Tier Reit (TIER) 10-Q 7 Aug 17 2017 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 31, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	TIER REIT INC
Entity Central Index Key	1,176,373
Document Type	10-Q
Document Period End Date	Jun. 30, 2017
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		47,843,037
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q2

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Real estate
Land	$ 141,010	$ 143,537
Land held for development	45,059	45,059
Buildings and improvements, net	1,145,496	1,043,641
Real estate under development	8,128	17,961
Total real estate	1,339,693	1,250,198
Cash and cash equivalents	28,763	14,884
Restricted cash	10,953	7,509
Accounts receivable, net	62,413	71,459
Prepaid expenses and other assets	16,399	25,305
Investments in unconsolidated entities	25,530	76,813
Deferred financing fees, net	2,089	2,395
Lease intangibles, net	93,090	61,844
Other intangible assets, net	1,846	9,787
Assets associated with real estate held for sale	0	32,346
Total assets	1,580,776	1,552,540
Liabilities
Notes payable, net	779,244	826,783
Accounts payable and accrued liabilities	64,412	74,458
Acquired below-market leases, net	20,653	6,886
Distributions payable	0	8,601
Other liabilities	9,606	14,353
Obligations associated with real estate held for sale	0	943
Total liabilities	873,915	932,024
Commitments and contingencies
Equity
Preferred stock, $.0001 par value per share; 17,500,000 shares authorized at June 30, 2017, and December 31, 2016, respectively, none outstanding	0	0
Convertible stock, $.0001 par value per share; 1,000 shares authorized, none outstanding	0	0
Common stock, $.0001 par value per share; 382,499,000 shares authorized, 47,542,066 and 47,473,218 shares issued and outstanding at June 30, 2017, and December 31, 2016, respectively	5	5
Additional paid-in capital	2,608,260	2,606,098
Cumulative distributions and net loss attributable to common stockholders	(1,901,820)	(1,986,515)
Accumulated other comprehensive loss	(274)	(1,042)
Stockholders’ equity	706,171	618,546
Noncontrolling interests	690	1,970
Total equity	706,861	620,516
Total liabilities and equity	$ 1,580,776	$ 1,552,540

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (unaudited) (Parenthetical) - $ / shares	Jun. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (shares)	17,500,000	17,500,000
Preferred stock, shares outstanding (shares)	0	0
Convertible stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Convertible stock, shares authorized (shares)	1,000	1,000
Convertible stock, shares outstanding (shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (shares)	382,499,000	382,499,000
Common stock, shares issued (shares)	47,542,066	47,473,218
Common stock, shares outstanding (shares)	47,542,066	47,473,218

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Statement [Abstract]
Rental revenue	$ 54,552	$ 64,267	$ 110,915	$ 132,745
Expenses
Property operating expenses	13,930	19,805	28,620	40,290
Interest expense	8,235	13,447	17,015	25,687
Real estate taxes	8,753	9,429	17,313	20,493
Property management fees	72	226	132	510
Asset impairment losses	0	0	0	4,826
General and administrative	5,626	5,820	11,333	12,324
Depreciation and amortization	22,652	30,797	47,181	62,841
Total expenses	59,268	79,524	121,594	166,971
Interest and other income	783	344	1,101	618
Loss on early extinguishment of debt	0	0	(545)	0
Loss before income taxes, equity in operations of investments, and gains	(3,933)	(14,913)	(10,123)	(33,608)
Benefit (provision) for income taxes	149	(281)	(95)	(463)
Equity in operations of investments	6,556	823	6,300	1,238
Income (loss) before gains	2,772	(14,371)	(3,918)	(32,833)
Gain on sale of assets	1,262	5,010	92,012	10,749
Gain on remeasurement of investment in unconsolidated entities	0	0	14,168	0
Net income (loss)	4,034	(9,361)	102,262	(22,084)
Noncontrolling interests	(3)	9	(60)	25
Net income (loss) attributable to common stockholders	$ 4,031	$ (9,352)	$ 102,202	$ (22,059)
Weighted average common shares outstanding - basic (in shares)	47,536,320	47,405,767	47,523,688	47,397,679
Weighted average common shares outstanding - diluted (in shares)	47,875,418	47,405,767	47,727,634	47,397,679
Diluted weighted average common shares outstanding
Basic income (loss) per common share (in dollars per share)	$ 0.08	$ (0.20)	$ 2.14	$ (0.47)
Diluted income (loss) per common share (in dollars per share)	0.08	(0.20)	2.13	(0.47)
Distributions declared per common share (in dollars per share)	$ 0.18	$ 0.18	$ 0.36	$ 0.36
Comprehensive income (loss):
Other comprehensive income (loss): unrealized income (loss) on interest rate derivatives	$ (1,301)	$ (2,532)	$ 768	$ (15,412)
Comprehensive income (loss)	2,733	(11,893)	103,030	(37,496)
Comprehensive (income) loss attributable to noncontrolling interests	(2)	11	(60)	35
Comprehensive income (loss) attributable to common stockholders	$ 2,731	$ (11,882)	$ 102,970	$ (37,461)

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Changes in Equity (unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Cumulative Distributions and Net Loss Attributable to Common Stockholders	Accumulated Other Comprehensive Loss	Noncontrolling Interests
Beginning balance at Dec. 31, 2015	$ 675,119	$ 5	$ 2,600,193	$ (1,922,721)	$ (3,860)	$ 1,502
Beginning balance (in shares) at Dec. 31, 2015		47,362
Increase (Decrease) in Equity
Net income (loss)	(22,084)			(22,059)		(25)
Unrealized gain (loss) on interest rate derivatives	(15,412)				(15,402)	(10)
Share based compensation, net	1,796		1,721			75
Share-based compensation, net (in shares)		51
Distributions declared, common stock ($0.36 and $0.36 per share for the six months ended June 30, 2017 and 2016, respectively)	(17,188)			(17,188)
Distributions declared, noncontrolling interests	(13)					(13)
Cancellation of Series A Convertible Preferred Stock	2,700		2,700
Ending balance at Jun. 30, 2016	624,918	$ 5	2,604,614	(1,961,968)	(19,262)	1,529
Ending balance (in shares) at Jun. 30, 2016		47,413
Increase (Decrease) in Equity
Cumulative effect of a change in accounting principle			290	(290)
Beginning balance, restated	620,516	$ 5	2,606,388	(1,986,805)	(1,042)	1,970
Beginning balance at Dec. 31, 2016	620,516	$ 5	2,606,098	(1,986,515)	(1,042)	1,970
Beginning balance (in shares) at Dec. 31, 2016		47,473
Increase (Decrease) in Equity
Net income (loss)	102,262			102,202		60
Unrealized gain (loss) on interest rate derivatives	768				768	0
Share based compensation, net	1,604		1,872			(268)
Share-based compensation, net (in shares)		69
Contributions by noncontrolling interests	438					438
Distributions declared, common stock ($0.36 and $0.36 per share for the six months ended June 30, 2017 and 2016, respectively)	(17,217)			(17,217)
Distributions declared, noncontrolling interests	(10)					(10)
Deconsolidation of investment	(1,500)					(1,500)
Ending balance at Jun. 30, 2017	$ 706,861	$ 5	$ 2,608,260	$ (1,901,820)	$ (274)	$ 690
Ending balance (in shares) at Jun. 30, 2017		47,542

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Changes in Equity (unaudited) (Parenthetical) - $ / shares	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Stockholders' Equity [Abstract]
Distributions declared per common share (in dollars per share)	$ 0.18	$ 0.18	$ 0.36	$ 0.36

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities
Net income (loss)	$ 102,262	$ (22,084)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Asset impairment losses	0	4,826
Gain on sale of assets	(92,012)	(10,749)
Gain on remeasurement of investment in unconsolidated entities	(14,168)	0
Loss on early extinguishment of debt	109	0
Hedge ineffectiveness expense from derivatives	1	1,941
Amortization of restricted shares and units	1,933	2,049
Depreciation and amortization	47,181	62,841
Amortization of lease intangibles	(286)	(1,385)
Amortization of above- and below-market rent	(1,788)	(2,463)
Amortization of deferred financing costs	1,679	1,523
Equity in operations of investments	(6,300)	(1,238)
Ownership portion of fees from unconsolidated entities	194	276
Distributions from investments	8,963	300
Change in accounts receivable	(4,207)	(2,177)
Change in prepaid expenses and other assets	(222)	501
Change in lease commissions	(5,368)	(7,185)
Change in other lease intangibles	(387)	(810)
Change in accounts payable and accrued liabilities	(13,515)	(7,526)
Change in other liabilities	1,971	(1,717)
Cash provided by operating activities	26,040	16,923
Cash flows from investing activities
Escrow deposits	(6,000)	0
Return of investments	23,433	15,630
Purchases of real estate	(93,011)	0
Investments in unconsolidated entities	(10,732)	(3,576)
Capital expenditures for real estate	(17,720)	(20,833)
Capital expenditures for real estate under development	(13,992)	(2,909)
Proceeds from sales of assets	330,045	250,319
Cash provided by investing activities	212,023	238,631
Cash flows from financing activities
Financing costs	(1,933)	(868)
Proceeds from notes payable	145,000	107,000
Payments on notes payable	(338,088)	(277,820)
Transfer of common stock	(329)	(253)
Distributions paid to common stockholders	(25,811)	(17,172)
Distributions paid to noncontrolling interests	(17)	(24)
Contributions from noncontrolling interests	438	0
Cash used in financing activities	(220,740)	(189,137)
Net change in cash, cash equivalents, and restricted cash	17,323	66,417
Cash, cash equivalents, and restricted cash at beginning of period	22,393	22,960
Cash, cash equivalents, and restricted cash at end of period	$ 39,716	$ 89,377

Business

Business	6 Months Ended
	Jun. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business	Business Organization TIER REIT, Inc. is a publicly traded (NYSE: TIER), self-managed, Dallas-based real estate investment trust focused on owning quality, well-managed commercial office properties in dynamic markets throughout the U.S. As used herein, “TIER REIT,” the “Company,” “we,” “us,” or “our” refers to TIER REIT, Inc. and its subsidiaries unless the context otherwise requires. TIER REIT’s vision is to be the premier owner and operator of best-in-class office properties in TIER 1 submarkets, which are primarily higher density and amenity-rich locations within select, high-growth metropolitan areas that offer a walkable experience to various amenities. Our mission is to provide unparalleled, TIER ONE Property Services to our tenants and outsized total return through stock price appreciation and dividend growth to our stockholders. TIER REIT was incorporated in June 2002 as a Maryland corporation and has elected to be treated, and currently qualifies, as a real estate investment trust, or REIT, for federal income tax purposes. As of June 30, 2017 , we owned interests in 19 operating office properties, one non-operating property, and three development properties, located in eight markets throughout the United States. Substantially all of our business is conducted through Tier Operating Partnership LP (“Tier OP”), a Texas limited partnership. Our wholly-owned subsidiary, Tier GP, Inc., a Delaware corporation, is the sole general partner of Tier OP. Our direct and indirect wholly-owned subsidiaries, Tier Business Trust, a Maryland business trust, and Tier Partners, LLC, a Delaware limited liability company, are limited partners that together with Tier GP, Inc. own all of Tier OP.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	Basis of Presentation and Significant Accounting Policies Interim Unaudited Financial Information The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and should be read in conjunction with the consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2016, which was filed with the Securities and Exchange Commission (“SEC”) on February 13, 2017. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been omitted from this report on Form 10-Q pursuant to the rules and regulations of the SEC. The results for the interim periods shown in this report are not necessarily indicative of future financial results. The accompanying condensed consolidated balance sheets as of June 30, 2017 , and December 31, 2016 , and condensed consolidated statements of operations and comprehensive income (loss), changes in equity, and cash flows for the periods ended June 30, 2017 and 2016 , have not been audited by our independent registered public accounting firm. In the opinion of management, the accompanying unaudited condensed consolidated financial statements include all adjustments necessary to present fairly our financial position as of June 30, 2017 , and December 31, 2016 , and our results of operations and our cash flows for the periods ended June 30, 2017 and 2016 . These adjustments are of a normal recurring nature. We have evaluated subsequent events for recognition or disclosure in our condensed consolidated financial statements. Summary of Significant Accounting Policies Described below are certain of our significant accounting policies. The disclosures regarding several of the policies have been condensed or omitted in accordance with interim reporting regulations specified by Form 10-Q pursuant to the rules and regulations of the SEC. Please see our consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for a complete listing of our significant accounting policies. Real Estate As of June 30, 2017 , and December 31, 2016 , the cost basis and accumulated depreciation and amortization related to our consolidated depreciable real estate properties and related lease intangibles were as follows (in thousands): Lease Intangibles Assets Liabilities Acquired Above-Market Leases Acquired Below-Market Leases Buildings and Improvements Other Lease Intangibles as of June 30, 2017 Cost $ 1,639,756 $ 154,395 $ 5,004 $ (52,142 ) Less: accumulated depreciation and amortization (494,260 ) (61,964 ) (4,345 ) 31,489 Net $ 1,145,496 $ 92,431 $ 659 $ (20,653 ) Lease Intangibles Assets Liabilities Acquired Above-Market Leases Acquired Below-Market Leases Buildings and Improvements Other Lease Intangibles as of December 31, 2016 Cost $ 1,579,157 $ 131,618 $ 5,005 $ (42,537 ) Less: accumulated depreciation and amortization (535,516 ) (70,672 ) (4,107 ) 35,651 Net $ 1,043,641 $ 60,946 $ 898 $ (6,886 ) We amortize the value of in-place leases, in-place tenant improvements, and in-place leasing commissions to expense over the initial term of the respective leases. The tenant relationship values are amortized to expense over the tenants’ respective initial lease terms and any anticipated renewal periods, but in no event does the amortization period for intangible assets or liabilities exceed the remaining depreciable life of the building. Should a tenant terminate its lease, the unamortized portion of the acquired lease intangibles related to that tenant would be charged to expense. The estimated remaining average useful lives for acquired lease intangibles range from an ending date of July 2017 to an ending date of June 2027. Anticipated amortization associated with acquired lease intangibles for each of the following five years is as follows (in thousands): July 2017 - December 2017 $ 1,922 2018 $ 3,551 2019 $ 3,568 2020 $ 3,675 2021 $ 3,340 Impairment of Real Estate-Related Assets For our consolidated real estate assets, we monitor events and changes in circumstances indicating that the carrying amounts of the real estate assets may not be recoverable. When such events or changes in circumstances are present, we assess potential impairment by comparing estimated future undiscounted cash flows expected to be generated over the life of the asset including its eventual disposition, to the carrying amount of the asset. In the event that the carrying amount exceeds the estimated future undiscounted cash flows and also exceeds the fair value of the asset, we recognize an impairment loss to adjust the carrying amount of the asset to its estimated fair value. Our process to estimate the fair value of an asset involves using bona fide purchase offers or the expected sales price of an executed sales agreement, which would be considered Level 1 or Level 2 assumptions within the fair value hierarchy. To the extent that this type of third-party information is unavailable, we estimate projected cash flows and a risk-adjusted rate of return that we believe would be used by a third party market participant in estimating the fair value of an asset. This is considered a Level 3 assumption within the fair value hierarchy. These projected cash flows are prepared internally by the Company’s asset management professionals and are updated quarterly to reflect in-place and projected leasing activity, market revenue and expense growth rates, market capitalization rates, discount rates, and changes in economic and other relevant conditions. The Company’s Chief Financial Officer, Senior Vice President - Accounting, and Managing Director - Asset Management review these projected cash flows to assure that the valuation is prepared using reasonable inputs and assumptions which are consistent with market data or with assumptions that would be used by a third party market participant and assume the highest and best use of the real estate investment. We had no impairment charges for the six months ended June 30, 2017 . For the six months ended June 30, 2016 , we recorded a non-cash impairment charge totaling approximately $4.8 million related to the impairment of a consolidated real estate asset assessed for impairment due to a change in management’s estimate of the intended hold period. For our unconsolidated real estate assets, at each reporting date we compare the estimated fair value of our investment to the carrying amount. An impairment charge is recorded to the extent the fair value of our investment is less than the carrying amount and the decline in value is determined to be other than a temporary decline. We had no impairment charges related to our investments in unconsolidated entities for the six months ended June 30, 2017 and 2016 . In evaluating our investments for impairment, management makes several estimates and assumptions, including, but not limited to, the projected date of disposition (the intended hold period) and sales price for each property, the estimated future cash flows of each property during our estimated ownership period, and for unconsolidated investments, the estimated future distributions from the investment. A change in these estimates and assumptions could result in understating or overstating the carrying amount of our investments which could be material to our financial statements. We undergo continuous evaluations of property level performance, credit market conditions, and financing options. If our assumptions regarding the cash flows expected to result from the use and eventual disposition of our properties decrease or our expected hold periods decrease, we may incur future impairment charges on our real estate-related assets. In addition, we may incur impairment charges on assets classified as held for sale in the future if the carrying amount of the asset upon classification as held for sale exceeds the estimated fair value, less costs to sell. Cash, Cash Equivalents, and Restricted Cash We consider investments in highly-liquid money market funds or investments with original maturities of three months or less to be cash equivalents. Restricted cash includes restricted money market accounts, as required by our lenders or by leases, for anticipated tenant improvements, property taxes and insurance, certain tenant security deposits, and additional loan security reserves. We early adopted new Financial Accounting Standards Board (“FASB”) guidance on December 31, 2016, which changes the presentation of our statements of cash flows and related disclosures for all periods presented, and accordingly, the following is a summary of our total cash, cash equivalents, and restricted cash as presented in our statements of cash flows for the six months ended June 30, 2017 and 2016 (in thousands): June 30, June 30, 2016 Cash and cash equivalents $ 28,763 $ 78,599 Restricted cash 10,953 10,778 Total cash, cash equivalents, and restricted cash $ 39,716 $ 89,377 Accounts Receivable, net The following is a summary of our accounts receivable as of June 30, 2017 , and December 31, 2016 (in thousands): June 30, December 31, Straight-line rental revenue receivable $ 58,231 $ 68,287 Tenant receivables 3,544 5,047 Non-tenant receivables 1,437 691 Allowance for doubtful accounts (799 ) (2,566 ) Total $ 62,413 $ 71,459 Our allowance for doubtful accounts is an estimate based on management’s evaluation of accounts where it has determined that a tenant may not meet its financial obligations. In these situations, management uses its judgment, based on the facts and circumstances, and records a reserve for that tenant against amounts due to reduce the receivable to an amount it believes is collectible. These reserves are reevaluated and adjusted as additional information becomes available. Investments in Unconsolidated Entities Investments in unconsolidated entities consist of our noncontrolling interests in properties. We account for these investments using the equity method of accounting in accordance with GAAP. We use the equity method of accounting when we have significant influence, but not control, of the operating and financial decisions of these investments and thereby have some responsibility to create a return on our investment. The equity method of accounting requires these investments to be initially recorded at cost and subsequently increased (decreased) for our share of net income (loss), including eliminations for our share of inter-company transactions, and increased (decreased) for contributions (distributions). To the extent that we contribute assets to an unconsolidated entity, our investment in the unconsolidated entity is recorded at our cost basis in the assets that were contributed to the entity. To the extent that our cost basis is different than the basis reflected at the entity level, the basis difference is generally amortized over the life of the related asset and included in our share of equity in operations of investments. For unconsolidated investments that have properties under development, we capitalize interest expense to our investment basis using our weighted average interest rate of consolidated debt. Capitalization begins when we are engaged in the activities necessary to get the property ready for its intended use. We cease capitalization when the development is completed and ready for its intended use or if the intended use changes such that capitalization is no longer appropriate. For the six months ended June 30, 2017 and 2016, we capitalized interest expense of approximately $0.7 million and $0.3 million , respectively, for unconsolidated entities with properties under development, which is included in our investments in unconsolidated entities on our condensed consolidated balance sheets. Other Intangible Assets, net Other intangible assets consist of below-market ground leases on properties where a third party owns and has leased the underlying land to us. As of June 30, 2017 , and December 31, 2016 , the cost basis and accumulated amortization related to our consolidated other intangible assets were as follows (in thousands): June 30, December 31, Cost $ 2,978 $ 11,277 Less: accumulated amortization (1,132 ) (1,490 ) Net $ 1,846 $ 9,787 Revenue Recognition We recognize rental income generated from all leases of consolidated real estate assets on a straight-line basis over the terms of the respective leases, including the effect of rent holidays, if any. The total net increase to rental revenue due to straight-line rent adjustments for the three months ended June 30, 2017 and 2016 , was approximately $2.0 million and $1.3 million , respectively. The total net increase to rental revenue due to straight-line rent adjustments for both the six months ended June 30, 2017 and 2016 , was approximately $3.8 million . When a tenant exceeds its tenant improvement allowance, this amount is reimbursed to us and recorded as a deferred rent liability, which is recognized as rental revenue over the life of the lease. The total net increase to rental revenue due to this deferred rent for the three months ended June 30, 2017 and 2016 , was approximately $0.4 million and $0.9 million , respectively. The total net increase to rental revenue due to this deferred rent for the six months ended June 30, 2017 and 2016 , was approximately $1.0 million and $1.9 million , respectively. Our rental revenue also includes amortization of acquired above- and below-market leases. The total net increase to rental revenue due to the amortization of acquired above- and below-market leases for the three months ended June 30, 2017 and 2016 , was approximately $0.9 million and $1.1 million , respectively. The total net increase to rental revenue due to the amortization of acquired above- and below-market leases for the six months ended June 30, 2017 and 2016 , was approximately $1.8 million and $2.5 million , respectively. Revenues relating to lease termination fees are recognized on a straight-line basis amortized from the time that a tenant’s right to occupy the leased space is modified through the end of the revised lease term. For the three months ended June 30, 2017 and 2016 , we recognized lease termination fees of approximately $0.1 million and $0.7 million , respectively. For the six months ended June 30, 2017 and 2016 , we recognized lease termination fees of approximately $0.2 million and $1.3 million , respectively.

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2017
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements Recently Adopted Accounting Pronouncements In March 2016, the FASB issued guidance which affects accounting for certain aspects of share-based payments for employees. The guidance requires income statement recognition of income tax effects of the awards when the awards vest or are settled. The guidance also changes the employer’s accounting for forfeitures as well as for an employee’s use of shares to satisfy their income tax withholding obligations. We have elected to recognize forfeitures as they occur. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2016, with early adoption permitted. We adopted this guidance using the modified retrospective approach on January 1, 2017, and recorded a cumulative-effect adjustment of approximately $0.3 million to retained earnings to recognize forfeitures as they occur. In March 2016, the FASB issued amended guidance which simplifies the accounting for equity method investments by removing the requirement that an entity retroactively adopt the equity method of accounting if an investment qualifies for use of the equity method as a result of an increase in the level of ownership or degree of influence. The amendment requires that the equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor’s previously held interest and adopt the equity method of accounting as of the date the investment becomes qualified for equity method accounting. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2016, with early adoption permitted. The adoption of this guidance on January 1, 2017, did not have a material impact on our financial statements or disclosures. New Accounting Pronouncements to be Adopted In May 2014, the FASB issued guidance to clarify the principles for recognizing revenue and to develop a common revenue standard for GAAP and International Financial Reporting Standards. The standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers. Lease contracts will be excluded from this revenue recognition criteria; however, the sale of real estate will be required to follow the new model. Expanded quantitative and qualitative disclosures regarding revenue recognition will be required for contracts that are subject to this guidance. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2017, with early adoption permitted only as of annual reporting periods beginning after December 15, 2016. The guidance permits two implementation approaches, one requiring retrospective application of the new standard with restatement of prior years and one requiring prospective application of the new standard with disclosure of results under old standards. We are currently evaluating the impact the guidance will have on our financial statements when adopted, but we believe the impact could primarily relate to sales of properties, timing of revenue recognition, and the ability to capitalize certain internal costs. In February 2016, the FASB issued updated guidance which sets out revised principles for the recognition, measurement, presentation and disclosure of leases for both lessees and lessors. The guidance requires lessees to recognize assets and liabilities for operating leases with lease terms greater than twelve months on the balance sheet. The guidance further modifies lessors’ classification criteria for leases and the accounting for sales-type and direct financing leases. New disclosures regarding the amount, timing, and uncertainty of cash flows arising from leases are also required. The guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2018, with early adoption permitted and is required to be adopted using the modified retrospective approach. Upon adoption, the Company will recognize a lease liability and a right-of-use asset for operating leases where it is the lessee, such as ground leases and office and equipment leases. We are currently evaluating the impact this guidance will have on our financial statements when adopted. In June 2016, the FASB issued amended guidance which requires measurement and recognition of expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. This is different from the current guidance as this will require immediate recognition of estimated credit losses expected to occur over the remaining life of many financial assets. Financial assets that are measured at amortized cost will be required to be presented at the net amount expected to be collected with an allowance for credit losses deducted from the amortized cost basis. Generally, the pronouncement requires a modified retrospective method of adoption. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2019, with early adoption permitted. We are currently evaluating the impact this guidance will have on our financial statements when adopted. In August 2016, the FASB issued amended guidance on classification of certain cash receipts and payments in the statement of cash flows. Of the eight types of cash flows discussed in the new standard, we believe the classification of debt prepayment and debt extinguishment costs as financing outflows will impact the Company as these items are currently reflected as operating outflows. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2017, with early adoption permitted and is required to be applied retrospectively to all periods presented. We will continue to evaluate the impact this guidance will have on our financial statements when adopted. In February 2017, the FASB issued updated guidance that clarifies the scope of asset derecognition guidance, adds guidance for partial sales of nonfinancial assets and clarifies recognizing gains and losses from the transfer of nonfinancial assets in contracts with noncustomers. This guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2017, with early adoption permitted only as of annual reporting periods beginning after December 15, 2016. We are currently evaluating the impact this guidance will have on our financial statements when adopted. In May 2017, the FASB issued updated guidance on applying modification accounting to changes in the terms or conditions of a share-based payment award. Under the new guidance, modification accounting is required only if the fair value, the vesting conditions, or the classification of the award (as equity or liability) changes as a result of the change in terms or conditions. The guidance is effective for fiscal years and interim periods within those years beginning after December 15, 2017, with early adoption permitted. We are currently evaluating the impact this guidance will have on our financial statements when adopted.

Real Estate Activities

Real Estate Activities	6 Months Ended
	Jun. 30, 2017
Real Estate Activities [Abstract]
Real Estate Activities	Real Estate Activities Sales of Real Estate The following table presents our sales of real estate for the six months ended June 30, 2017 (in thousands): Property Name Date of Sale Location Rentable Square Footage Contract Sale Price Proceeds from Sale Buena Vista Plaza 01/18/17 Burbank, CA 115 $ 52,500 $ 47,498 Three Parkway 03/01/17 Philadelphia, PA 561 95,000 91,876 Eisenhower I (1) 03/13/17 Tampa, FL 130 31,400 30,742 Third + Shoal (2) 03/31/17 Austin, TX N/A 14,955 14,525 Louisville Portfolio (3) 06/26/17 Louisville, KY 678 71,500 68,626 1,484 $ 265,355 $ 253,267 __________________ (1) We may be entitled to receive an additional $3.0 million subject to certain future events. (2) We sold a 50% interest in our 95% interest in the Third + Shoal development property. (3) The Louisville Portfolio consists of five properties located in Louisville, Kentucky. Properties that have been sold contributed income of approximately $1.0 million and loss of approximately $0.5 million to our net income (loss) for the three months ended June 30, 2017 and 2016 , respectively. Properties that have been sold contributed income of approximately $2.5 million and loss of approximately $5.4 million to our net income (loss) for the six months ended June 30, 2017 and 2016 , respectively. These amounts exclude any gains on the sales of these properties. Acquisitions of Real Estate On January 4, 2017, we acquired the remaining 50.16% interest in Domain Junction LLC, the entity that owns Domain 2 and Domain 7, increasing our ownership interest in these properties to 100% , for a contract purchase price of approximately $51.2 million plus assumed debt of approximately $40.1 million . As a result of obtaining a controlling interest in the entity, we recognized a gain of approximately $14.2 million from the remeasurement of our previously held equity interest at fair value. Assets acquired and liabilities assumed were recorded at their relative fair values upon consolidation of the properties, and include lease intangible assets of approximately $16.6 million and acquired below-market leases of approximately $9.4 million . The estimated remaining average useful lives for these acquired lease intangibles range from an ending date of December 2022 to an ending date of February 2026. On June 23, 2017, we acquired Legacy District One for a contract purchase price of approximately $123.3 million , which included approximately $66.0 million in assumed mortgage debt secured by the property. Legacy District One is located in Plano, Texas, and contains approximately 319,000 rentable square feet. The debt matures in January 2023 and has a fixed stated annual interest rate of 4.24% . Assets acquired and liabilities assumed were recorded at their relative fair values and include lease intangible assets of approximately $20.0 million and acquired below-market leases of approximately $6.4 million . The estimated remaining average useful lives for these acquired lease intangibles all have an ending date of June 2027. Real Estate Held for Sale We had no properties held for sale as of June 30, 2017 . As of December 31, 2016, four of our properties (One Oxmoor Place, Steeplechase Place, Lakeview, and Hunnington) were held for sale. These properties were sold in June 2017. The major classes of assets and obligations associated with real estate held for sale as of December 31, 2016, were as follows (in thousands): December 31, 2016 Land $ 5,481 Buildings and improvements, net of approximately $11.8 million in accumulated depreciation 24,837 Accounts receivable and other assets 665 Lease intangibles, net of approximately $2.1 million in accumulated amortization 1,363 Assets associated with real estate held for sale $ 32,346 Acquired below-market leases, net of approximately $0.2 million in accumulated amortization $ 44 Other liabilities 899 Obligations associated with real estate held for sale $ 943

Real Estate Under Development

Real Estate Under Development	6 Months Ended
	Jun. 30, 2017
Real Estate Under Development [Abstract]
Real Estate Under Development	Real Estate Under Development When we are engaged in activities to get a potential development ready for its intended use, we capitalize interest, property taxes, insurance, ground lease payments, and direct construction costs. For the six months ended June 30, 2017 , we capitalized a total of approximately $8.9 million , including approximately $0.6 million in interest. For the six months ended June 30, 2016 , we capitalized a total of approximately $3.8 million , which included approximately $0.1 million capitalized interest. These costs are classified as real estate under development on our condensed consolidated balance sheets until such time that the development is complete.

Investments in Unconsolidated E

Investments in Unconsolidated Entities	6 Months Ended
	Jun. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Investments in Unconsolidated Entities	Investments in Unconsolidated Entities We participate in real estate ventures for the purpose of acquiring and developing office properties in which we may or may not have a controlling financial interest. Our investments in unconsolidated entities consist of our noncontrolling interests in certain properties that are accounted for using the equity method of accounting. The following is a summary of our investments in unconsolidated entities as of June 30, 2017 , and December 31, 2016 (dollar amounts in thousands): Ownership Interest Unconsolidated Investment Balance Entity Name Property June 30, December 31, 2016 June 30, December 31, Domain Junction LLC (1) Domain 2 & Domain 7 100.00 % 49.84 % $ — $ 9,770 Domain Junction 8 Venture LLC (2)(3) Domain 8 50.00 % 50.00 % 1,469 18,093 TR 208 Nueces Member, LLC (4) Third + Shoal 47.50 % 95.00 % 24,061 — COLDC 54 Holdings, LLC (3)(5) Colorado Building — 10.00 % — 711 GSTDC 72 Holdings, LLC (3)(5) 1325 G Street — 10.00 % — 3,719 1301 Chestnut Associates, L.P. (6) Wanamaker Building 1.10 % 60.00 % — 44,520 Total (7) ` $ 25,530 $ 76,813 _________________ (1) On January 4, 2017, we acquired our unrelated third party’s 50.16% interest in Domain Junction LLC increasing our ownership interest to 100% , and these properties were consolidated. (2) All major decisions for this entity are made by the other owner. (3) We have evaluated our investments in unconsolidated entities in order to determine if they are VIEs. Based on our assessment, we have identified each of these entities as a VIE, but we are not the primary beneficiary, as we do not have the power to direct the activities that most significantly impact the economic performance of these entities. For these VIEs in which we are not deemed to be the primary beneficiary, we continue to account for them using the equity method. The maximum amount of exposure to loss with respect to these VIEs is the carrying amount of our investment. At June 30, 2017 , these VIEs have total assets of approximately $84.9 million and total liabilities of approximately $90.6 million . At December 31, 2016 , our VIEs had total assets of approximately $353.5 million and total liabilities of approximately $262.8 million . (4) On March 31, 2017, we sold a 50% interest in the entity that owns a 95% interest in Third + Shoal, resulting in this property being deconsolidated as control of this property is now shared. (5) On April 27, 2017, the Colorado Building and 1325 G Street were sold for a combined contract sales price of $259.0 million (at 100%). (6) On January 17, 2017, we sold substantially all of our noncontrolling investment in 1301 Chestnut Associates, L.P. At June 30, 2017 , our remaining 1.1% interest is accounted for using the cost method and is included in “prepaid expenses and other assets” on our condensed consolidated balance sheet. (7) Our investment in unconsolidated entities at June 30, 2017, and December 31, 2016, includes basis adjustments that total approximately $8.8 million and $7.2 million , respectively. These amounts represent the aggregate difference between our historical cost basis and our equity basis reflected at the joint venture level, which is typically amortized over the life of the related assets and liabilities. Basis differences occur from impairment of investments and upon the transfer of assets that were previously owned by us into a joint venture. In addition, certain acquisition, transaction, and other costs may not be reflected in the net assets at the joint venture level. Our equity in operations of investments represents our proportionate share of the combined earnings and losses of our investments for the period of our ownership and in 2017, include combined gains on the sales of 1325 G Street and the Colorado Building of approximately $6.7 million . For the three months ended June 30, 2017 and 2016, we recorded approximately $6.6 million and $0.8 million , respectively, for our share of equity in operations from our investments in unconsolidated entities. For the six months ended June 30, 2017 and 2016, we recorded approximately $6.3 million and $1.2 million , respectively, for our share of equity in operations from our investments in unconsolidated entities.

Notes Payable, net

Notes Payable, net	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Notes Payable, net	Notes Payable, net Our notes payable, net were approximately $779.2 million as of June 30, 2017 . Approximately $192.0 million of these notes payable, net were secured by real estate assets with a carrying value of approximately $256.1 million as of June 30, 2017 . As of June 30, 2017 , all of our outstanding debt was fixed rate debt (or effectively fixed rate debt, through the use of interest rate swaps), with the exception of approximately $70.0 million . As of June 30, 2017 , the stated annual interest rates on our outstanding debt, ranged from approximately 2.58% to 6.09% . As of June 30, 2017 , the effective weighted average interest rate for our consolidated debt is approximately 3.74% . For our loan that is in default and detailed below, we incur a default interest rate that is 500 basis points higher than the stated interest rate, which resulted in an overall effective weighted average interest rate of approximately 4.05% as of June 30, 2017 , for our consolidated debt and additional interest expense of approximately $1.2 million for the six months ended June 30, 2017 . We anticipate, although we can provide no assurance, that when the property to which such loan relates is sold, or if ownership of this property is conveyed to the lender, the default interest will be forgiven. Our loan agreements generally require us to comply with certain reporting and financial covenants. As of June 30, 2017 , we were in default on a non-recourse property loan with an outstanding balance of approximately $48.2 million secured by our Fifth Third Center property located in Columbus, Ohio, which has a carrying value of approximately $32.4 million as of June 30, 2017 . A receiver was appointed for this property in March 2016. The loan had an original maturity date of July 2016, and we are currently working with the lender to dispose of this property on its behalf, although there can be no assurance regarding such disposition. As of June 30, 2017 , other than the default discussed above, we believe we were in compliance with the covenants under each of our loan agreements, including our credit facility. Excluding debt already matured as detailed above, our outstanding consolidated debt has maturity dates that range from December 2018 to January 2023. The following table provides information regarding the timing of principal payments of our notes payable, net as of June 30, 2017 (in thousands): Principal payments due in: July 2017 - December 2017 $ 48,867 2018 21,501 2019 301,589 2020 1,670 2021 72,416 Thereafter 341,000 Less: unamortized debt issuance costs (1) (7,799 ) Notes payable, net $ 779,244 ________________ (1) Excludes approximately $2.1 million of unamortized debt issuance costs associated with the revolving line of credit because these costs are presented as an asset on our condensed consolidated balance sheets. Credit Facility We have a credit agreement through our operating partnership, Tier OP, that provides for total unsecured borrowings of up to $860.0 million , subject to our compliance with certain financial covenants. The facility consists of a $300.0 million term loan, a $275.0 million term loan, and a $285.0 million revolving line of credit. The first term loan matures on December 18, 2019. The second term loan matures on June 30, 2022. The revolving line of credit matures on December 18, 2018, and can be extended one additional year subject to certain conditions and payment of an extension fee. The annual interest rate on the credit facility is equal to either, at our election, (1) the “base rate” (calculated as the greatest of (i) the agent’s “prime rate”; (ii) 0.5% above the Federal Funds Effective Rate; or (iii) the LIBOR Market Index Rate plus 1.0% ) plus the applicable margin or (2) LIBOR for an interest period of one , three , or six months plus the applicable margin. The applicable margin will be determined based on the ratio of total indebtedness to total asset value and ranges from 35 basis points to 250 basis points. We have entered into interest rate swap agreements to hedge interest rates on $525.0 million of these borrowings to manage our exposure to future interest rate movements. All amounts owed are guaranteed by us and certain subsidiaries of Tier OP. As of June 30, 2017 , we had approximately $575.0 million in borrowings outstanding under the term loans, and $20.0 million in borrowings outstanding under the revolving line of credit with the ability, subject to our most restrictive financial covenants, to borrow an additional approximately $161.4 million under the facility as a whole. As of June 30, 2017 , the weighted average effective interest rate for borrowings under the credit facility as a whole, inclusive of our interest rate swaps, was approximately 3.23% .

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements Fair value, as defined by GAAP, is a market-based measurement, not an entity-specific measurement. Therefore, a fair value measurement should be determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair value measurements, a fair value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the fair value hierarchy) and the reporting entity’s own assumptions about market participant assumptions (unobservable inputs classified within Level 3 of the fair value hierarchy) has been established. Assets and Liabilities Measured at Fair Value on a Recurring Basis Derivative financial instruments We use derivative financial instruments, such as interest rate swaps, to manage our interest rate risk. The valuation of these instruments is determined using widely accepted valuation techniques including discounted cash flow analysis of the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs, including interest rate curves and implied volatilities. The fair values of interest rate swaps are determined using the market standard methodology of netting the discounted future fixed cash receipts (or payments) and the discounted expected variable cash payments (or receipts). The variable cash payments (or receipts) are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. We incorporate credit valuation adjustments (“CVAs”) to appropriately reflect both our own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of our derivative contracts for the effect of nonperformance risk, we have considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees. 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 CVAs associated with our derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by us and our counterparties. However, we have assessed the significance of the impact of the CVAs on the overall valuation of our derivative positions and have determined that they are not significant. As a result, we have determined that our derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. Unrealized gains or losses on derivatives are recorded in accumulated other comprehensive income (loss) (“OCI”) within equity at each measurement date. Our derivative financial instruments are included in “prepaid expenses and other assets” and “other liabilities” on our condensed consolidated balance sheets. The following table sets forth our financial assets and liabilities measured at fair value on a recurring basis, which equals book value, by level within the fair value hierarchy as of June 30, 2017 , and December 31, 2016 (in thousands). Basis of Fair Value Measurements Quoted Prices In Active Markets for Identical Items (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Description June 30, 2017 Derivative financial instruments: Assets $ 988 $ — $ 988 $ — Liabilities $ (691 ) $ — $ (691 ) $ — December 31, 2016 Derivative financial instruments: Assets $ 1,182 $ — $ 1,182 $ — Liabilities $ (1,652 ) $ — $ (1,652 ) $ — Financial Instruments not Reported at Fair Value Financial instruments held at June 30, 2017 , and December 31, 2016 , but not measured at fair value on a recurring basis include cash and cash equivalents, restricted cash, accounts receivable, notes payable, accounts payable and accrued liabilities, distributions payable, and other liabilities. With the exception of notes payable, the financial statement carrying amounts of these items approximate their fair values due to their short-term nature. Estimated fair values for notes payable have been determined using recent trading activity and/or bid-ask spreads and are classified as Level 2 in the fair value hierarchy. Carrying amounts of our notes payable and the related estimated fair value as of June 30, 2017 , and December 31, 2016 , are as follows (in thousands): June 30, 2017 December 31, 2016 Carrying Amount Fair Value Carrying Amount Fair Value Notes payable $ 787,043 $ 791,317 $ 834,131 $ 837,878 Less: unamortized debt issuance costs (7,799 ) (7,348 ) Notes payable, net $ 779,244 $ 826,783

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities We may be exposed to the risk associated with variability of interest rates that might impact our cash flows and the results of our operations. 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 have used interest rate swaps as part of our interest rate risk management strategy. Our interest rate swaps involve the receipt of variable-rate amounts from counterparties in exchange for us making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. Our hedging strategy of entering into interest rate swaps, therefore, is to eliminate or reduce, to the extent possible, the volatility of cash flows. The following table summarizes the notional values of our derivative financial instruments (in thousands) as of June 30, 2017 . The notional values provide an indication of the extent of our involvement in these instruments at June 30, 2017 , but do not represent exposure to credit, interest rate, or market risks. Type/Description Notional Value Index Strike Rate Effective Date Maturity Date Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.6775 % 12/31/14 10/31/19 Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.6935 % 04/30/15 10/31/19 Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.7615 % 06/30/15 05/31/22 Interest rate swap - cash flow hedge $ 150,000 one-month LIBOR 1.7695 % 06/30/15 05/31/22 The table below presents the fair value of our derivative financial instruments, included in “prepaid expenses and other assets” and “other liabilities” on our condensed consolidated balance sheets, as of June 30, 2017 , and December 31, 2016 (in thousands): Derivatives designated as hedging instruments: Derivative Assets Derivative Liabilities June 30, December 31, June 30, December 31, Interest rate swaps $ 988 $ 1,182 $ (691 ) $ (1,652 ) The tables below present the effect of the change in fair value of derivative financial instruments in our condensed consolidated statements of operations and comprehensive income (loss) for the three and six months ended June 30, 2017 and 2016 (in thousands): Derivatives in Cash Flow Hedging Relationship Gain (loss) recognized in OCI on derivatives (effective portion) Three Months Ended Six Months Ended June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest rate swaps $ (1,301 ) $ (2,532 ) $ 768 $ (15,412 ) Amount reclassified from OCI into income (effective portion) Three Months Ended Six Months Ended Location June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest expense (1) $ 953 $ 1,707 $ 2,199 $ 3,429 ______________ (1) Increases in fair value as a result of accrued interest associated with our swap transactions are recorded in accumulated OCI and subsequently reclassified into income. Such amounts are shown net in the statements of changes in equity and offset dollar for dollar. Amount recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing) Three Months Ended Six Months Ended Location June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest expense (1) $ (29 ) $ 1,941 $ 1 $ 1,941 _____________ (1) Represents the portion of the change in fair value of our interest rate swaps as (income) or expense attributable to the mismatch between an interest rate floor on our hedged debt and no floor on the index rate in our interest rate swaps which causes hedge ineffectiveness. Amounts reported in accumulated OCI related to derivatives will be reclassified to interest expense as interest payments and accruals are made on our variable-rate debt. During the next twelve months, we estimate that approximately $1.9 million will be reclassified as an increase to interest expense. We have agreements with our derivative counterparties that contain provisions where if we default on any of our indebtedness for at least 30 days, during which time such default has not been remedied, and in all cases provided that the aggregate amount of all such defaults is not less than $10.0 million for recourse debt or $75.0 million for non-recourse debt, then we could also be declared in default on our derivative obligations. As of June 30, 2017 , we had not been declared in default on any of our derivative obligations. As of June 30, 2017 , the fair value of our derivatives in a net liability position, which includes accrued interest but excludes any adjustment for nonperformance risk related to these agreements, was approximately $0.7 million . As of June 30, 2017 , we have not posted any collateral related to these agreements. If we had breached any of these provisions at June 30, 2017 , we could have been required to settle our obligations under the agreements at the termination value of approximately $0.7 million .

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies As of June 30, 2017 , we had commitments of approximately $21.5 million for future tenant improvements and leasing commissions. We have employment agreements with five of our executive officers. The term of each employment agreement ends on February 10, 2020, provided that the term will automatically continue for an additional one -year period unless either party provides 60 days written notice of non-renewal prior to the expiration of the initial term. The agreements provide for lump sum payments and an immediate lapse of restrictions on compensation received under the long-term incentive plan upon termination of employment without cause. As a result, in the event we terminated all of these agreements without cause as of June 30, 2017 , we would have recognized approximately $13.8 million in related compensation expense.

Equity

Equity	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Equity	Equity Series A Convertible Preferred Stock As of December 31, 2015, we had 10,000 shares of Series A participating, voting, convertible preferred stock (the “Series A Convertible Preferred Stock”) outstanding. In connection with the listing of our common stock on the NYSE on July 23, 2015, an automatic conversion of the Series A Convertible Preferred Stock was triggered with the number of shares to be issued not determinable until March 2, 2016, based on the Conversion Company Value, as defined in the Articles Supplementary. On March 2, 2016, based on the Conversion Company Value, no shares of common stock were issued, and the shares of Series A Convertible Preferred Stock were canceled. Stock Plans Our 2015 Equity Incentive Plan allows for, and our 2005 Incentive Award Plan allowed for, equity-based incentive awards to be granted to our employees, non-employee directors, and key persons as detailed below: Stock options. As of June 30, 2017 , we had no outstanding stock options. As of June 30, 2016, we had outstanding options held by our independent directors to purchase 12,495 shares of our common stock at a weighted average exercise price of approximately $40.13 per share. Restricted stock units. We have outstanding restricted stock units (“RSUs”) held by our independent directors. These units vest 13 months after the grant date. Subsequent to vesting, the restricted stock units will be converted to an equivalent number of shares of common stock upon the earlier to occur of the following events or dates: (i) separation from service for any reason other than cause; (ii) a change in control of the Company; (iii) death; or (iv) specific dates chosen by the independent directors that range from July 2017 to June 2018. Expense is measured at the grant date based on the estimated fair value of the award and is recognized over the vesting period. Any forfeitures of awards are recognized as they occur. The following is a summary of the number of outstanding RSUs held by our independent directors as of June 30, 2017 and 2016 : June 30, 2017 June 30, 2016 Units Weighted Average Price per unit Units Weighted Average Price per unit Outstanding at the beginning of the year 39,255 $ 16.45 28,705 $ 18.29 Issued 19,672 $ 17.03 18,275 $ 15.05 Converted (29,307 ) $ 16.92 (7,725 ) $ 19.96 Outstanding at the end of the period (1) 29,620 $ 16.38 39,255 $ 16.45 _____________ (1) As of June 30, 2017 , none of the RSUs held by our independent directors are vested. In 2016, 111,063 RSUs were issued to employees with a grant price of $15.26 per unit. During the six months ended June 30, 2017 , 97,557 RSUs were issued to employees with a weighted average grant price of $18.10 per unit. These units vest on December 31, 2018 and December 31, 2019, respectively, at which time they will be converted into a number of shares of common stock, which could range from zero shares to 222,126 shares at December 31, 2018, and zero shares to 195,114 shares at December 31, 2019. The actual number of shares of common stock issued will be based on our annualized total stockholder return (“TSR”) percentage as compared to three metrics: our TSR on a predetermined absolute basis, the TSR of the constituent companies of the NAREIT Office Index (unweighted), and the TSR of a select group of peer companies. Expense is measured at the grant date, based on the estimated fair value of the award ( $19.18 per unit for the 2016 grants and $20.95 per unit for the 2017 grants) as determined by a Monte Carlo simulation-based model using the assumptions outlined in the table below. Any forfeitures of awards are recognized as they occur. Assumption Value Expected volatility 24%-26% Risk-free interest rate 1.15%-1.53% Expected term 35 months Expected dividend yield 3.7%-4.5% Restricted stock. We have outstanding restricted stock held by employees. Restrictions on outstanding shares lapse based on various lapse schedules and range from December 2017 to May 2020. Compensation cost is measured at the grant date based on the estimated fair value of the award and is recognized as expense over the service period based on a tiered lapse schedule. Any forfeitures of awards are recognized as they occur. The following is a summary of the number of shares of restricted stock outstanding as of June 30, 2017 and 2016 : June 30, 2017 June 30, 2016 Shares Weighted Average Price per share Shares Weighted Average Price per share Outstanding at the beginning of the year 246,805 $ 20.74 281,905 $ 22.46 Issued 121,860 $ 17.88 119,523 $ 15.19 Forfeiture (20,089 ) $ 17.53 (8,406 ) $ 19.98 Restrictions lapsed (57,553 ) $ 25.64 (59,673 ) $ 25.64 Outstanding at the end of the period 291,023 $ 18.79 333,349 $ 19.34 For the three months ended June 30, 2017 and 2016 , we recognized a total of approximately $1.0 million and $1.1 million , respectively, for compensation expense related to the amortization of all of the equity-based incentive awards outlined above. For the six months ended June 30, 2017 and 2016 , we recognized a total of approximately $1.9 million and $2.0 million , respectively, for compensation expense related to the amortization of all of the equity-based incentive awards outlined above. As of June 30, 2017 , the total remaining compensation cost on unvested awards was approximately $5.7 million , with a weighted average remaining contractual life of approximately 1.5 years.

Net Income (Loss) per Common Sh

Net Income (Loss) per Common Share	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Net Income (Loss) per Common Share	Net Income (Loss) per Common Share Net income (loss) per common share is calculated using the two-class method, which requires the allocation of undistributed net income between common and participating stockholders. All outstanding restricted stock awards containing rights to non-forfeitable distributions are considered participating securities for this calculation. In periods of net loss, no loss is allocated to participating securities because our participating securities do not have a contractual obligation to share in our losses. The following table reflects the calculation of basic and diluted net income (loss) per common share for the three and six months ended June 30, 2017 and 2016 (in thousands, except per share data). Three Months Ended Six Months Ended June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Numerator: Net income (loss) attributable to common stockholders $ 4,031 $ (9,352 ) $ 102,202 $ (22,059 ) Less: net income allocated to participating securities — — (611 ) — Numerator for basic net income (loss) per share $ 4,031 $ (9,352 ) $ 101,591 $ (22,059 ) Add: undistributed net income allocated to participating securities — — 506 — Less: undistributed net income re-allocated to participating securities — — (504 ) — Numerator for diluted net income (loss) per share (1) $ 4,031 $ (9,352 ) $ 101,593 $ (22,059 ) Denominator: Weighted average common shares outstanding - basic 47,536 47,406 47,524 47,398 Effect of dilutive securities 339 — 204 — Weighted average common shares outstanding - diluted 47,875 47,406 47,728 47,398 Basic net income (loss) per common share $ 0.08 $ (0.20 ) $ 2.14 $ (0.47 ) Diluted net income (loss) per common share $ 0.08 $ (0.20 ) $ 2.13 $ (0.47 ) Securities excluded from weighted average common shares outstanding-diluted because their effect would be anti-dilutive 29 464 29 417 _______________ (1) In periods where there is no undistributed net income to allocate to participating securities, the treasury stock method is used to calculate dilutive securities.

Supplemental Cash Flow Informat

Supplemental Cash Flow Information	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Supplemental Cash Flow Information	Supplemental Cash Flow Information Supplemental cash flow information is summarized below for the six months ended June 30, 2017 and 2016 (in thousands): Six Months Ended June 30, 2017 June 30, 2016 Interest paid, net of amounts capitalized $ 12,695 $ 19,742 Income taxes paid $ 403 $ 1,964 Non-cash investing activities: Property and equipment additions in accounts payable and accrued liabilities $ 7,816 $ 12,016 Liabilities assumed through the purchase of real estate $ 3,267 $ — Escrow deposit applied to purchase of real estate $ 14,000 $ — Sale of real estate and lease intangibles to unconsolidated joint venture $ 13,804 $ — Acquisition of controlling interest in unconsolidated entity $ 9,770 $ — Non-cash financing activities: Cancellation of Series A Convertible Preferred Stock $ — $ 2,700 Mortgage notes assumed (1) $ 146,000 $ — Unrealized gain on interest rate derivatives $ 768 $ — Unrealized loss on interest rate derivatives $ — $ 15,412 Accrual for distributions declared $ — $ 8,602 _________________ (1) The approximately $146.0 million mortgage notes assumed during the six months ended June 30, 2017 , includes approximately $66.0 million of debt assumed when we acquired Legacy District One, approximately $40.1 million of debt assumed when we acquired the remaining 50.16% interest in our Domain 2 and Domain 7 properties, and approximately $39.9 million of debt associated with our previously held 49.84% unconsolidated interest in the Domain 2 and Domain 7 properties. Domain 2 and Domain 7 were consolidated during the six months ended June 30, 2017 .

Basis of Presentation and Sig21

Basis of Presentation and Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Real Estate	We amortize the value of in-place leases, in-place tenant improvements, and in-place leasing commissions to expense over the initial term of the respective leases. The tenant relationship values are amortized to expense over the tenants’ respective initial lease terms and any anticipated renewal periods, but in no event does the amortization period for intangible assets or liabilities exceed the remaining depreciable life of the building. Should a tenant terminate its lease, the unamortized portion of the acquired lease intangibles related to that tenant would be charged to expense. The estimated remaining average useful lives for acquired lease intangibles range from an ending date of July 2017 to an ending date of June 2027.
Impairment of Real Estate Related Assets	Impairment of Real Estate-Related Assets For our consolidated real estate assets, we monitor events and changes in circumstances indicating that the carrying amounts of the real estate assets may not be recoverable. When such events or changes in circumstances are present, we assess potential impairment by comparing estimated future undiscounted cash flows expected to be generated over the life of the asset including its eventual disposition, to the carrying amount of the asset. In the event that the carrying amount exceeds the estimated future undiscounted cash flows and also exceeds the fair value of the asset, we recognize an impairment loss to adjust the carrying amount of the asset to its estimated fair value. Our process to estimate the fair value of an asset involves using bona fide purchase offers or the expected sales price of an executed sales agreement, which would be considered Level 1 or Level 2 assumptions within the fair value hierarchy. To the extent that this type of third-party information is unavailable, we estimate projected cash flows and a risk-adjusted rate of return that we believe would be used by a third party market participant in estimating the fair value of an asset. This is considered a Level 3 assumption within the fair value hierarchy. These projected cash flows are prepared internally by the Company’s asset management professionals and are updated quarterly to reflect in-place and projected leasing activity, market revenue and expense growth rates, market capitalization rates, discount rates, and changes in economic and other relevant conditions. The Company’s Chief Financial Officer, Senior Vice President - Accounting, and Managing Director - Asset Management review these projected cash flows to assure that the valuation is prepared using reasonable inputs and assumptions which are consistent with market data or with assumptions that would be used by a third party market participant and assume the highest and best use of the real estate investment. We had no impairment charges for the six months ended June 30, 2017 . For the six months ended June 30, 2016 , we recorded a non-cash impairment charge totaling approximately $4.8 million related to the impairment of a consolidated real estate asset assessed for impairment due to a change in management’s estimate of the intended hold period. For our unconsolidated real estate assets, at each reporting date we compare the estimated fair value of our investment to the carrying amount. An impairment charge is recorded to the extent the fair value of our investment is less than the carrying amount and the decline in value is determined to be other than a temporary decline. We had no impairment charges related to our investments in unconsolidated entities for the six months ended June 30, 2017 and 2016 . In evaluating our investments for impairment, management makes several estimates and assumptions, including, but not limited to, the projected date of disposition (the intended hold period) and sales price for each property, the estimated future cash flows of each property during our estimated ownership period, and for unconsolidated investments, the estimated future distributions from the investment. A change in these estimates and assumptions could result in understating or overstating the carrying amount of our investments which could be material to our financial statements. We undergo continuous evaluations of property level performance, credit market conditions, and financing options. If our assumptions regarding the cash flows expected to result from the use and eventual disposition of our properties decrease or our expected hold periods decrease, we may incur future impairment charges on our real estate-related assets. In addition, we may incur impairment charges on assets classified as held for sale in the future if the carrying amount of the asset upon classification as held for sale exceeds the estimated fair value, less costs to sell.
Cash and Cash Equivalents and Restricted Cash	Cash, Cash Equivalents, and Restricted Cash We consider investments in highly-liquid money market funds or investments with original maturities of three months or less to be cash equivalents. Restricted cash includes restricted money market accounts, as required by our lenders or by leases, for anticipated tenant improvements, property taxes and insurance, certain tenant security deposits, and additional loan security reserves.
Accounts Receivable, net	Our allowance for doubtful accounts is an estimate based on management’s evaluation of accounts where it has determined that a tenant may not meet its financial obligations. In these situations, management uses its judgment, based on the facts and circumstances, and records a reserve for that tenant against amounts due to reduce the receivable to an amount it believes is collectible. These reserves are reevaluated and adjusted as additional information becomes available.
Investments in Unconsolidated Entities	Investments in Unconsolidated Entities Investments in unconsolidated entities consist of our noncontrolling interests in properties. We account for these investments using the equity method of accounting in accordance with GAAP. We use the equity method of accounting when we have significant influence, but not control, of the operating and financial decisions of these investments and thereby have some responsibility to create a return on our investment. The equity method of accounting requires these investments to be initially recorded at cost and subsequently increased (decreased) for our share of net income (loss), including eliminations for our share of inter-company transactions, and increased (decreased) for contributions (distributions). To the extent that we contribute assets to an unconsolidated entity, our investment in the unconsolidated entity is recorded at our cost basis in the assets that were contributed to the entity. To the extent that our cost basis is different than the basis reflected at the entity level, the basis difference is generally amortized over the life of the related asset and included in our share of equity in operations of investments. For unconsolidated investments that have properties under development, we capitalize interest expense to our investment basis using our weighted average interest rate of consolidated debt. Capitalization begins when we are engaged in the activities necessary to get the property ready for its intended use. We cease capitalization when the development is completed and ready for its intended use or if the intended use changes such that capitalization is no longer appropriate.
Other Intangible Assets, net	Other Intangible Assets, net Other intangible assets consist of below-market ground leases on properties where a third party owns and has leased the underlying land to us.
Revenue Recognition	Revenue Recognition We recognize rental income generated from all leases of consolidated real estate assets on a straight-line basis over the terms of the respective leases, including the effect of rent holidays, if any. The total net increase to rental revenue due to straight-line rent adjustments for the three months ended June 30, 2017 and 2016 , was approximately $2.0 million and $1.3 million , respectively. The total net increase to rental revenue due to straight-line rent adjustments for both the six months ended June 30, 2017 and 2016 , was approximately $3.8 million . When a tenant exceeds its tenant improvement allowance, this amount is reimbursed to us and recorded as a deferred rent liability, which is recognized as rental revenue over the life of the lease. The total net increase to rental revenue due to this deferred rent for the three months ended June 30, 2017 and 2016 , was approximately $0.4 million and $0.9 million , respectively. The total net increase to rental revenue due to this deferred rent for the six months ended June 30, 2017 and 2016 , was approximately $1.0 million and $1.9 million , respectively. Our rental revenue also includes amortization of acquired above- and below-market leases. The total net increase to rental revenue due to the amortization of acquired above- and below-market leases for the three months ended June 30, 2017 and 2016 , was approximately $0.9 million and $1.1 million , respectively. The total net increase to rental revenue due to the amortization of acquired above- and below-market leases for the six months ended June 30, 2017 and 2016 , was approximately $1.8 million and $2.5 million , respectively. Revenues relating to lease termination fees are recognized on a straight-line basis amortized from the time that a tenant’s right to occupy the leased space is modified through the end of the revised lease term. For the three months ended June 30, 2017 and 2016 , we recognized lease termination fees of approximately $0.1 million and $0.7 million , respectively. For the six months ended June 30, 2017 and 2016 , we recognized lease termination fees of approximately $0.2 million and $1.3 million , respectively.

Basis of Presentation and Sig22

Basis of Presentation and Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2017
Accounting Policies [Abstract]
Schedule of cost basis, accumulated depreciation and amortization related to entity's consolidated real estate properties and related lease intangibles	As of June 30, 2017 , and December 31, 2016 , the cost basis and accumulated depreciation and amortization related to our consolidated depreciable real estate properties and related lease intangibles were as follows (in thousands): Lease Intangibles Assets Liabilities Acquired Above-Market Leases Acquired Below-Market Leases Buildings and Improvements Other Lease Intangibles as of June 30, 2017 Cost $ 1,639,756 $ 154,395 $ 5,004 $ (52,142 ) Less: accumulated depreciation and amortization (494,260 ) (61,964 ) (4,345 ) 31,489 Net $ 1,145,496 $ 92,431 $ 659 $ (20,653 ) Lease Intangibles Assets Liabilities Acquired Above-Market Leases Acquired Below-Market Leases Buildings and Improvements Other Lease Intangibles as of December 31, 2016 Cost $ 1,579,157 $ 131,618 $ 5,005 $ (42,537 ) Less: accumulated depreciation and amortization (535,516 ) (70,672 ) (4,107 ) 35,651 Net $ 1,043,641 $ 60,946 $ 898 $ (6,886 )
Anticipated amortization associated with the acquired lease intangibles for each of the five years	Anticipated amortization associated with acquired lease intangibles for each of the following five years is as follows (in thousands): July 2017 - December 2017 $ 1,922 2018 $ 3,551 2019 $ 3,568 2020 $ 3,675 2021 $ 3,340
Cash, cash equivalents and restricted cash	We early adopted new Financial Accounting Standards Board (“FASB”) guidance on December 31, 2016, which changes the presentation of our statements of cash flows and related disclosures for all periods presented, and accordingly, the following is a summary of our total cash, cash equivalents, and restricted cash as presented in our statements of cash flows for the six months ended June 30, 2017 and 2016 (in thousands): June 30, June 30, 2016 Cash and cash equivalents $ 28,763 $ 78,599 Restricted cash 10,953 10,778 Total cash, cash equivalents, and restricted cash $ 39,716 $ 89,377
Cash, cash equivalents and restricted cash	We early adopted new Financial Accounting Standards Board (“FASB”) guidance on December 31, 2016, which changes the presentation of our statements of cash flows and related disclosures for all periods presented, and accordingly, the following is a summary of our total cash, cash equivalents, and restricted cash as presented in our statements of cash flows for the six months ended June 30, 2017 and 2016 (in thousands): June 30, June 30, 2016 Cash and cash equivalents $ 28,763 $ 78,599 Restricted cash 10,953 10,778 Total cash, cash equivalents, and restricted cash $ 39,716 $ 89,377
Summary of net accounts receivable	The following is a summary of our accounts receivable as of June 30, 2017 , and December 31, 2016 (in thousands): June 30, December 31, Straight-line rental revenue receivable $ 58,231 $ 68,287 Tenant receivables 3,544 5,047 Non-tenant receivables 1,437 691 Allowance for doubtful accounts (799 ) (2,566 ) Total $ 62,413 $ 71,459
Schedule of other intangible assets	As of June 30, 2017 , and December 31, 2016 , the cost basis and accumulated amortization related to our consolidated other intangible assets were as follows (in thousands): June 30, December 31, Cost $ 2,978 $ 11,277 Less: accumulated amortization (1,132 ) (1,490 ) Net $ 1,846 $ 9,787

Real Estate Activities (Tables)

Real Estate Activities (Tables)	6 Months Ended
	Jun. 30, 2017
Real Estate Activities [Abstract]
Sale of Real Estate	The following table presents our sales of real estate for the six months ended June 30, 2017 (in thousands): Property Name Date of Sale Location Rentable Square Footage Contract Sale Price Proceeds from Sale Buena Vista Plaza 01/18/17 Burbank, CA 115 $ 52,500 $ 47,498 Three Parkway 03/01/17 Philadelphia, PA 561 95,000 91,876 Eisenhower I (1) 03/13/17 Tampa, FL 130 31,400 30,742 Third + Shoal (2) 03/31/17 Austin, TX N/A 14,955 14,525 Louisville Portfolio (3) 06/26/17 Louisville, KY 678 71,500 68,626 1,484 $ 265,355 $ 253,267 __________________ (1) We may be entitled to receive an additional $3.0 million subject to certain future events. (2) We sold a 50% interest in our 95% interest in the Third + Shoal development property. (3) The Louisville Portfolio consists of five properties located in Louisville, Kentucky.
Schedule of assets and liabilities associated with real estate held for sale	The major classes of assets and obligations associated with real estate held for sale as of December 31, 2016, were as follows (in thousands): December 31, 2016 Land $ 5,481 Buildings and improvements, net of approximately $11.8 million in accumulated depreciation 24,837 Accounts receivable and other assets 665 Lease intangibles, net of approximately $2.1 million in accumulated amortization 1,363 Assets associated with real estate held for sale $ 32,346 Acquired below-market leases, net of approximately $0.2 million in accumulated amortization $ 44 Other liabilities 899 Obligations associated with real estate held for sale $ 943

Investments in Unconsolidated24

Investments in Unconsolidated Entities (Tables)	6 Months Ended
	Jun. 30, 2017
Equity Method Investments and Joint Ventures [Abstract]
Summary of the entity's investments in unconsolidated entities	The following is a summary of our investments in unconsolidated entities as of June 30, 2017 , and December 31, 2016 (dollar amounts in thousands): Ownership Interest Unconsolidated Investment Balance Entity Name Property June 30, December 31, 2016 June 30, December 31, Domain Junction LLC (1) Domain 2 & Domain 7 100.00 % 49.84 % $ — $ 9,770 Domain Junction 8 Venture LLC (2)(3) Domain 8 50.00 % 50.00 % 1,469 18,093 TR 208 Nueces Member, LLC (4) Third + Shoal 47.50 % 95.00 % 24,061 — COLDC 54 Holdings, LLC (3)(5) Colorado Building — 10.00 % — 711 GSTDC 72 Holdings, LLC (3)(5) 1325 G Street — 10.00 % — 3,719 1301 Chestnut Associates, L.P. (6) Wanamaker Building 1.10 % 60.00 % — 44,520 Total (7) ` $ 25,530 $ 76,813 _________________ (1) On January 4, 2017, we acquired our unrelated third party’s 50.16% interest in Domain Junction LLC increasing our ownership interest to 100% , and these properties were consolidated. (2) All major decisions for this entity are made by the other owner. (3) We have evaluated our investments in unconsolidated entities in order to determine if they are VIEs. Based on our assessment, we have identified each of these entities as a VIE, but we are not the primary beneficiary, as we do not have the power to direct the activities that most significantly impact the economic performance of these entities. For these VIEs in which we are not deemed to be the primary beneficiary, we continue to account for them using the equity method. The maximum amount of exposure to loss with respect to these VIEs is the carrying amount of our investment. At June 30, 2017 , these VIEs have total assets of approximately $84.9 million and total liabilities of approximately $90.6 million . At December 31, 2016 , our VIEs had total assets of approximately $353.5 million and total liabilities of approximately $262.8 million . (4) On March 31, 2017, we sold a 50% interest in the entity that owns a 95% interest in Third + Shoal, resulting in this property being deconsolidated as control of this property is now shared. (5) On April 27, 2017, the Colorado Building and 1325 G Street were sold for a combined contract sales price of $259.0 million (at 100%). (6) On January 17, 2017, we sold substantially all of our noncontrolling investment in 1301 Chestnut Associates, L.P. At June 30, 2017 , our remaining 1.1% interest is accounted for using the cost method and is included in “prepaid expenses and other assets” on our condensed consolidated balance sheet. (7) Our investment in unconsolidated entities at June 30, 2017, and December 31, 2016, includes basis adjustments that total approximately $8.8 million and $7.2 million , respectively. These amounts represent the aggregate difference between our historical cost basis and our equity basis reflected at the joint venture level, which is typically amortized over the life of the related assets and liabilities. Basis differences occur from impairment of investments and upon the transfer of assets that were previously owned by us into a joint venture. In addition, certain acquisition, transaction, and other costs may not be reflected in the net assets at the joint venture level.

Notes Payable, net (Tables)

Notes Payable, net (Tables)	6 Months Ended
	Jun. 30, 2017
Debt Disclosure [Abstract]
Schedule of long-term debt maturities	The following table provides information regarding the timing of principal payments of our notes payable, net as of June 30, 2017 (in thousands): Principal payments due in: July 2017 - December 2017 $ 48,867 2018 21,501 2019 301,589 2020 1,670 2021 72,416 Thereafter 341,000 Less: unamortized debt issuance costs (1) (7,799 ) Notes payable, net $ 779,244 ________________ (1) Excludes approximately $2.1 million of unamortized debt issuance costs associated with the revolving line of credit because these costs are presented as an asset on our condensed consolidated balance sheets.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2017
Fair Value Disclosures [Abstract]
Schedule of financial assets and liabilities measured at fair value on a recurring basis	The following table sets forth our financial assets and liabilities measured at fair value on a recurring basis, which equals book value, by level within the fair value hierarchy as of June 30, 2017 , and December 31, 2016 (in thousands). Basis of Fair Value Measurements Quoted Prices In Active Markets for Identical Items (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Total Fair Value Description June 30, 2017 Derivative financial instruments: Assets $ 988 $ — $ 988 $ — Liabilities $ (691 ) $ — $ (691 ) $ — December 31, 2016 Derivative financial instruments: Assets $ 1,182 $ — $ 1,182 $ — Liabilities $ (1,652 ) $ — $ (1,652 ) $ —
Schedule of carrying amounts and related estimated fair value of notes payable	Carrying amounts of our notes payable and the related estimated fair value as of June 30, 2017 , and December 31, 2016 , are as follows (in thousands): June 30, 2017 December 31, 2016 Carrying Amount Fair Value Carrying Amount Fair Value Notes payable $ 787,043 $ 791,317 $ 834,131 $ 837,878 Less: unamortized debt issuance costs (7,799 ) (7,348 ) Notes payable, net $ 779,244 $ 826,783

Derivative Instruments and He27

Derivative Instruments and Hedging Activities (Tables)	6 Months Ended
	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The following table summarizes the notional values of our derivative financial instruments (in thousands) as of June 30, 2017 . The notional values provide an indication of the extent of our involvement in these instruments at June 30, 2017 , but do not represent exposure to credit, interest rate, or market risks. Type/Description Notional Value Index Strike Rate Effective Date Maturity Date Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.6775 % 12/31/14 10/31/19 Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.6935 % 04/30/15 10/31/19 Interest rate swap - cash flow hedge $ 125,000 one-month LIBOR 1.7615 % 06/30/15 05/31/22 Interest rate swap - cash flow hedge $ 150,000 one-month LIBOR 1.7695 % 06/30/15 05/31/22
Schedule of fair value of derivative financial instruments included in other liabilities	The table below presents the fair value of our derivative financial instruments, included in “prepaid expenses and other assets” and “other liabilities” on our condensed consolidated balance sheets, as of June 30, 2017 , and December 31, 2016 (in thousands): Derivatives designated as hedging instruments: Derivative Assets Derivative Liabilities June 30, December 31, June 30, December 31, Interest rate swaps $ 988 $ 1,182 $ (691 ) $ (1,652 )
Schedule of effect of the change in fair value of derivative financial instruments in statement of operations and comprehensive income (loss)	The tables below present the effect of the change in fair value of derivative financial instruments in our condensed consolidated statements of operations and comprehensive income (loss) for the three and six months ended June 30, 2017 and 2016 (in thousands): Derivatives in Cash Flow Hedging Relationship Gain (loss) recognized in OCI on derivatives (effective portion) Three Months Ended Six Months Ended June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest rate swaps $ (1,301 ) $ (2,532 ) $ 768 $ (15,412 ) Amount reclassified from OCI into income (effective portion) Three Months Ended Six Months Ended Location June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest expense (1) $ 953 $ 1,707 $ 2,199 $ 3,429 ______________ (1) Increases in fair value as a result of accrued interest associated with our swap transactions are recorded in accumulated OCI and subsequently reclassified into income. Such amounts are shown net in the statements of changes in equity and offset dollar for dollar. Amount recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing) Three Months Ended Six Months Ended Location June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Interest expense (1) $ (29 ) $ 1,941 $ 1 $ 1,941 _____________ (1) Represents the portion of the change in fair value of our interest rate swaps as (income) or expense attributable to the mismatch between an interest rate floor on our hedged debt and no floor on the index rate in our interest rate swaps which causes hedge ineffectiveness.

Equity (Tables)

Equity (Tables)	6 Months Ended
	Jun. 30, 2017
Equity [Abstract]
Schedule of Restricted Stock Units	The following is a summary of the number of outstanding RSUs held by our independent directors as of June 30, 2017 and 2016 : June 30, 2017 June 30, 2016 Units Weighted Average Price per unit Units Weighted Average Price per unit Outstanding at the beginning of the year 39,255 $ 16.45 28,705 $ 18.29 Issued 19,672 $ 17.03 18,275 $ 15.05 Converted (29,307 ) $ 16.92 (7,725 ) $ 19.96 Outstanding at the end of the period (1) 29,620 $ 16.38 39,255 $ 16.45 _____________ (1) As of June 30, 2017 , none of the RSUs held by our independent directors are vested.
Summary of Restricted Stock Valuation Assumptions	Expense is measured at the grant date, based on the estimated fair value of the award ( $19.18 per unit for the 2016 grants and $20.95 per unit for the 2017 grants) as determined by a Monte Carlo simulation-based model using the assumptions outlined in the table below. Any forfeitures of awards are recognized as they occur. Assumption Value Expected volatility 24%-26% Risk-free interest rate 1.15%-1.53% Expected term 35 months Expected dividend yield 3.7%-4.5%
Summary of the Number of Shares of Restricted Stock Outstanding	The following is a summary of the number of shares of restricted stock outstanding as of June 30, 2017 and 2016 : June 30, 2017 June 30, 2016 Shares Weighted Average Price per share Shares Weighted Average Price per share Outstanding at the beginning of the year 246,805 $ 20.74 281,905 $ 22.46 Issued 121,860 $ 17.88 119,523 $ 15.19 Forfeiture (20,089 ) $ 17.53 (8,406 ) $ 19.98 Restrictions lapsed (57,553 ) $ 25.64 (59,673 ) $ 25.64 Outstanding at the end of the period 291,023 $ 18.79 333,349 $ 19.34

Net Income (Loss) per Common 29

Net Income (Loss) per Common Share (Tables)	6 Months Ended
	Jun. 30, 2017
Earnings Per Share [Abstract]
Basic and diluted net income (loss) per common share	The following table reflects the calculation of basic and diluted net income (loss) per common share for the three and six months ended June 30, 2017 and 2016 (in thousands, except per share data). Three Months Ended Six Months Ended June 30, 2017 June 30, 2016 June 30, 2017 June 30, 2016 Numerator: Net income (loss) attributable to common stockholders $ 4,031 $ (9,352 ) $ 102,202 $ (22,059 ) Less: net income allocated to participating securities — — (611 ) — Numerator for basic net income (loss) per share $ 4,031 $ (9,352 ) $ 101,591 $ (22,059 ) Add: undistributed net income allocated to participating securities — — 506 — Less: undistributed net income re-allocated to participating securities — — (504 ) — Numerator for diluted net income (loss) per share (1) $ 4,031 $ (9,352 ) $ 101,593 $ (22,059 ) Denominator: Weighted average common shares outstanding - basic 47,536 47,406 47,524 47,398 Effect of dilutive securities 339 — 204 — Weighted average common shares outstanding - diluted 47,875 47,406 47,728 47,398 Basic net income (loss) per common share $ 0.08 $ (0.20 ) $ 2.14 $ (0.47 ) Diluted net income (loss) per common share $ 0.08 $ (0.20 ) $ 2.13 $ (0.47 ) Securities excluded from weighted average common shares outstanding-diluted because their effect would be anti-dilutive 29 464 29 417 _______________ (1) In periods where there is no undistributed net income to allocate to participating securities, the treasury stock method is used to calculate dilutive securities.

Supplemental Cash Flow Inform30

Supplemental Cash Flow Information (Tables)	6 Months Ended
	Jun. 30, 2017
Supplemental Cash Flow Elements [Abstract]
Schedule of supplemental cash flow information	Supplemental cash flow information is summarized below for the six months ended June 30, 2017 and 2016 (in thousands): Six Months Ended June 30, 2017 June 30, 2016 Interest paid, net of amounts capitalized $ 12,695 $ 19,742 Income taxes paid $ 403 $ 1,964 Non-cash investing activities: Property and equipment additions in accounts payable and accrued liabilities $ 7,816 $ 12,016 Liabilities assumed through the purchase of real estate $ 3,267 $ — Escrow deposit applied to purchase of real estate $ 14,000 $ — Sale of real estate and lease intangibles to unconsolidated joint venture $ 13,804 $ — Acquisition of controlling interest in unconsolidated entity $ 9,770 $ — Non-cash financing activities: Cancellation of Series A Convertible Preferred Stock $ — $ 2,700 Mortgage notes assumed (1) $ 146,000 $ — Unrealized gain on interest rate derivatives $ 768 $ — Unrealized loss on interest rate derivatives $ — $ 15,412 Accrual for distributions declared $ — $ 8,602 _________________ (1) The approximately $146.0 million mortgage notes assumed during the six months ended June 30, 2017 , includes approximately $66.0 million of debt assumed when we acquired Legacy District One, approximately $40.1 million of debt assumed when we acquired the remaining 50.16% interest in our Domain 2 and Domain 7 properties, and approximately $39.9 million of debt associated with our previously held 49.84% unconsolidated interest in the Domain 2 and Domain 7 properties. Domain 2 and Domain 7 were consolidated during the six months ended June 30, 2017 .

Business (Details)

Business (Details)	Jun. 30, 2017propertymarket
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of operating office properties	19
Number of non-operating properties	1
Number of development properties	3
Number of markets in which the entity owns interests in properties | market	8

Basis of Presentation and Sig32

Basis of Presentation and Significant Accounting Policies (Real Estate) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Real estate properties
Net	$ 1,145,496	$ 1,043,641
Intangible assets
Net	93,090	61,844
Intangible liabilities
Net	(20,653)	(6,886)
Other Lease Intangibles
Intangible assets
Cost	154,395	131,618
Less: accumulated depreciation and amortization	(61,964)	(70,672)
Net	92,431	60,946
Acquired Above-Market Leases
Intangible assets
Cost	5,004	5,005
Less: accumulated depreciation and amortization	(4,345)	(4,107)
Net	659	898
Acquired Below-Market Leases
Intangible liabilities
Cost	(52,142)	(42,537)
Less: accumulated depreciation and amortization	31,489	35,651
Net	(20,653)	(6,886)
Anticipated amortization associated with acquired lease intangibles
Anticipated Amortization Associated with the Acquired Lease Intangibles for Each of the Following Five Years
July 2017 - December 2017	1,922
2,018	3,551
2,019	3,568
2,020	3,675
2,021	3,340
Buildings and Improvements
Real estate properties
Cost	1,639,756	1,579,157
Less: accumulated depreciation and amortization	(494,260)	(535,516)
Net	$ 1,145,496	$ 1,043,641

Basis of Presentation and Sig33

Basis of Presentation and Significant Accounting Policies (Impairment of Real Estate Related Assets) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Impaired Long-Lived Assets Held and Used [Line Items]
Non-cash impairment charges	$ 0	$ 4,826,000
Unconsolidated entities
Impaired Long-Lived Assets Held and Used [Line Items]
Non-cash impairment charges	$ 0	$ 0

Basis of Presentation and Sig34

Basis of Presentation and Significant Accounting Policies Basis of Presentation and Significant Accounting Policies (Cash, Cash Equivalents, and Restricted Cash) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Accounting Policies [Abstract]
Cash and cash equivalents	$ 28,763	$ 14,884	$ 78,599
Restricted cash	10,953	7,509	10,778
Total cash, cash equivalents, and restricted cash	$ 39,716	$ 22,393	$ 89,377	$ 22,960

Basis of Presentation and Sig35

Basis of Presentation and Significant Accounting Policies (Accounts Receivable, net) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Accounts Receivable, Net [Abstract]
Straight-line rental revenue receivable	$ 58,231	$ 68,287
Tenant receivables	3,544	5,047
Non-tenant receivables	1,437	691
Allowance for doubtful accounts	(799)	(2,566)
Total	$ 62,413	$ 71,459

Basis of Presentation and Sig36

Basis of Presentation and Significant Accounting Policies (Other Intangible Assets, net) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Other Intangible Assets, Net [Abstract]
Cost	$ 2,978	$ 11,277
Less: accumulated amortization	(1,132)	(1,490)
Net	$ 1,846	$ 9,787

Basis of Presentation and Sig37

Basis of Presentation and Significant Accounting Policies (Revenue Recognition) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue Recognition [Abstract]
Net increase in rental revenues due to straight-line rent adjustments	$ 2,000	$ 1,300	$ 3,800	$ 3,800
Deferred Revenue, Revenue Recognized	400	900	1,000	1,900
Net increase in rental revenue due to amortization of above- and below-market leases	900	1,100	1,788	2,463
Lease termination fee revenue	$ 100	$ 700	$ 200	$ 1,300

Basis of Presentation and Sig38

Basis of Presentation and Significant Accounting Policies (Investments in Unconsolidated Entities) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Investments in Unconsolidated Entities [Line Items]
Interest costs capitalized	$ 0.6	$ 0.1
Unconsolidated Entity
Investments in Unconsolidated Entities [Line Items]
Interest costs capitalized	$ 0.7	$ 0.3

New Accounting Pronouncements -

New Accounting Pronouncements - Additional Information (Details) - Retained earnings - USD ($) $ in Thousands	Jan. 01, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect adjustment		$ (290)
Accounting Standards Update 2016-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect adjustment	$ 300

Real Estate Activities (Sales o

Real Estate Activities (Sales of Real Estate and Real Estate Held for Sale) (Details) ft² in Thousands, $ in Thousands

Aug. 08, 2017USD ($)

Jun. 26, 2017USD ($)ft²property

Mar. 31, 2017USD ($)

Mar. 13, 2017USD ($)ft²

Mar. 01, 2017USD ($)ft²

Jan. 18, 2017USD ($)ft²

Jun. 30, 2017USD ($)ft²property

Jun. 30, 2016USD ($)

Jun. 30, 2017USD ($)ft²property

Jun. 30, 2016USD ($)

Mar. 30, 2017

Dec. 31, 2016property

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Proceeds from sale

$ 330,045

$ 250,319

Number of operating office properties | property

19

19

Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Rentable square feet | ft²

1,484

1,484

Contract sale price

$ 265,355

$ 265,355

Proceeds from sale

253,267

Contribution to net income (loss)

$ 1,000

$ (500)

$ 2,500

$ (5,400)

Buena Vista Plaza Burbank Ca | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Rentable square feet | ft²

115

Contract sale price

$ 52,500

Proceeds from sale

$ 47,498

Three Parkway | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Rentable square feet | ft²

561

Contract sale price

$ 95,000

Proceeds from sale

$ 91,876

Eisenhower I | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Rentable square feet | ft²

130

Contract sale price

$ 31,400

Proceeds from sale

$ 30,742

Third Shoal | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Contract sale price

$ 14,955

Proceeds from sale

$ 14,525

Ownership Interest

47.50%

47.50%

95.00%

Louisville Property Portfolio | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Rentable square feet | ft²

678

Contract sale price

$ 71,500

Proceeds from sale

$ 68,626

Number of operating office properties | property

5

Assets held-for-sale

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Number of operating office properties | property

0

0

4

Scenario, forecast | Eisenhower I | Not discontinued operations

Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]

Proceeds from sale

$ 3,000

Real Estate Activities (Acquisi

Real Estate Activities (Acquisitions of Real Estate) (Details) ft² in Thousands, $ in Thousands	Jun. 23, 2017USD ($)ft²	Jan. 04, 2017USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jun. 30, 2017USD ($)	Jun. 30, 2016USD ($)	Jan. 05, 2017	Jan. 03, 2017	Dec. 31, 2016USD ($)
Business Acquisition [Line Items]
Gain on remeasurement of investment in unconsolidated entities			$ 0	$ 0	$ 14,168	$ 0
Lease intangibles, net			93,090		93,090				$ 61,844
Acquired below-market leases, net			$ 20,653		$ 20,653				$ 6,886
Domain 2 & Domain 7
Business Acquisition [Line Items]
Ownership Interest		50.16%	100.00%		100.00%		100.00%	49.84%	49.84%
Contract purchase price		$ 51,200
Acquisition, debt assumed		40,100
Gain on remeasurement of investment in unconsolidated entities		14,200
Lease intangibles, net		16,600
Acquired below-market leases, net		$ 9,400
Legacy District One
Business Acquisition [Line Items]
Contract purchase price	$ 123,300
Acquisition, debt assumed	66,000
Lease intangibles, net	20,000
Acquired below-market leases, net	$ 6,400
Rentable square feet | ft²	319
Stated annual interest rate	4.24%

Real Estate Activities (Real Es

Real Estate Activities (Real Estate Held for Sale) (Details) $ in Thousands	Jun. 30, 2017USD ($)property	Dec. 31, 2016USD ($)property
Real Estate Properties [Line Items]
Number of operating office properties | property	19
Long lived assets held for sale [Abstract]
Land	$ 141,010	$ 143,537
Buildings and improvements, net	1,145,496	1,043,641
Lease intangibles, net	93,090	61,844
Assets associated with real estate held for sale	0	32,346
Acquired below-market leases, net	20,653	6,886
Obligations associated with real estate held for sale	$ 0	$ 943
Assets held-for-sale
Real Estate Properties [Line Items]
Number of operating office properties | property	0	4
Long lived assets held for sale [Abstract]
Land		$ 5,481
Buildings and improvements, net		24,837
Buildings and improvements, accumulated depreciation		11,800
Accounts receivable and other assets		665
Lease intangibles, net		1,363
Lease intangibles, accumulated amortization		2,100
Assets associated with real estate held for sale		32,346
Acquired below-market leases, net		44
Acquired below-market leases, accumulated depreciation		200
Other liabilities		899
Obligations associated with real estate held for sale		$ 943

Real Estate Under Development (

Real Estate Under Development (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Real Estate Under Development [Abstract]
Development costs capitalized	$ 8.9	$ 3.8
Interest costs capitalized	$ 0.6	$ 0.1

Investments in Unconsolidated44

Investments in Unconsolidated Entities (Summary of Investments) (Details) - USD ($) $ in Thousands	Apr. 27, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Mar. 30, 2017	Jan. 05, 2017	Jan. 04, 2017	Jan. 03, 2017
Investments in Unconsolidated Entities [Line Items]
Unconsolidated Investment Balance		$ 25,530		$ 25,530		$ 76,813
Real estate investment, basis adjustment				8,800		$ 7,200
Equity in operations of investments		$ 6,556	$ 823	$ 6,300	$ 1,238
Domain 2 & Domain 7
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		100.00%		100.00%		49.84%		100.00%	50.16%	49.84%
Unconsolidated Investment Balance		$ 0		$ 0		$ 9,770
Total liabilities										$ 39,900
Domain 8
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		50.00%		50.00%		50.00%
Unconsolidated Investment Balance		$ 1,469		$ 1,469		$ 18,093
Third Shoal
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		47.50%		47.50%		95.00%
Unconsolidated Investment Balance		$ 24,061		$ 24,061		$ 0
Colorado Building
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		0.00%		0.00%		10.00%
Unconsolidated Investment Balance		$ 0		$ 0		$ 711
1325 G Street
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		0.00%		0.00%		10.00%
Unconsolidated Investment Balance		$ 0		$ 0		$ 3,719
Wanamaker Building
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		1.10%		1.10%		60.00%
Unconsolidated Investment Balance		$ 0		$ 0		$ 44,520
1325 G Street and Colorado Building
Investments in Unconsolidated Entities [Line Items]
Equity method investment, gain on sale of properties				6,700
Variable Interest Entity, not primary beneficiary
Investments in Unconsolidated Entities [Line Items]
Total assets		84,900		84,900		353,500
Total liabilities		$ 90,600		$ 90,600		$ 262,800
Third Shoal | Not discontinued operations
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		47.50%		47.50%			95.00%
Colorado Building and 1325 G Street | Not discontinued operations
Investments in Unconsolidated Entities [Line Items]
Contract sale price	$ 259,000
1301 Chestnut Associates, L.P. | Not discontinued operations
Investments in Unconsolidated Entities [Line Items]
Ownership Interest		1.10%		1.10%

Notes Payable, net (Narrative)

Notes Payable, net (Narrative) (Details) - USD ($)	6 Months Ended
	Jun. 30, 2017	Dec. 31, 2016
Line of Credit Facility [Line Items]
Notes payable, net	$ 779,244,000	$ 826,783,000
Notes payable, net secured by real estate assets	192,000,000
Carrying value of real estate securing notes payable	$ 256,100,000
Default interest rate	5.00%
Increase in interest expense for loans that are in default	$ 1,200,000
Line of credit, maximum borrowing capacity	$ 860,000,000
Revolving loan extension period	1 year
LIBOR interest index period one	1 month
LIBOR interest index period two	3 months
LIBOR Interest Index period three	6 months
Amount of borrowings with risk managed by hedged interest rates	$ 525,000,000
Available additional borrowings	$ 161,400,000
Weighted average interest rate for borrowings under the credit facility	3.23%
Minimum
Line of Credit Facility [Line Items]
Line of credit, applicable margin	0.35%
Maximum
Line of Credit Facility [Line Items]
Line of credit, applicable margin	2.50%
Notes payable
Line of Credit Facility [Line Items]
Notes payable, net	$ 779,244,000
Debt bearing interest at variable rates	$ 70,000,000
Weighted average interest rate for consolidated debt	3.74%
Effective average interest rate overall after effect of default interest	4.05%
Notes payable | Minimum
Line of Credit Facility [Line Items]
Stated annual interest rate	2.58%
Notes payable | Maximum
Line of Credit Facility [Line Items]
Stated annual interest rate	6.09%
Fifth Third Center - Columbus OH
Line of Credit Facility [Line Items]
Carrying value of real estate securing notes payable	$ 32,400,000
Outstanding balance of non-recourse property loan in default	48,200,000
Term loan facility
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	300,000,000
Second term loan facility
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	275,000,000
Revolving credit facility
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	285,000,000
Borrowings outstanding	20,000,000
Term loan facility and second term loan facility
Line of Credit Facility [Line Items]
Borrowings outstanding	$ 575,000,000
Federal Funds Effective Rate | Line of credit
Line of Credit Facility [Line Items]
Applicable margin	0.50%
Debt Instrument Variable Rate Base Libor | Line of credit
Line of Credit Facility [Line Items]
Applicable margin	1.00%

Notes Payable, net (Schedule of

Notes Payable, net (Schedule of Long-Term Debt Maturities) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Principal payments due in:
Notes payable, net	$ 779,244	$ 826,783
Deferred financing fees, net	2,089	$ 2,395
Notes payable
Principal payments due in:
July 2017 - December 2017	48,867
2,018	21,501
2,019	301,589
2,020	1,670
2,021	72,416
Thereafter	341,000
Less: unamortized debt issuance costs	(7,799)
Notes payable, net	779,244
Revolving credit facility
Principal payments due in:
Deferred financing fees, net	$ 2,100

Fair Value Measurements (Financ

Fair Value Measurements (Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Recurring basis - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Quoted Prices In Active Markets for Identical Items (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 0	$ 0
Liabilities	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	988	1,182
Liabilities	(691)	(1,652)
Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Liabilities	0	0
Total Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	988	1,182
Liabilities	$ (691)	$ (1,652)

Fair Value Measurement (Financi

Fair Value Measurement (Financial Instruments not Reported at Fair Value) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable, net	$ 779,244	$ 826,783
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	787,043	834,131
Less: unamortized debt issuance costs	(7,799)	(7,348)
Notes payable, net	779,244	826,783
Fair Value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes payable	$ 791,317	$ 837,878

Derivative Instruments and He49

Derivative Instruments and Hedging Activities (Notional Values of Derivative Financial Instruments) (Details) - USD ($)	Jun. 30, 2017	Jun. 30, 2015	Apr. 30, 2015	Dec. 31, 2014
Derivative [Line Items]
Notional Value	$ 525,000,000
Swap Number One
Derivative [Line Items]
Notional Value				$ 125,000,000
Strike Rate				1.6775%
Swap Number Two
Derivative [Line Items]
Notional Value			$ 125,000,000
Strike Rate			1.6935%
Swap Number Three
Derivative [Line Items]
Notional Value		$ 125,000,000
Strike Rate		1.7615%
Swap Number Four
Derivative [Line Items]
Notional Value		$ 150,000,000
Strike Rate		1.7695%

Derivative Instruments and He50

Derivative Instruments and Hedging Activities (Fair Value of Derivative Financial Instruments Included in Other Liabilities) (Details) - Designated as hedging instrument - Interest rate swaps - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Derivative Assets	$ 988	$ 1,182
Derivative Liabilities	$ (691)	$ (1,652)

Derivative Instruments and He51

Derivative Instruments and Hedging Activities (Derivatives in Cash Flow Hedging Relationship) (Details) - Cash flow hedging - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in OCI on derivative (effective portion)	$ (1,301)	$ (2,532)	$ 768	$ (15,412)
Interest expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount reclassified from OCI into income (effective portion)	953	1,707	2,199	3,429
Amount recognized in income on derivatives (ineffective portion and amount excluded from effectiveness testing)	$ (29)	$ 1,941	$ 1	$ 1,941

Derivative Instruments and He52

Derivative Instruments and Hedging Activities (Narrative) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017USD ($)
Debt Instrument, by Type [Line Items]
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	$ 1.9
Period over which default must be remedied	30 days
Derivative, net liability position, aggregate fair value	$ 0.7
Derivative, termination value	0.7
Recourse debt
Debt Instrument, by Type [Line Items]
Minimum amount of debt default that could cause derivative obligations to also be in default	10
Non-recourse debt
Debt Instrument, by Type [Line Items]
Minimum amount of debt default that could cause derivative obligations to also be in default	$ 75

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	6 Months Ended
	Jun. 30, 2017USD ($)executive
Commitments and contingencies
Number of executives | executive	5
Period of automatic continuation of term of employment	1 year
Notice period for non-renewal of term prior to the expiration of the initial term	60 days
Commitments for future tenant improvements and leasing commissions
Commitments and contingencies
Future tenant improvements and leasing commissions	$ 21.5
Employment agreements
Commitments and contingencies
Compensation expense if termination of employment without cause	$ 13.8

Equity (Series A Convertible Pr

Equity (Series A Convertible Preferred Stock) (Details) - shares	Mar. 02, 2016	Dec. 31, 2015
Subsidiary or Equity Method Investee [Line Items]
Common stock issued (in shares)	0
Behringer Harvard Reit I Services Holdings Llc
Subsidiary or Equity Method Investee [Line Items]
Series A participating, voting, and convertible preferred stock outstanding shares (in shares)		10,000

Equity (Stock Options) (Detail

Equity (Stock Options) (Details) - Independent Directors - Equity Option - $ / shares	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options (in shares)	0	12,495
Weighted average exercise price (in dollars per share)		$ 40.13

Equity (Restricted Stock Units)

Equity (Restricted Stock Units) (Details)	1 Months Ended		6 Months Ended		12 Months Ended
	Dec. 31, 2019shares	Dec. 31, 2018shares	Jun. 30, 2017Metric$ / sharesshares	Jun. 30, 2016$ / sharesshares	Dec. 31, 2016Metric$ / sharesshares
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Restricted stock units held by independent directors, vested (in units)			0
Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units, vesting period			13 months
Directors | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at the beginning of the year (in shares/units)			39,255	28,705	28,705
Issued (in units)			19,672	18,275
Converted (in units)			(29,307)	(7,725)
Outstanding at the end of the year (in shares/units)			29,620	39,255	39,255
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average price per unit, outstanding at the beginning of the year (in dollars per share/unit) | $ / shares			$ 16.45	$ 18.29	$ 18.29
Weighted average price per unit, issued (in dollars per unit) | $ / shares			17.03	15.05
Weighted average price per unit, converted (in dollars per unit) | $ / shares			16.92	19.96
Weighted average price per unit, outstanding at the end of the year (in dollars per share/unit) | $ / shares			$ 16.38	$ 16.45	$ 16.45
Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Issued (in units)			97,557		111,063
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average price per unit, issued (in dollars per unit) | $ / shares			$ 18.10		$ 15.26
Number of metrics used to compare annualized total stockholder return to | Metric			3		3
Estimated fair value of award determined by Monte Carlo model (in dollars per unit) | $ / shares			$ 20.95		$ 19.18
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected term			35 months
Minimum | Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected volatility			24.00%
Risk-free interest rate			1.15%
Expected dividend yield			3.70%
Maximum | Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Expected volatility			26.00%
Risk-free interest rate			1.53%
Expected dividend yield			4.50%
Scenario, forecast | Minimum | Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Number of common stock shares that restricted stock units can be converted to (in units)	0	0
Scenario, forecast | Maximum | Employee | Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Number of common stock shares that restricted stock units can be converted to (in units)	195,114	222,126

Equity (Restricted Stock) (Deta

Equity (Restricted Stock) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Compensation expense related to the amortization of all equity-based incentive awards	$ 1	$ 1.1	$ 1.9	$ 2
Total remaining compensation cost on unvested awards	$ 5.7		$ 5.7
Compensation cost not yet recognized, unvested awards, period for recognition			1 year 6 months
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at the beginning of the year (in shares/units)			246,805	281,905	281,905
Issued (in shares)			121,860	119,523
Forfeiture (in shares)			(20,089)	(8,406)
Restrictions lapsed (in units)			(57,553)	(59,673)
Outstanding at the end of the year (in shares/units)	291,023	333,349	291,023	333,349	246,805
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average price per unit, outstanding at the beginning of the year (in dollars per share/unit)			$ 20.74	$ 22.46	$ 22.46
Weighted average price per unit, issues (in dollars per share)			17.88	15.19
Weighted average price per unit, forfeited (in dollars per share)			17.53	19.98
Weighted average price per unit, restrictions lapsed (in dollars per share)			25.64	25.64
Weighted average price per unit, outstanding at the end of the year (in dollars per share/unit)	$ 18.79	$ 19.34	$ 18.79	$ 19.34	$ 20.74

Net Income (Loss) per Common 58

Net Income (Loss) per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator:
Net income (loss) attributable to common stockholders	$ 4,031	$ (9,352)	$ 102,202	$ (22,059)
Less: net income allocated to participating securities	0	0	(611)	0
Numerator for basic net income (loss) per share	4,031	(9,352)	101,591	(22,059)
Add: undistributed net income allocated to participating securities	0	0	506	0
Less: undistributed net income re-allocated to participating securities	0	0	(504)	0
Numerator for diluted net income (loss) per share (1)	$ 4,031	$ (9,352)	$ 101,593	$ (22,059)
Denominator:
Weighted average common shares outstanding - basic (in shares)	47,536,320	47,405,767	47,523,688	47,397,679
Effect of dilutive securities (in shares)	339,000	0	204,000	0
Weighted average common shares outstanding - diluted (in shares)	47,875,418	47,405,767	47,727,634	47,397,679
Basic income (loss) per common share (in dollars per share)	$ 0.08	$ (0.20)	$ 2.14	$ (0.47)
Diluted income (loss) per common share (in dollars per share)	$ 0.08	$ (0.20)	$ 2.13	$ (0.47)
Securities excluded from weighted average common shares outstanding-diluted because their effect would be anti-dilutive (in shares)	29,000	464,000	29,000	417,000

Supplemental Cash Flow Inform59

Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	Jun. 23, 2017	Jan. 04, 2017	Jun. 30, 2017	Jun. 30, 2016	Jan. 05, 2017	Jan. 03, 2017	Dec. 31, 2016
Supplemental Cash Flow Elements [Abstract]
Interest paid, net of amounts capitalized			$ 12,695	$ 19,742
Income taxes paid			403	1,964
Non-cash investing activities:
Property and equipment additions in accounts payable and accrued liabilities			7,816	12,016
Liabilities assumed through the purchase of real estate			3,267	0
Escrow deposit applied to purchase of real estate			14,000	0
Sale of real estate and lease intangibles to unconsolidated joint venture			13,804	0
Acquisition of controlling interest in unconsolidated entity			9,770	0
Non-cash financing activities:
Cancellation of Series A Convertible Preferred Stock			0	2,700
Mortgage notes assumed (1)			146,000	0
Unrealized gain on interest rate derivatives			768	0
Unrealized loss on interest rate derivatives			0	15,412
Accrual for distributions declared			$ 0	$ 8,602
Legacy District One
Noncash or Part Noncash Acquisitions [Line Items]
Acquisition, debt assumed	$ 66,000
Domain 2 & Domain 7
Noncash or Part Noncash Acquisitions [Line Items]
Acquisition, debt assumed		$ 40,100
Ownership Interest		50.16%	100.00%		100.00%	49.84%	49.84%
Real estate investment, debt						$ 39,900