on May 14, 2014 into a number of common shares per $25.00 liquidation preference of the series D preferred shares equal to the sum of such $25.00 liquidation preference plus accrued and unpaid dividends to, but not including, May 14, 2014, divided by 98% of the average of the closing sale prices of the common shares for the five consecutive trading days ending on May 9, 2014, or the Fundamental Change Conversion Rate. Holders of 10,263,003 series D preferred shares elected to exercise their Fundamental Change Conversion Right and converted their series D preferred shares into 10,411,779 of our common shares. As a result of this transaction, we recorded a distribution of $16.2 million , for the excess of the market value of the common shares issued above the carrying value of the series D preferred shares redeemed. As of June 30, 2015 , we had 4,915,196 outstanding series D preferred shares that were convertible into 2,363,103 of our common shares.

Cumulative Other Comprehensive

Cumulative Other Comprehensive Loss	6 Months Ended
	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Cumulative Other Comprehensive Loss	Cumulative Other Comprehensive Loss The following tables present the amounts recognized in cumulative other comprehensive loss by component for the three and six months ended June 30, 2015 (in thousands): Three Months Ended June 30, 2015 Unrealized Loss on Derivative Instruments and Other Assets Foreign Currency Translation Adjustments Total Balances as of March 31, 2015 $ (6,921 ) $ (65,307 ) $ (72,228 ) Other comprehensive (loss) income before reclassifications (274 ) 2,100 1,826 Amounts reclassified from cumulative other comprehensive loss to net income 1,232 63,207 64,439 Net current period other comprehensive income 958 65,307 66,265 Balances as of June 30, 2015 $ (5,963 ) $ — $ (5,963 ) Six Months Ended June 30, 2015 Unrealized Loss on Derivative Instruments and Other Assets Foreign Currency Translation Adjustments Total Balances as of December 31, 2014 $ (4,299 ) $ (48,917 ) $ (53,216 ) Other comprehensive loss before reclassifications (1,043 ) (14,290 ) (15,333 ) Amounts reclassified from cumulative other comprehensive loss to net income (621 ) 63,207 62,586 Net current period other comprehensive (loss) income (1,664 ) 48,917 47,253 Balances as of June 30, 2015 $ (5,963 ) $ — $ (5,963 ) The following tables present reclassifications out of cumulative other comprehensive loss for the three and six months ended June 30, 2015 (in thousands): Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income Details about Cumulative Other Comprehensive Loss Components Three Months Ended June 30, 2015 Six Months Ended June 30, 2015 Affected Line Items in the Statement of Operations Interest rate swap contracts $ 1,232 $ 2,459 Interest expense Foreign currency translation adjustment activity 63,207 63,207 (Loss) gain on sale of properties Realized gain on available for sale securities — (3,080 ) Interest and other income $ 64,439 $ 62,586

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes We have elected to be taxed as a REIT under the Internal Revenue Code of 1986, as amended, and are generally not subject to federal and state income taxes provided we distribute a sufficient amount of our taxable income to our shareholders and meet other requirements for qualifying as a REIT. Federal income tax expense for the three and six months ended June 30, 2015 relates to taxes incurred incurred as a result of a taxable built-in gain triggered by the sale of a property that was previously owned by a C corporation. We are also subject to certain state, local and Australian taxes without regard to our REIT status. Our provision for income taxes consists of the following (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Current: State $ 90 $ 227 $ 180 $ 261 Federal 525 — 525 — Foreign 2,450 681 2,404 1,202 3,065 908 3,109 1,463 Deferred: Foreign (150 ) — (755 ) — (150 ) — (755 ) — Income tax expense $ 2,915 $ 908 $ 2,354 $ 1,463

Derivative Instruments

Derivative Instruments	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments	Derivative Instruments Risk Management Objective of Using Derivatives We are exposed to certain risks relating to our ongoing business operations, including the effect of changes in foreign currency exchange rates and interest rates. The only risk we currently manage by using derivative instruments is a part of our interest rate risk. We may use derivative financial instruments, including interest rate swaps, caps, options, floors and other interest rate derivative contracts, to hedge all or a portion of the interest rate risk associated with our borrowings. The principal objective of such arrangements is to minimize the risks and/or costs associated with our operating and financial structure as well as to hedge specific anticipated transactions. We do not intend to utilize derivatives for speculative or other purposes other than interest rate risk management. The use of derivative financial instruments carries certain risks, including the risk that the counterparties to these contractual arrangements are not able to perform under the agreements. To mitigate this risk, we only enter into derivative financial instruments with counterparties with high credit ratings and with major financial institutions with which we and our affiliates may also have other financial relationships. We do not anticipate that any of the counterparties will fail to meet their obligations. Cash Flow Hedges of Interest Rate Risk Our objectives in using interest rate derivatives are to add stability to interest expense and to manage our exposure to interest rate movements. To accomplish this objective, we periodically use interest rate swaps, caps, or other similar instruments as part of our 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 us making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and that qualify as cash flow hedges is recorded in accumulated other comprehensive income and is subsequently reclassified into earnings in the period that the hedged forecasted transaction affects earnings. During 2015, such derivatives were used to hedge the variable cash flows associated with variable-rate debt. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings. Amounts reported in cumulative other comprehensive loss related to derivatives will be reclassified to interest expense as interest payments are made on our variable-rate debt. During the next twelve months, we estimate that an additional $4.5 million will be reclassified from cumulative other comprehensive loss as an increase to interest expense. We have interest rate swap agreements to manage our interest rate risk exposure on $170.6 million of mortgage debt due 2019, which require interest at a spread over LIBOR . The interest rate swap agreements utilized by us qualify as cash flow hedges and effectively modify our exposure to interest rate risk by converting our floating interest rate debt to a fixed interest rate basis for this loan through December 1, 2016, thus reducing the impact of interest rate changes on future interest expense. As of June 30, 2015 , we had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk: Interest Rate Derivative Number of Instruments Notional Amount (in thousands) Interest rate swap 2 $170,573 The table below presents the fair value of our derivative financial instruments as well as their classification on the condensed consolidated balance sheets as of June 30, 2015 and December 31, 2014 (amounts in thousands): Fair Value as of Interest Rate Derivative Designated as Hedging Instrument Balance Sheet Location June 30, December 31, Pay-fixed swaps Accounts payable and accrued expenses $ 5,963 $ 7,462 The table below details the location in the financial statements of the gain or loss recognized on interest rate derivatives designated as cash flow hedges for the three and six months ended June 30, 2015 and 2014 (amounts in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Balance at beginning of period $ (6,921 ) $ (10,706 ) $ (7,462 ) $ (11,706 ) Amount of loss recognized in cumulative other comprehensive loss (274 ) (632 ) (960 ) (861 ) Amount of loss reclassified from cumulative other comprehensive loss into interest expense 1,232 1,259 2,459 2,488 Unrealized gain on derivative instruments 958 627 1,499 1,627 Balance at end of period $ (5,963 ) $ (10,079 ) $ (5,963 ) $ (10,079 ) Credit-risk-related Contingent Features We have agreements with each of our derivative counterparties that contain a provision where if we either default or are capable of being declared in default on any of our indebtedness, then we could also be declared in default on our derivative obligations. As of June 30, 2015 , the fair value of derivatives in a net liability position including accrued interest but excluding any adjustment for nonperformance risk related to these agreements was $6.5 million . As of June 30, 2015 , we have not posted any collateral related to these agreements and were not in breach of any agreement provisions. If we had breached any of these provisions, we could have been required to settle our obligations under the agreements at their aggregate termination value of $6.5 million at June 30, 2015 .

Share-Based Compensation

Share-Based Compensation	6 Months Ended
	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Share-Based Compensation	Share-Based Compensation Equity Commonwealth 2015 Omnibus Incentive Plan On June 16, 2015, at our 2015 annual meeting of shareholders, our shareholders approved the Equity Commonwealth 2015 Omnibus Incentive Plan (the 2015 Incentive Plan). The 2015 Incentive Plan replaced the Equity Commonwealth 2012 Equity Compensation Plan (as amended, the 2012 Plan). The Board of Trustees approved the 2015 Incentive Plan, subject to shareholder approval, on March 18, 2015 (the Effective Date). The following description of certain terms of the 2015 Incentive Plan is qualified in all respects by the terms of the 2015 Incentive Plan. Eligibility. Awards may be granted under the 2015 Incentive Plan to employees, officers and non-employee directors of the Company, its subsidiaries or its affiliates, or consultants and advisors (who are natural persons) providing services to the Company, its subsidiaries or its affiliates, or any other person whose participation in the 2015 Incentive Plan is determined by the Compensation Committee to be in the best interests of the Company. Term . The 2015 Incentive Plan terminates automatically ten years after the Effective Date, unless it is terminated earlier by the Board of Trustees. Shares Available for Issuance. Subject to adjustment as provided in the 2015 Incentive Plan, the maximum number of common shares of the Company that are available for issuance under the 2015 Incentive Plan is 3,250,000 shares. Awards. The following types of awards may be made under the 2015 Incentive Plan, subject to limitations set forth in the 2015 Incentive Plan: · Stock options; · Stock appreciation rights; · Restricted stock; · Restricted stock units; · Unrestricted stock; · Dividend equivalent rights; · Performance shares and other performance-based awards; · Limited partnership interests in any partnership entity through which the Company may conduct its business in the future; · Other equity-based awards; and · Cash bonus awards. Recipients of the Company’s restricted shares have the same voting rights as any other common shareholder. During the period of restriction, the Company’s unvested restricted shareholders are eligible to receive dividend payments on their shares at the same rate and on the same date as any other common shareholder. Recipients of the Company’s restricted stock units (RSUs) are entitled to receive dividends with respect to the common shares underlying the RSUs if and when the RSUs are earned, at which time the recipient will be entitled to receive an amount in cash equal to the aggregate amount of ordinary cash dividends that would have been paid in respect of the common shares underlying the recipient’s earned RSUs had such common shares been issued to the recipient on the first day of the performance period. Administration. The 2015 Incentive Plan will be administered by the Compensation Committee, which will determine all terms and recipients of awards under the 2015 Incentive Plan. 2012 Equity Compensation Plan In the past, the Company has granted equity-based compensation under the 2012 Plan. The 2012 Plan authorized grants of the Company’s restricted common shares and RSUs. The 2015 Incentive Plan replaced the 2012 Plan. No future grants will be made under the 2012 Plan, although the terms and conditions of the 2012 Plan will continue to govern any outstanding awards granted under the 2012 Plan. 2015 Equity Award Activity On June 16, 2015, in accordance with the Company’s compensation plan for independent Trustees, the Committee awarded each of the nine independent Trustees $0.1 million in restricted shares as part of their compensation for the 2015-2016 year of service on the Board of Trustees. These awards equated to 3,843 shares per Trustee, for a total of 34,587 shares, valued at $26.02 per share, the closing price of our common shares on the NYSE on that day. These shares vest one year after the date of the award. During the three and six months ended June 30, 2015, due to employee terminations, 8,115 restricted shares were forfeited with an average per share fair value at grant date of $26.64 , and 16,475 RSUs were forfeited with an average per share fair value at grant date of $20.50 . Equity Grants for 2014 Performance On January 28, 2015, the Committee approved a grant of 126,319 restricted common shares and 256,467 RSUs at target to the Company’s officers, certain employees and to Mr. Zell, the Chairman of our Board of Trustees, as part of their compensation for fiscal year 2014. The restricted shares are service based awards and vest over a four -year period. The restricted shares were granted on January 28, 2015 and were valued at $26.58 per share, the closing price of our common shares on the NYSE on that day. As of June 30, 2015 , the estimated future compensation expense for all unvested restricted share grants was $17.5 million . Compensation expense for the restricted share awards is being recognized on a straight-line basis over the requisite service period for each separately vesting portion of the award. The weighted average period over which the compensation expense will be recorded for the restricted shares is approximately 3.3 years. The RSUs are market based awards with a service condition and grant recipients may earn between 0% - 100% of the RSU grant based on the Company’s total shareholder return (TSR) relative to the TSR's for the constituent REITs that comprise the NAREIT Office Index for the performance period of January 28, 2015 - January 28, 2018. Following the end of the performance period on January 28, 2018, the number of earned awards will be determined. The earned awards vest in two tranches with 50% of the earned award vesting on January 28, 2018 and the remaining 50% of the earned award vesting on January 28, 2019, subject to the grant recipient’s continued employment. Recipients of the Company’s RSUs are entitled to receive dividends with respect to the common shares underlying the RSUs if and when the RSUs are earned. To the extent that an award does not vest, the dividends will be forfeited. Compensation expense for the RSU awards was determined using a Monte Carlo simulation model and is being recognized ratably from the grant date to the vesting date of each tranche. As of June 30, 2015 , the estimated future compensation expense for all unvested RSUs was $25.0 million . The weighted average period over which the compensation expense will be recorded for the RSUs is approximately 2.9 years. The assumptions and fair values for the RSUs granted for the six months ended June 30, 2015 are included in the following table on a per share basis. 2015 Fair value of RSUs granted $ 38.55 Expected term (years) 4 Expected volatility — Expected dividend yield 1.88 % Risk-free rate 0.81 % During the three and six months ended June 30, 2015 , we recorded $4.1 million and $8.1 million , respectively, of compensation expense, net of forfeitures, in general and administrative expense for grants to our Board of Trustees and the Company's employees related to our Plan. At June 30, 2015 , 3,215,413 common shares remain available for issuance under the Plan. Prior Equity Grants: As a result of the removal of our former Trustees on March 25, 2014, the vesting of 130,914 common shares previously issued to our former officers and certain employees of RMR pursuant to our equity compensation plans accelerated in accordance with the terms of their governing share grants. During the six months ended June 30, 2014 , we recorded $3.4 million of general and administrative expense related to the vesting of these shares.

Fair Value of Assets and Liabil

Fair Value of Assets and Liabilities	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Fair Value of Assets and Liabilities	Fair Value of Assets and Liabilities The table below presents certain of our assets and liabilities measured at fair value during 2015 , categorized by the level of inputs used in the valuation of each asset and liability (dollars in thousands): Fair Value at June 30, 2015 Using Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Description Total (Level 1) (Level 2) (Level 3) Recurring Fair Value Measurements: Effective portion of interest rate swap contracts $ (5,963 ) $ — $ (5,963 ) $ — Derivative liability (8,919 ) — — (8,919 ) Effective Portion of Interest Rate Swap Contracts The fair value of our interest rate swap contracts is determined using the net discounted cash flows of each derivative based on the market based interest rate curve (level 2 inputs) and adjusted for our credit spread and the actual and estimated credit spreads of the counterparties (level 3 inputs). Although we have determined that the majority of the inputs used to value our derivatives fall within level 2 of the fair value hierarchy, the credit valuation adjustments associated with our derivatives utilize level 3 inputs, such as estimates of current credit spreads, to evaluate the likelihood of default by us and the counterparties. As of June 30, 2015 , we have assessed the significance of the impact of the credit valuation adjustments on the overall valuation of our derivative positions and have determined that the credit valuation adjustments are not significant to the overall valuation of our derivatives. As a result, we have determined that our derivative valuations in their entirety are classified as level 2 inputs in the fair value hierarchy. Derivative Liability On July 31, 2014, our shareholders voted to approve the reimbursement of expenses incurred by Related/Corvex (Note 17). Approximately $8.4 million will be reimbursed only if the average closing price of our common shares is at least $26.00 (as adjusted for any share splits or share dividends) during the one year period after the date on which the reimbursement was approved by shareholders, and the remaining approximately $8.4 million will be reimbursed only if the average closing price of our common shares is at least $26.00 (as adjusted for any share splits or share dividends) during the one year period between the first and second anniversaries of the date on which the reimbursement was approved by shareholders. The potential future reimbursement represents a derivative instrument as codified in ASC 815 Derivatives and Hedging which requires the potential future reimbursement to be recorded at fair value at each reporting date. The fair value of the derivative liability as of March 31, 2015 and December 31, 2014 was $(9.3) million and $(6.7) million , respectively. The change in the fair value was recorded in general and administrative expenses in our condensed consolidated statement of operations for the three and six months ended June 30, 2015 . The valuation techniques and significant unobservable inputs used for our level 3 fair value measurement at June 30, 2015 were as follows: Description Fair Value at June 30, 2015 Primary Valuation Technique Unobservable Inputs Rate Derivative liability $ (8,919 ) Monte Carlo simulation Risk-free rate 0.30% Volatility 20.0% Financial Instruments In addition to the assets and liabilities described in the above table, our financial instruments include our cash and cash equivalents, real estate mortgages receivable, restricted cash, senior unsecured debt and mortgage notes payable. At June 30, 2015 and December 31, 2014, the fair value of these additional financial instruments were not materially different from their carrying values, except as follows (in thousands): June 30, 2015 December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value Senior unsecured debt and mortgage notes payable, net $ 1,973,692 $ 2,033,171 $ 2,207,665 $ 2,263,535 The fair values of our senior notes and mortgage notes payable are based on estimates using discounted cash flow analyses and currently prevailing interest rates adjusted by credit risk spreads (level 3 inputs). Other financial instruments that potentially subject us to concentrations of credit risk consist principally of rents receivable; however, as of June 30, 2015 , no single tenant of ours is responsible for more than 3% of our total annualized rents. Our derivative financial instruments, including interest rate swaps, are entered with major financial institutions and we monitor the amount of credit exposure to any one counterparty. In July 2015, we transferred approximately $218.0 million in U.S. dollars from our Australian subsidiary to our U.S. bank accounts. As a result of these transfers, we expect to recognize foreign currency exchange losses of approximately $9.5 million in our third quarter 2015 consolidated financial statements. As of August 6, 2015, the Australia dollar cash and cash equivalents balance was approximately $7.0 million in U.S. dollars.

Earnings Per Common Share

Earnings Per Common Share	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Earnings Per Common Share	Earnings Per Common Share The following table sets forth the computation of basic and diluted earnings per share (amounts in thousands except per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator for earnings per common share - basic and diluted: Income from continuing operations $ 12,616 $ 6,688 $ 26,246 $ 23,413 Preferred distributions (6,981 ) (6,982 ) (13,962 ) (18,133 ) Excess fair value of consideration over carrying vale of preferred shares — (16,205 ) — (16,205 ) Income (loss) from continuing operations attributable to Equity Commonwealth common shareholders 5,635 (16,499 ) 12,284 (10,925 ) Discontinued operations — (1,303 ) — 2,420 Numerator for net income (loss) per share - basic and diluted $ 5,635 $ (17,802 ) $ 12,284 $ (8,505 ) Denominator for earnings per common share - basic and diluted: Weighted average number of common shares outstanding - basic 129,733 123,812 129,714 121,121 Weighted average number of common shares outstanding - diluted (1) 130,537 123,812 130,205 121,121 Earnings per share - basic and diluted: Income (loss) from continuing operations attributable to Equity Commonwealth common shareholders $ 0.04 $ (0.13 ) $ 0.09 $ (0.09 ) Discontinued operations — (0.01 ) — 0.02 Net income (loss) per share - basic and diluted $ 0.04 $ (0.14 ) $ 0.09 $ (0.07 ) Anti-dilutive securities: Effect of Series D preferred shares; 6 1/2% cumulative convertible (2) 2,363 4,721 2,363 6,017 (1) As of June 30, 2015 , we had granted RSUs to certain employees, officers, and the chairman of the Board of Trustees. The RSUs contain both service and market-based vesting components. None of the RSUs have vested. If the market-based vesting component was measured as of June 30, 2015 , 803 common shares would be issued to the RSU holders, and no shares would have been issued for the other periods presented. Using a weighted average basis, 804 and 491 common shares are reflected in diluted earnings per share for the three and six months ended June 30, 2015, respectively. (2) The Series D preferred shares are excluded from the diluted earnings per share calculation because including the Series D preferred shares would also require that the preferred distributions be added back to net income, resulting in anti-dilution during the periods presented.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Segment Information	Segment Information Our primary business is the ownership and operation of office properties. We account for each of our individual properties as a separate operating segment. We have aggregated our separate operating segments into two reportable segments based on our primary method of internal reporting: CBD properties and suburban properties. More than 90% of our CBD and suburban properties are office properties. Our operating segments (i.e., our individual properties) are managed and operated consistently in accordance with our standard operating procedures. We use property net operating income, or NOI, to evaluate the performance of our operating segments. We define NOI as income from our real estate including lease termination fees received from tenants less our property operating expenses. NOI excludes amortization of capitalized tenant improvement costs and leasing commissions. As of June 30, 2015 , we owned 29 CBD properties ( 41 buildings) and 57 suburban properties ( 135 buildings), excluding assets held for sale as of June 30, 2015. Property level information by operating segment as of June 30, 2015 , and for the three and six months ended June 30, 2015 and 2014 , is as follows (in thousands): As of June 30, 2015 2014 Square feet: CBD properties 15,769 21,892 Suburban properties 13,616 21,028 Total properties(1) 29,385 42,920 (1) Square footage of properties owned as of the respective dates. Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Rental income: CBD properties $ 108,349 $ 106,094 $ 218,192 $ 216,333 Suburban properties 55,348 66,313 113,477 128,114 Total properties $ 163,697 $ 172,407 $ 331,669 $ 344,447 Tenant reimbursements and other income: CBD properties $ 27,683 $ 28,465 $ 57,380 $ 58,706 Suburban properties 12,314 14,322 27,700 29,301 Total properties $ 39,997 $ 42,787 $ 85,080 $ 88,007 NOI: CBD properties $ 75,566 $ 71,996 $ 149,513 $ 145,166 Suburban properties 38,442 50,497 79,679 92,856 Total properties $ 114,008 $ 122,493 $ 229,192 $ 238,022 As of June 30, 2015 , our investments in CBD properties and suburban properties, net of accumulated depreciation, were $2,182.7 million and $1,195.5 million , respectively. The following table includes the reconciliation of NOI to net income, the most directly comparable financial measure under GAAP reported in our condensed consolidated financial statements. We consider NOI to be an appropriate supplemental measure to net income because it may help both investors and management to understand the operations of our properties. We use NOI internally to evaluate individual, regional and combined property level performance, and we believe that NOI provides useful information to investors regarding our results of operations because it reflects only those income and expense items that are incurred at the property level and may facilitate comparisons of our operating performance between periods and with other REITs. NOI does not represent cash generated by operating activities in accordance with GAAP and should not be considered as an alternative to net income, net income attributable to Equity Commonwealth common shareholders, operating income or cash flow from operating activities, determined in accordance with GAAP, or as an indicator of our financial performance or liquidity, nor is this measure necessarily indicative of sufficient cash flow to fund all of our needs. This measure should be considered in conjunction with net income, net income attributable to Equity Commonwealth common shareholders, operating income and cash flow from operating activities as presented in our condensed consolidated statements of operations, condensed consolidated statements of comprehensive income and condensed consolidated statements of cash flows. Other REITs and real estate companies may calculate NOI differently than we do. A reconciliation of NOI to net income for the three and six months ended June 30, 2015 and 2014 , is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Rental income $ 163,697 $ 172,407 $ 331,669 $ 344,447 Tenant reimbursements and other income 39,997 42,787 85,080 88,007 Operating expenses (89,686 ) (92,701 ) (187,557 ) (194,432 ) NOI $ 114,008 $ 122,493 $ 229,192 $ 238,022 NOI $ 114,008 $ 122,493 $ 229,192 $ 238,022 Depreciation and amortization (53,637 ) (59,831 ) (116,336 ) (111,480 ) General and administrative (10,911 ) (24,097 ) (27,469 ) (48,945 ) Loss on asset impairment (15,258 ) (22,683 ) (17,162 ) (17,922 ) Acquisition related costs — — — (5 ) Operating income 34,202 15,882 68,225 59,670 Interest and other income 728 281 4,176 665 Interest expense (27,973 ) (37,899 ) (57,815 ) (75,834 ) Gain on early extinguishment of debt 10,426 — 9,998 — Loss on sale of equity investments — (33 ) — (33 ) Gain on issuance of shares by an equity investee — 16,911 — 17,020 Foreign currency exchange gain 856 — 856 — (Loss) gain on sale of properties (2,708 ) — 3,160 — Income (loss) from continuing operations before income taxes and equity in earnings of investees 15,531 (4,858 ) 28,600 1,488 Income tax expense (2,915 ) (908 ) (2,354 ) (1,463 ) Equity in earnings of investees — 12,454 — 23,388 Income from continuing operations 12,616 6,688 26,246 23,413 Income from discontinued operations — 4,114 — 8,125 Loss on asset impairment from discontinued operations — (2,072 ) — (2,360 ) Loss on early extinguishment of debt from discontinued operations — (3,345 ) — (3,345 ) Net income $ 12,616 $ 5,385 $ 26,246 $ 25,833

Related Person Transactions

Related Person Transactions	6 Months Ended
	Jun. 30, 2015
Related Party Transactions [Abstract]
Related Person Transactions	Related Person Transactions The following discussion includes a description of our related person transactions for the three and six months ended June 30, 2015 and 2014 . Certain of these related person transactions, and their approvals, occurred prior to the election of our new Board of Trustees at the Special Meeting and the appointment of our current executive officers following the Special Meeting. The disclosure below under “—Transactions with Prior Related Persons” describes our transactions and approvals with our prior related persons. Related Person Transactions Following the Special Meeting: Equity Group Investments and associated entities: Effective July 20, 2015, we entered into a lease with Two North Riverside Plaza Joint Venture Limited Partnership, an entity associated with Mr. Zell, our Chairman, to occupy office space on the twentieth and twenty-first floors of Two North Riverside Plaza in Chicago, Illinois. The initial term of the lease is approximately five years, with one 5 -year renewal option. The lease payment is approximately $0.5 million for the initial year beginning in 2016, and $0.8 million annually thereafter. This lease was approved by the Audit Committee of the Board of Trustees on June 16, 2015. Effective June 1, 2014, we entered into a one -year license agreement with Equity Group Investments, a private investment firm (Equity Group), to use office space on the sixth floor at Two North Riverside Plaza in Chicago, Illinois. The license fee was $0.2 million for the initial year. The license fee includes the non-exclusive use of additional areas on the sixth floor (such as conference rooms and common areas), certain administrative services (such as mail room services and reception desk staffing), office equipment, office furniture, supplies, licensee’s share of building operating expenses and real estate taxes and access to one parking space. Mr. Zell, our Chairman, is the Chairman and Chief Executive Officer of Equity Group, and Mr. Helfand, our President and Chief Executive Officer, is the Co-President of Equity Group. This license agreement was approved by the Audit Committee of the Board of Trustees and was scheduled to expire on May 31, 2015. On May 4, 2015, the Audit Committee of the Board of Trustees approved an agreement to extend the term of the license agreement through November 30, 2015. The license fee payment is approximately $0.1 million for the extended term. Effective June 1, 2014, we entered into a one -year lease with one 3 -month renewal option with Two North Riverside Plaza Joint Venture Limited Partnership, an entity associated with Mr. Zell, our Chairman, to occupy office space on the fourteenth floor at Two North Riverside Plaza in Chicago, Illinois. The lease payment was $0.2 million for the initial term. This lease was terminated, effective January 31, 2015. This lease was approved by the Audit Committee of the Board of Trustees. Effective July 31, 2014, we entered into a sublease with Equity Residential Management, L.L.C. to occupy office space on the tenth floor of Two North Riverside Plaza in Chicago, Illinois. Equity Residential Management, L.L.C. leases the space from Two North Riverside Plaza Joint Venture Limited Partnership, an entity associated with Mr. Zell, our Chairman. The initial term of the sublease was approximately seven months commencing on or about October 22, 2014, expiring on May 31, 2015, with one 3 -month renewal option. The sublease payment was approximately $0.2 million for the initial term. This sublease was approved by the Audit Committee of the Board of Trustees. On May 4, 2015, the Audit Committee of the Board of Trustees approved an agreement to extend the term of the sublease through November 30, 2015. The sublease payment is approximately $0.2 million for the extended term. Related/Corvex: On July 31, 2014, at the reconvened session of our 2014 annual meeting of shareholders, our shareholders voted to approve the reimbursement of approximately $33.5 million of expenses incurred by Related/Corvex since February 2013 in connection with their consent solicitations to remove our former Trustees and elect the new Board of Trustees and to engage in related litigation. Approximately $16.7 million was paid during the year ended December 31, 2014. Approximately $8.4 million will be reimbursed only if the average closing price of our common shares is at least $26.00 (as adjusted for any share splits or share dividends) during the one year period after the date on which the reimbursement was approved by shareholders, and the remaining approximately $8.4 million will be reimbursed only if the average closing price of our common shares is at least $26.00 (as adjusted for any share splits or share dividends) during the one year period between the first and second anniversaries of the date on which the reimbursement was approved by shareholders. The closing price of our common shares was at least $26.00 during the first one year period after the date on which the reimbursement was approved by shareholders, and in August 2015, we paid $8.4 million to Related/Corvex. Transactions with Prior Related Persons: RMR : Prior to entering into the Termination and Cooperation Agreement with RMR, as further described below, we had three primary agreements with RMR and its affiliates to provide management and administrative services to us: (i) a business management agreement, which relates to our business generally, (ii) a property management agreement, which relates to our property level operations, and (iii) an Australia business and property management agreement, which relates to our Australian properties. During the time we were externally managed by RMR, one of our former Managing Trustees, Mr. Barry Portnoy, was Chairman, majority owner and an employee of RMR. Another former Managing Trustee and our former President, Mr. Adam Portnoy, is the son of Mr. Barry Portnoy, and was an owner, President, Chief Executive Officer and a director of RMR. As a result of the removal, effective March 25, 2014, of Mr. Barry Portnoy and Mr. Adam Portnoy as Trustees of the Company and the resignation on May 23, 2014, of Mr. Adam D. Portnoy, Mr. John C. Popeo, Mr. David M. Lepore and other officers of RMR from their respective positions as officers of the Company, they, RMR, RMR Australia Asset Management Pty Limited, or RMR Australia, SIR and AIC have ceased to be related persons of the Company. Therefore, we only present related person transactions with these entities through June 30, 2014. Pursuant to our business management agreement with RMR, we recognized business management fee expense of $16.3 million and $31.7 million for the three and six months ended June 30, 2014 , respectively. The fees for the three and six months ended June 30, 2014 , include estimated 2014 incentive fees payable in common shares based on our common share total return. These amounts are included in general and administrative expenses, in our condensed consolidated financial statements. In accordance with the terms of our business management agreement, as amended in December 2013, we issued 68,206 of our common shares to RMR for the six months ended June 30, 2014 as payment for 10% of the base business management fee we recognized for such period. In connection with our property management agreement with RMR, the aggregate property management and construction supervision fees we recognized were $6.8 million and $13.8 million for the three and six months ended June 30, 2014 , respectively. These amounts are included in operating expenses or have been capitalized, as appropriate, in our condensed consolidated financial statements. Our contract with MacarthurCook Fund Management Limited (MacarthurCook) terminated on January 31, 2013, and on that date we entered into a business and property management agreement (Australia Management Agreement) with RMR Australia for the benefit of CWH Australia Trust (formerly the MacarthurCook Industrial Property Fund), a subsidiary of ours. The terms of the Australia Management Agreement are substantially similar to the terms of the management agreement we had with MacarthurCook. RMR Australia is owned by our former Managing Trustees and our former President and it has been granted an Australian financial services license by the Australian Securities & Investments Commission. Similar to our prior arrangement with respect to fees we paid to MacarthurCook, RMR has agreed to waive half of the fees payable by us under our property management agreement with RMR and half of the business management fees otherwise payable by us under our business management agreement with RMR related to real estate investments that are subject to the Australia Management Agreement for so long as the Australia Management Agreement is in effect and we or any of our subsidiaries are paying the fees under that agreement. Pursuant to the Australia Management Agreement, we recognized aggregate business and property management fee expense of $0.4 million and $0.9 million for the three and six months ended June 30, 2014 , respectively, which amounts are equal to the fees waived by RMR and excluded from the amount that was payable to RMR during the three and six months ended June 30, 2014 , respectively. Termination and Cooperation Agreement: On September 30, 2014, we entered into a termination and cooperation agreement (Cooperation Agreement) with RMR and RMR Australia together, (Manager). Under the terms of the agreement, the existing business and property management agreements with RMR terminated effective September 30, 2014. Pursuant to the Cooperation Agreement, through February 28, 2015, Manager agreed to use best efforts to assist us in the transition of our management and operations. We paid Manager $1.2 million per month for transition services from October 1, 2014 to February 28, 2015. The payment of the transition fee also covered continued management and other services for the Australian assets. RMR continues to manage our Australian assets pursuant to an existing management agreement, which is scheduled to terminate no later than January 31, 2016. Beginning March 1, 2015, we have agreed to pay Manager $0.1 million per month until we no longer require such services or until the Australia Management Agreement is terminated. There is no future obligation to pay an incentive fee to RMR. SIR : SIR was formerly our 100% owned subsidiary. In March 2012, SIR completed an initial public offering, or the SIR IPO. As of June 30, 2014 , we owned 22,000,000 common shares of SIR, which represented approximately 44.1% of SIR’s outstanding common shares. On July 9, 2014, we sold our entire stake of 22,000,000 common shares of SIR, for $32.04 per share, raising aggregate gross proceeds of $704.8 million . As a result of this sale, we no longer hold any interest in SIR. AIC : We previously owned 12.5% of AIC, an Indiana insurance company, and, as of May 9, 2014, had invested $5.2 million in AIC since we became an equity owner of AIC in 2009. RMR, SIR and five other companies to which RMR provides management services also own shares of AIC. The other shareholders of AIC, on May 9, 2014, exercised their right to purchase the 20,000 shares of AIC we then owned. We received $5.8 million in aggregate proceeds from this sale and we no longer own any interest in AIC. We previously purchased property insurance providing $500.0 million of coverage pursuant to an insurance program arranged by AIC and with respect to which AIC was a reinsurer of certain coverage amounts. This program expired in June 2014. Indemnification : Pursuant to our declaration of trust and separate indemnification agreements, we have advanced amounts incurred for legal fees and costs on behalf of certain of the former Trustees and officers with respect to the legal proceedings described in Part II, Item 1, “Legal Proceedings” in this Quarterly Report. Pursuant to indemnification provisions in our business and property management agreements with RMR, we have also incurred legal fees and costs on behalf of RMR for claims brought against RMR in its capacity as our business and property manager with respect to certain legal proceedings described in Part II, Item 1, “Legal Proceedings” in this Quarterly Report. For the three and six months ended June 30, 2014 , we incurred approximately $1.5 million and $5.4 million , respectively, in such legal fees and costs.

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2015
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On August 4, 2015, we sold Illinois Center ( two buildings), with 2,090,162 square feet for $376.0 million and on August 3, 2015, we defeased the outstanding $141.4 million balance of the mortgage loan secured by 111 East Wacker Drive, one of the buildings included in Illinois Center. On July 31, 2015, we entered into a settlement agreement with Jason Katz, Central Laborers' Pension Fund and certain other named plaintiffs to resolve two previously disclosed actions against us and certain of our former officers and former Trustees. We have agreed to pay $0.2 million to the plaintiffs' counsel for a portion of the costs and expenses incurred in connection with those two actions. On July 24, 2015, we entered into a settlement agreement with William Gore to resolve a previously disclosed action against certain of our former officers and former Trustees. We have agreed to pay $0.1 million to the plaintiffs' counsel for a portion of the costs and expenses incurred in connection with the action. On July 17, 2015, we entered into a settlement agreement with Delaware County Employees Retirement Fund and certain other named plaintiffs to resolve two previously disclosed actions against certain of our former officers and former Trustees and the Company's former external manager, RMR. We have agreed to pay $0.1 million to the plaintiffs' counsel for a portion of the costs and expenses incurred in connection with those actions.

Basis of Presentation (Policies

Basis of Presentation (Policies)	6 Months Ended
	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The accompanying condensed consolidated financial statements of EQC have been prepared without audit. Certain information and footnote disclosures required by U.S. generally accepted accounting principles, or GAAP, for complete financial statements have been condensed or omitted. We believe the disclosures made are adequate to make the information presented not misleading. However, the accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes contained in our Annual Report on Form 10-K (Annual Report) for the year ended December 31, 2014. Capitalized terms used, but not defined in this Quarterly Report, have the same meanings as in our Annual Report. In the opinion of our management, all adjustments, which include only normal recurring adjustments considered necessary for a fair presentation, have been included. All intercompany transactions and balances with or among our subsidiaries have been eliminated. Operating results for interim periods are not necessarily indicative of the results that may be expected for the full year. Reclassifications have been made to the prior years’ financial statements to conform to the current year’s presentation. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect reported amounts. Actual results could differ from those estimates. Significant estimates in the condensed consolidated financial statements include the allowance for doubtful accounts, purchase price allocations, useful lives of fixed assets and impairment of real estate and intangible assets. Share amounts are presented in whole numbers, except where noted.
Recent Accounting Pronouncements	In April 2014, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity, or ASU 2014-08. ASU 2014-08 changes the criteria for reporting a discontinued operation. Under the new pronouncement, a disposal of a part of an organization that has a major effect on its operations and financial results is a discontinued operation. We adopted ASU 2014-08 on January 1, 2015, and determined that our individual 2015 dispositions and properties held for sale as of June 30, 2015 do not represent a strategic shift, as defined by the standard, that has or will have a major effect on our operations and financial results. In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers, which provides guidance for revenue recognition. This update is effective for interim and annual reporting periods beginning after December 15, 2017. We are currently in the process of evaluating the impact, if any, the adoption of this ASU will have on our condensed consolidated financial statements. In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs. This standard amends existing guidance to require the presentation of debt issuance costs in the balance sheet as a deduction from the carrying amount of the related debt liability instead of as a deferred charge. It is effective for annual reporting periods beginning after December 15, 2015, but early adoption is permitted. We do not expect that the adoption of this standard will have a material impact on our condensed consolidated financial statements.

Real Estate Properties (Tables)

Real Estate Properties (Tables)	6 Months Ended
	Jun. 30, 2015
Real Estate [Abstract]
Summary of Balance Sheet Information for all Properties Classified as Held for sale	Summarized balance sheet information for all properties classified as held for sale is as follows (in thousands): June 30, 2015 Real estate properties $ 341,263 Acquired real estate leases 13,238 Other assets, net 6,280 Properties held for sale $ 360,781 Accounts payable and accrued expenses $ 12,387 Assumed real estate lease obligations 6,516 Rent collected in advance 113 Security deposits 1,320 Liabilities related to properties held for sale $ 20,336
Summary of Properties Sold and Income Statement Information for Properties Disposed of	Summarized income statement information for properties included in discontinued operations is as follows (in thousands): Three Months Ended Six Months Ended June 30, 2014 Rental income $ 6,962 $ 14,236 Tenant reimbursements and other income 801 1,323 Total revenues 7,763 15,559 Operating expenses 3,375 6,854 General and administrative — 3 Total expenses 3,375 6,857 Operating income 4,388 8,702 Interest expense (274 ) (577 ) Income from discontinued operations $ 4,114 $ 8,125 During the six months ended June 30, 2015 , we disposed of the following properties (dollars in thousands): Asset Date Disposed Segment Number of Number of Square Footage Gross Sales Price Gain (Loss) on Sale Properties 11350 North Meridian Street January 2015 Suburban 1 1 72,264 $ 4,200 $ 766 333 Laurel Oak Drive (1) March 2015 Suburban — 1 27,164 2,450 251 1921 E. Alton Avenue March 2015 Suburban 1 1 67,846 14,533 4,851 46 Inverness Center Parkway April 2015 Suburban — — — 2,000 1,857 225 Water Street (2) May 2015 CBD 1 1 318,997 — — Sorrento Valley Business Park June 2015 Suburban 1 4 105,003 23,500 11,896 Portfolio of properties 7450 Campus Drive May 2015 Suburban 1 1 77,411 129 Worthington Ridge Road May 2015 Suburban 1 1 227,500 599 Research Parkway May 2015 Suburban 1 1 48,249 181 Marsh Hill Road May 2015 Suburban 1 1 162,036 101 Barnes Road May 2015 Suburban 1 1 45,755 15 Sterling Drive May 2015 Suburban 1 1 173,015 35 Thorpe Avenue May 2015 Suburban 1 1 79,862 50 Barnes Industrial Road North May 2015 Suburban 1 1 154,255 5-9 Barnes Industrial Road May 2015 Suburban 1 1 38,006 860 North Main Street May 2015 Suburban 1 1 31,165 One Barnes Industrial Road South May 2015 Suburban 1 1 30,170 Village Lane May 2015 Suburban 1 2 58,185 100 Northfield Drive May 2015 Suburban 1 1 116,986 905 Meridian Lake Drive May 2015 Suburban 1 1 74,652 1717 Deerfield Road May 2015 Suburban 1 1 141,186 1955 West Field Court May 2015 Suburban 1 1 59,130 5015 S. Water Circle May 2015 Suburban 1 1 113,524 Adams Place May 2015 Suburban 1 2 230,259 Cabot Business Park May 2015 Suburban 1 2 252,755 2300 Crown Colony Drive May 2015 Suburban 1 1 45,974 Myles Standish Industrial Park May 2015 Suburban 1 2 74,800 340 Thompson Road May 2015 Suburban 1 1 25,000 100 South Charles Street May 2015 CBD 1 1 159,616 6710 Oxon Hill May 2015 Suburban 1 1 118,336 8800 Queen Avenue South May 2015 Suburban 1 1 280,822 9800 Sherlard Parkway May 2015 Suburban 1 1 46,765 Rosedale Corporate Plaza May 2015 Suburban 1 3 149,116 1000 Shelard Parkway May 2015 Suburban 1 1 62,499 525 Park Street May 2015 CBD 1 1 75,636 1900 Meyer Drury Drive May 2015 Suburban 1 1 65,225 131-165 West Ninth Street May 2015 Suburban 1 1 75,517 7-9 Vreeland Road May 2015 Suburban 1 1 155,891 5 Paragon Drive May 2015 Suburban 1 1 119,089 Asset Date Disposed Segment Number of Number of Square Footage Gross Sales Price Gain (Loss) on Sale 1000 Vorhees Drive and 400 Laurel Oak Drive(1) May 2015 Suburban 1 2 125,415 1601 Veterans Highway May 2015 Suburban 1 1 63,608 Two Corporate Center Drive May 2015 Suburban 1 1 291,230 11311 Cornell Park Drive May 2015 Suburban 1 1 93,413 5300 Kings Island Drive May 2015 Suburban 1 1 159,421 3 Crown Point Court May 2015 Suburban 1 1 73,987 515 Pennsylvania Avenue May 2015 Suburban 1 1 82,000 443 Gulph Road May 2015 Suburban 1 1 21,000 4350 Northern Pike May 2015 Suburban 1 1 503,885 Thunderbolt Place May 2015 Suburban 1 2 100,505 6160 Kempsville Circle May 2015 Suburban 1 1 129,565 448 Viking Drive May 2015 Suburban 1 1 75,374 Portfolio of small office and industrial assets 45 53 5,287,790 $ 376,000 $ (7,915 ) 2501 20th Place South June 2015 CBD 1 1 125,722 420 20th Street North June 2015 CBD 1 1 514,893 Inverness Center June 2015 Suburban 1 4 475,951 701 Poydras Street June 2015 CBD 1 1 1,256,971 300 North Greene Street June 2015 CBD 1 1 324,305 1320 Main Street June 2015 CBD 1 1 334,075 AL, LA, NC, SC office portfolio 6 9 3,031,917 $ 417,450 $ 41,596 12655 Olive Boulevard June 2015 Suburban 1 1 98,588 1285 Fern Ridge Parkway June 2015 Suburban 1 1 66,510 St. Louis portfolio 2 2 165,098 $ 14,300 $ (2,338 ) 310-314 Invermay Road (3) April 2015 Suburban 1 1 47,480 253-293 George Town Road (3) April 2015 Suburban 1 1 143,914 7 Modal Crescent June 2015 Suburban 1 1 164,160 71-93 Whiteside Road June 2015 Suburban 1 1 303,488 9-13 Titanium Court June 2015 Suburban 1 1 69,664 16 Rodborough Road June 2015 Suburban 1 1 90,525 22 Rodborough Road June 2015 Suburban 1 1 43,427 127-161 Cherry Lane June 2015 Suburban 1 1 278,570 310-320 Pitt Street June 2015 CBD 1 1 313,865 44-46 Mandarin Street June 2015 Suburban 1 1 226,718 19 Leadership Way June 2015 Suburban 1 1 76,714 Australia portfolio (4) 11 11 1,758,525 $ 232,955 $ (47,804 ) 68 83 10,834,604 $ 1,087,388 $ 3,160 (1) This property contains three buildings. We sold one building in March 2015 and two buildings in May 2015. (2) Title to this property was transferred to the lender pursuant to a consensual foreclosure in full satisfaction of the mortgage debt with a principal balance of $40.1 million , resulting in a gain on early extinguishment of debt of $17.3 million for the three and six months ended June 30, 2015. See Note 8 for additional information. (3) These properties were sold in a separate transaction to a different buyer than other Australian properties. (4) The loss on sale includes a $63.2 million cumulative foreign currency translation adjustment reclassified from cumuluative other comprehensive loss due to the disposition of the Australian portfolio.

Equity Investments (Tables)

Equity Investments (Tables)	6 Months Ended
	Jun. 30, 2015
SIR
Equity Investments
Summary of Unaudited Income Statement Information of Equity Method Investee	The following unaudited summarized income statement information of SIR as reported in SIR's Quarterly Report on Form 10-Q for the three and six months ended June 30, 2014 is as follows (in thousands, except per share data): Three Months Ended Six Months Ended June 30, 2014 Rental income $ 48,465 93,528 Tenant reimbursements and other income 8,092 16,057 Total revenues 56,557 109,585 Operating expenses 9,985 19,964 Depreciation and amortization 10,495 19,789 Acquisition related costs 136 374 General and administrative 2,198 7,374 Total expenses 22,814 47,501 Operating income 33,743 62,084 Interest expense (3,634 ) (6,992 ) Gain on early extinguishment of debt — 243 Income before income tax expense and equity in earnings of an investee 30,109 55,335 Income tax expense (19 ) (90 ) Equity in earnings of an investee 118 21 Net income $ 30,208 $ 55,266 Weighted average common shares outstanding 54,178 52,021 Net income per common share $ 0.56 $ 1.06

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2015
Stockholders' Equity Note [Abstract]
Schedule of Declared Distributions	In 2015, our Board of Trustees declared distributions on our series D preferred shares and series E cumulative redeemable preferred shares to date as follows: Declaration Date Record Date Payment Date Series D Dividend Per Share Series E Dividend Per Share January 16, 2015 February 2, 2015 February 17, 2015 $ 0.40625 $ 0.453125 April 8, 2015 May 1, 2015 May 15, 2015 $ 0.40625 $ 0.453125 July 9, 2015 July 31, 2015 August 17, 2015 $ 0.40625 $ 0.453125

Cumulative Other Comprehensiv30

Cumulative Other Comprehensive Loss (Tables)	6 Months Ended
	Jun. 30, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Amounts Recognized in Cumulative Other Comprehensive Loss	The following tables present the amounts recognized in cumulative other comprehensive loss by component for the three and six months ended June 30, 2015 (in thousands): Three Months Ended June 30, 2015 Unrealized Loss on Derivative Instruments and Other Assets Foreign Currency Translation Adjustments Total Balances as of March 31, 2015 $ (6,921 ) $ (65,307 ) $ (72,228 ) Other comprehensive (loss) income before reclassifications (274 ) 2,100 1,826 Amounts reclassified from cumulative other comprehensive loss to net income 1,232 63,207 64,439 Net current period other comprehensive income 958 65,307 66,265 Balances as of June 30, 2015 $ (5,963 ) $ — $ (5,963 ) Six Months Ended June 30, 2015 Unrealized Loss on Derivative Instruments and Other Assets Foreign Currency Translation Adjustments Total Balances as of December 31, 2014 $ (4,299 ) $ (48,917 ) $ (53,216 ) Other comprehensive loss before reclassifications (1,043 ) (14,290 ) (15,333 ) Amounts reclassified from cumulative other comprehensive loss to net income (621 ) 63,207 62,586 Net current period other comprehensive (loss) income (1,664 ) 48,917 47,253 Balances as of June 30, 2015 $ (5,963 ) $ — $ (5,963 )
Schedule of Reclassifications Out of Cumulative Other Comprehensive Loss	The following tables present reclassifications out of cumulative other comprehensive loss for the three and six months ended June 30, 2015 (in thousands): Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income Details about Cumulative Other Comprehensive Loss Components Three Months Ended June 30, 2015 Six Months Ended June 30, 2015 Affected Line Items in the Statement of Operations Interest rate swap contracts $ 1,232 $ 2,459 Interest expense Foreign currency translation adjustment activity 63,207 63,207 (Loss) gain on sale of properties Realized gain on available for sale securities — (3,080 ) Interest and other income $ 64,439 $ 62,586

Income Taxes (Tables)

Income Taxes (Tables)	6 Months Ended
	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Taxes	Our provision for income taxes consists of the following (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Current: State $ 90 $ 227 $ 180 $ 261 Federal 525 — 525 — Foreign 2,450 681 2,404 1,202 3,065 908 3,109 1,463 Deferred: Foreign (150 ) — (755 ) — (150 ) — (755 ) — Income tax expense $ 2,915 $ 908 $ 2,354 $ 1,463

Derivative Instruments (Tables)

Derivative Instruments (Tables)	6 Months Ended
	Jun. 30, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Outstanding Interest Rate Derivatives Designated as Cash Flow Hedges of Interest Rate Risk	As of June 30, 2015 , we had the following outstanding interest rate derivatives that were designated as cash flow hedges of interest rate risk: Interest Rate Derivative Number of Instruments Notional Amount (in thousands) Interest rate swap 2 $170,573
Schedule of Derivative Financial Instruments at Fair Value	The table below presents the fair value of our derivative financial instruments as well as their classification on the condensed consolidated balance sheets as of June 30, 2015 and December 31, 2014 (amounts in thousands): Fair Value as of Interest Rate Derivative Designated as Hedging Instrument Balance Sheet Location June 30, December 31, Pay-fixed swaps Accounts payable and accrued expenses $ 5,963 $ 7,462
Schedule of Gain or Loss Recognized on Interest Rate Derivatives Designated as Cash Flow Hedges	The table below details the location in the financial statements of the gain or loss recognized on interest rate derivatives designated as cash flow hedges for the three and six months ended June 30, 2015 and 2014 (amounts in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Balance at beginning of period $ (6,921 ) $ (10,706 ) $ (7,462 ) $ (11,706 ) Amount of loss recognized in cumulative other comprehensive loss (274 ) (632 ) (960 ) (861 ) Amount of loss reclassified from cumulative other comprehensive loss into interest expense 1,232 1,259 2,459 2,488 Unrealized gain on derivative instruments 958 627 1,499 1,627 Balance at end of period $ (5,963 ) $ (10,079 ) $ (5,963 ) $ (10,079 )

Share-Based Compensation (Table

Share-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2015
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Summary of Assumptions and Fair Values for Restricted Stock Units Granted in the Period	The assumptions and fair values for the RSUs granted for the six months ended June 30, 2015 are included in the following table on a per share basis. 2015 Fair value of RSUs granted $ 38.55 Expected term (years) 4 Expected volatility — Expected dividend yield 1.88 % Risk-free rate 0.81 %

Fair Value of Assets and Liab34

Fair Value of Assets and Liabilities (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value	The table below presents certain of our assets and liabilities measured at fair value during 2015 , categorized by the level of inputs used in the valuation of each asset and liability (dollars in thousands): Fair Value at June 30, 2015 Using Quoted Prices in Active Markets for Identical Assets Significant Other Observable Inputs Significant Unobservable Inputs Description Total (Level 1) (Level 2) (Level 3) Recurring Fair Value Measurements: Effective portion of interest rate swap contracts $ (5,963 ) $ — $ (5,963 ) $ — Derivative liability (8,919 ) — — (8,919 )
Schedule of Valuation Techniques and Significant Unobservable Inputs used for Level 3 Fair Value Measurements	The valuation techniques and significant unobservable inputs used for our level 3 fair value measurement at June 30, 2015 were as follows: Description Fair Value at June 30, 2015 Primary Valuation Technique Unobservable Inputs Rate Derivative liability $ (8,919 ) Monte Carlo simulation Risk-free rate 0.30% Volatility 20.0%
Schedule of Fair Value and Carrying Value of Financial Instruments	At June 30, 2015 and December 31, 2014, the fair value of these additional financial instruments were not materially different from their carrying values, except as follows (in thousands): June 30, 2015 December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value Senior unsecured debt and mortgage notes payable, net $ 1,973,692 $ 2,033,171 $ 2,207,665 $ 2,263,535

Earnings Per Common Share (Tabl

Earnings Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2015
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share (amounts in thousands except per share amounts): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Numerator for earnings per common share - basic and diluted: Income from continuing operations $ 12,616 $ 6,688 $ 26,246 $ 23,413 Preferred distributions (6,981 ) (6,982 ) (13,962 ) (18,133 ) Excess fair value of consideration over carrying vale of preferred shares — (16,205 ) — (16,205 ) Income (loss) from continuing operations attributable to Equity Commonwealth common shareholders 5,635 (16,499 ) 12,284 (10,925 ) Discontinued operations — (1,303 ) — 2,420 Numerator for net income (loss) per share - basic and diluted $ 5,635 $ (17,802 ) $ 12,284 $ (8,505 ) Denominator for earnings per common share - basic and diluted: Weighted average number of common shares outstanding - basic 129,733 123,812 129,714 121,121 Weighted average number of common shares outstanding - diluted (1) 130,537 123,812 130,205 121,121 Earnings per share - basic and diluted: Income (loss) from continuing operations attributable to Equity Commonwealth common shareholders $ 0.04 $ (0.13 ) $ 0.09 $ (0.09 ) Discontinued operations — (0.01 ) — 0.02 Net income (loss) per share - basic and diluted $ 0.04 $ (0.14 ) $ 0.09 $ (0.07 ) Anti-dilutive securities: Effect of Series D preferred shares; 6 1/2% cumulative convertible (2) 2,363 4,721 2,363 6,017 (1) As of June 30, 2015 , we had granted RSUs to certain employees, officers, and the chairman of the Board of Trustees. The RSUs contain both service and market-based vesting components. None of the RSUs have vested. If the market-based vesting component was measured as of June 30, 2015 , 803 common shares would be issued to the RSU holders, and no shares would have been issued for the other periods presented. Using a weighted average basis, 804 and 491 common shares are reflected in diluted earnings per share for the three and six months ended June 30, 2015, respectively. (2) The Series D preferred shares are excluded from the diluted earnings per share calculation because including the Series D preferred shares would also require that the preferred distributions be added back to net income, resulting in anti-dilution during the periods presented.

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Schedule of Property Level Information by Operating Segment	Property level information by operating segment as of June 30, 2015 , and for the three and six months ended June 30, 2015 and 2014 , is as follows (in thousands): As of June 30, 2015 2014 Square feet: CBD properties 15,769 21,892 Suburban properties 13,616 21,028 Total properties(1) 29,385 42,920 (1) Square footage of properties owned as of the respective dates. Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Rental income: CBD properties $ 108,349 $ 106,094 $ 218,192 $ 216,333 Suburban properties 55,348 66,313 113,477 128,114 Total properties $ 163,697 $ 172,407 $ 331,669 $ 344,447 Tenant reimbursements and other income: CBD properties $ 27,683 $ 28,465 $ 57,380 $ 58,706 Suburban properties 12,314 14,322 27,700 29,301 Total properties $ 39,997 $ 42,787 $ 85,080 $ 88,007 NOI: CBD properties $ 75,566 $ 71,996 $ 149,513 $ 145,166 Suburban properties 38,442 50,497 79,679 92,856 Total properties $ 114,008 $ 122,493 $ 229,192 $ 238,022
Schedule of Reconciliation of NOI to Net Income	A reconciliation of NOI to net income for the three and six months ended June 30, 2015 and 2014 , is as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2015 2014 2015 2014 Rental income $ 163,697 $ 172,407 $ 331,669 $ 344,447 Tenant reimbursements and other income 39,997 42,787 85,080 88,007 Operating expenses (89,686 ) (92,701 ) (187,557 ) (194,432 ) NOI $ 114,008 $ 122,493 $ 229,192 $ 238,022 NOI $ 114,008 $ 122,493 $ 229,192 $ 238,022 Depreciation and amortization (53,637 ) (59,831 ) (116,336 ) (111,480 ) General and administrative (10,911 ) (24,097 ) (27,469 ) (48,945 ) Loss on asset impairment (15,258 ) (22,683 ) (17,162 ) (17,922 ) Acquisition related costs — — — (5 ) Operating income 34,202 15,882 68,225 59,670 Interest and other income 728 281 4,176 665 Interest expense (27,973 ) (37,899 ) (57,815 ) (75,834 ) Gain on early extinguishment of debt 10,426 — 9,998 — Loss on sale of equity investments — (33 ) — (33 ) Gain on issuance of shares by an equity investee — 16,911 — 17,020 Foreign currency exchange gain 856 — 856 — (Loss) gain on sale of properties (2,708 ) — 3,160 — Income (loss) from continuing operations before income taxes and equity in earnings of investees 15,531 (4,858 ) 28,600 1,488 Income tax expense (2,915 ) (908 ) (2,354 ) (1,463 ) Equity in earnings of investees — 12,454 — 23,388 Income from continuing operations 12,616 6,688 26,246 23,413 Income from discontinued operations — 4,114 — 8,125 Loss on asset impairment from discontinued operations — (2,072 ) — (2,360 ) Loss on early extinguishment of debt from discontinued operations — (3,345 ) — (3,345 ) Net income $ 12,616 $ 5,385 $ 26,246 $ 25,833

Board of Trustees - Narrative (

Board of Trustees - Narrative (Details) - trustee	Jun. 16, 2015	Jul. 31, 2014	May. 23, 2014	Feb. 18, 2014
Board of Trustees
Minimum holders of outstanding common shares consented to the proposal, reaching the required threshold (as a percent)				66.67%
Number of trustees elected		7	7
Total number of trustees	9	11

Real Estate Properties - Narrat

Real Estate Properties - Narrative (Details) $ in Thousands	Jun. 27, 2014USD ($)ft²propertybuilding	Mar. 31, 2014USD ($)ft²suburban_propertypropertybuilding	Jan. 31, 2013propertybuilding	Jun. 30, 2015USD ($)ft²propertybuilding	Jun. 30, 2014USD ($)ft²	Jun. 30, 2015USD ($)ft²propertybuilding	Jun. 30, 2014USD ($)ft²	Dec. 31, 2014property
Real Estate Properties [Line Items]
Real estate improvements | $						$ 27,800	$ 47,000
Number of real estate properties held for sale | property								0
Property square feet | ft²				29,385,000	42,920,000	29,385,000	42,920,000
Reversal of loss on asset impairment | $		$ 4,800
Number of properties sold or agreed to be sold | property			3
Number of buildings sold			18
Loss on asset impairment | $				$ 0	$ (2,072)	$ 0	$ (2,360)
Loss on early extinguishment of debt | $				$ 0	$ (3,345)	$ 0	$ (3,345)
Disposed of by Sale
Real Estate Properties [Line Items]
Property square feet | ft²				10,834,604		10,834,604
Number of properties sold or agreed to be sold | property				68
Number of buildings sold				83
CBD
Real Estate Properties [Line Items]
Number of real estate properties held for use | property		2
Number of buildings held for use		2
CBD | Disposed of by Sale
Real Estate Properties [Line Items]
Number of properties sold or agreed to be sold | property	1
Number of buildings sold	2
Suburban property
Real Estate Properties [Line Items]
Number of real estate properties held for use | suburban_property		29
Number of buildings held for use		65
Suburban property | Disposed of by Sale
Real Estate Properties [Line Items]
Number of properties sold or agreed to be sold | property	13
Number of buildings sold	41
CBD and suburban properties
Real Estate Properties [Line Items]
Property square feet | ft²		5,641,450
CBD and suburban properties | Disposed of by Sale
Real Estate Properties [Line Items]
Property square feet | ft²	2,784,098
Proceeds from sale of real estate | $	$ 215,900
Loss on asset impairment | $	2,400
Loss on early extinguishment of debt | $	$ 3,300
Illinois Center and 16th and Race Street
Real Estate Properties [Line Items]
Number of real estate properties held for sale | property				2		2
Number of building held for sale				3		3
Property square feet | ft²				2,698,787		2,698,787

Real Estate Properties - Summar

Real Estate Properties - Summary of Balance Sheet Information for all Properties Classified as Held for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Liabilities related to properties held for sale	$ 20,336	$ 0
Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Real estate properties	341,263
Acquired real estate leases	13,238
Other assets, net	6,280
Properties held for sale	360,781
Accounts payable and accrued expenses	12,387
Assumed real estate lease obligations	6,516
Rent collected in advance	113
Security deposits	1,320
Liabilities related to properties held for sale	$ 20,336

Real Estate Properties - Summ40

Real Estate Properties - Summary of Properties Sold (Details) $ in Thousands	Jun. 27, 2014propertybuilding	Jun. 30, 2015USD ($)ft²propertybuilding	May. 31, 2015USD ($)ft²propertybuilding	Apr. 30, 2015USD ($)ft²propertybuilding	Mar. 31, 2015USD ($)ft²propertybuilding	Jan. 31, 2015USD ($)ft²propertybuilding	Jan. 31, 2013propertybuilding	Jun. 30, 2015USD ($)ft²propertybuilding	Jun. 30, 2014USD ($)ft²	Jun. 30, 2015USD ($)ft²building	Jun. 30, 2014USD ($)ft²
Real Estate Properties [Line Items]
Number of Properties | property							3
Number of Buildings							18
Square Footage (in sqft) | ft²		29,385,000						29,385,000	42,920,000	29,385,000	42,920,000
Gain (Loss) on Sale | $								$ (2,708)	$ 0	$ 3,160	$ 0
333 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Buildings										3
1000 Vorhees Drive and 400 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Buildings										3
Disposed of by Sale
Real Estate Properties [Line Items]
Number of Properties | property								68
Number of Buildings								83
Square Footage (in sqft) | ft²		10,834,604						10,834,604		10,834,604
Gross Sales Price | $								$ 1,087,388
Gain (Loss) on Sale | $								$ 3,160
Disposed of by Sale | 333 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Buildings			2		1
Disposed of by Sale | 1000 Vorhees Drive and 400 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Buildings			2		1
Disposed of by Sale | Portfolio of Small Office and Industrial Assets
Real Estate Properties [Line Items]
Number of Properties | property			45
Number of Buildings			53
Square Footage (in sqft) | ft²			5,287,790
Gross Sales Price | $			$ 376,000
Gain (Loss) on Sale | $			$ (7,915)
Disposed of by Sale | AL, LA, NC, SC Office Portfolio
Real Estate Properties [Line Items]
Number of Properties | property		6
Number of Buildings		9
Square Footage (in sqft) | ft²		3,031,917						3,031,917		3,031,917
Gross Sales Price | $		$ 417,450
Gain (Loss) on Sale | $		$ 41,596
Disposed of by Sale | St. Louis Portfolio
Real Estate Properties [Line Items]
Number of Properties | property		2
Number of Buildings		2
Square Footage (in sqft) | ft²		165,098						165,098		165,098
Gross Sales Price | $		$ 14,300
Gain (Loss) on Sale | $		$ (2,338)
Disposed of by Sale | Australia Portfolio
Real Estate Properties [Line Items]
Number of Properties | property								11
Number of Buildings								11
Square Footage (in sqft) | ft²		1,758,525						1,758,525		1,758,525
Gross Sales Price | $								$ 232,955
Gain (Loss) on Sale | $								$ (47,804)
Suburban property | Disposed of by Sale
Real Estate Properties [Line Items]
Number of Properties | property	13
Number of Buildings	41
Suburban property | Disposed of by Sale | 11350 North Meridian Street
Real Estate Properties [Line Items]
Number of Properties | property						1
Number of Buildings						1
Square Footage (in sqft) | ft²						72,264
Gross Sales Price | $						$ 4,200
Gain (Loss) on Sale | $						$ 766
Suburban property | Disposed of by Sale | 333 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Properties | property					0
Number of Buildings					1
Square Footage (in sqft) | ft²					27,164
Gross Sales Price | $					$ 2,450
Gain (Loss) on Sale | $					$ 251
Suburban property | Disposed of by Sale | 1921 E. Alton Avenue
Real Estate Properties [Line Items]
Number of Properties | property					1
Number of Buildings					1
Square Footage (in sqft) | ft²					67,846
Gross Sales Price | $					$ 14,533
Gain (Loss) on Sale | $					$ 4,851
Suburban property | Disposed of by Sale | 46 Inverness Center Parkway
Real Estate Properties [Line Items]
Number of Properties | property				0
Number of Buildings				0
Square Footage (in sqft) | ft²				0
Gross Sales Price | $				$ 2,000
Gain (Loss) on Sale | $				$ 1,857
Suburban property | Disposed of by Sale | Sorrento Valley Business Park
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		4
Square Footage (in sqft) | ft²		105,003						105,003		105,003
Gross Sales Price | $		$ 23,500
Gain (Loss) on Sale | $		$ 11,896
Suburban property | Disposed of by Sale | 7450 Campus Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			77,411
Suburban property | Disposed of by Sale | 129 Worthington Ridge Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			227,500
Suburban property | Disposed of by Sale | 599 Research Parkway
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			48,249
Suburban property | Disposed of by Sale | 181 Marsh Hill Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			162,036
Suburban property | Disposed of by Sale | 101 Barnes Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			45,755
Suburban property | Disposed of by Sale | 15 Sterling Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			173,015
Suburban property | Disposed of by Sale | 35 Thorpe Avenue
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			79,862
Suburban property | Disposed of by Sale | 50 Barnes Industrial Road North
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			154,255
Suburban property | Disposed of by Sale | 5-9 Barnes Industrial Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			38,006
Suburban property | Disposed of by Sale | 860 North Main Street
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			31,165
Suburban property | Disposed of by Sale | One Barnes Industrial Road South
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			30,170
Suburban property | Disposed of by Sale | Village Lane
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			58,185
Suburban property | Disposed of by Sale | 100 Northfield Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			116,986
Suburban property | Disposed of by Sale | 905 Meridian Lake Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			74,652
Suburban property | Disposed of by Sale | 1717 Deerfield Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			141,186
Suburban property | Disposed of by Sale | 1955 West Field Court
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			59,130
Suburban property | Disposed of by Sale | 5015 S. Water Circle
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			113,524
Suburban property | Disposed of by Sale | Adams Place
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			230,259
Suburban property | Disposed of by Sale | Cabot Business Park
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			252,755
Suburban property | Disposed of by Sale | 2300 Crown Colony Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			45,974
Suburban property | Disposed of by Sale | Myles Standish Industrial Park
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			74,800
Suburban property | Disposed of by Sale | 340 Thompson Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			25,000
Suburban property | Disposed of by Sale | 6710 Oxon Hill
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			118,336
Suburban property | Disposed of by Sale | 8800 Queen Avenue South
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			280,822
Suburban property | Disposed of by Sale | 9800 Sherlard Parkway
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			46,765
Suburban property | Disposed of by Sale | Rosedale Corporate Plaza
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			3
Square Footage (in sqft) | ft²			149,116
Suburban property | Disposed of by Sale | 1000 Shelard Parkway
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			62,499
Suburban property | Disposed of by Sale | 1900 Meyer Drury Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			65,225
Suburban property | Disposed of by Sale | 131-165 West Ninth Street
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			75,517
Suburban property | Disposed of by Sale | 7-9 Vreeland Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			155,891
Suburban property | Disposed of by Sale | 5 Paragon Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			119,089
Suburban property | Disposed of by Sale | 1000 Vorhees Drive and 400 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			125,415
Suburban property | Disposed of by Sale | 1601 Veterans Highway
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			63,608
Suburban property | Disposed of by Sale | Two Corporate Center Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			291,230
Suburban property | Disposed of by Sale | 11311 Cornell Center Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			93,413
Suburban property | Disposed of by Sale | 5300 Kings Island Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			159,421
Suburban property | Disposed of by Sale | 3 Crown Point Court
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			73,987
Suburban property | Disposed of by Sale | 515 Pennsylvania Avenue
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			82,000
Suburban property | Disposed of by Sale | 443 Gulph Road
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			21,000
Suburban property | Disposed of by Sale | 4350 Northern Pike
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			503,885
Suburban property | Disposed of by Sale | Thunderbolt Place
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			2
Square Footage (in sqft) | ft²			100,505
Suburban property | Disposed of by Sale | 6160 Kempsville Circle
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			129,565
Suburban property | Disposed of by Sale | 448 Viking Drive
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			75,374
Suburban property | Disposed of by Sale | Inverness Center
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		4
Square Footage (in sqft) | ft²		475,951						475,951		475,951
Suburban property | Disposed of by Sale | 12655 Olive Boulevard
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		98,588						98,588		98,588
Suburban property | Disposed of by Sale | 1285 Fern Ridge Parkway
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		66,510						66,510		66,510
Suburban property | Disposed of by Sale | 310-314 Invermay Road
Real Estate Properties [Line Items]
Number of Properties | property				1
Number of Buildings				1
Square Footage (in sqft) | ft²				47,480
Suburban property | Disposed of by Sale | 253-293 George Town Road
Real Estate Properties [Line Items]
Number of Properties | property				1
Number of Buildings				1
Square Footage (in sqft) | ft²				143,914
Suburban property | Disposed of by Sale | 7 Modal Crescent
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		164,160						164,160		164,160
Suburban property | Disposed of by Sale | 71-93 Whiteside Road
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		303,488						303,488		303,488
Suburban property | Disposed of by Sale | 9-13 Titanium Court
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		69,664						69,664		69,664
Suburban property | Disposed of by Sale | 16 Rodborough Road
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		90,525						90,525		90,525
Suburban property | Disposed of by Sale | 22 Rodborough Road
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		43,427						43,427		43,427
Suburban property | Disposed of by Sale | 127-161 Cherry Lane
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		278,570						278,570		278,570
Suburban property | Disposed of by Sale | 44-46 Mandarin Street
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		226,718						226,718		226,718
Suburban property | Disposed of by Sale | 19 Leadership Way
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		76,714						76,714		76,714
CBD | Disposed of by Sale
Real Estate Properties [Line Items]
Number of Properties | property	1
Number of Buildings	2
CBD | Disposed of by Sale | 100 South Charles Street
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			159,616
CBD | Disposed of by Sale | 525 Park Street
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			75,636
CBD | Disposed of by Sale | 2501 20th Place South
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		125,722						125,722		125,722
CBD | Disposed of by Sale | 420 20th Street North
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		514,893						514,893		514,893
CBD | Disposed of by Sale | 701 Poydras Street
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		1,256,971						1,256,971		1,256,971
CBD | Disposed of by Sale | 300 North Greene Street
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		324,305						324,305		324,305
CBD | Disposed of by Sale | 1320 Main Street
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		334,075						334,075		334,075
CBD | Disposed of by Sale | 310-320 Pitt Street
Real Estate Properties [Line Items]
Number of Properties | property		1
Number of Buildings		1
Square Footage (in sqft) | ft²		313,865						313,865		313,865
CBD | Foreclosure | 225 Water Street
Real Estate Properties [Line Items]
Number of Properties | property			1
Number of Buildings			1
Square Footage (in sqft) | ft²			318,997
Gross Sales Price | $			$ 0
Gain (Loss) on Sale | $			$ 0

Real Estate Properties - Summ41

Real Estate Properties - Summary of Properties Sold (Footnote) (Details) $ in Thousands	1 Months Ended			3 Months Ended		6 Months Ended
	May. 31, 2015building	Mar. 31, 2015building	Jan. 31, 2013building	Jun. 30, 2015USD ($)building	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)building	Jun. 30, 2014USD ($)
Real Estate Properties [Line Items]
Number of buildings sold			18
Gain on early extinguishment of debt | $				$ 10,426	$ 0	$ 9,998	$ 0
Amounts reclassified from cumulative other comprehensive loss to net income | $				64,439		62,586
Foreign Currency Translation Adjustments
Real Estate Properties [Line Items]
Amounts reclassified from cumulative other comprehensive loss to net income | $				$ 63,207		$ 63,207
Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold				83
333 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of buildings sold						3
333 Laurel Oak Drive | Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold	2	1
1000 Vorhees Drive and 400 Laurel Oak Drive
Real Estate Properties [Line Items]
Number of buildings sold						3
1000 Vorhees Drive and 400 Laurel Oak Drive | Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold	2	1
225 Water Street in Jacksonville, Florida | Mortgage notes
Real Estate Properties [Line Items]
Principal balance | $				$ 40,100		$ 40,100
Gain on early extinguishment of debt | $				$ 17,300		17,300
Australia Portfolio | Foreign Currency Translation Adjustments
Real Estate Properties [Line Items]
Amounts reclassified from cumulative other comprehensive loss to net income | $						$ (63,200)
Australia Portfolio | Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold				11

Real Estate Properties - Summ42

Real Estate Properties - Summary of Income Statement Information for Properties Disposed of (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statements of Operations:
Rental income	$ 163,697	$ 172,407	$ 331,669	$ 344,447
Tenant reimbursements and other income	39,997	42,787	85,080	88,007
Total revenues	203,694	215,194	416,749	432,454
Operating expenses	89,686	92,701	187,557	194,432
General and administrative	10,911	24,097	27,469	48,945
Total expenses	169,492	199,312	348,524	372,784
Operating income	34,202	15,882	68,225	59,670
Interest expense	(27,973)	(37,899)	(57,815)	(75,834)
Income from discontinued operations	$ 0	4,114	$ 0	8,125
Discontinued operations, properties sold
Statements of Operations:
Rental income		6,962		14,236
Tenant reimbursements and other income		801		1,323
Total revenues		7,763		15,559
Operating expenses		3,375		6,854
General and administrative		0		3
Total expenses		3,375		6,857
Operating income		4,388		8,702
Interest expense		(274)		(577)
Income from discontinued operations		$ 4,114		$ 8,125

Investment in Direct Financin43

Investment in Direct Financing Lease - Narrative (Details) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Percentage of term exceeding useful life of one office tower	75.00%
Carrying amount of net investment in direct financing lease	$ 8,700,000	$ 12,500,000
Allowance for losses related to our direct financing lease	$ 0	$ 0

Equity Investments - Narrative

Equity Investments - Narrative (Details) $ in Thousands	Jul. 09, 2014shares	May. 09, 2014USD ($)companyshares	May. 09, 2014USD ($)company	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	May. 09, 2014USD ($)company	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)
Equity Investments
Equity in earnings (loss) of investees				$ 0	$ 12,454		$ 0	$ 23,388
Distributions of earnings from investees							$ 0	20,680
AIC
Equity Investments
Equity investments, common shares sold (in shares) | shares		20,000
Equity method investments, ownership percentage		0.00%	0.00%			0.00%
Equity in earnings (loss) of investees			$ 40			$ (100)
Amount invested in equity investee		$ 5,800	$ 5,800			$ 5,800
Number of other companies which are shareholders of related party | company		5	5			5
Equity investments, proceeds from sale		$ 5,800
SIR
Equity Investments
Equity investments, common shares sold (in shares) | shares	22,000,000
Equity method investments, ownership percentage	0.00%
Equity in earnings (loss) of investees					12,400			23,400
Distributions of earnings from investees					$ 10,600			$ 20,700

Equity Investments - Summary of

Equity Investments - Summary of Unaudited Income Statement Information of Equity Method Investee (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Statements:
Rental income	$ 163,697	$ 172,407	$ 331,669	$ 344,447
Tenant reimbursements and other income	39,997	42,787	85,080	88,007
Total revenues	203,694	215,194	416,749	432,454
Operating expenses	89,686	92,701	187,557	194,432
General and administrative	10,911	24,097	27,469	48,945
Total expenses	169,492	199,312	348,524	372,784
Operating income	34,202	15,882	68,225	59,670
Interest expense	(27,973)	(37,899)	(57,815)	(75,834)
Gain on early extinguishment of debt	10,426	0	9,998	0
Income before income tax expense and equity in earnings of an investee	15,531	(4,858)	28,600	1,488
Income tax expense	(2,915)	(908)	(2,354)	(1,463)
Equity in earnings of investees	0	12,454	0	23,388
Net income	$ 12,616	$ 5,385	$ 26,246	$ 25,833
Weighted average common shares outstanding (in shares)	129,733	123,812	129,714	121,121
SIR
Income Statements:
Rental income		$ 48,465		$ 93,528
Tenant reimbursements and other income		8,092		16,057
Total revenues		56,557		109,585
Operating expenses		9,985		19,964
Depreciation and amortization		10,495		19,789
Acquisition related costs		136		374
General and administrative		2,198		7,374
Total expenses		22,814		47,501
Operating income		33,743		62,084
Interest expense		(3,634)		(6,992)
Gain on early extinguishment of debt		0		243
Income before income tax expense and equity in earnings of an investee		30,109		55,335
Income tax expense		(19)		(90)
Equity in earnings of investees		118		21
Net income		$ 30,208		$ 55,266
Weighted average common shares outstanding (in shares)		54,178		52,021
Net income per common share (in dollars per share)		$ 0.56		$ 1.06

Real Estate Mortgages Receiva46

Real Estate Mortgages Receivable - Narrative (Details)	1 Months Ended
	Jan. 31, 2013USD ($)propertybuilding	Apr. 30, 2012USD ($)	Jun. 30, 2015USD ($)	Dec. 31, 2014USD ($)
Real Estate Mortgages Receivable
Total real estate mortgage receivable included in other assets, carrying value			$ 8,100,000	$ 8,100,000
Mortgage financing related to sale of suburban property	$ 7,700,000	$ 400,000
Interest rate on real estate mortgage receivable	6.00%	6.00%
Number of properties sold or agreed to be sold | property	3
Number of Buildings | building	18
Allowance for mortgage receivables			$ 0	$ 0

Indebtedness - Narrative (Detai

Indebtedness - Narrative (Details)	Jun. 05, 2015USD ($)	Jun. 03, 2015USD ($)	May. 01, 2015USD ($)	Jan. 29, 2015USD ($)option	Jan. 28, 2015USD ($)	Jun. 30, 2015USD ($)propertybuilding	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)propertybuilding	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)propertybuilding	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt						$ 10,426,000	$ 0	$ 9,998,000	$ 0
Real estate properties, net						3,378,166,000		3,378,166,000		$ 3,378,166,000	$ 4,697,998,000
Mortgage notes payable, net						513,561,000		$ 513,561,000		513,561,000	$ 609,249,000
Revolving credit facility
Debt Instrument [Line Items]
Interest rate payable percentage								1.44%
Amount outstanding						0		$ 0		0
Revolving credit facility | Minimum
Debt Instrument [Line Items]
Commitment fee percentage				0.125%
Revolving credit facility | Maximum
Debt Instrument [Line Items]
Commitment fee percentage				0.30%
Revolving credit facility | LIBOR
Debt Instrument [Line Items]
Basis points on variable rate								1.25%
Revolving credit facility | LIBOR | Minimum
Debt Instrument [Line Items]
Basis points on variable rate				0.875%
Revolving credit facility | LIBOR | Maximum
Debt Instrument [Line Items]
Basis points on variable rate				1.55%
Revolving credit facility | Base rate | Minimum
Debt Instrument [Line Items]
Basis points on variable rate				0.00%
Revolving credit facility | Base rate | Maximum
Debt Instrument [Line Items]
Basis points on variable rate				0.55%
Unsecured term loan, due December 2016
Debt Instrument [Line Items]
Basis points on variable rate											1.85%
Outstanding indebtedness					$ 400,000,000
Unsecured revolving credit facility | Revolving credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 750,000,000	$ 750,000,000
Basis points on variable rate											1.50%
Commitment fee percentage					0.35%
Gain (loss) on early extinguishment of debt								$ (400,000)
Debt instrument, number of extension options | option				2
Debt instrument, extension option term				6 months
Debt instrument, extension option fee, percent				0.075%
Amount available for borrowing						750,000,000		750,000,000		750,000,000
Unsecured revolving credit facility | Letter of Credit [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 100,000,000
Loan facility, 5-year term
Debt Instrument [Line Items]
Term loan amount outstanding				$ 200,000,000		200,000,000		$ 200,000,000		200,000,000
Interest accrual rate								1.59%
Loan facility, 5-year term | LIBOR
Debt Instrument [Line Items]
Basis points on variable rate								1.40%
Loan facility, 5-year term | LIBOR | Minimum
Debt Instrument [Line Items]
Basis points on variable rate				0.90%
Loan facility, 5-year term | LIBOR | Maximum
Debt Instrument [Line Items]
Basis points on variable rate				1.80%
Loan facility, 5-year term | Revolving credit facility
Debt Instrument [Line Items]
Debt instrument, term				5 years
Loan facility, 7-year term
Debt Instrument [Line Items]
Term loan amount outstanding				$ 200,000,000		$ 200,000,000		$ 200,000,000		$ 200,000,000
Interest accrual rate								1.99%
Loan facility, 7-year term | LIBOR
Debt Instrument [Line Items]
Basis points on variable rate								1.80%
Loan facility, 7-year term | LIBOR | Minimum
Debt Instrument [Line Items]
Basis points on variable rate				1.40%
Loan facility, 7-year term | LIBOR | Maximum
Debt Instrument [Line Items]
Basis points on variable rate				2.35%
Loan facility, 7-year term | Revolving credit facility
Debt Instrument [Line Items]
Debt instrument, term				7 years
Revolving credit facility and term loans
Debt Instrument [Line Items]
Additional increases in maximum amount of borrowings available				$ 1,150,000,000
5.75% unsecured senior notes due 2015
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt			$ (100,000)
Amount of debt, redeemed, defeased, or prepaid			$ 138,800,000
Interest rate stated percentage			5.75%
Mortgage notes
Debt Instrument [Line Items]
Number of real estate properties secured by mortgage | property						7		7		7
Number of buildings secured by mortgage | building						11		11		11
Real estate properties, net						$ 605,500,000		$ 605,500,000		$ 605,500,000
Mortgage notes payable, net						513,600,000		513,600,000		513,600,000
Mortgage notes | 225 Water Street in Jacksonville, Florida
Debt Instrument [Line Items]
Outstanding indebtedness						40,100,000		40,100,000		$ 40,100,000
Gain (loss) on early extinguishment of debt						17,300,000		17,300,000
Interest accrual rate										10.03%
Default interest										4.00%
Mortgage notes | 1320 Main Street
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt						(6,200,000)		(6,200,000)
Amount of debt, redeemed, defeased, or prepaid		$ 38,700,000
7.36% Mortgage Debt | 2501 20th Place South
Debt Instrument [Line Items]
Gain (loss) on early extinguishment of debt						$ (600,000)		$ (600,000)
Amount of debt, redeemed, defeased, or prepaid	$ 10,000,000
Interest rate stated percentage	7.36%

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 25, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Class of Stock [Line Items]
Distribution for the excess of the market value of common shares issued above carrying value of series D preferred shares redeemed		$ 0	$ (16,205)	$ 0	$ (16,205)
Common Shares
Class of Stock [Line Items]
Common shares issued to holders of preferred shares (in shares)				144		10,412,499
Common shares from conversion of preferred shares (in shares)		2,363,103		2,363,103
Common Shares | Fundamental change conversion right
Class of Stock [Line Items]
Preferred shares converted into common shares (in shares)	10,411,779
Series D
Class of Stock [Line Items]
Liquidation preference (in dollars per share)	$ 25
Percentage of average closing market price of the entity's common stock based on which ratio for conversion of preferred shares into common shares is determined	98.00%
Number of consecutive trading days for calculating the average closing sale price of common shares	5 days
Preferred shares converted into common shares (in shares)				301		10,264,503
Common shares from conversion of preferred shares (in shares)		4,915,196		4,915,196
Series D | Fundamental change conversion right
Class of Stock [Line Items]
Preferred shares converted into common shares (in shares)	10,263,003
Distribution for the excess of the market value of common shares issued above carrying value of series D preferred shares redeemed	$ (16,200)

Shareholders' Equity - Schedule

Shareholders' Equity - Schedule of Declared Distributions (Details) - $ / shares	Jul. 09, 2015	Apr. 08, 2015	Jan. 16, 2015
Series D
Class of Stock [Line Items]
Dividend declared (in dollars per share)		$ 0.40625	$ 0.40625
Series D | Subsequent event
Class of Stock [Line Items]
Dividend declared (in dollars per share)	$ 0.40625
Series E
Class of Stock [Line Items]
Dividend declared (in dollars per share)		$ 0.453125	$ 0.453125
Series E | Subsequent event
Class of Stock [Line Items]
Dividend declared (in dollars per share)	$ 0.453125

Cumulative Other Comprehensiv50

Cumulative Other Comprehensive Loss - Schedule of Amounts Recognized in Cumulative Other Comprehensive Loss (Details) - Jun. 30, 2015 - USD ($) $ in Thousands	Total	Total
Amounts recognized in cumulative other comprehensive income (Loss) by component
Balance at beginning of period	$ (72,228)	$ (53,216)
Other comprehensive (loss) income before reclassifications	1,826	(15,333)
Amounts reclassified from cumulative other comprehensive loss to net income	64,439	62,586
Net current period other comprehensive income	66,265	47,253
Balance at end of period	(5,963)	(5,963)
Unrealized Loss on Derivative Instruments and Other Assets
Amounts recognized in cumulative other comprehensive income (Loss) by component
Balance at beginning of period	(6,921)	(4,299)
Other comprehensive (loss) income before reclassifications	(274)	(1,043)
Amounts reclassified from cumulative other comprehensive loss to net income	1,232	(621)
Net current period other comprehensive income	958	(1,664)
Balance at end of period	(5,963)	(5,963)
Foreign Currency Translation Adjustments
Amounts recognized in cumulative other comprehensive income (Loss) by component
Balance at beginning of period	(65,307)	(48,917)
Other comprehensive (loss) income before reclassifications	2,100	(14,290)
Amounts reclassified from cumulative other comprehensive loss to net income	63,207	63,207
Net current period other comprehensive income	65,307	48,917
Balance at end of period	$ 0	$ 0

Cumulative Other Comprehensiv51

Cumulative Other Comprehensive Loss - Schedule of Reclassifications Out of Cumulative Other Comprehensive Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reclassifications out of cumulative other comprehensive income (Loss)
Interest rate swap contracts	$ 27,973	$ 37,899	$ 57,815	$ 75,834
Gain (Loss) on Sale	(2,708)	0	3,160	0
Interest and Other Income	(728)	$ (281)	(4,176)	$ (665)
Total amounts reclassified	(64,439)		(62,586)
Foreign currency translation adjustment activity
Reclassifications out of cumulative other comprehensive income (Loss)
Total amounts reclassified	(63,207)		(63,207)
Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income
Reclassifications out of cumulative other comprehensive income (Loss)
Total amounts reclassified	64,439		62,586
Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income | Foreign currency translation adjustment activity
Reclassifications out of cumulative other comprehensive income (Loss)
Gain (Loss) on Sale	63,207		63,207
Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income | Realized gain on available for sale securities
Reclassifications out of cumulative other comprehensive income (Loss)
Interest and Other Income	0		(3,080)
Amounts Reclassified from Cumulative Other Comprehensive Loss to Net Income | Interest rate swap contracts
Reclassifications out of cumulative other comprehensive income (Loss)
Interest rate swap contracts	$ 1,232		$ 2,459

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Current:
State	$ 90	$ 227	$ 180	$ 261
Federal	525	0	525	0
Foreign	2,450	681	2,404	1,202
Current income tax expense (benefit)	3,065	908	3,109	1,463
Deferred:
Foreign	(150)	0	(755)	0
Deferred income tax expense (benefit)	(150)	0	(755)	0
Income tax expense	$ 2,915	$ 908	$ 2,354	$ 1,463

Derivative Instruments - Narrat

Derivative Instruments - Narrative (Details) - Jun. 30, 2015 - USD ($)	Total
Derivative [Line Items]
Aggregate termination value	$ 6,500,000
Cash flow hedging
Derivative [Line Items]
Estimated gain (loss) reclassification from OCI to income	4,500,000
Interest rate swap
Derivative [Line Items]
Amount of hedged item	$ 170,600,000
Derivative, variable interest rate	LIBOR
Fair value of derivatives in a net liability position	$ 6,500,000

Derivative Instruments - Schedu

Derivative Instruments - Schedule of Outstanding Interest Rate Derivatives Designated as Cash Flow Hedges of Interest Rate Risk (Details) - Jun. 30, 2015 - Interest rate swap $ in Thousands	USD ($)financial_instrument
Derivative [Line Items]
Number of Instruments	2
Notional Amount | $	$ 170,573

Derivative Instruments - Sche55

Derivative Instruments - Schedule of Derivative Financial Instruments at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Interest rate swap | Designated as hedging instrument | Accounts payable and accrued expenses
Derivatives, Fair Value [Line Items]
Pay-fixed swaps	$ 5,963	$ 7,462

Derivative Instruments - Sche56

Derivative Instruments - Schedule of Gain or Loss Recognized on Interest Rate Derivatives Designated as Cash Flow Hedges (Details) - Cash flow hedging - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Interest Rate Cash Flow Hedges [Roll Forward]
Balance at beginning of period	$ (6,921)	$ (10,706)	$ (7,462)	$ (11,706)
Amount of loss recognized in cumulative other comprehensive loss	(274)	(632)	(960)	(861)
Amount of loss reclassified from cumulative other comprehensive loss into interest expense	1,232	1,259	2,459	2,488
Unrealized gain on derivative instruments	958	627	1,499	1,627
Balance at end of period	$ (5,963)	$ (10,079)	$ (5,963)	$ (10,079)

Share-Based Compensation - Narr

Share-Based Compensation - Narrative (Details) $ / shares in Units, $ in Millions	Jun. 16, 2015USD ($)trustee$ / sharesshares	Jan. 28, 2015tranche$ / sharesshares	Mar. 25, 2014shares	Jun. 30, 2015USD ($)$ / sharesshares	Jun. 30, 2015USD ($)$ / sharesshares	Jun. 30, 2014USD ($)	Jul. 31, 2014trustee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of independent trustees | trustee	9						11
Officers and Employees | Employee Stock | RMR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense | $						$ 3.4
Officers and Employees | Employee Stock | Common Stock | RMR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares issued (in shares)			130,914
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation amount | $	$ 0.1
Number of equity awards granted (in shares)	34,587	126,319
Price per share (in dollars per share) | $ / shares	$ 26.02
Vesting period	1 year	4 years
Number of shares forfeited (in shares)				8,115	8,115
Weighted average share price for forfeited shares (in dollars per share) | $ / shares				$ 26.64	$ 26.64
Granted shares value (in dollars per share) | $ / shares		$ 26.58
Estimated future compensation expense for unvested shares | $				$ 17.5	$ 17.5
Weighted average period over which compensation expense will be recorded					3 years 3 months 18 days
Restricted shares | Independent Trustee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity awards granted (in shares)	3,843
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of incentive plan after effective date					4 years
Number of equity awards granted (in shares)		256,467
Number of shares forfeited (in shares)				16,475	16,475
Weighted average share price for forfeited shares (in dollars per share) | $ / shares				$ 20.50	$ 20.50
Granted shares value (in dollars per share) | $ / shares					$ 38.55
Estimated future compensation expense for unvested shares | $				$ 25	$ 25
Weighted average period over which compensation expense will be recorded					2 years 10 months 24 days
Number of tranches | tranche		2
Restricted stock units | Vesting on January 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent		50.00%
Restricted stock units | Vesting on January 28, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percent		50.00%
Maximum | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of RSU grants grant recipients may earn		100.00%
Minimum | Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of RSU grants grant recipients may earn		0.00%
2015 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of incentive plan after effective date	10 years
2015 Incentive Plan [Member] | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for issuance (in shares)	3,250,000
Share award plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares available for issuance (in shares)				3,215,413	3,215,413
Share award plan | General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense | $				$ 4.1	$ 8.1

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Assumptions and Fair Values for Restricted Stock Units Granted in the Period (Details) - 6 months ended Jun. 30, 2015 - Restricted stock units - $ / shares	Total
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Fair value of RSUs granted (in dollars per share)	$ 38.55
Expected term (years)	4 years
Expected volatility	0.00%
Expected dividend yield	1.88%
Risk-free rate	0.81%

Fair Value of Assets and Liab59

Fair Value of Assets and Liabilities - Schedule of Assets and Liabilities Measure at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Recurring Fair Value Measurements:
Derivative liability		$ (9,300)	$ (6,700)
Recurring
Recurring Fair Value Measurements:
Effective portion of interest rate swap contracts	$ (5,963)
Derivative liability	(8,919)
Recurring | Level 1
Recurring Fair Value Measurements:
Effective portion of interest rate swap contracts	0
Derivative liability	0
Recurring | Level 2
Recurring Fair Value Measurements:
Effective portion of interest rate swap contracts	(5,963)
Derivative liability	0
Recurring | Level 3
Recurring Fair Value Measurements:
Effective portion of interest rate swap contracts	0
Derivative liability	$ (8,919)

Fair Value of Assets and Liab60

Fair Value of Assets and Liabilities - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Jul. 31, 2015USD ($)$ / shares	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)Tenant	Aug. 06, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jul. 31, 2014USD ($)$ / shares	Jun. 30, 2014USD ($)	Dec. 31, 2013USD ($)
Fair value of assets and liabilities
Fair value of derivative liability					$ (9,300)	$ (6,700)
Number of tenants responsible for more than 3% of total annualized rents | Tenant			0
Cash and cash equivalents			$ 1,286,902			$ 364,516		$ 420,664	$ 217,032
Subsequent event | Australia Subsidiary
Fair value of assets and liabilities
Cash and cash equivalents				$ 7,000
Subsequent event | Forecast
Fair value of assets and liabilities
Foreign currency exchange loss		$ 9,500
Australia Subsidiary | Subsequent event
Fair value of assets and liabilities
Transfer of US Dollars from Australian Subsidiary	$ 218,000
Total rents | Credit concentration
Fair value of assets and liabilities
Concentration risk			3.00%
Related/Corvex
Fair value of assets and liabilities
Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period after the date on which the reimbursement is approved by shareholders							$ 8,400
Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period between the first and second anniversaries of the date on which the reimbursement is approved by shareholders							$ 8,400
Minimum
Fair value of assets and liabilities
Price per common share during one year period after date (in dollars per share) | $ / shares							$ 26
Price per common share during first and second year after date (in dollars per share) | $ / shares							$ 26
Minimum | Subsequent event
Fair value of assets and liabilities
Price per common share during one year period after date (in dollars per share) | $ / shares	$ 26

Fair Value of Assets and Liab61

Fair Value of Assets and Liabilities - Schedule of Valuation Techniques and Significant Unobservable Inputs Used for Level 3 Fair Value Measurements (Details) - Jun. 30, 2015 - Derivative liability - Level 3 - USD ($) $ in Thousands	Total
Fair Value of Assets and Liabilities
Derivative liability	$ (8,919)
Risk-free rate	0.30%
Volatility	20.00%

Fair Value of Assets and Liab62

Fair Value of Assets and Liabilities - Schedule of Fair Value and Carrying Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Carrying Amount
Fair value of financial instruments
Senior unsecured debt and mortgage notes payable, net	$ 1,973,692	$ 2,207,665
Fair Value
Fair value of financial instruments
Senior unsecured debt and mortgage notes payable, net	$ 2,033,171	$ 2,263,535

Earnings Per Common Share - Sch

Earnings Per Common Share - Schedule of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Numerator for earnings per common share - basic and diluted:
Income from continuing operations	$ 12,616	$ 6,688	$ 26,246	$ 23,413
Preferred distributions	(6,981)	(6,982)	(13,962)	(18,133)
Excess fair value of consideration over carrying value of preferred shares	0	(16,205)	0	(16,205)
Income (loss) from continuing operations attributable to Equity Commonwealth common shareholders	5,635	(16,499)	12,284	(10,925)
Discontinued operations	0	(1,303)	0	2,420
Numerator for net income (loss) per share - basic and diluted	$ 5,635	$ (17,802)	$ 12,284	$ (8,505)
Denominator for earnings per common share - basic and diluted:
Weighted average common shares outstanding — basic (in shares)	129,733	123,812	129,714	121,121
Weighted average common shares outstanding — diluted (in shares)	130,537	123,812	130,205	121,121
Earnings per share - basic and diluted:
Income (loss) from continuing operations (in dollars per share)	$ 0.04	$ (0.13)	$ 0.09	$ (0.09)
Discontinued operations (in dollars per share)	0	(0.01)	0	0.02
Net income (loss) per share - basic and diluted (in dollars per share)	$ 0.04	$ (0.14)	$ 0.09	$ (0.07)
Effect of Series D preferred shares; 6 1/2% cumulative convertible
Anti-dilutive securities:
Anti-dilutive securities (in shares)	2,363	4,721	2,363	6,017

Earnings Per Common Share - S64

Earnings Per Common Share - Schedule of Computation of Basic and Diluted Earnings Per Share (Footnote) (Details) - Restricted stock units - shares	3 Months Ended	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
RSUs vested (in shares)		0
Common shares issued (in shares)	803,000	803,000	0
Weighted average common shares outstanding — diluted (in shares)	804,000	491,000

Segment Information - Narrative

Segment Information - Narrative (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2015USD ($)suburban_propertypropertybuildingsegment	Dec. 31, 2014USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	2
Real estate properties, net	$ 3,378,166	$ 4,697,998
CBD Properties
Segment Reporting Information [Line Items]
Number of real estate properties | property	29
Number of buildings | building	41
Real estate properties, net	$ 2,182,700
Suburban Properties
Segment Reporting Information [Line Items]
Number of real estate properties | suburban_property	57
Number of buildings | building	135
Real estate properties, net	$ 1,195,500
Minimum
Segment Reporting Information [Line Items]
Percentage of CBD and suburban properties that are office properties	90.00%

Segment Information - Schedule

Segment Information - Schedule of Property Level Information by Operating Segment (Details) ft² in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015USD ($)ft²	Jun. 30, 2014USD ($)ft²	Jun. 30, 2015USD ($)ft²	Jun. 30, 2014USD ($)ft²
Segment Reporting Information [Line Items]
Square Footage (in sqft) | ft²	29,385	42,920	29,385	42,920
Rental income	$ 163,697	$ 172,407	$ 331,669	$ 344,447
Tenant reimbursements and other income	39,997	42,787	85,080	88,007
NOI	$ 114,008	$ 122,493	$ 229,192	$ 238,022
CBD Properties
Segment Reporting Information [Line Items]
Square Footage (in sqft) | ft²	15,769	21,892	15,769	21,892
Rental income	$ 108,349	$ 106,094	$ 218,192	$ 216,333
Tenant reimbursements and other income	27,683	28,465	57,380	58,706
NOI	$ 75,566	$ 71,996	$ 149,513	$ 145,166
Suburban Properties
Segment Reporting Information [Line Items]
Square Footage (in sqft) | ft²	13,616	21,028	13,616	21,028
Rental income	$ 55,348	$ 66,313	$ 113,477	$ 128,114
Tenant reimbursements and other income	12,314	14,322	27,700	29,301
NOI	$ 38,442	$ 50,497	$ 79,679	$ 92,856

Segment Information - Schedul67

Segment Information - Schedule of Reconciliation of NOI to Net Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting [Abstract]
Rental income	$ 163,697	$ 172,407	$ 331,669	$ 344,447
Tenant reimbursements and other income	39,997	42,787	85,080	88,007
Operating expenses	(89,686)	(92,701)	(187,557)	(194,432)
NOI	114,008	122,493	229,192	238,022
Depreciation and amortization	(53,637)	(59,831)	(116,336)	(111,480)
General and administrative	(10,911)	(24,097)	(27,469)	(48,945)
Loss on asset impairment	(15,258)	(22,683)	(17,162)	(17,922)
Acquisition related costs	0	0	0	(5)
Operating income	34,202	15,882	68,225	59,670
Interest and other income	728	281	4,176	665
Interest expense	(27,973)	(37,899)	(57,815)	(75,834)
Gain on early extinguishment of debt	10,426	0	9,998	0
Loss on sale of equity investment	0	(33)	0	(33)
Gain on issuance of shares by an equity investee	0	16,911	0	17,020
Foreign currency exchange gain	856	0	856	0
(Loss) gain on sale of properties	(2,708)	0	3,160	0
Income (loss) from continuing operations before income taxes and equity in earnings of investees	15,531	(4,858)	28,600	1,488
Income tax expense	(2,915)	(908)	(2,354)	(1,463)
Equity in earnings of investees	0	12,454	0	23,388
Income from continuing operations	12,616	6,688	26,246	23,413
Income from discontinued operations	0	4,114	0	8,125
Loss on asset impairment from discontinued operations	0	(2,072)	0	(2,360)
Loss on early extinguishment of debt from discontinued operations	0	(3,345)	0	(3,345)
Net income	$ 12,616	$ 5,385	$ 26,246	$ 25,833

Related Person Transactions - N

Related Person Transactions - Narrative (Details)

Aug. 05, 2015USD ($)

Jul. 20, 2015USD ($)option

May. 04, 2015USD ($)

Mar. 01, 2015USD ($)

Sep. 29, 2014trusteeagreement

Jul. 31, 2014USD ($)option$ / shares

Jul. 09, 2014USD ($)$ / sharesshares

Jun. 01, 2014USD ($)optionparking_space

May. 09, 2014USD ($)companyshares

Feb. 29, 2012

Jun. 30, 2014USD ($)shares

Feb. 28, 2015USD ($)

Jun. 30, 2014USD ($)shares

Dec. 31, 2014USD ($)

Jul. 31, 2015$ / shares

May. 31, 2014USD ($)

May. 08, 2014

SIR

Related Party Transaction [Line Items]

Ownership percentage prior to transaction

100.00%

Less than wholly owned subsidiary, common shares owned (in shares) | shares

22,000,000

22,000,000

Equity method investments, ownership percentage

0.00%

44.10%

44.10%

Equity investments, common shares sold (in shares) | shares

22,000,000

Price per common share (in dollars per share) | $ / shares

$ 32.04

Equity investments, proceeds from sale

$ 704,800,000

Amended Agreement

Related Party Transaction [Line Items]

Base business management fee payable percentage

10.00%

10.00%

Minimum

Related Party Transaction [Line Items]

Price per common share during one year period after date (in dollars per share) | $ / shares

$ 26

Price per common share during first and second year after date (in dollars per share) | $ / shares

$ 26

Minimum | Subsequent event

Related Party Transaction [Line Items]

Price per common share during one year period after date (in dollars per share) | $ / shares

$ 26

Equity Group Investments and associated entities

Related Party Transaction [Line Items]

Lease term

7 months

1 year

Number of renewal options of lease arrangement | option

1

1

Renewal term of lease arrangement

3 months

3 months

Lease payment, initial term

$ 200,000

$ 200,000

Lease payment

$ 200,000

Term of license agreement

1 year

License fee

$ 100,000

$ 200,000

Number of parking spaces | parking_space

1

Equity Group Investments and associated entities | Subsequent event

Related Party Transaction [Line Items]

Lease term

5 years

Number of renewal options of lease arrangement | option

1

Renewal term of lease arrangement

5 years

Lease payment, initial term

$ 500,000

Lease payment

$ 800,000

Related/Corvex

Related Party Transaction [Line Items]

Due to related persons

33,500,000

Amount of reimbursements payable to related party upon the approval of shareholders

$ 16,700,000

Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period after the date on which the reimbursement is approved by shareholders

8,400,000

Amount of reimbursements payable to related party if specified minimum common share price maintain during the one year period between the first and second anniversaries of the date on which the reimbursement is approved by shareholders

$ 8,400,000

Related/Corvex | Subsequent event

Related Party Transaction [Line Items]

Amount of reimbursements payable to related party upon the approval of shareholders

$ 8,400,000

RMR

Related Party Transaction [Line Items]

Number of primary agreements | agreement

3

Number of managing trustees | trustee

1

Business management fees

$ 16,300,000

$ 31,700,000

Portion of shares issued in payment of management fee (in shares) | shares

68,206

Property management and construction supervision fees

6,800,000

$ 13,800,000

Legal fees and costs

1,500,000

5,400,000

RMR and RMR Australia

Related Party Transaction [Line Items]

Monthly management transition fee

$ 100,000

$ 1,200,000

RMR Australia

Related Party Transaction [Line Items]

Business and property management fees

$ 400,000

$ 900,000

AIC

Related Party Transaction [Line Items]

Equity method investments, ownership percentage

12.50%

Equity investments, common shares sold (in shares) | shares

20,000

Equity investments, proceeds from sale

$ 5,800,000

Amount invested in equity investee

$ 5,200,000

Number of other companies which are shareholders of related party | company

5

Coverage amount for property insurance

$ 500,000,000

Subsequent Events - Narrative (

Subsequent Events - Narrative (Details) $ in Millions	Aug. 04, 2015USD ($)ft²building	Aug. 03, 2015USD ($)	Jul. 31, 2015USD ($)claim	Jul. 24, 2015USD ($)	Jul. 17, 2015USD ($)	May. 01, 2015USD ($)	Jan. 31, 2013building	Jun. 30, 2015ft²building	Jun. 30, 2014ft²
Subsequent Event [Line Items]
Number of buildings sold | building							18
Property square feet | ft²								29,385,000	42,920,000
5.75% unsecured senior notes due 2015
Subsequent Event [Line Items]
Amount defeased						$ 138.8
Disposed of by Sale
Subsequent Event [Line Items]
Number of buildings sold | building								83
Property square feet | ft²								10,834,604
Subsequent event
Subsequent Event [Line Items]
Property square feet | ft²	2,090,162
Gross proceeds from sale of real estate anticipated	$ 376
Number of previously disclosed actions | claim			2
Payments for legal settlement			$ 0.2	$ 0.1	$ 0.1
Subsequent event | 111 East Wacker Drive [Member] | Mortgage notes
Subsequent Event [Line Items]
Amount defeased		$ 141.4
Subsequent event | Disposed of by Sale | Illinois Center [Member]
Subsequent Event [Line Items]
Number of buildings sold | building	2