STAG Industrial (STAG) 10-Q 3 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016
Document and Entity Information
Entity Registrant Name	STAG Industrial, Inc.
Entity Central Index Key	1,479,094
Document Type	10-Q
Document Period End Date	Mar. 31, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		68,186,375
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q1

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Rental Property:
Land	$ 229,288	$ 228,919
Buildings and improvements, net of accumulated depreciation of $160,820 and $150,395, respectively	1,328,602	1,332,298
Deferred leasing intangibles, net of accumulated amortization of $209,898 and $200,758, respectively	263,867	276,272
Total rental property, net	1,821,757	1,837,489
Cash and cash equivalents	15,469	12,011
Restricted cash	8,403	8,395
Tenant accounts receivable, net	22,425	21,478
Prepaid expenses and other assets	26,896	23,888
Interest rate swaps	0	1,867
Assets held for sale, net	2,996	0
Total assets	1,897,946	1,905,128
Liabilities:
Unsecured credit facility	6,000	56,000
Unsecured term loans	299,779	299,769
Unsecured notes	399,384	399,366
Mortgage notes	214,727	230,937
Accounts payable, accrued expenses and other liabilities	28,139	25,662
Interest rate swaps	13,732	3,766
Tenant prepaid rent and security deposits	13,318	14,628
Dividends and distributions payable	8,527	8,234
Deferred leasing intangibles, net of accumulated amortization of $8,514 and $8,536, respectively	10,830	11,387
Total liabilities	$ 994,436	$ 1,049,749
Commitments and contingencies
Equity:
Common stock, par value $0.01 per share, 150,000,000 shares authorized, 68,182,802 and 68,077,333 shares issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 682	$ 681
Additional paid-in capital	1,016,764	1,017,394
Common stock dividends in excess of earnings	(349,881)	(334,623)
Accumulated other comprehensive loss	(13,567)	(2,350)
Total stockholders’ equity	867,998	820,102
Noncontrolling interest	35,512	35,277
Total equity	903,510	855,379
Total liabilities and equity	1,897,946	1,905,128
Series A Preferred Stock
Equity:
Preferred stock	69,000	69,000
Series B Preferred Stock
Equity:
Preferred stock	70,000	70,000
Series C Preferred Stock
Equity:
Preferred stock	$ 75,000	$ 0

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Building and building, accumulated amortization	$ 160,820	$ 150,395
Deferred leasing intangibles assets, accumulated amortization	209,898	200,758
Deferred leasing intangibles liabilities, accumulated amortization	$ 8,514	$ 8,536
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	15,000,000	10,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	150,000,000	100,000,000
Common Stock, shares issued	68,182,802	68,077,333
Common stock, shares outstanding	68,182,802	68,077,333
Series A Preferred Stock
Preferred stock, shares issued	2,760,000	2,760,000
Preferred stock, shares outstanding	2,760,000	2,760,000
Preferred stock, liquidation preference (in dollars per share)	$ 25	$ 25
Series B Preferred Stock
Preferred stock, shares issued	2,800,000	2,800,000
Preferred stock, shares outstanding	2,800,000	2,800,000
Preferred stock, liquidation preference (in dollars per share)	$ 25	$ 25
Series C Preferred Stock
Preferred stock, shares issued	3,000,000
Preferred stock, shares outstanding	3,000,000
Preferred stock, liquidation preference (in dollars per share)	$ 25

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue
Rental income	$ 51,349	$ 43,249
Tenant recoveries	9,442	7,587
Other income	81	153
Total revenue	60,872	50,989
Expenses
Property	12,655	10,246
General and administrative	11,019	7,530
Property acquisition costs	552	318
Depreciation and amortization	30,280	26,129
Other expenses	260	186
Total expenses	54,766	44,409
Other income (expense)
Interest income	3	3
Interest expense	(10,847)	(8,010)
Loss on extinguishment of debt	(1,134)	0
Gain on the sales of rental property	17,673	0
Total other income (expense)	5,695	(8,007)
Net income (loss) from continuing operations	11,801	(1,427)
Net income (loss)	11,801	(1,427)
Less: income (loss) attributable to noncontrolling interest after preferred stock dividends	455	(198)
Net income (loss) attributable to STAG Industrial, Inc.	11,346	(1,229)
Less: preferred stock dividends	2,912	2,712
Less: amount allocated to participating securities	100	101
Net income (loss) attributable to common stockholders	$ 8,334	$ (4,042)
Weighted average common shares outstanding — basic (in shares)	67,889,217	64,286,213
Weighted average common shares outstanding — diluted (in shares)	67,964,559	64,286,213
Income (loss) per share — basic and diluted
Income (loss) from continuing operations attributable to common stockholders - basic (in dollars per share)	$ 0.12	$ (0.06)
Income (loss) from continuing operations attributable to common stockholders - diluted (in dollars per share)	$ 0.12	$ (0.06)

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 11,801	$ (1,427)
Other comprehensive loss:
Loss on interest rate swaps	(11,823)	(4,005)
Other comprehensive loss	(11,823)	(4,005)
Comprehensive loss	(22)	(5,432)
Net (income) loss attributable to noncontrolling interest after preferred stock dividends	(455)	198
Other comprehensive loss attributable to noncontrolling interest	606	192
Comprehensive income (loss) attributable to STAG Industrial, Inc.	$ 129	$ (5,042)

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Common Stock Dividends in excess of Earnings	Accumulated Other Comprehensive Income (Loss)	Total Stockholders' Equity	Noncontrolling Interest - Unit holders in Operating Partnership
Balance at Dec. 31, 2014	$ 891,524	$ 139,000	$ 644	$ 928,242	$ (203,241)	$ (489)	$ 864,156	$ 27,368
Balance (in shares) at Dec. 31, 2014			64,434,852
Increase (Decrease) in Stockholders' Equity
Proceeds from sale of stock	10,133		$ 4	10,129			10,133
Proceeds from sales of common stock (in shares)			417,115
Offering costs	(202)			(202)			(202)
Issuance of restricted stock, net			$ 1	(1)
Issuance of restricted stock, net (in shares)			92,119
Issuance of common stock (in shares)			3,298
Dividends and distributions, net	(25,656)	(2,712)			(21,824)		(24,536)	(1,120)
Non-cash compensation	1,847			710			710	1,137
Redemption of common units for cash	(64)							(64)
Issuance of units	21,902							21,902
Rebalancing of noncontrolling interest				10,589			10,589	(10,589)
Other comprehensive loss	(4,005)					(3,813)	(3,813)	(192)
Net income (loss)	(1,427)	2,712			(3,941)		(1,229)	(198)
Balance at Mar. 31, 2015	894,052	139,000	$ 649	949,467	(229,006)	(4,302)	855,808	38,244
Balance (in shares) at Mar. 31, 2015			64,947,384
Balance at Dec. 31, 2014	891,524	139,000	$ 644	928,242	(203,241)	(489)	864,156	27,368
Balance (in shares) at Dec. 31, 2014			64,434,852
Balance at Dec. 31, 2015	855,379	139,000	$ 681	1,017,394	(334,623)	(2,350)	820,102	35,277
Balance (in shares) at Dec. 31, 2015			68,077,333
Increase (Decrease) in Stockholders' Equity
Proceeds from sale of stock	75,000	75,000					75,000
Offering costs	(2,590)			(2,590)			(2,590)
Issuance of restricted stock, net			$ 1	(1)
Issuance of restricted stock, net (in shares)			100,737
Issuance of common stock (in shares)			4,732
Dividends and distributions, net	(27,888)	(2,912)			(23,692)		(26,604)	(1,284)
Non-cash compensation	3,631			841			841	2,790
Rebalancing of noncontrolling interest				1,120			1,120	(1,120)
Other comprehensive loss	(11,823)					(11,217)	(11,217)	(606)
Net income (loss)	11,801	2,912			8,434		11,346	455
Balance at Mar. 31, 2016	$ 903,510	$ 214,000	$ 682	$ 1,016,764	$ (349,881)	$ (13,567)	$ 867,998	$ 35,512
Balance (in shares) at Mar. 31, 2016			68,182,802

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ 11,801	$ (1,427)
Adjustment to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	30,280	26,129
Non-cash portion of interest expense	379	299
Intangible amortization in rental income, net	1,666	2,065
Straight-line rent adjustments, net	(424)	(1,293)
Dividends on forfeited equity compensation	2	0
Loss on extinguishment of debt	(4)	0
Gain on sales of rental property	(17,673)	0
Non-cash compensation expense	3,605	1,847
Change in assets and liabilities:
Tenant accounts receivable, net	(461)	(468)
Restricted cash	(46)	(162)
Prepaid expenses and other assets	(4,280)	(3,096)
Accounts payable, accrued expenses and other liabilities	519	(2,242)
Tenant prepaid rent and security deposits	(1,285)	164
Total adjustments	12,286	23,243
Net cash provided by operating activities	24,087	21,816
Cash flows from investing activities:
Acquisitions of land and buildings and improvements	(21,256)	(48,621)
Additions of land and building and improvements	(3,668)	(2,644)
Proceeds from sales of rental property, net	31,890	0
Restricted cash	38	(165)
Acquisition deposits, net	167	(480)
Acquisitions of deferred leasing intangibles	(6,571)	(14,795)
Net cash provided by (used in) investing activities	600	(66,705)
Cash flows from financing activities:
Proceeds from sale of series C preferred stock	75,000	0
Redemption of common units for cash	0	(64)
Proceeds from unsecured credit facility	54,000	62,000
Repayment of unsecured credit facility	(104,000)	(120,000)
Proceeds from unsecured notes	0	120,000
Repayment of mortgage notes	(16,128)	(12,942)
Payment of loan fees and costs	(57)	(930)
Dividends and distributions	(27,597)	(25,314)
Proceeds from sales of common stock	0	10,133
Offering costs	(2,447)	(184)
Net cash provided by (used in) financing activities	(21,229)	32,699
Increase (decrease) in cash and cash equivalents	3,458	(12,190)
Cash and cash equivalents—beginning of period	12,011	23,878
Cash and cash equivalents—end of period	15,469	11,688
Supplemental disclosure:
Cash paid for interest, net of capitalized interest	8,721	6,990
Supplemental schedule of non-cash investing and financing activities
Issuance of units for acquisitions of land and building and improvements and deferred leasing intangibles	0	21,902
Acquisitions of land and buildings and improvements	(39)	(25,936)
Acquisitions of deferred leasing intangibles	(16)	(7,731)
Change in additions of land and building and improvements included in accounts payable, accrued expenses, and other liabilities	(1,761)	1,747
Additions to building and improvements from non-cash compensation expense	(9)	0
Assumption of mortgage note	0	11,765
Change in loan fees and costs and offering costs included in accounts payable, accrued expenses, and other liabilities	(80)	(22)
Dividends and distributions declared but not paid	$ 8,527	$ 7,696

Organization and Description of

Organization and Description of Business	3 Months Ended
	Mar. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business STAG Industrial, Inc. (the “Company”) is an industrial real estate operating company focused on the acquisition and operation of single-tenant, industrial properties throughout the United States. The Company was formed as a Maryland corporation and has elected to be treated and intends to continue to qualify as a real estate investment trust (“REIT”) under Sections 856 through 860 of the Internal Revenue Code of 1986, as amended (the “Code”). The Company is structured as an umbrella partnership REIT, commonly called an UPREIT, and owns substantially all of its assets and conducts substantially all of its business through its operating partnership, STAG Industrial Operating Partnership, L.P., a Delaware limited partnership (the “Operating Partnership”). As of March 31, 2016 and December 31, 2015 , the Company owned a 94.8% and 95.1% , respectively, common equity interest in the Operating Partnership. The Company, through its wholly owned subsidiary, is the sole general partner of the Operating Partnership. As used herein, the “Company” refers to STAG Industrial, Inc. and its consolidated subsidiaries and partnerships, including the Operating Partnership, except where context otherwise requires. As of March 31, 2016 , the Company owned 292 buildings in 38 states with approximately 54.3 million rentable square feet, consisting of 224 warehouse/distribution buildings, 47 light manufacturing buildings and 21 flex/office buildings. The Company’s buildings were approximately 94.8% leased to 260 tenants as of March 31, 2016 .

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Interim Financial Information The accompanying interim financial statements have been presented in conformity with accounting principles generally accepted in the United States of America (“GAAP”) and with the instructions to Form 10-Q and Regulation S-X for interim financial information. Accordingly, these statements do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, the accompanying interim financial statements include all adjustments, consisting of normal recurring items, necessary for their fair presentation in conformity with GAAP. Interim results are not necessarily indicative of results for a full year. The year-end consolidated balance sheet data was derived from audited financial statements, but does not include all disclosures required by GAAP. The information included in this Quarterly Report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2015. Basis of Presentation The Company’s consolidated financial statements include the accounts of the Company, the Operating Partnership and their subsidiaries. Interests in the Operating Partnership not owned by the Company are referred to as “Noncontrolling Common Units.” These Noncontrolling Common Units are held by other limited partners in the form of common units ("Other Common Units") and long term incentive plan units (“LTIP units”) issued pursuant to the STAG Industrial, Inc. 2011 Equity Incentive Plan, as amended (the “2011 Plan”). All significant intercompany balances and transactions have been eliminated in the consolidation of entities. The financial statements of the Company are presented on a consolidated basis for all periods presented. Reclassifications and New Accounting Pronouncements Certain prior year amounts have been reclassified to conform to the current year presentation. In March of 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) 2016-09, Stock Compensation (Topic 718) , which addresses certain aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, forfeitures, and classification on the statement of cash flow. This standard is effective for fiscal years beginning after December 15, 2016, and interim periods within those years, with early adoption permitted. The Company has elected to early adopt this standard effective January 1, 2016. As a result, the Company's policy is to recognize forfeitures in the period which they occur, whereas the former guidance required the Company to estimate expected forfeitures. The adoption of this standard did not have a material effect on the consolidated financial statements. In February of 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e. lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases today. The new standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for sales-type leases, direct financing leases and operating leases. ASU 2016-02 is expected to impact the Company’s consolidated financial statements as the Company has certain operating and land lease arrangements for which it is the lessee. Topic 842 supersedes the previous leases standard, Topic 840, Leases . The standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. The Company is currently in the process of evaluating the impact the adoption of ASU 2016-02 will have on the Company’s financial position or results of operations. In April of 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs (Subtopic 835-30) . ASU 2015-03 requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability. In August of 2015, the FASB issued ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements (Subtopic 835-30) , which clarified that debt issuance costs related to line-of-credit arrangements may be presented as an asset and amortized over the term of the line-of-credit arrangement regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The Company adopted this standard effective January 1, 2016. As a result, debt issuance costs related to the debt liabilities that are not line-of-credit arrangements are included as a direct deduction from the related debt liability and those related to line-of-credit arrangements continue to be included as an asset within prepaid expenses and other assets on the accompanying Consolidated Balance Sheets. The effects of this standard were applied retrospectively to all prior periods presented. The effect of the change in accounting principle was the reduction of unsecured term loans by approximately $0.2 million , unsecured notes by approximately $0.6 million , and mortgage notes by approximately $0.2 million and a corresponding reduction of prepaid expenses and other assets by approximately $1.1 million as of December 31, 2015. In February of 2015, the FASB issued ASU 2015-02, Amendments to Consolidation Analysis (Topic 810) , which amends the current consolidation model. On January 1, 2016, the Company adopted this standard, modifying the analysis it must perform to determine whether it should consolidate certain types of legal entities. The guidance does not amend the existing disclosure requirements for variable interest entities or voting interest model entities. The guidance, however, modified the requirements to qualify under the voting interest model. Under the revised guidance, the Operating Partnership will be a variable interest entity of the Company. As the Operating Partnership is already consolidated in the financial statements of the Company, the identification of this entity as a variable interest entity had no impact on the consolidated financial statements of the Company. There were no other legal entities qualifying under the scope of the revised guidance that were consolidated as a result of the adoption. In addition, there were no voting interest entities under prior existing guidance determined to be variable interest entities under the revised guidance. In January of 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) . The amendments in ASU 2016-01 address certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. The standard primarily affects the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. ASU 2016-01 is effective for the annual periods beginning after December 31, 2017 and for annual periods and interim periods within those years. Early adoption is permitted for all financial statements of fiscal years and interim periods that have not yet been issued. The adoption of ASU 2016-01 is not expected to materially impact the Company’s consolidated financial statements. In August of 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements-Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern . ASU 2014-15 requires management to evaluate whether there are conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern, and to provide certain disclosures when it is probable that the entity will be unable to meet its obligations as they become due within one year after the date that the financial statements are issued. ASU 2014-15 is effective for the annual period ending December 31, 2016 and for annual periods and interim periods thereafter with early adoption permitted. The adoption of ASU 2014-15 is not expected to materially impact the Company’s consolidated financial statements. In May of 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. Revenue from a lease contract with a tenant is not within the scope of this revenue standard. In adopting ASU 2014-09, companies may use either a full retrospective or a modified retrospective approach. Additionally, this guidance requires improved disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. ASU 2014-09 is effective for the first interim period within annual reporting periods beginning after December 15, 2017. Early adoption is permitted for the first interim period within annual reporting periods beginning after December 15, 2016. The Company is currently in the process of evaluating the impact the adoption of ASU 2014-09 will have on the Company’s financial position or results of operations. Rental Property The Company capitalizes costs directly and indirectly related to the development, pre-development, redevelopment or improvement of rental property. Real estate taxes, compensation costs of development personnel, insurance, interest, and other directly related costs during construction periods are capitalized as incurred and depreciated commencing with the date the property is substantially completed. Such costs begin to be capitalized to the development projects from the point the Company is undergoing the necessary activities to get the development ready for its intended use and cease when the development projects are substantially completed and held available for occupancy. Interest is capitalized based on actual capital expenditures from the period when development or redevelopment commences until the asset is ready for its intended use, at the weighted average borrowing rate of the Company's unsecured indebtedness during the period. Tenant Accounts Receivable, net Tenant accounts receivable, net on the accompanying Consolidated Balance Sheets includes both tenant accounts receivable, net and accrued rental income, net. The Company provides an allowance for doubtful accounts against the portion of tenant accounts receivable that is estimated to be uncollectible. As of March 31, 2016 and December 31, 2015 , the Company had an allowance for doubtful accounts of approximately $0.1 million and $0.1 million , respectively. The Company accrues rental income earned, but not yet receivable, in accordance with GAAP. As of March 31, 2016 and December 31, 2015 , the Company had accrued rental income of approximately $16.6 million and $16.1 million , respectively. The Company maintains an allowance for estimated losses that may result from those revenues. As of March 31, 2016 and December 31, 2015 , the Company had an allowance on accrued rental income of $0 and $0 , respectively. As of March 31, 2016 and December 31, 2015 , the Company had approximately $6.1 million and $6.1 million , respectively, of total lease security deposits available in the form of existing letters of credit, which are not reflected on the accompanying Consolidated Balance Sheets. As of March 31, 2016 and December 31, 2015 , the Company had approximately $4.2 million and $4.1 million , respectively, of lease security deposits available in cash, which are included in cash and cash equivalents on the accompanying Consolidated Balance Sheets, and approximately $0.4 million and $0.4 million , respectively, of lease security deposits available in cash, which are included in restricted cash on the accompanying Consolidated Balance Sheets. These funds may be used to settle tenant accounts receivables in the event of a default under the related lease. As of March 31, 2016 and December 31, 2015 , the Company's total liability associated with these lease security deposits was approximately $4.6 million and $4.5 million , respectively, and is included in tenant prepaid rent and security deposits on the accompanying Consolidated Balance Sheets. Related Parties As of March 31, 2016 and December 31, 2015 , the Company had approximately $0.1 million and $0.1 million , respectively, of amounts due from related parties, which are included in prepaid expenses and other assets on the accompanying Consolidated Balance Sheets. Revenue Recognition Tenant Recoveries By the terms of their leases, certain tenants are obligated to pay directly the costs of their properties’ insurance, real estate taxes, ground lease payments, and certain other expenses, and these costs are not reflected on the Company’s consolidated financial statements. The Company does not recognize recovery revenue related to leases where the tenant has assumed the cost for real estate taxes, insurance, ground lease payments and certain other expenses. To the extent any tenant responsible for these costs under its respective lease defaults on its lease or it is deemed probable that the tenant will fail to pay for such costs, the Company will record a liability for such obligation. The Company estimates that real estate taxes, which are the responsibility of these certain tenants, were approximately $2.6 million and $2.5 million for the three months ended March 31, 2016 and March 31, 2015 , respectively. These amounts would have been the maximum expense of the Company had the tenants not met their contractual obligations for these periods. Termination Income On October 20, 2015, the tenant at the Dayton, OH property exercised its early lease termination option per the terms of the lease agreement. The option provided that the tenant's lease terminate effective October 31, 2016 and required the tenant to pay a termination fee of approximately $0.2 million . The termination fee is being recognized on a straight-line basis from October 20, 2015 through the relinquishment of the space on October 31, 2016 and approximately $54,000 is included in rental income on the accompanying Consolidated Statements of Operations for the three months ended March 31, 2016 . Taxes Federal Income Taxes The Company elected to be taxed as a REIT under the Code commencing with its taxable year ended December 31, 2011 and intends to continue to qualify as a REIT. The Company is generally not subject to corporate level income tax on the earnings distributed currently to its stockholders that it derives from its REIT qualifying activities. As a REIT, the Company is required to distribute at least 90% of its REIT taxable income to its stockholders and meet the various other requirements imposed by the Code relating to such matters as operating results, asset holdings, distribution levels and diversity of stock ownership. The Company will not be required to make distributions with respect to income derived from the activities conducted through subsidiaries that the Company elects to treat as taxable REIT subsidiaries (“TRS”) for federal income tax purposes, nor will it have to comply with income, assets, or ownership restrictions inside of the TRS. Certain activities that the Company undertakes must or should be conducted by a TRS, such as performing non-customary services for its tenants and holding assets that it cannot hold directly. A TRS is subject to federal and state income taxes. The Company's TRS recognized a net loss of $11,000 and $0 , during the three months ended March 31, 2016 and March 31, 2015 , respectively, which has been included on the accompanying Consolidated Statements of Operations. State and Local Income, Excise, and Franchise Tax The Company and certain of its subsidiaries are subject to certain state and local income, excise and franchise taxes. Taxes in the amount of $0.2 million and $0.2 million have been recorded in other expenses on the accompanying Consolidated Statements of Operations for the three months ended March 31, 2016 and March 31, 2015 , respectively. Uncertain Tax Positions Tax benefits of uncertain tax positions are recognized only if it is more likely than not that the tax position will be sustained based solely on its technical merits, with the taxing authority having full knowledge of all relevant information. The measurement of a tax benefit for an uncertain tax position that meets the “more likely than not” threshold is based on a cumulative probability model under which the largest amount of tax benefit recognized is the amount with a greater than 50% likelihood of being realized upon ultimate settlement with the taxing authority having full knowledge of all the relevant information. As of March 31, 2016 and December 31, 2015 , there were no liabilities for uncertain tax positions. Concentrations of Credit Risk Concentrations of credit risk relevant to the Company may arise when a number of financing arrangements, including revolving credit facilities or derivatives, are entered into with the same lenders or counterparties, and have similar economic features that would cause their inability to meet contractual obligations. The Company mitigates the concentration of credit risk as it relates to financing arrangements by entering into loan syndications with multiple, reputable financial institutions and diversifying its debt counterparties. The Company also reduces exposure by diversifying its derivatives across multiple counterparties who meet established credit and capital guidelines. Concentration of credit risk may also arise when the Company enters into leases with multiple tenants concentrated in the same industry, or into a significant lease or multiple leases with a single tenant, or tenants are located in the same geographic region, or have similar economic features that would cause their inability to meet contractual obligations, including those to the Company, to be similarly affected. The Company regularly monitors its tenant base to assess potential concentrations of credit risk through financial statement review, tenant management calls, and press releases. Management believes the current credit risk portfolio is reasonably well diversified and does not contain any unusual concentration of credit risk.

Real Estate

Real Estate	3 Months Ended
	Mar. 31, 2016
Real Estate [Abstract]
Real Estate	Real Estate The following table summarizes the components of rental property as of March 31, 2016 and December 31, 2015 . Rental property (in thousands) March 31, 2016 December 31, 2015 Land $ 229,288 $ 228,919 Buildings, net of accumulated depreciation of $110,783 and $104,297, respectivel y 1,227,133 1,232,360 Tenant improvements, net of accumulated depreciation of $27,262 and $26,283, respectively 21,902 23,586 Building and land improvements, net of accumulated depreciation of $22,775 and $19,815, respectivel y 74,635 74,694 Construction in progress 4,932 1,658 Deferred leasing intangibles, net of accumulated amortization of $209,898 and $200,758, respectively 263,867 276,272 Total rental property, net $ 1,821,757 $ 1,837,489 Acquisitions The following tables summarize the acquisitions of the Company during the three months ended March 31, 2016 . Location of property Square Feet Buildings Purchase Price (in thousands) Biddeford, ME 265,126 2 $ 12,452 Fairfield, OH 206,448 1 5,330 Mascot, TN 130,560 1 4,500 Erlanger, KY 108,620 1 5,600 Three months ended March 31, 2016 710,754 5 $ 27,882 The following table summarizes the allocation of the consideration paid at the date of acquisition during the three months ended March 31, 2016 for the acquired assets and liabilities in connection with the acquisitions identified in the table above. Acquired assets and liabilities Purchase price (in thousands) Weighted average amortization period (years) of intangibles at acquisition Land $ 3,236 N/A Buildings 15,879 N/A Tenant improvements 138 N/A Building and land improvements 2,042 N/A Deferred leasing intangibles - In-place leases 3,990 4.5 Deferred leasing intangibles - Tenant relationships 2,541 7.4 Deferred leasing intangibles - Above market leases 245 3.9 Deferred leasing intangibles - Below market leases (189 ) 5.2 Total purchase price $ 27,882 The table below sets forth the results of operations for the properties acquired during the three months ended March 31, 2016 , included in the Company’s Consolidated Statements of Operations from the date of acquisition. Results of operations (in thousands) Three months ended March 31, 2016 Revenue $ 127 Property acquisition costs $ 521 Net income $ 576 The following tables set forth pro forma information for the three months ended March 31, 2016 and March 31, 2015 , respectively. The below pro forma information does not purport to represent what the actual results of operations of the Company would have been had the acquisitions outlined above occurred on the first day of the applicable reporting period, nor do they purport to predict the results of operations of future periods. The pro forma information has not been adjusted for property sales. Pro Forma (in thousands) (1) Three months ended March 31, 2016 Total revenue $ 61,309 Net income $ 12,954 (2) Net income attributable to common stockholders $ 9,428 Pro Forma (in thousands) (3) Three months ended March 31, 2015 Total revenue $ 53,112 Net loss $ 2,300 (2) Net loss attributable to common stockholders $ 4,873 (1) The unaudited pro forma information for the three months ended March 31, 2016 is presented as if the properties acquired during the three months ended March 31, 2016 had occurred at January 1, 2015, the beginning of the reporting period prior to acquisition. (2) The net income for the three months ended March 31, 2016 excludes approximately $0.5 million of property acquisition costs related to the acquisition of buildings that closed during the three months ended March 31, 2016 , and the net loss for the three months ended March 31, 2015 was adjusted to include these acquisition costs. Net loss for the three months ended March 31, 2015 excludes approximately $0.2 million of property acquisition costs related to the acquisition of buildings that closed during the three months ended March 31, 2015 . (3) The unaudited pro forma information for the three months ended March 31, 2015 is presented as if the properties acquired during the three months ended March 31, 2016 and the properties acquired during the three months ended March 31, 2015 had occurred at January 1, 2015 and January 1, 2014, respectively, the beginning of the reporting period prior to acquisition. Dispositions The following table summarizes the dispositions of the Company during the three months ended March 31, 2016 (in thousands, except for square feet and building count). All of the dispositions were accounted for under the full accrual method. Location of property Square Feet Buildings Carrying Value Sales Price Net Proceeds Gain on Sale Wichita, KS (1) 44,760 1 Gresham, OR (2) 420,690 1 Canton, OH (3) 398,000 1 Orangeburg, SC (4) 319,000 1 Three months ended March 31, 2016 1,182,450 4 $ 14,217 $ 32,800 $ 31,890 $ 17,673 (1) The building contributed approximately $0 and $0 to total revenue and approximately $34,000 (exclusive of the gain on sale of rental property and loss on extinguishment of debt) and $26,000 of net loss to the net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (2) The building contributed approximately $0.3 million and $0.4 million to total revenue and approximately ($8,000) (exclusive of the gain on sale of rental property and loss on extinguishment of debt) and $39,000 to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (3) The building contributed approximately $0.3 million and $0.5 million to total revenue and approximately $0.1 million (exclusive of the gain on the sale of rental property) and ($17,000) to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (4) The building contributed approximately $0.2 million and $0.3 million to total revenue and approximately $0.2 million (exclusive of the gain on sale of rental property) and $0.1 million to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. As of March 31, 2016 , the related land, building and improvements, net, and deferred leasing intangibles, net, for two properties located in Kansas City, KS and Parsons, KS were classified as assets held for sale on the accompanying Consolidated Balance Sheets. In April 2016, the Company completed the sale of these properties. Deferred Leasing Intangibles The following table summarizes the deferred leasing intangibles on the accompanying Consolidated Balance Sheets as of March 31, 2016 and December 31, 2015 . March 31, 2016 December 31, 2015 Deferred Leasing Intangibles (in thousands) Gross Accumulated Amortization Net Gross Accumulated Amortization Net Above market leases $ 68,850 $ (32,879 ) $ 35,971 $ 69,815 $ (31,554 ) $ 38,261 Other intangible lease assets 404,915 (177,019 ) 227,896 407,215 (169,204 ) 238,011 Total deferred leasing intangible assets $ 473,765 $ (209,898 ) $ 263,867 $ 477,030 $ (200,758 ) $ 276,272 Below market leases $ 19,344 $ (8,514 ) $ 10,830 $ 19,923 $ (8,536 ) $ 11,387 Total deferred leasing intangible liabilities $ 19,344 $ (8,514 ) $ 10,830 $ 19,923 $ (8,536 ) $ 11,387 The following table sets forth the amortization expense and the net decrease to rental revenue for the amortization of deferred leasing intangibles during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, Deferred Leasing Intangibles Amortization (in thousands) 2016 2015 Net decrease to rental revenue related to above and below market lease amortization $ 1,666 $ 2,064 Amortization expense related to other intangible lease assets $ 15,913 $ 14,275 The following table sets forth the amortization of deferred leasing intangibles over the next five years as of March 31, 2016 . Year Amortization Expense Related to Other Intangible Lease Assets (in thousands) Net Decrease to Rental Revenue Related to Above and Below Market Lease Amortization (in thousands) Remainder of 2016 $ 44,659 $ 4,695 2017 $ 50,687 $ 4,796 2018 $ 40,003 $ 3,557 2019 $ 29,529 $ 3,242 2020 $ 22,463 $ 3,078

Debt

Debt	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Debt	Debt The following table sets forth a summary of the Company’s outstanding indebtedness, including borrowings under the Company’s unsecured credit facility, unsecured term loans, unsecured notes and mortgage notes as of March 31, 2016 and December 31, 2015 . Loan Principal outstanding as of March 31, 2016 (in thousands) Principal outstanding as of December 31, 2015 (in thousands) Interest (1) Current Maturity Prepayment Terms (2) Unsecured credit facility: Unsecured Credit Facility (3) $ 6,000 $ 56,000 L + 1.20% Dec-18-2019 i Total unsecured credit facility 6,000 56,000 Unsecured term loans: Unsecured Term Loan C (4) — — L + 1.35% Sep-29-2020 i Unsecured Term Loan B 150,000 150,000 L + 1.75% Mar-21-2021 ii Unsecured Term Loan A 150,000 150,000 L + 1.80% Mar-31-2022 ii Total unsecured term loans 300,000 300,000 Less: Total unamortized debt issuance costs 221 231 Total carrying value unsecured term loans 299,779 299,769 Unsecured notes: Series F Unsecured Notes 100,000 100,000 3.98 % Jan-05-2023 ii Series A Unsecured Notes 50,000 50,000 4.98 % Oct-1-2024 ii Series D Unsecured Notes 100,000 100,000 4.32 % Feb-20-2025 ii Series B Unsecured Notes 50,000 50,000 4.98 % Jul-1-2026 ii Series C Unsecured Notes 80,000 80,000 4.42 % Dec-30-2026 ii Series E Unsecured Notes 20,000 20,000 4.42 % Feb-20-2027 ii Total unsecured notes 400,000 400,000 Less: Total unamortized debt issuance costs 616 634 Total carrying value unsecured notes 399,384 399,366 Mortgage notes (secured debt): Sun Life Assurance Company of Canada (U.S.) — 3,229 6.05 % Jun-1-2016 iii Webster Bank, National Association 5,471 5,513 4.22 % Aug-4-2016 iii National Life Insurance Company 4,732 4,775 5.75 % Aug-10-2016 iii Union Fidelity Life Insurance Co. 5,663 5,754 5.81 % Apr-30-2017 iv Principal Life Insurance Company 5,632 5,676 5.73 % May-05-2017 iii Webster Bank, National Association 2,923 2,945 3.66 % May-29-2017 iii Webster Bank, National Association 3,148 3,172 3.64 % May-31-2017 iii Wells Fargo, National Association 4,097 4,115 5.90 % Aug-1-2017 v Connecticut General Life Insurance Company-1 Facility 56,942 57,171 6.50 % Feb-1-2018 vi Connecticut General Life Insurance Company-2 Facility 47,345 58,085 5.75 % Feb-1-2018 vi Connecticut General Life Insurance Company-3 Facility 16,338 16,401 5.88 % Feb-1-2018 vi Wells Fargo Bank, National Association CMBS Loan 62,315 63,897 4.31 % Dec-1-2022 vii Total mortgage notes 214,606 230,733 Add: Total unamortized fair market value premiums 325 447 Less: Total unamortized debt issuance costs 204 243 Total carrying value mortgage notes 214,727 230,937 Total / weighted average interest rate (5) $ 919,890 $ 986,072 4.24 % (1) Current interest rate as of March 31, 2016 . At March 31, 2016 , the one-month LIBOR (“L”) was 0.43725% . The current interest rate is not adjusted to include the amortization of deferred financing fees or debt issuance costs incurred in obtaining debt or the unamortized fair market value premiums. The spread over the applicable rate for the Company's unsecured credit facility and unsecured term loans is based on the Company's consolidated leverage ratio, as defined in the respective loan agreements. (2) Prepayment terms consist of (i) pre-payable with no penalty; (ii) pre-payable with penalty; (iii) pre-payable without penalty three months prior to the maturity date; (iv) pre-payable without penalty two months prior to the maturity date; (v) pre-payable without penalty three months prior to the maturity date, however can be defeased; (vi) pre-payable without penalty six months prior to the maturity date; and (vii) pre-payable without penalty three months prior to the maturity date, however can be defeased beginning January 1, 2016. (3) The capacity of the unsecured credit facility is $450.0 million . (4) Capacity of $150.0 million , in which the Company has until September 29, 2016 to draw the full amount. (5) The weighted average interest rate was calculated using the fixed interest rate swapped on the current notional amount of $300.0 million of debt, and is not adjusted to include the amortization of deferred financing fees or debt issuance costs incurred in obtaining debt or the unamortized fair market value premiums. The aggregate undrawn nominal commitments on the combined unsecured credit facility and unsecured term loans as of March 31, 2016 was approximately $594.0 million . The Company's actual borrowing capacity at any given point in time may be less and is restricted to a maximum amount based on the Company's unencumbered assets. Total accrued interest for the Company's indebtedness was $5.5 million and $3.8 million as of March 31, 2016 and December 31, 2015 , respectively, and is included in accounts payable, accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. Deferred financing fees, net of accumulated amortization included in prepaid expenses and other assets on the accompanying Consolidated Balance Sheets were approximately $8.4 million and $8.9 million as of March 31, 2016 and December 31, 2015 , respectively. Debt issuance costs, net of accumulated amortization included as a direct deduction from the related debt liability on the accompanying Consolidated Balance Sheets were approximately $1.0 million and $1.1 million as of March 31, 2016 and December 31, 2015 , respectively. For the three months ended March 31, 2016 and March 31, 2015 , amortization of deferred financing fees and debt issuance costs included in interest expense was approximately $0.5 million and $0.3 million , respectively. On March 17, 2016, the mortgage note held with Connecticut General Life Insurance Company (Facility 2) was partially paid in the amount of approximately $10.5 million in connection with the sale of the Gresham, OR property which had served as partial collateral for the mortgage note. The prepayment fees and associated unamortized deferred financing fees and debt issuance costs of approximately $0.9 million were written off to loss on extinguishment of debt in the accompanying Consolidated Statement of Operations for the three months ended March 31, 2016 . On March 3, 2016, the mortgage note held with Wells Fargo, National Association (CMBS loan) was partially defeased in the amount of approximately $1.2 million in connection with the sale of the Wichita, KS property which had served as partial collateral for the mortgage note. The associated defeasance fees and unamortized deferred financing fees and debt issuance costs of approximately $0.2 million were written off to loss on extinguishment of debt in the accompanying Consolidated Statement of Operations for the three months ended March 31, 2016 . On March 1, 2016 the mortgage note held with Sun Life Assurance Company of Canada (U.S.), in which the property located in Gahanna, OH served as collateral for the mortgage note, was paid in full. The associated unamortized deferred financing fees, debt issuance costs, and fair value market premium were written off as a net gain of approximately $17,000 and is included in loss on extinguishment of debt in the accompanying Consolidated Statement of Operations for the three months ended March 31, 2016 . Financial Covenant Considerations The Company’s ability to borrow under the unsecured credit facility and the unsecured term loans are subject to its ongoing compliance with a number of financial and other covenants. The Company's unsecured notes and mortgage notes also contain covenants. The Company was in compliance with all such applicable restrictions and financial covenants as of March 31, 2016 and December 31, 2015 . In the event of a default under the unsecured credit facility or the unsecured term loans, the Company’s dividend distributions are limited to the minimum amount necessary for the Company to maintain its status as a REIT. Fair Value of Debt The fair value of the Company’s debt was determined by discounting the future cash flows using the current rates at which loans would be made to borrowers with similar credit ratings for loans with similar remaining maturities, similar terms, and similar loan-to-value ratios. The discount rates ranged from approximately 1.74% to 4.19% and 1.58% to 4.82% at March 31, 2016 and December 31, 2015 , respectively, and were applied to each individual debt instrument. The applicable fair value guidance establishes a three tier value hierarchy, which prioritizes the inputs used in measuring fair value. These tiers include: Level 1, defined as observable inputs such as quoted prices in active markets; Level 2, defined as inputs other than quoted prices in active markets that are either directly or indirectly observable; and Level 3, defined as unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions. The fair value of the Company’s debt is based on Level 3 inputs. The following table presents the aggregate principal outstanding of the Company’s debt and the corresponding estimate of fair value as of March 31, 2016 and December 31, 2015 (in thousands). March 31, 2016 December 31, 2015 Principal Outstanding Fair Value Principal Outstanding Fair Value Unsecured credit facility $ 6,000 $ 5,978 $ 56,000 $ 56,000 Unsecured term loans 300,000 304,923 300,000 303,457 Unsecured notes 400,000 409,980 400,000 392,054 Mortgage notes 214,606 220,597 230,733 237,327 Total principal amount 920,606 $ 941,478 986,733 $ 988,838 Add: Total unamortized fair market value premiums 325 447 Less: Total unamortized debt issuance costs 1,041 1,108 Total carrying value $ 919,890 $ 986,072

Use of Derivative Financial Ins

Use of Derivative Financial Instruments	3 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Use of Derivative Financial Instruments	Use of Derivative Financial Instruments Risk Management Objective of Using Derivatives The Company’s use of derivative instruments is limited to the utilization of interest rate swaps to manage interest rate risk exposure on existing and future liabilities and not for speculative purposes. The principal objective of such arrangements is to minimize the risks and related costs associated with the Company’s operating and financial structure. The following table details the Company’s outstanding interest rate swaps as of March 31, 2016 . Interest Rate Trade Date Effective Date Notional Amount (in thousands) Fair Value (in thousands) Pay Fixed Interest Rate Receive Variable Interest Rate Maturity Date PNC Bank, N.A. Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 Bank of America, N.A. Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 UBS AG Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 Royal Bank of Canada Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 RJ Capital Services, Inc. Sep-14-2012 Oct-10-2012 $ 10,000 $ (26 ) 0.7975 % One-month L Sep-10-2017 Bank of America, N.A. Sep-20-2012 Oct-10-2012 $ 25,000 $ (48 ) 0.7525 % One-month L Sep-10-2017 RJ Capital Services, Inc. Sep-24-2012 Oct-10-2012 $ 25,000 $ (39 ) 0.7270 % One-month L Sep-10-2017 Regions Bank Mar-01-2013 Mar-01-2013 $ 25,000 $ (411 ) 1.3300 % One-month L Feb-14-2020 Capital One, N.A. Jun-13-2013 Jul-01-2013 $ 50,000 $ (1,480 ) 1.6810 % One-month L Feb-14-2020 Capital One, N.A. Jun-13-2013 Aug-01-2013 $ 25,000 $ (761 ) 1.7030 % One-month L Feb-14-2020 Regions Bank Sep-30-2013 Feb-03-2014 $ 25,000 $ (1,037 ) 1.9925 % One-month L Feb-14-2020 The Toronto-Dominion Bank Oct-14-2015 Sep-29-2016 $ 25,000 $ (329 ) 1.3830 % One-month L Sep-29-2020 PNC Bank, N.A. Oct-14-2015 Sep-29-2016 $ 50,000 $ (674 ) 1.3906 % One-month L Sep-29-2020 Regions Bank Oct-14-2015 Sep-29-2016 $ 35,000 $ (475 ) 1.3858 % One-month L Sep-29-2020 U.S. Bank, N.A. Oct-14-2015 Sep-29-2016 $ 25,000 $ (339 ) 1.3950 % One-month L Sep-29-2020 Capital One, N.A. Oct-14-2015 Sep-29-2016 $ 15,000 $ (205 ) 1.3950 % One-month L Sep-29-2020 Royal Bank of Canada Jan-08-2015 Mar-20-2015 $ 25,000 $ (809 ) 1.7090 % One-month L Mar-21-2021 The Toronto-Dominion Bank Jan-08-2015 Mar-20-2015 $ 25,000 $ (805 ) 1.7105 % One-month L Mar-21-2021 The Toronto-Dominion Bank Jan-08-2015 Sep-10-2017 $ 100,000 $ (3,346 ) 2.2255 % One-month L Mar-21-2021 Wells Fargo Bank, N.A. Jan-08-2015 Mar-20-2015 $ 25,000 $ (944 ) 1.8280 % One-month L Mar-31-2022 The Toronto-Dominion Bank Jan-08-2015 Feb-14-2020 $ 25,000 $ (359 ) 2.4535 % One-month L Mar-31-2022 Regions Bank Jan-08-2015 Feb-14-2020 $ 50,000 $ (756 ) 2.4750 % One-month L Mar-31-2022 Capital One, N.A. Jan-08-2015 Feb-14-2020 $ 50,000 $ (789 ) 2.5300 % One-month L Mar-31-2022 The fair value of the interest rate swaps outstanding as of March 31, 2016 and December 31, 2015 was as follows: Balance Sheet Line Item (in thousands) Notional Amount March 31, 2016 Fair Value March 31, 2016 Notional Amount December 31, 2015 Fair Value December 31, 2015 Interest rate swaps-Asset $ — $ — $ 275,000 $ 1,867 Interest rate swaps-Liability $ 675,000 $ (13,732 ) $ 400,000 $ (3,766 ) Cash Flow Hedges of Interest Rate Risk The Company’s objectives in using interest rate swaps are to add stability to interest expense and to manage its exposure to interest rate movements. The Company uses interest rate swaps to fix the rate of its long term variable rate debt. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for the Company making fixed-rate payments over the life of the agreements without exchange of the underlying notional amount. The effective portion of changes in the fair value of derivatives designated and qualified as cash flow hedges is recorded in accumulated other comprehensive loss and will be reclassified to interest expense in the period that the hedged forecasted transaction affects earnings on the Company’s variable rate debt. The ineffective portion of the change in fair value of the derivatives is recognized directly in earnings into interest expense. During the three months ended March 31, 2016 and March 31, 2015 , the Company did not record any hedge ineffectiveness related to the hedged derivatives. The Company estimates that approximately $3.1 million will be reclassified from accumulated other comprehensive loss as an increase to interest expense over the next 12 months. The table below details the location in the financial statements of the gain or loss recognized on interest rate swaps designated as cash flow hedges for the three months ended March 31, 2016 and March 31, 2015 , (in thousands). Three Months Ended March 31, 2016 2015 Amount of loss recognized in accumulated other comprehensive income (loss) on interest rate swaps (effective portion) $ 12,568 $ 4,671 Amount of loss reclassified from accumulated other comprehensive income (loss) into income as interest expense (effective portion) $ 745 $ 666 Amount of gain (loss) recognized in interest expense (ineffective portion and amount excluded from effectiveness testing) $ — $ — Credit-risk-related Contingent Features The Company has agreements with each of its derivative counterparties that contain a provision where the Company could be declared in default on its derivative obligations if repayment of the underlying indebtedness is accelerated by the lender due to the Company's default on the indebtedness. As of March 31, 2016 , the fair values of all of the Company's 23 interest rate swaps were in a liability position of approximately $14.6 million , excluding any adjustment for nonperformance risk related to these agreements. The adjustment for nonperformance risk included in the fair value of the Company’s net liability position was approximately $0.9 million as of March 31, 2016 . Accrued interest expense for the Company's interest rate swaps was approximately $0.1 million as of March 31, 2016 and is included in accounts payable, accrued expenses and other liabilities on the accompanying Consolidated Balance Sheets. As of March 31, 2016 , the Company has not posted any collateral related to these agreements. If the Company had breached any of its provisions at March 31, 2016 , it could have been required to settle its obligations under the agreement of the interest rate swaps in a liability position at its termination value of approximately $14.8 million . Fair Value of Interest Rate Swaps The Company’s valuation of the interest rate swaps is determined using widely accepted valuation techniques including discounted cash flow analysis on the expected cash flows of each derivative. This analysis reflects the contractual terms of the derivatives, including the period to maturity, and uses observable market-based inputs including interest rate curves. The fair values of interest rate swaps are determined by using the market standard methodology of netting the discounted future fixed cash payments and the discounted expected variable cash receipts. The variable cash receipts are based on an expectation of future interest rates (forward curves) derived from observable market interest rate curves. The Company incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered the impact of netting and any applicable credit enhancements, such as collateral postings, thresholds, mutual puts, and guarantees. Although the Company has determined that the majority of the inputs used to value its derivatives fall within Level 2 of the fair value hierarchy, the credit valuation adjustments associated with its derivatives utilize Level 3 inputs, such as estimates of current credit spreads to evaluate the likelihood of default by itself and its counterparties. However, as of March 31, 2016 and December 31, 2015 , the Company has assessed the significance of the impact of the credit valuation adjustments on the overall valuation of its derivative positions and has determined that the credit valuation adjustments are not significant to the overall valuation of its derivatives. As a result, the Company has determined that its derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. The following sets forth the Company’s financial instruments that are accounted for at fair value on a recurring basis as of March 31, 2016 and December 31, 2015 . Fair Value Measurements as of Balance Sheet Line Item (in thousands) Fair Value March 31, 2016 Level 1 Level 2 Level 3 Interest rate swaps-Asset $ — $ — $ — $ — Interest rate swaps-Liability $ (13,732 ) $ — $ (13,732 ) $ — Fair Value Measurements as of Balance Sheet Line Item (in thousands) Fair Value December 31, 2015 Level 1 Level 2 Level 3 Interest rate swaps-Asset $ 1,867 $ — $ 1,867 $ — Interest rate swaps-Liability $ (3,766 ) $ — $ (3,766 ) $ —

Equity

Equity	3 Months Ended
	Mar. 31, 2016
Stockholders' Equity Note [Abstract]
Equity	Equity Preferred Stock Pursuant to its charter, the Company is authorized to issue 15,000,000 shares of preferred stock, par value $0.01 per share. The table below sets forth the Company’s outstanding preferred stock issuances as of March 31, 2016 . Preferred Stock Issuances Issuance Date Number of Shares Price and Liquidation Value per share Interest Rate Series A Preferred Stock November 2, 2011 2,760,000 $ 25.00 9.000 % Series B Preferred Stock April 16, 2013 2,800,000 $ 25.00 6.625 % Series C Preferred Stock March 17, 2016 3,000,000 $ 25.00 6.875 % Dividends on the Series A Preferred Stock, Series B Preferred Stock, and Series C Preferred Stock (collectively, the "Preferred Stock Issuances") are payable quarterly in arrears on or about the last day of March, June, September, and December of each year. Dividends for the Series C Preferred Stock will accrue and be cumulative from and including March 17, 2016 to the first payment date on June 30, 2016. The Preferred Stock Issuances rank on parity and rank senior to the Company’s common stock with respect to dividend rights and rights upon the liquidation, dissolution or winding up of the Company. The Preferred Stock Issuances have no stated maturity date and are not subject to mandatory redemption or any sinking fund. Generally, the Company is not permitted to redeem the Series A Preferred Stock, Series B Preferred Stock, and Series C Preferred Stock prior to November 2, 2016, April 16, 2018, and March 17, 2021, respectively, except in limited circumstances relating to the Company’s ability to qualify as a REIT and in certain other circumstances related to a change of control. The tables below set forth the dividends attributable to the Preferred Stock Issuance s during the three months ended March 31, 2016 and the year ended December 31, 2015 : Quarter Ended 2016 Declaration Date Series A Series B Payment Date March 31 February 22, 2016 $ 0.5625 $ 0.4140625 March 31, 2016 Total $ 0.5625 $ 0.4140625 Quarter Ended 2015 Declaration Date Series A Series B Payment Date December 31 October 22, 2015 $ 0.5625 $ 0.4140625 December 31, 2015 September 30 July 21, 2015 0.5625 0.4140625 September 30, 2015 June 30 May 4, 2015 0.5625 0.4140625 June 30, 2015 March 31 February 20, 2015 0.5625 0.4140625 March 31, 2015 Total $ 2.2500 $ 1.6562500 On May 2, 2016 , the Company’s board of directors declared the Series A Preferred Stock and Series B Preferred Stock dividend for the quarter ending June 30, 2016 at a quarterly rate of $0.5625 per share and $0.4140625 per share, respectively. On May 2, 2016 , the Company’s board of directors declared the Series C Preferred Stock dividend for the period from the issuance date of March 17, 2016 through June 30, 2016 at a rate of $0.49653 per share. Common Stock The following sets forth the Company’s at-the market ("ATM") common stock offering program as of March 31, 2016 . Once the ATM offering program is associated with the Company’s most recent shelf registration statement, the Company may from time to time sell its common stock through sales agents under the program. ATM Stock Offering Program (in thousands) Date Maximum Aggregate Offering Price Aggregate Common Stock Available as of March 31, 2016 2014 $200 million ATM September 10, 2014 $ 200,000 $ 107,380 The table below sets forth the activity for the ATM common stock offering programs during the year ended December 31, 2015 (in thousands, except share data). There was no activity for the ATM common stock offering programs during three months ended March 31, 2016 . Year ended December 31, 2015 ATM Stock Offering Program Shares Weighted Average Price Per Share Gross Sales Net 2014 $200 million ATM 2,661,403 $ 21.63 $ 57,571 $ 864 $ 56,707 2014 $150 million ATM 795,000 $ 21.79 17,321 260 17,061 Total/weighted average 3,456,403 $ 21.67 $ 74,892 $ 1,124 $ 73,768 Dividends The table below sets forth the dividends attributable to the common stock during the three months ended March 31, 2016 and the year ended December 31, 2015 . Month Ended 2016 Declaration Date Record Date Per Share Payment Date June 30 February 22, 2016 June 30, 2016 $ 0.115833 July 15, 2016 May 31 February 22, 2016 May 31, 2016 0.115833 June 15, 2016 April 30 February 22, 2016 April 29, 2016 0.115833 May 16, 2016 March 31 October 22, 2015 March 31, 2016 0.115833 April 15, 2016 February 29 October 22, 2015 February 29, 2016 0.115833 March 15, 2016 January 31 October 22, 2015 January 29, 2016 0.115833 February 16, 2016 Total $ 0.694998 Month Ended 2015 Declaration Date Record Date Per Share Payment Date December 31 July 21, 2015 December 31, 2015 $ 0.1150 January 15, 2016 November 30 July 21, 2015 November 30, 2015 0.1150 December 15, 2015 October 31 July 21, 2015 October 30, 2015 0.1150 November 16, 2015 September 30 May 4, 2015 September 30, 2015 0.1150 October 15, 2015 August 31 May 4, 2015 August 31, 2015 0.1150 September 15, 2015 July 31 May 4, 2015 July 31, 2015 0.1150 August 17, 2015 June 30 February 20, 2015 June 30, 2015 0.1125 July 15, 2015 May 31 February 20, 2015 May 29, 2015 0.1125 June 15, 2015 April 30 February 20, 2015 April 30, 2015 0.1125 May 15, 2015 March 31 October 30, 2014 March 31, 2015 0.1125 April 15, 2015 February 28 October 30, 2014 February 27, 2015 0.1125 March 16, 2015 January 31 October 30, 2014 January 31, 2015 0.1125 February 17, 2015 Total $ 1.3650 On May 2, 2016 , the Company’s board of directors declared the common stock dividend for the months ending July 31, 2016 , August 31, 2016 and September 30, 2016 at a monthly rate of $0.115833 per share of common stock. Restricted Stock-Based Compensation Pursuant to the 2011 Plan, the Company grants restricted shares of common stock to certain employees of the Company. The restricted shares of common stock are subject to time-based vesting. Restricted shares of common stock granted on January 8, 2016, subject to the recipient’s continued employment, will vest in four equal installments on January 1 of each year. Holders of restricted shares of common stock have voting rights and rights to receive dividends. Restricted shares of common stock may not be sold, assigned, transferred, pledged or otherwise disposed of and are subject to a risk of forfeiture prior to the expiration of the applicable vesting period. The following table summarizes activity related to the Company’s unvested restricted shares of common stock for the three months ended March 31, 2016 and the year ended December 31, 2015 . Unvested restricted shares of common stock Shares Balance at December 31, 2014 263,916 Granted 94,290 (1) Vested (72,185 ) Forfeited (14,906 ) Balance at December 31, 2015 271,115 Granted 101,289 (2) Vested (84,336 ) Forfeited (552 ) Balance at March 31, 2016 287,516 (1) The grant date fair value per share was $26.17 . (2) The grant date fair value per share was $17.98 . The unrecognized compensation expense associated with the Company’s restricted shares of common stock at March 31, 2016 was approximately $4.9 million and is expected to be recognized over a weighted average period of approximately 2.7 years . The following table summarizes the fair value at vesting date for the restricted shares of common stock vested during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, 2016 2015 Vested restricted shares of common stock 84,336 57,528 Fair value of vested restricted shares of common stock (in thousands) $ 1,522 $ 1,425

Noncontrolling Interest

Noncontrolling Interest	3 Months Ended
	Mar. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling Interest	Noncontrolling Interest The Company is structured as an UPREIT, and owns substantially all of its assets and conducts substantially all of its business through its Operating Partnership. The Company’s consolidated financial statements include the accounts of the Company, the Operating Partnership and their subsidiaries. Noncontrolling interest in the Company consists of LTIP units and Other Common Units in the Operating Partnership that are not owned by the Company. The table below summarizes the activity for noncontrolling interest in the Company for the three months ended March 31, 2016 and the year ended December 31, 2015 . LTIP Units Other Common Units Total Noncontrolling Common Units Noncontrolling Interest Balance at December 31, 2014 1,307,036 1,124,813 2,431,849 3.6 % Granted/Issued 323,069 864,283 1,187,352 N/A Forfeitures — — — N/A Conversions from LTIP units to Other Common Units (20,000 ) 20,000 — N/A Redemptions from Other Common Units to common stock — (90,824 ) (90,824 ) N/A Redemption of Other Common Units for cash — (2,400 ) (2,400 ) N/A Balance at December 31, 2015 1,610,105 1,915,872 3,525,977 4.9 % Granted/Issued 176,396 — 176,396 N/A Forfeitures — — — N/A Balance at March 31, 2016 1,786,501 1,915,872 3,702,373 5.2 % The Company adjusts the carrying value of noncontrolling interest to reflect its share of the book value of the Operating Partnership when there has been a change in the Company’s ownership of the Operating Partnership. Such adjustments are recorded to additional paid-in capital as a rebalancing of noncontrolling interest on the accompanying Consolidated Statements of Equity. LTIP Units LTIP units are granted to certain executive officers and senior employees of the Company as part of their compensation, and to independent directors for their service. LTIP units are valued by reference to the value of the Company’s common stock and are subject to such conditions and restrictions as the compensation committee of the board of directors may determine, including continued employment or service, computation of financial metrics and achievement of pre-established performance goals and objectives. LTIP units granted on January 6, 2016 to independent directors, subject to the recipient’s continued service, will vest on January 1, 2017. LTIP units granted on January 8, 2016 to certain senior executive officers and senior employees, subject to the recipient’s continued employment, will vest quarterly over four years, with the first vesting date being March 31, 2016. LTIP units granted on February 22, 2016 to certain senior executive officers, subject to the recipient’s continued employment, will vest quarterly over four years, with the first vesting date being March 31, 2016. Vested LTIP units can be converted to Other Common Units on a one-for-one basis once a material equity transaction has occurred that results in the accretion of the member’s capital account to the economic equivalent of an Other Common Unit. All LTIP units, whether vested or not, will receive the same monthly per unit distributions as Other Common Units, which equal per share dividends on common stock. The LTIP units issued under the 2011 Plan were valued using the Monte Carlo lattice binomial option-pricing model at the grant date. The fair value of the LTIP units are based on Level 3 inputs and are non-recurring fair value measurements. The table below sets forth the assumptions used in valuing such LTIP units for the three months ended March 31, 2016 . Assumptions Grant date February 22, 2016 January 8, 2016 January 6, 2016 Expected term (years) 10 10 10 Expected volatility 22.0 % 22.0 % 22.0 % Expected dividend yield 6.0 % 6.0 % 6.0 % Risk-free interest rate 1.01 % 1.28 % 1.36 % Fair value of LTIP units at issuance (in thousands) $ 277 $ 2,254 $ 390 LTIP units at issuance 18,386 135,546 22,464 Fair value unit price per LTIP unit at issuance $ 15.07 $ 16.63 $ 17.36 On January 25, 2016, the Company and Geoffrey G. Jervis, the Company’s Chief Financial Officer, Executive Vice President and Treasurer, agreed that Mr. Jervis’s employment with the Company would terminate effective February 25, 2016. Pursuant to the terms and conditions of the executive employment agreement and LTIP Unit agreements between the Company and Mr. Jervis, and the Company’s 2015 Outperformance Program ("OPP"), Mr. Jervis received a lump sum cash payment, the continuation of certain insurance benefits, immediate vesting of outstanding LTIP units, and eligibility to receive a pro-rated award payment under the OPP. Accordingly, the Company accelerated the expense recognition of Mr. Jervis' unvested LTIP units in the amount of approximately $1.6 million , which is included in general and administrative expenses for the three months ended March 31, 2016 on the accompanying Consolidated Statements of Operations. Additionally, the unrecognized compensation expense associated with Mr. Jervis' participation in the OPP after February 25, 2016 will not be recognized. The Company also incurred approximately $1.5 million related to the lump sum cash payment and continuation of certain insurance benefits, which is included in general and administrative expenses for the three months ended March 31, 2016 on the accompanying Consolidated Statements of Operations. The following table summarizes activity related to the Company’s unvested LTIP units for the three months ended March 31, 2016 and the year ended December 31, 2015 . Unvested LTIP units LTIP Units Balance at December 31, 2014 448,887 Granted 323,069 Vested (237,046 ) Forfeited — Balance at December 31, 2015 534,910 Granted 176,396 Vested (170,277 ) Forfeited — Balance at March 31, 2016 541,029 The unrecognized compensation expense associated with the Company’s LTIP units at March 31, 2016 was approximately $9.9 million and is expected to be recognized over a weighted average period of approximately 3.0 years . The following table summarizes the fair value at vesting date for the LTIP units vested during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, 2016 2015 Vested LTIP units 170,277 51,420 Fair value of vested LTIP units (in thousands) $ 3,089 $ 1,209 Other Common Units Other Common Units and shares of the Company’s common stock have essentially the same economic characteristics in that Other Common Units directly, and shares of the Company’s common stock indirectly, through the Company’s interest in the Operating Partnership, share equally in the total net income or loss distributions of the Operating Partnership. Subject to certain restrictions, investors who own Other Common Units have the right to cause the Operating Partnership to redeem any or all of their Other Common Units for cash equal to the then-current value of one share of the Company’s common stock, or, at the Company’s election, shares of common stock on a one-for-one basis. The value of a share of common stock is calculated as the average common stock closing price on the NYSE for the 10 trading days immediately preceding the redemption notice date. Each Other Common Unit will receive the same monthly distribution as a share of common stock.

Equity Incentive Plan

Equity Incentive Plan	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Incentive Plan	Equity Incentive Plan On March 8, 2016, the Company granted performance units, approved by the compensation committee of the board of directors, under the 2011 Plan to provide certain key employees of the Company with incentives designed to align those key employees' interests more closely with those of the shareholders. The ultimate value of the performance units depends on the Company’s total stockholder return ("TSR") over a three -year period commencing January 1, 2016 and ending on December 31, 2018 (the "measuring period"). At the end of the three -year measuring period, the performance units convert into shares of common stock at a rate depending on the Company’s TSR over the measuring period as compared to three different benchmarks and on the absolute amount of the Company’s TSR. A recipient of performance units may receive as few as zero shares or as many as 250% of the number of target units, plus deemed dividends. The target amount of the performance units is nominally allocated as: i) 25% to the Company’s TSR compared to the TSR of an industry peer group; ii) 25% to the Company’s TSR compared to the TSR of a size-based peer group; and iii) 50% to the Company’s TSR compared to the TSR of the companies in the MSCI US REIT index. No dividends are paid to the recipient during the measuring period. At the end of the measuring period, if the Company’s TSR is such that the recipient earns shares of common stock (“Award Shares”), the recipient will receive additional common stock relating to dividends deemed to have been paid and reinvested on the Award Shares. The Company, in the discretion of the compensation committee of the board of directors, may pay the cash value of the deemed dividends instead of issuing additional shares. The number of Award Shares is determined at the end of the measuring period, and one-half of the Award Shares and all dividend shares vest immediately. The other one-half of the Award Shares will be restricted (subject to forfeiture) and vest one year after the end of the measuring period. The fair value of the performance units at the date of grant was $2.6 million , as determined by a lattice-binomial option-pricing model based on a Monte Carlo simulation using a weighted average volatility factor of 23.0% , a weighted average risk-free interest rate of 1.0849% , and a weighted average expected dividend yield of 6.0% . The performance unit equity compensation expense is recognized into earnings on a straight-line basis from the grant date over the respective vesting periods. The unrecognized compensation expense associated with the OPP at March 31, 2016 was approximately $0.8 million and is expected to be recognized over a weighted average period of approximately 1.8 years . The unrecognized compensation expense associated with the performance units at March 31, 2016 was approximately $2.6 million and is expected to be recognized over a weighted average period of approximately 3.2 years . Non-cash Compensation Expense The following table summarizes the amount recorded in general and administrative expenses in the accompanying Consolidated Statements of Operations for the amortization of restricted shares of common stock, LTIP units, the OPP, performance units, and the Company’s board of directors’ compensation. Three months ended March 31, Non-cash compensation expense (in thousands) 2016 2015 Restricted stock $ 558 $ 492 LTIP units 2,795 (1) 1,137 Outperformance program 119 131 Performance units 53 — Board of directors compensation (2) 80 87 Total non-cash compensation expense $ 3,605 $ 1,847 (1) Inclusive of approximately of $1.6 million non-cash compensation expense during the three months ended March 31, 2016 associated with the severance cost of an executive officer as discussed Note 7. (2) All of the Company’s independent directors elected to receive shares of common stock in lieu of cash for their service during the three months ended March 31, 2016 and March 31, 2015 . The number of shares of common stock granted is calculated based on the trailing 10 days average common stock price ending on the third business day preceding the grant date.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The Company uses the two-class method of computing earnings per common share, which is an earnings allocation formula that determines earnings per share for common stock and any participating securities according to dividends declared (whether paid or unpaid) and participation rights in undistributed earnings. A participating security is defined by GAAP as an unvested stock-based payment award containing non-forfeitable rights to dividends and must be included in the computation of earnings per share pursuant to the two-class method. Unvested restricted stock awards are considered participating securities as these stock-based awards contain non-forfeitable rights to dividends, unless and until a forfeiture occurs. During the three months ended March 31, 2016 and March 31, 2015 , there were 285,458 and 290,280 , respectively, unvested shares of restricted stock on a weighted average basis that were considered participating securities. During the three months ended March 31, 2016 , there were 43,529 and 31,813 of unvested shares of restricted stock and performance units, respectively, on a weighted average basis that were dilutive. There were no dilutive shares during the three months ended March 31, 2015 . The following tables set forth the computation of basic and diluted earnings per common share for the three months ended March 31, 2016 and March 31, 2015 . Earnings per share (in thousands, except share data) Three months ended March 31, 2016 Numerator Net income $ 11,801 Less: preferred stock dividends 2,912 Less: amount allocated to participating securities 100 Less: income attributable to noncontrolling interest after preferred stock dividends 455 Net income attributable to common stockholders $ 8,334 Denominator Weighted average common shares outstanding — basic 67,889,217 Weighted average common shares outstanding — diluted 67,964,559 Income per share — basic and diluted Income from continuing operations attributable to common stockholders - basic $ 0.12 Income from continuing operations attributable to common stockholders - diluted $ 0.12 Earnings per share (in thousands, except share data) Three months ended March 31, 2015 Numerator Net loss $ (1,427 ) Less: preferred stock dividends 2,712 Less: amount allocated to participating securities 101 Less: loss attributable to noncontrolling interest after preferred stock dividends (198 ) Net loss attributable to common stockholders $ (4,042 ) Denominator Weighted average common shares outstanding—basic and diluted 64,286,213 Loss per share - basic and diluted $ (0.06 )

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company is subject to various legal proceedings and claims that arise in the ordinary course of business. These matters are generally covered by insurance subject to deductible requirements. Management believes that the ultimate settlement of these actions will not have a material adverse effect on the Company’s financial position, results of operations or cash flows. The Company is subject to a one-time incentive fee based on aggregate performance thresholds of the acquired buildings sourced by Columbus Nova Real Estate Acquisition Group, LLC. As of March 31, 2016 and December 31, 2015 , the fair value of the incentive fee was zero . The fair value was calculated using the following key Level 3 inputs: discount rate of approximately 9.5% and exit capitalization rate of 9.8% . The Company has letters of credit of approximately $3.4 million related to development projects and its corporate office lease.

Subsequent Events

Subsequent Events	3 Months Ended
	Mar. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events No significant recognized or non-recognized subsequent events were noted.

Summary of Significant Accoun19

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company’s consolidated financial statements include the accounts of the Company, the Operating Partnership and their subsidiaries. Interests in the Operating Partnership not owned by the Company are referred to as “Noncontrolling Common Units.” These Noncontrolling Common Units are held by other limited partners in the form of common units ("Other Common Units") and long term incentive plan units (“LTIP units”) issued pursuant to the STAG Industrial, Inc. 2011 Equity Incentive Plan, as amended (the “2011 Plan”). All significant intercompany balances and transactions have been eliminated in the consolidation of entities. The financial statements of the Company are presented on a consolidated basis for all periods presented.
Reclassification	Certain prior year amounts have been reclassified to conform to the current year presentation.
Adoption of New Accounting Pronouncements	In March of 2016, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update (“ASU”) 2016-09, Stock Compensation (Topic 718) , which addresses certain aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, forfeitures, and classification on the statement of cash flow. This standard is effective for fiscal years beginning after December 15, 2016, and interim periods within those years, with early adoption permitted. The Company has elected to early adopt this standard effective January 1, 2016. As a result, the Company's policy is to recognize forfeitures in the period which they occur, whereas the former guidance required the Company to estimate expected forfeitures. The adoption of this standard did not have a material effect on the consolidated financial statements. In February of 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e. lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight line basis over the term of the lease, respectively. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less will be accounted for similar to existing guidance for operating leases today. The new standard requires lessors to account for leases using an approach that is substantially equivalent to existing guidance for sales-type leases, direct financing leases and operating leases. ASU 2016-02 is expected to impact the Company’s consolidated financial statements as the Company has certain operating and land lease arrangements for which it is the lessee. Topic 842 supersedes the previous leases standard, Topic 840, Leases . The standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, with early adoption permitted. The Company is currently in the process of evaluating the impact the adoption of ASU 2016-02 will have on the Company’s financial position or results of operations. In April of 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs (Subtopic 835-30) . ASU 2015-03 requires debt issuance costs related to a recognized debt liability to be presented in the balance sheet as a direct deduction from the carrying amount of the debt liability. In August of 2015, the FASB issued ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements (Subtopic 835-30) , which clarified that debt issuance costs related to line-of-credit arrangements may be presented as an asset and amortized over the term of the line-of-credit arrangement regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The Company adopted this standard effective January 1, 2016. As a result, debt issuance costs related to the debt liabilities that are not line-of-credit arrangements are included as a direct deduction from the related debt liability and those related to line-of-credit arrangements continue to be included as an asset within prepaid expenses and other assets on the accompanying Consolidated Balance Sheets. The effects of this standard were applied retrospectively to all prior periods presented. The effect of the change in accounting principle was the reduction of unsecured term loans by approximately $0.2 million , unsecured notes by approximately $0.6 million , and mortgage notes by approximately $0.2 million and a corresponding reduction of prepaid expenses and other assets by approximately $1.1 million as of December 31, 2015. In February of 2015, the FASB issued ASU 2015-02, Amendments to Consolidation Analysis (Topic 810) , which amends the current consolidation model. On January 1, 2016, the Company adopted this standard, modifying the analysis it must perform to determine whether it should consolidate certain types of legal entities. The guidance does not amend the existing disclosure requirements for variable interest entities or voting interest model entities. The guidance, however, modified the requirements to qualify under the voting interest model. Under the revised guidance, the Operating Partnership will be a variable interest entity of the Company. As the Operating Partnership is already consolidated in the financial statements of the Company, the identification of this entity as a variable interest entity had no impact on the consolidated financial statements of the Company. There were no other legal entities qualifying under the scope of the revised guidance that were consolidated as a result of the adoption. In addition, there were no voting interest entities under prior existing guidance determined to be variable interest entities under the revised guidance. In January of 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities (Subtopic 825-10) . The amendments in ASU 2016-01 address certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. The standard primarily affects the accounting for equity investments, financial liabilities under the fair value option, and the presentation and disclosure requirements for financial instruments. ASU 2016-01 is effective for the annual periods beginning after December 31, 2017 and for annual periods and interim periods within those years. Early adoption is permitted for all financial statements of fiscal years and interim periods that have not yet been issued. The adoption of ASU 2016-01 is not expected to materially impact the Company’s consolidated financial statements. In August of 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements-Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern . ASU 2014-15 requires management to evaluate whether there are conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern, and to provide certain disclosures when it is probable that the entity will be unable to meet its obligations as they become due within one year after the date that the financial statements are issued. ASU 2014-15 is effective for the annual period ending December 31, 2016 and for annual periods and interim periods thereafter with early adoption permitted. The adoption of ASU 2014-15 is not expected to materially impact the Company’s consolidated financial statements. In May of 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . ASU 2014-09 is a comprehensive new revenue recognition model requiring a company to recognize revenue to depict the transfer of goods or services to a customer at an amount reflecting the consideration it expects to receive in exchange for those goods or services. Revenue from a lease contract with a tenant is not within the scope of this revenue standard. In adopting ASU 2014-09, companies may use either a full retrospective or a modified retrospective approach. Additionally, this guidance requires improved disclosures regarding the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. ASU 2014-09 is effective for the first interim period within annual reporting periods beginning after December 15, 2017. Early adoption is permitted for the first interim period within annual reporting periods beginning after December 15, 2016. The Company is currently in the process of evaluating the impact the adoption of ASU 2014-09 will have on the Company’s financial position or results of operations.
Rental Property	Rental Property The Company capitalizes costs directly and indirectly related to the development, pre-development, redevelopment or improvement of rental property. Real estate taxes, compensation costs of development personnel, insurance, interest, and other directly related costs during construction periods are capitalized as incurred and depreciated commencing with the date the property is substantially completed. Such costs begin to be capitalized to the development projects from the point the Company is undergoing the necessary activities to get the development ready for its intended use and cease when the development projects are substantially completed and held available for occupancy. Interest is capitalized based on actual capital expenditures from the period when development or redevelopment commences until the asset is ready for its intended use, at the weighted average borrowing rate of the Company's unsecured indebtedness during the period.
Tenant Accounts Receivable, net	Tenant Accounts Receivable, net Tenant accounts receivable, net on the accompanying Consolidated Balance Sheets includes both tenant accounts receivable, net and accrued rental income, net. The Company provides an allowance for doubtful accounts against the portion of tenant accounts receivable that is estimated to be uncollectible.
Revenue Recognition	Revenue Recognition Tenant Recoveries By the terms of their leases, certain tenants are obligated to pay directly the costs of their properties’ insurance, real estate taxes, ground lease payments, and certain other expenses, and these costs are not reflected on the Company’s consolidated financial statements. The Company does not recognize recovery revenue related to leases where the tenant has assumed the cost for real estate taxes, insurance, ground lease payments and certain other expenses. To the extent any tenant responsible for these costs under its respective lease defaults on its lease or it is deemed probable that the tenant will fail to pay for such costs, the Company will record a liability for such obligation.
Taxes	Taxes Federal Income Taxes The Company elected to be taxed as a REIT under the Code commencing with its taxable year ended December 31, 2011 and intends to continue to qualify as a REIT. The Company is generally not subject to corporate level income tax on the earnings distributed currently to its stockholders that it derives from its REIT qualifying activities. As a REIT, the Company is required to distribute at least 90% of its REIT taxable income to its stockholders and meet the various other requirements imposed by the Code relating to such matters as operating results, asset holdings, distribution levels and diversity of stock ownership. The Company will not be required to make distributions with respect to income derived from the activities conducted through subsidiaries that the Company elects to treat as taxable REIT subsidiaries (“TRS”) for federal income tax purposes, nor will it have to comply with income, assets, or ownership restrictions inside of the TRS. Certain activities that the Company undertakes must or should be conducted by a TRS, such as performing non-customary services for its tenants and holding assets that it cannot hold directly. A TRS is subject to federal and state income taxes. The Company's TRS recognized a net loss of $11,000 and $0 , during the three months ended March 31, 2016 and March 31, 2015 , respectively, which has been included on the accompanying Consolidated Statements of Operations. State and Local Income, Excise, and Franchise Tax The Company and certain of its subsidiaries are subject to certain state and local income, excise and franchise taxes. Taxes in the amount of $0.2 million and $0.2 million have been recorded in other expenses on the accompanying Consolidated Statements of Operations for the three months ended March 31, 2016 and March 31, 2015 , respectively. Uncertain Tax Positions Tax benefits of uncertain tax positions are recognized only if it is more likely than not that the tax position will be sustained based solely on its technical merits, with the taxing authority having full knowledge of all relevant information. The measurement of a tax benefit for an uncertain tax position that meets the “more likely than not” threshold is based on a cumulative probability model under which the largest amount of tax benefit recognized is the amount with a greater than 50% likelihood of being realized upon ultimate settlement with the taxing authority having full knowledge of all the relevant information. As of March 31, 2016 and December 31, 2015 , there were no liabilities for uncertain tax positions.

Real Estate (Tables)

Real Estate (Tables)	3 Months Ended
	Mar. 31, 2016
Real Estate [Abstract]
Schedule of components of rental property	The following table summarizes the components of rental property as of March 31, 2016 and December 31, 2015 . Rental property (in thousands) March 31, 2016 December 31, 2015 Land $ 229,288 $ 228,919 Buildings, net of accumulated depreciation of $110,783 and $104,297, respectivel y 1,227,133 1,232,360 Tenant improvements, net of accumulated depreciation of $27,262 and $26,283, respectively 21,902 23,586 Building and land improvements, net of accumulated depreciation of $22,775 and $19,815, respectivel y 74,635 74,694 Construction in progress 4,932 1,658 Deferred leasing intangibles, net of accumulated amortization of $209,898 and $200,758, respectively 263,867 276,272 Total rental property, net $ 1,821,757 $ 1,837,489
Schedule of real estate properties acquired	The following tables summarize the acquisitions of the Company during the three months ended March 31, 2016 . Location of property Square Feet Buildings Purchase Price (in thousands) Biddeford, ME 265,126 2 $ 12,452 Fairfield, OH 206,448 1 5,330 Mascot, TN 130,560 1 4,500 Erlanger, KY 108,620 1 5,600 Three months ended March 31, 2016 710,754 5 $ 27,882
Summary of allocation of the consideration paid for the acquired assets and liabilities in connection with the acquisition of buildings at the date of acquisition	The following table summarizes the allocation of the consideration paid at the date of acquisition during the three months ended March 31, 2016 for the acquired assets and liabilities in connection with the acquisitions identified in the table above. Acquired assets and liabilities Purchase price (in thousands) Weighted average amortization period (years) of intangibles at acquisition Land $ 3,236 N/A Buildings 15,879 N/A Tenant improvements 138 N/A Building and land improvements 2,042 N/A Deferred leasing intangibles - In-place leases 3,990 4.5 Deferred leasing intangibles - Tenant relationships 2,541 7.4 Deferred leasing intangibles - Above market leases 245 3.9 Deferred leasing intangibles - Below market leases (189 ) 5.2 Total purchase price $ 27,882
Schedule of pro forma information for acquired properties	The table below sets forth the results of operations for the properties acquired during the three months ended March 31, 2016 , included in the Company’s Consolidated Statements of Operations from the date of acquisition. Results of operations (in thousands) Three months ended March 31, 2016 Revenue $ 127 Property acquisition costs $ 521 Net income $ 576 The following tables set forth pro forma information for the three months ended March 31, 2016 and March 31, 2015 , respectively. The below pro forma information does not purport to represent what the actual results of operations of the Company would have been had the acquisitions outlined above occurred on the first day of the applicable reporting period, nor do they purport to predict the results of operations of future periods. The pro forma information has not been adjusted for property sales. Pro Forma (in thousands) (1) Three months ended March 31, 2016 Total revenue $ 61,309 Net income $ 12,954 (2) Net income attributable to common stockholders $ 9,428 Pro Forma (in thousands) (3) Three months ended March 31, 2015 Total revenue $ 53,112 Net loss $ 2,300 (2) Net loss attributable to common stockholders $ 4,873 (1) The unaudited pro forma information for the three months ended March 31, 2016 is presented as if the properties acquired during the three months ended March 31, 2016 had occurred at January 1, 2015, the beginning of the reporting period prior to acquisition. (2) The net income for the three months ended March 31, 2016 excludes approximately $0.5 million of property acquisition costs related to the acquisition of buildings that closed during the three months ended March 31, 2016 , and the net loss for the three months ended March 31, 2015 was adjusted to include these acquisition costs. Net loss for the three months ended March 31, 2015 excludes approximately $0.2 million of property acquisition costs related to the acquisition of buildings that closed during the three months ended March 31, 2015 . (3) The unaudited pro forma information for the three months ended March 31, 2015 is presented as if the properties acquired during the three months ended March 31, 2016 and the properties acquired during the three months ended March 31, 2015 had occurred at January 1, 2015 and January 1, 2014, respectively, the beginning of the reporting period prior to acquisition.
Disposal Groups, Including Discontinued Operations	The following table summarizes the dispositions of the Company during the three months ended March 31, 2016 (in thousands, except for square feet and building count). All of the dispositions were accounted for under the full accrual method. Location of property Square Feet Buildings Carrying Value Sales Price Net Proceeds Gain on Sale Wichita, KS (1) 44,760 1 Gresham, OR (2) 420,690 1 Canton, OH (3) 398,000 1 Orangeburg, SC (4) 319,000 1 Three months ended March 31, 2016 1,182,450 4 $ 14,217 $ 32,800 $ 31,890 $ 17,673 (1) The building contributed approximately $0 and $0 to total revenue and approximately $34,000 (exclusive of the gain on sale of rental property and loss on extinguishment of debt) and $26,000 of net loss to the net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (2) The building contributed approximately $0.3 million and $0.4 million to total revenue and approximately ($8,000) (exclusive of the gain on sale of rental property and loss on extinguishment of debt) and $39,000 to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (3) The building contributed approximately $0.3 million and $0.5 million to total revenue and approximately $0.1 million (exclusive of the gain on the sale of rental property) and ($17,000) to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively. (4) The building contributed approximately $0.2 million and $0.3 million to total revenue and approximately $0.2 million (exclusive of the gain on sale of rental property) and $0.1 million to net income (loss) of the Company during the three months ended March 31, 2016 and March 31, 2015 , respectively.
Schedule of Finite-Lived Intangible Assets and Below Market Leases	The following table summarizes the deferred leasing intangibles on the accompanying Consolidated Balance Sheets as of March 31, 2016 and December 31, 2015 . March 31, 2016 December 31, 2015 Deferred Leasing Intangibles (in thousands) Gross Accumulated Amortization Net Gross Accumulated Amortization Net Above market leases $ 68,850 $ (32,879 ) $ 35,971 $ 69,815 $ (31,554 ) $ 38,261 Other intangible lease assets 404,915 (177,019 ) 227,896 407,215 (169,204 ) 238,011 Total deferred leasing intangible assets $ 473,765 $ (209,898 ) $ 263,867 $ 477,030 $ (200,758 ) $ 276,272 Below market leases $ 19,344 $ (8,514 ) $ 10,830 $ 19,923 $ (8,536 ) $ 11,387 Total deferred leasing intangible liabilities $ 19,344 $ (8,514 ) $ 10,830 $ 19,923 $ (8,536 ) $ 11,387 The following table sets forth the amortization expense and the net decrease to rental revenue for the amortization of deferred leasing intangibles during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, Deferred Leasing Intangibles Amortization (in thousands) 2016 2015 Net decrease to rental revenue related to above and below market lease amortization $ 1,666 $ 2,064 Amortization expense related to other intangible lease assets $ 15,913 $ 14,275
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The following table sets forth the amortization of deferred leasing intangibles over the next five years as of March 31, 2016 . Year Amortization Expense Related to Other Intangible Lease Assets (in thousands) Net Decrease to Rental Revenue Related to Above and Below Market Lease Amortization (in thousands) Remainder of 2016 $ 44,659 $ 4,695 2017 $ 50,687 $ 4,796 2018 $ 40,003 $ 3,557 2019 $ 29,529 $ 3,242 2020 $ 22,463 $ 3,078
Below Market Lease, Future Amortization Income	The following table sets forth the amortization of deferred leasing intangibles over the next five years as of March 31, 2016 . Year Amortization Expense Related to Other Intangible Lease Assets (in thousands) Net Decrease to Rental Revenue Related to Above and Below Market Lease Amortization (in thousands) Remainder of 2016 $ 44,659 $ 4,695 2017 $ 50,687 $ 4,796 2018 $ 40,003 $ 3,557 2019 $ 29,529 $ 3,242 2020 $ 22,463 $ 3,078

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Summary of the mortgage notes payable, unsecured term loans and credit facility	The following table sets forth a summary of the Company’s outstanding indebtedness, including borrowings under the Company’s unsecured credit facility, unsecured term loans, unsecured notes and mortgage notes as of March 31, 2016 and December 31, 2015 . Loan Principal outstanding as of March 31, 2016 (in thousands) Principal outstanding as of December 31, 2015 (in thousands) Interest (1) Current Maturity Prepayment Terms (2) Unsecured credit facility: Unsecured Credit Facility (3) $ 6,000 $ 56,000 L + 1.20% Dec-18-2019 i Total unsecured credit facility 6,000 56,000 Unsecured term loans: Unsecured Term Loan C (4) — — L + 1.35% Sep-29-2020 i Unsecured Term Loan B 150,000 150,000 L + 1.75% Mar-21-2021 ii Unsecured Term Loan A 150,000 150,000 L + 1.80% Mar-31-2022 ii Total unsecured term loans 300,000 300,000 Less: Total unamortized debt issuance costs 221 231 Total carrying value unsecured term loans 299,779 299,769 Unsecured notes: Series F Unsecured Notes 100,000 100,000 3.98 % Jan-05-2023 ii Series A Unsecured Notes 50,000 50,000 4.98 % Oct-1-2024 ii Series D Unsecured Notes 100,000 100,000 4.32 % Feb-20-2025 ii Series B Unsecured Notes 50,000 50,000 4.98 % Jul-1-2026 ii Series C Unsecured Notes 80,000 80,000 4.42 % Dec-30-2026 ii Series E Unsecured Notes 20,000 20,000 4.42 % Feb-20-2027 ii Total unsecured notes 400,000 400,000 Less: Total unamortized debt issuance costs 616 634 Total carrying value unsecured notes 399,384 399,366 Mortgage notes (secured debt): Sun Life Assurance Company of Canada (U.S.) — 3,229 6.05 % Jun-1-2016 iii Webster Bank, National Association 5,471 5,513 4.22 % Aug-4-2016 iii National Life Insurance Company 4,732 4,775 5.75 % Aug-10-2016 iii Union Fidelity Life Insurance Co. 5,663 5,754 5.81 % Apr-30-2017 iv Principal Life Insurance Company 5,632 5,676 5.73 % May-05-2017 iii Webster Bank, National Association 2,923 2,945 3.66 % May-29-2017 iii Webster Bank, National Association 3,148 3,172 3.64 % May-31-2017 iii Wells Fargo, National Association 4,097 4,115 5.90 % Aug-1-2017 v Connecticut General Life Insurance Company-1 Facility 56,942 57,171 6.50 % Feb-1-2018 vi Connecticut General Life Insurance Company-2 Facility 47,345 58,085 5.75 % Feb-1-2018 vi Connecticut General Life Insurance Company-3 Facility 16,338 16,401 5.88 % Feb-1-2018 vi Wells Fargo Bank, National Association CMBS Loan 62,315 63,897 4.31 % Dec-1-2022 vii Total mortgage notes 214,606 230,733 Add: Total unamortized fair market value premiums 325 447 Less: Total unamortized debt issuance costs 204 243 Total carrying value mortgage notes 214,727 230,937 Total / weighted average interest rate (5) $ 919,890 $ 986,072 4.24 % (1) Current interest rate as of March 31, 2016 . At March 31, 2016 , the one-month LIBOR (“L”) was 0.43725% . The current interest rate is not adjusted to include the amortization of deferred financing fees or debt issuance costs incurred in obtaining debt or the unamortized fair market value premiums. The spread over the applicable rate for the Company's unsecured credit facility and unsecured term loans is based on the Company's consolidated leverage ratio, as defined in the respective loan agreements. (2) Prepayment terms consist of (i) pre-payable with no penalty; (ii) pre-payable with penalty; (iii) pre-payable without penalty three months prior to the maturity date; (iv) pre-payable without penalty two months prior to the maturity date; (v) pre-payable without penalty three months prior to the maturity date, however can be defeased; (vi) pre-payable without penalty six months prior to the maturity date; and (vii) pre-payable without penalty three months prior to the maturity date, however can be defeased beginning January 1, 2016. (3) The capacity of the unsecured credit facility is $450.0 million . (4) Capacity of $150.0 million , in which the Company has until September 29, 2016 to draw the full amount. (5) The weighted average interest rate was calculated using the fixed interest rate swapped on the current notional amount of $300.0 million of debt, and is not adjusted to include the amortization of deferred financing fees or debt issuance costs incurred in obtaining debt or the unamortized fair market value premiums.
Schedule of aggregate carrying value of the debt and the corresponding estimate of fair value	The following table presents the aggregate principal outstanding of the Company’s debt and the corresponding estimate of fair value as of March 31, 2016 and December 31, 2015 (in thousands). March 31, 2016 December 31, 2015 Principal Outstanding Fair Value Principal Outstanding Fair Value Unsecured credit facility $ 6,000 $ 5,978 $ 56,000 $ 56,000 Unsecured term loans 300,000 304,923 300,000 303,457 Unsecured notes 400,000 409,980 400,000 392,054 Mortgage notes 214,606 220,597 230,733 237,327 Total principal amount 920,606 $ 941,478 986,733 $ 988,838 Add: Total unamortized fair market value premiums 325 447 Less: Total unamortized debt issuance costs 1,041 1,108 Total carrying value $ 919,890 $ 986,072

Use of Derivative Financial I22

Use of Derivative Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of interest rate swaps	The following table details the Company’s outstanding interest rate swaps as of March 31, 2016 . Interest Rate Trade Date Effective Date Notional Amount (in thousands) Fair Value (in thousands) Pay Fixed Interest Rate Receive Variable Interest Rate Maturity Date PNC Bank, N.A. Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 Bank of America, N.A. Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 UBS AG Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 Royal Bank of Canada Sep-14-2012 Oct-10-2012 $ 10,000 $ (25 ) 0.7945 % One-month L Sep-10-2017 RJ Capital Services, Inc. Sep-14-2012 Oct-10-2012 $ 10,000 $ (26 ) 0.7975 % One-month L Sep-10-2017 Bank of America, N.A. Sep-20-2012 Oct-10-2012 $ 25,000 $ (48 ) 0.7525 % One-month L Sep-10-2017 RJ Capital Services, Inc. Sep-24-2012 Oct-10-2012 $ 25,000 $ (39 ) 0.7270 % One-month L Sep-10-2017 Regions Bank Mar-01-2013 Mar-01-2013 $ 25,000 $ (411 ) 1.3300 % One-month L Feb-14-2020 Capital One, N.A. Jun-13-2013 Jul-01-2013 $ 50,000 $ (1,480 ) 1.6810 % One-month L Feb-14-2020 Capital One, N.A. Jun-13-2013 Aug-01-2013 $ 25,000 $ (761 ) 1.7030 % One-month L Feb-14-2020 Regions Bank Sep-30-2013 Feb-03-2014 $ 25,000 $ (1,037 ) 1.9925 % One-month L Feb-14-2020 The Toronto-Dominion Bank Oct-14-2015 Sep-29-2016 $ 25,000 $ (329 ) 1.3830 % One-month L Sep-29-2020 PNC Bank, N.A. Oct-14-2015 Sep-29-2016 $ 50,000 $ (674 ) 1.3906 % One-month L Sep-29-2020 Regions Bank Oct-14-2015 Sep-29-2016 $ 35,000 $ (475 ) 1.3858 % One-month L Sep-29-2020 U.S. Bank, N.A. Oct-14-2015 Sep-29-2016 $ 25,000 $ (339 ) 1.3950 % One-month L Sep-29-2020 Capital One, N.A. Oct-14-2015 Sep-29-2016 $ 15,000 $ (205 ) 1.3950 % One-month L Sep-29-2020 Royal Bank of Canada Jan-08-2015 Mar-20-2015 $ 25,000 $ (809 ) 1.7090 % One-month L Mar-21-2021 The Toronto-Dominion Bank Jan-08-2015 Mar-20-2015 $ 25,000 $ (805 ) 1.7105 % One-month L Mar-21-2021 The Toronto-Dominion Bank Jan-08-2015 Sep-10-2017 $ 100,000 $ (3,346 ) 2.2255 % One-month L Mar-21-2021 Wells Fargo Bank, N.A. Jan-08-2015 Mar-20-2015 $ 25,000 $ (944 ) 1.8280 % One-month L Mar-31-2022 The Toronto-Dominion Bank Jan-08-2015 Feb-14-2020 $ 25,000 $ (359 ) 2.4535 % One-month L Mar-31-2022 Regions Bank Jan-08-2015 Feb-14-2020 $ 50,000 $ (756 ) 2.4750 % One-month L Mar-31-2022 Capital One, N.A. Jan-08-2015 Feb-14-2020 $ 50,000 $ (789 ) 2.5300 % One-month L Mar-31-2022 The fair value of the interest rate swaps outstanding as of March 31, 2016 and December 31, 2015 was as follows: Balance Sheet Line Item (in thousands) Notional Amount March 31, 2016 Fair Value March 31, 2016 Notional Amount December 31, 2015 Fair Value December 31, 2015 Interest rate swaps-Asset $ — $ — $ 275,000 $ 1,867 Interest rate swaps-Liability $ 675,000 $ (13,732 ) $ 400,000 $ (3,766 )
Schedule of the location in the financial statements of the gain or loss recognized on interest rate swaps	The table below details the location in the financial statements of the gain or loss recognized on interest rate swaps designated as cash flow hedges for the three months ended March 31, 2016 and March 31, 2015 , (in thousands). Three Months Ended March 31, 2016 2015 Amount of loss recognized in accumulated other comprehensive income (loss) on interest rate swaps (effective portion) $ 12,568 $ 4,671 Amount of loss reclassified from accumulated other comprehensive income (loss) into income as interest expense (effective portion) $ 745 $ 666 Amount of gain (loss) recognized in interest expense (ineffective portion and amount excluded from effectiveness testing) $ — $ —
Schedule of financial instruments accounted for at fair value on a recurring basis	The following sets forth the Company’s financial instruments that are accounted for at fair value on a recurring basis as of March 31, 2016 and December 31, 2015 . Fair Value Measurements as of Balance Sheet Line Item (in thousands) Fair Value March 31, 2016 Level 1 Level 2 Level 3 Interest rate swaps-Asset $ — $ — $ — $ — Interest rate swaps-Liability $ (13,732 ) $ — $ (13,732 ) $ — Fair Value Measurements as of Balance Sheet Line Item (in thousands) Fair Value December 31, 2015 Level 1 Level 2 Level 3 Interest rate swaps-Asset $ 1,867 $ — $ 1,867 $ — Interest rate swaps-Liability $ (3,766 ) $ — $ (3,766 ) $ —

Equity (Tables)

Equity (Tables)	3 Months Ended
	Mar. 31, 2016
Stockholders' Equity Note [Abstract]
Schedule of Stock by Class	The table below sets forth the Company’s outstanding preferred stock issuances as of March 31, 2016 . Preferred Stock Issuances Issuance Date Number of Shares Price and Liquidation Value per share Interest Rate Series A Preferred Stock November 2, 2011 2,760,000 $ 25.00 9.000 % Series B Preferred Stock April 16, 2013 2,800,000 $ 25.00 6.625 % Series C Preferred Stock March 17, 2016 3,000,000 $ 25.00 6.875 %
Schedule of dividends	The tables below set forth the dividends attributable to the Preferred Stock Issuance s during the three months ended March 31, 2016 and the year ended December 31, 2015 : Quarter Ended 2016 Declaration Date Series A Series B Payment Date March 31 February 22, 2016 $ 0.5625 $ 0.4140625 March 31, 2016 Total $ 0.5625 $ 0.4140625 Quarter Ended 2015 Declaration Date Series A Series B Payment Date December 31 October 22, 2015 $ 0.5625 $ 0.4140625 December 31, 2015 September 30 July 21, 2015 0.5625 0.4140625 September 30, 2015 June 30 May 4, 2015 0.5625 0.4140625 June 30, 2015 March 31 February 20, 2015 0.5625 0.4140625 March 31, 2015 Total $ 2.2500 $ 1.6562500 The table below sets forth the dividends attributable to the common stock during the three months ended March 31, 2016 and the year ended December 31, 2015 . Month Ended 2016 Declaration Date Record Date Per Share Payment Date June 30 February 22, 2016 June 30, 2016 $ 0.115833 July 15, 2016 May 31 February 22, 2016 May 31, 2016 0.115833 June 15, 2016 April 30 February 22, 2016 April 29, 2016 0.115833 May 16, 2016 March 31 October 22, 2015 March 31, 2016 0.115833 April 15, 2016 February 29 October 22, 2015 February 29, 2016 0.115833 March 15, 2016 January 31 October 22, 2015 January 29, 2016 0.115833 February 16, 2016 Total $ 0.694998 Month Ended 2015 Declaration Date Record Date Per Share Payment Date December 31 July 21, 2015 December 31, 2015 $ 0.1150 January 15, 2016 November 30 July 21, 2015 November 30, 2015 0.1150 December 15, 2015 October 31 July 21, 2015 October 30, 2015 0.1150 November 16, 2015 September 30 May 4, 2015 September 30, 2015 0.1150 October 15, 2015 August 31 May 4, 2015 August 31, 2015 0.1150 September 15, 2015 July 31 May 4, 2015 July 31, 2015 0.1150 August 17, 2015 June 30 February 20, 2015 June 30, 2015 0.1125 July 15, 2015 May 31 February 20, 2015 May 29, 2015 0.1125 June 15, 2015 April 30 February 20, 2015 April 30, 2015 0.1125 May 15, 2015 March 31 October 30, 2014 March 31, 2015 0.1125 April 15, 2015 February 28 October 30, 2014 February 27, 2015 0.1125 March 16, 2015 January 31 October 30, 2014 January 31, 2015 0.1125 February 17, 2015 Total $ 1.3650
Schedule of stock sale activity	The following sets forth the Company’s at-the market ("ATM") common stock offering program as of March 31, 2016 . Once the ATM offering program is associated with the Company’s most recent shelf registration statement, the Company may from time to time sell its common stock through sales agents under the program. ATM Stock Offering Program (in thousands) Date Maximum Aggregate Offering Price Aggregate Common Stock Available as of March 31, 2016 2014 $200 million ATM September 10, 2014 $ 200,000 $ 107,380 The table below sets forth the activity for the ATM common stock offering programs during the year ended December 31, 2015 (in thousands, except share data). There was no activity for the ATM common stock offering programs during three months ended March 31, 2016 . Year ended December 31, 2015 ATM Stock Offering Program Shares Weighted Average Price Per Share Gross Sales Net 2014 $200 million ATM 2,661,403 $ 21.63 $ 57,571 $ 864 $ 56,707 2014 $150 million ATM 795,000 $ 21.79 17,321 260 17,061 Total/weighted average 3,456,403 $ 21.67 $ 74,892 $ 1,124 $ 73,768
Schedule of activity related to unvested restricted stock awards	The following table summarizes activity related to the Company’s unvested restricted shares of common stock for the three months ended March 31, 2016 and the year ended December 31, 2015 . Unvested restricted shares of common stock Shares Balance at December 31, 2014 263,916 Granted 94,290 (1) Vested (72,185 ) Forfeited (14,906 ) Balance at December 31, 2015 271,115 Granted 101,289 (2) Vested (84,336 ) Forfeited (552 ) Balance at March 31, 2016 287,516 (1) The grant date fair value per share was $26.17 . (2) The grant date fair value per share was $17.98 .
Schedule of fair value at vesting date for awards vesting during the period	The following table summarizes the fair value at vesting date for the restricted shares of common stock vested during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, 2016 2015 Vested restricted shares of common stock 84,336 57,528 Fair value of vested restricted shares of common stock (in thousands) $ 1,522 $ 1,425

Noncontrolling Interest (Tables

Noncontrolling Interest (Tables)	3 Months Ended
	Mar. 31, 2016
Noncontrolling Interest [Abstract]
Noncontrolling interest activity	The table below summarizes the activity for noncontrolling interest in the Company for the three months ended March 31, 2016 and the year ended December 31, 2015 . LTIP Units Other Common Units Total Noncontrolling Common Units Noncontrolling Interest Balance at December 31, 2014 1,307,036 1,124,813 2,431,849 3.6 % Granted/Issued 323,069 864,283 1,187,352 N/A Forfeitures — — — N/A Conversions from LTIP units to Other Common Units (20,000 ) 20,000 — N/A Redemptions from Other Common Units to common stock — (90,824 ) (90,824 ) N/A Redemption of Other Common Units for cash — (2,400 ) (2,400 ) N/A Balance at December 31, 2015 1,610,105 1,915,872 3,525,977 4.9 % Granted/Issued 176,396 — 176,396 N/A Forfeitures — — — N/A Balance at March 31, 2016 1,786,501 1,915,872 3,702,373 5.2 %
Schedule of assumptions for valuing units issued	The table below sets forth the assumptions used in valuing such LTIP units for the three months ended March 31, 2016 . Assumptions Grant date February 22, 2016 January 8, 2016 January 6, 2016 Expected term (years) 10 10 10 Expected volatility 22.0 % 22.0 % 22.0 % Expected dividend yield 6.0 % 6.0 % 6.0 % Risk-free interest rate 1.01 % 1.28 % 1.36 % Fair value of LTIP units at issuance (in thousands) $ 277 $ 2,254 $ 390 LTIP units at issuance 18,386 135,546 22,464 Fair value unit price per LTIP unit at issuance $ 15.07 $ 16.63 $ 17.36
Schedule of activity related to share-based compensation	The following table summarizes activity related to the Company’s unvested LTIP units for the three months ended March 31, 2016 and the year ended December 31, 2015 . Unvested LTIP units LTIP Units Balance at December 31, 2014 448,887 Granted 323,069 Vested (237,046 ) Forfeited — Balance at December 31, 2015 534,910 Granted 176,396 Vested (170,277 ) Forfeited — Balance at March 31, 2016 541,029 The following table summarizes the fair value at vesting date for the LTIP units vested during the three months ended March 31, 2016 and March 31, 2015 . Three months ended March 31, 2016 2015 Vested LTIP units 170,277 51,420 Fair value of vested LTIP units (in thousands) $ 3,089 $ 1,209

Equity Incentive Plan (Tables)

Equity Incentive Plan (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Equity Compensation Expense	The following table summarizes the amount recorded in general and administrative expenses in the accompanying Consolidated Statements of Operations for the amortization of restricted shares of common stock, LTIP units, the OPP, performance units, and the Company’s board of directors’ compensation. Three months ended March 31, Non-cash compensation expense (in thousands) 2016 2015 Restricted stock $ 558 $ 492 LTIP units 2,795 (1) 1,137 Outperformance program 119 131 Performance units 53 — Board of directors compensation (2) 80 87 Total non-cash compensation expense $ 3,605 $ 1,847 (1) Inclusive of approximately of $1.6 million non-cash compensation expense during the three months ended March 31, 2016 associated with the severance cost of an executive officer as discussed Note 7. (2) All of the Company’s independent directors elected to receive shares of common stock in lieu of cash for their service during the three months ended March 31, 2016 and March 31, 2015 . The number of shares of common stock granted is calculated based on the trailing 10 days average common stock price ending on the third business day preceding the grant date.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Schedule of computation of basic and diluted earnings per common share	The following tables set forth the computation of basic and diluted earnings per common share for the three months ended March 31, 2016 and March 31, 2015 . Earnings per share (in thousands, except share data) Three months ended March 31, 2016 Numerator Net income $ 11,801 Less: preferred stock dividends 2,912 Less: amount allocated to participating securities 100 Less: income attributable to noncontrolling interest after preferred stock dividends 455 Net income attributable to common stockholders $ 8,334 Denominator Weighted average common shares outstanding — basic 67,889,217 Weighted average common shares outstanding — diluted 67,964,559 Income per share — basic and diluted Income from continuing operations attributable to common stockholders - basic $ 0.12 Income from continuing operations attributable to common stockholders - diluted $ 0.12 Earnings per share (in thousands, except share data) Three months ended March 31, 2015 Numerator Net loss $ (1,427 ) Less: preferred stock dividends 2,712 Less: amount allocated to participating securities 101 Less: loss attributable to noncontrolling interest after preferred stock dividends (198 ) Net loss attributable to common stockholders $ (4,042 ) Denominator Weighted average common shares outstanding—basic and diluted 64,286,213 Loss per share - basic and diluted $ (0.06 )

Organization and Description 27

Organization and Description of Business (Details) ft² in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2016ft²tenantstatebuilding	Dec. 31, 2015
Real Estate Properties [Line Items]
Ownership interest in Operating Partnership (as a percent)	94.80%	95.10%
Number of properties	292
Number of states in which the entity owned buildings | state	38
Area (in square feet) | ft²	54.3
Percentage of buildings leased to tenants	94.80%
Number of tenants | tenant	260
Warehouse - Distribution buildings
Real Estate Properties [Line Items]
Number of properties	224
Light Manufacturing buildings
Real Estate Properties [Line Items]
Number of properties	47
Flex - Office buildings
Real Estate Properties [Line Items]
Number of properties	21

Summary of Significant Accoun28

Summary of Significant Accounting Policies - Reclassifications and New Accounting Pronouncements (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred financing fees, net	$ 8.4	$ 8.9
Accounting Standards Updated 2015-03 | Loans Payable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred financing fees, net		0.2
Accounting Standards Updated 2015-03 | Notes Payable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred financing fees, net		0.6
Accounting Standards Updated 2015-03 | Secured Debt
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred financing fees, net		0.2
Accounting Standards Updated 2015-03 | Prepaid Expenses and Other Assets
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred financing fees, net		$ (1.1)

Summary of Significant Accoun29

Summary of Significant Accounting Policies - Tenant Accounts Receivable (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Tenant Accounts Receivable, net
Lease security deposits available in existing letters of credit	$ 6.1	$ 6.1
Cash and Cash Equivalents
Tenant Accounts Receivable, net
Security deposit	4.2	4.1
Restricted Cash
Tenant Accounts Receivable, net
Security deposit	0.4	0.4
Prepaid Rent
Tenant Accounts Receivable, net
Lease security deposits available in cash	4.6
Security Deposits
Tenant Accounts Receivable, net
Lease security deposits available in cash		4.5
Prepaid Expenses and Other Assets
Tenant Accounts Receivable, net
Due from related parties	0.1	0.1
Tenant Receivable
Tenant Accounts Receivable, net
Allowance for doubtful accounts	0.1	0.1
Accrued Rental Income
Tenant Accounts Receivable, net
Allowance for doubtful accounts	0	0
Accrued rental revenue	$ 16.6	$ 16.1

Summary of Significant Accoun30

Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Oct. 20, 2015	Mar. 31, 2015
Dayton, OH, Q4 2007
Revenue Recognition
Lease termination fee receivable		$ 200
Dayton, OH, Q4 2007 | Rental income
Revenue Recognition
Lease termination fee income	$ 54
Payment Guarantee
Revenue Recognition
Estimated amount of real estate taxes, which are the responsibility of tenants	$ 2,600		$ 2,500

Summary of Significant Accoun31

Summary of Significant Accounting Policies - Taxes (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Business Acquisition [Line Items]
Net income (loss)	$ 11,801,000	$ (1,427,000)
State and local income, excise and franchise taxes	200,000	200,000
Liabilities for uncertain tax positions	0		$ 0
Real Estate Investment Trust
Business Acquisition [Line Items]
Net income (loss)	$ (11,000)	$ 0

Real Estate - Summary (Details)

Real Estate - Summary (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	$ 1,821,757	$ 1,837,489
Land
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	229,288	228,919
Building
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	1,227,133	1,232,360
Rental property, accumulated depreciation	110,783	104,297
Tenant improvements
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	21,902	23,586
Rental property, accumulated depreciation	27,262	26,283
Building and land improvements
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	74,635	74,694
Rental property, accumulated depreciation	22,775	19,815
Construction in progress
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	4,932	1,658
Deferred leasing intangibles
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	263,867	276,272
Rental property, accumulated depreciation	$ 209,898	$ 200,758

Real Estate - Acquisitions (Det

Real Estate - Acquisitions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)ft²building
Business Acquisition [Line Items]
Area (in square feet)	54,300,000
Biddeford, ME
Business Acquisition [Line Items]
Area (in square feet)	265,126
Number of buildings acquired | building	2
Purchase price | $	$ 12,452
Fairfield, OH
Business Acquisition [Line Items]
Area (in square feet)	206,448
Number of buildings acquired | building	1
Purchase price | $	$ 5,330
Mascot, TN
Business Acquisition [Line Items]
Area (in square feet)	130,560
Number of buildings acquired | building	1
Purchase price | $	$ 4,500
Erlanger, KY
Business Acquisition [Line Items]
Area (in square feet)	108,620
Number of buildings acquired | building	1
Purchase price | $	$ 5,600
Acquisitions Q1 2016
Business Acquisition [Line Items]
Area (in square feet)	710,754
Number of buildings acquired | building	5
Purchase price | $	$ 27,882

Real Estate - Acquisitions - Al

Real Estate - Acquisitions - Allocation of Consideration (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)
In-place leases
Allocation of the consideration paid for the acquired assets and liabilities
Deferred leasing intangibles	$ 3,990
Acquisitions Q1 2016
Allocation of the consideration paid for the acquired assets and liabilities
Land	3,236
Buildings	15,879
Tenant improvements	138
Building and land Improvements	2,042
Below market leases	(189)
Total purchase price	$ 27,882
Weighted average amortization period of below market leases	5 years 2 months 15 days
Acquisitions Q1 2016 | In-place leases
Allocation of the consideration paid for the acquired assets and liabilities
Weighted average amortization period of lease intangibles	4 years 5 months 15 days
Acquisitions Q1 2016 | Tenant relationships
Allocation of the consideration paid for the acquired assets and liabilities
Deferred leasing intangibles	$ 2,541
Weighted average amortization period of lease intangibles	7 years 4 months 15 days
Acquisitions Q1 2016 | Above market leases
Allocation of the consideration paid for the acquired assets and liabilities
Deferred leasing intangibles	$ 245
Weighted average amortization period of lease intangibles	3 years 10 months 15 days

Real Estate - Acquisitions - Pr

Real Estate - Acquisitions - Pro Forma (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Business Acquisition [Line Items]
Property acquisition costs	$ 552	$ 318
Acquisitions Q1 2016
Business Acquisition [Line Items]
Revenue	127
Property acquisition costs	521
Net income (loss)	576
Pro forma information
Total revenue	61,309
Net loss	12,954
Net loss attributable to common stockholders	9,428
Acquisitions Q1 2015
Pro forma information
Total revenue		53,112
Net loss		2,300
Net loss attributable to common stockholders		4,873
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Property acquisition costs	$ 500	$ 200

Real Estate - Disposals (Detail

Real Estate - Disposals (Details)	3 Months Ended
	Mar. 31, 2016USD ($)ft²propertybuilding	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	54,300,000
Carrying value of property sold	$ 1,821,757,000		$ 1,837,489,000
Disposal Group, Held-for-sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties held-for-sale | property	2
Q1 2016 Disposals | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	1,182,450
Number of buildings disposed | building	4
Carrying value of property sold	$ 14,217,000
Sales price	32,800,000
Net proceeds from sales of rental property	31,890,000
Gain (Loss) on Sale	$ 17,673,000
Wichita, KS | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	44,760
Number of buildings disposed | building	1
Contribution to revenue	$ 0	$ 0
Net income (loss) before gain on sale of rental property	$ (34,000)	(26,000)
Gresham, OR | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	420,690
Number of buildings disposed | building	1
Contribution to revenue	$ 300,000	400,000
Net income (loss) before gain on sale of rental property	$ (8,000)	39,000
Canton, OH | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	398,000
Number of buildings disposed | building	1
Contribution to revenue	$ 300,000	500,000
Net income (loss) before gain on sale of rental property	$ 100,000	(17,000)
Orangeburg, SC | Disposal Group, Disposed of by Sale, Not Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area (in square feet) | ft²	319,000
Number of buildings disposed | building	1
Contribution to revenue	$ 200,000	300,000
Net income (loss) before gain on sale of rental property	$ 200,000	$ 100,000

Real Estate- Deferred Leasing I

Real Estate- Deferred Leasing Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Above market lease, gross	$ 473,765		$ 477,030
Deferred leasing intangibles assets, accumulated amortization	(209,898)		(200,758)
Above market lease, net	263,867		276,272
Below market lease, gross	19,344		19,923
Below market lease, accumulated amortization	(8,514)		(8,536)
Below market lease, net	10,830		11,387
Net decrease to rental revenue related to above and below market lease amortization	1,666	$ 2,064
Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract]
Remainder of 2016	4,695
2,017	4,796
2,018	3,557
2,019	3,242
2,020	3,078
Above market leases
Finite-Lived Intangible Assets [Line Items]
Above market lease, gross	68,850		69,815
Deferred leasing intangibles assets, accumulated amortization	(32,879)		(31,554)
Above market lease, net	35,971		38,261
Other intangible lease assets
Finite-Lived Intangible Assets [Line Items]
Above market lease, gross	404,915		407,215
Deferred leasing intangibles assets, accumulated amortization	(177,019)		(169,204)
Above market lease, net	227,896		$ 238,011
Amortization expense related to other intangible lease assets	15,913	$ 14,275
Estimated Net Amortization of In-Place Leases, Leasing Commissions and Tenant Relationships
Remainder of 2016	44,659
2,017	50,687
2,018	40,003
2,019	29,529
2,020	$ 22,463

Debt - Summary (Details)

Debt - Summary (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Principal outstanding	$ 919,890,000	$ 986,072,000
Unamortized debt issuance costs	$ 1,000,000	1,100,000
Weighted average interest rate	4.24%
Interest Rate Swaps
Debt Instrument [Line Items]
Notional amount	$ 300,000,000
One Month LIBOR
Debt Instrument [Line Items]
Variable rate basis reference rate (as a percent)	0.43725%
Secured Debt
Debt Instrument [Line Items]
Principal outstanding	$ 214,727,000	230,937,000
Long-term debt, gross	214,606,000	230,733,000
Unamortized debt issuance costs	204,000	243,000
Unamortized fair market value premium	325,000	447,000
Term Loan | Unsecured Debt
Debt Instrument [Line Items]
Principal outstanding	299,779,000	299,769,000
Long-term debt, gross	300,000,000	300,000,000
Unamortized debt issuance costs	221,000	231,000
$150 Million Wells Fargo Unsecured Term Loan C | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	0	0
Face amount of debt	$ 150,000,000
$150 Million Wells Fargo Unsecured Term Loan C | Unsecured Debt | LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	1.35%
$150 Million Wells Fargo Unsecured Term Loan B | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 150,000,000	150,000,000
$150 Million Wells Fargo Unsecured Term Loan B | Unsecured Debt | LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	1.75%
$150 Million Wells Fargo Unsecured Term Loan A | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 150,000,000	150,000,000
$150 Million Wells Fargo Unsecured Term Loan A | Unsecured Debt | LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	1.80%
Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Principal outstanding	$ 399,384,000	399,366,000
Long-term debt, gross	400,000,000	400,000,000
Unamortized debt issuance costs	616,000	634,000
$100 Million Series F Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000,000	100,000,000
Stated interest rate	3.98%
$50 Million Series A Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,000,000	50,000,000
Stated interest rate	4.98%
$100 Million Series D Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 100,000,000	100,000,000
Stated interest rate	4.32%
$50 Million Series B Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 50,000,000	50,000,000
Stated interest rate	4.98%
$80 Million Series C Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 80,000,000	80,000,000
Stated interest rate	4.42%
$20 Million Series E Unsecured Notes | Unsecured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 20,000,000	20,000,000
Stated interest rate	4.42%
Sun Life Assurance Company of Canada (U.S) Due June 1, 2016 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 0	3,229,000
Stated interest rate	6.05%
Webster Bank, National Association due August 4, 2016 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,471,000	5,513,000
Stated interest rate	4.22%
National Life Insurance Company Due August 10, 2016 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 4,732,000	4,775,000
Stated interest rate	5.75%
Union Fidelity Life Insurance Co Due April 30, 2017 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,663,000	5,754,000
Stated interest rate	5.81%
Penalty free prepayment period	2 months
Principal Life Insurance Company Due May 05, 2017 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 5,632,000	5,676,000
Stated interest rate	5.73%
Webster Bank, National Association due May 29, 2017 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 2,923,000	2,945,000
Stated interest rate	3.66%
Webster Bank, National Association due May 31, 2017 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 3,148,000	3,172,000
Stated interest rate	3.64%
Wells Fargo, National Association Due August 1, 2017 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 4,097,000	4,115,000
Stated interest rate	5.90%
Penalty free prepayment period	3 months
Connecticut General Life Insurance Company - Facility 1 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 56,942,000	57,171,000
Stated interest rate	6.50%
Connecticut General Life Insurance Company - Facility 2 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 47,345,000	58,085,000
Stated interest rate	5.75%
Connecticut General Life Insurance Company - Facility 3 | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 16,338,000	16,401,000
Stated interest rate	5.88%
Wells Fargo Bank, National Association CMBS Loan | Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	$ 62,315,000	63,897,000
Stated interest rate	4.31%
Penalty free prepayment period	3 months
Sun Life Assurance Company Of Canada, Webster Bank National Association, and Principal LIfe Insurance Company | Secured Debt
Debt Instrument [Line Items]
Penalty free prepayment period	3 months
Connecticut General Life Insurance Company Facilities | Secured Debt
Debt Instrument [Line Items]
Penalty free prepayment period	6 months
Line of Credit | Unsecured Debt
Debt Instrument [Line Items]
Principal outstanding	$ 6,000,000	56,000,000
Line of Credit | $450 Million Wells Fargo Unsecured Credit Facility | Unsecured Debt
Debt Instrument [Line Items]
Principal outstanding	6,000,000	$ 56,000,000
Maximum borrowing capacity	$ 450,000,000
Line of Credit | $450 Million Wells Fargo Unsecured Credit Facility | Unsecured Debt | LIBOR
Debt Instrument [Line Items]
Interest rate margin (as a percent)	1.20%

Debt - 2016 Activity (Details)

Debt - 2016 Activity (Details) - USD ($) $ in Thousands	Mar. 17, 2016	Mar. 03, 2016	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Unused borrowing capacity			$ 594,000
Deferred financing fees, net			8,400		$ 8,900
Unamortized debt issuance costs			1,000		1,100
Amortization of deferred financing fees			500	$ 300
Secured Debt
Debt Instrument [Line Items]
Unamortized debt issuance costs			204		243
Connecticut General Life Insurance Company - Facility 2 | Secured Debt
Debt Instrument [Line Items]
Extinguishment of debt amount	$ 10,500
Write off of deferred debt issuance cost			900
Wells Fargo Bank, National Association CMBS Loan | Secured Debt
Debt Instrument [Line Items]
Extinguishment of debt amount		$ 1,200
Write off of deferred debt issuance cost			200
Sun Life Assurance Company of Canada (U.S) Due June 1, 2016 | Secured Debt
Debt Instrument [Line Items]
Write off of deferred debt issuance cost			17
Prepaid Expenses and Other Assets
Debt Instrument [Line Items]
Interest payable			$ 5,500		$ 3,800

Debt - Fair Value (Details)

Debt - Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 1,000	$ 1,100
Principal outstanding	919,890	986,072
Unsecured Debt | Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	300,000	300,000
Unamortized debt issuance costs	221	231
Principal outstanding	299,779	299,769
Unsecured Debt | Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	400,000	400,000
Unamortized debt issuance costs	616	634
Principal outstanding	399,384	399,366
Unsecured Debt | Line of Credit
Debt Instrument [Line Items]
Principal outstanding	6,000	56,000
Secured Debt
Debt Instrument [Line Items]
Long-term debt, gross	214,606	230,733
Unamortized fair market value premium	325	447
Unamortized debt issuance costs	204	243
Principal outstanding	214,727	230,937
Carrying Amount
Debt Instrument [Line Items]
Long-term debt, gross	920,606	986,733
Unamortized fair market value premium	325	447
Unamortized debt issuance costs	1,041	1,108
Principal outstanding	919,890	986,072
Carrying Amount | Unsecured Debt | Term Loan
Debt Instrument [Line Items]
Long-term debt, gross	300,000	300,000
Carrying Amount | Unsecured Debt | Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, gross	400,000	400,000
Carrying Amount | Unsecured Debt | Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross	6,000	56,000
Carrying Amount | Secured Debt | Mortgages
Debt Instrument [Line Items]
Long-term debt, gross	214,606	230,733
Level 3 Inputs | Fair Value
Debt Instrument [Line Items]
Long-term debt, fair value	941,478	988,838
Level 3 Inputs | Fair Value | Unsecured Debt | Term Loan
Debt Instrument [Line Items]
Long-term debt, fair value	304,923	303,457
Level 3 Inputs | Fair Value | Unsecured Debt | Unsecured Notes
Debt Instrument [Line Items]
Long-term debt, fair value	409,980	392,054
Level 3 Inputs | Fair Value | Unsecured Debt | Line of Credit
Debt Instrument [Line Items]
Long-term debt, fair value	5,978	56,000
Level 3 Inputs | Fair Value | Secured Debt | Mortgages
Debt Instrument [Line Items]
Long-term debt, fair value	$ 220,597	$ 237,327
Minimum | Level 3 Inputs | Long-term Debt | Income Approach Valuation Technique
Debt Instrument [Line Items]
Discount rate at which cash flows are discounted (as a percent)	1.74%	1.58%
Maximum | Level 3 Inputs | Long-term Debt | Income Approach Valuation Technique
Debt Instrument [Line Items]
Discount rate at which cash flows are discounted (as a percent)	4.19%	4.82%

Use of Derivative Financial I41

Use of Derivative Financial Instruments - Risk Management and Unsecured Loan Swaps (Details)	Mar. 31, 2016USD ($)
Interest Rate Swaps
Unsecured Term Loan Swaps
Notional amount	$ 300,000,000
Interest Rate Derivative, PNC Bank, October 10, 2012
Unsecured Term Loan Swaps
Notional amount	10,000,000
Fair value	$ (25,000)
Fixed Interest Rate (as a percent)	0.7945%
Interest Rate Derivative, Bank of America, October 10, 2012
Unsecured Term Loan Swaps
Notional amount	$ 10,000,000
Fair value	$ (25,000)
Fixed Interest Rate (as a percent)	0.7945%
Interest Rate Derivative, UBS AG, October 10, 2012
Unsecured Term Loan Swaps
Notional amount	$ 10,000,000
Fair value	$ (25,000)
Fixed Interest Rate (as a percent)	0.7945%
Interest Rate Derivative, Royal Bank of Canada, October 10, 2012
Unsecured Term Loan Swaps
Notional amount	$ 10,000,000
Fair value	$ (25,000)
Fixed Interest Rate (as a percent)	0.7945%
Interest Rate Derivative, RJ Capital Services, Inc, October 10, 2012, One
Unsecured Term Loan Swaps
Notional amount	$ 10,000,000
Fair value	$ (26,000)
Fixed Interest Rate (as a percent)	0.7975%
Interest Rate Derivative, Bank of America, October 10, 2012, Two
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (48,000)
Fixed Interest Rate (as a percent)	0.7525%
Interest Rate Derivative, RJ Capital Services, October 10, 2012, Two
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (39,000)
Fixed Interest Rate (as a percent)	0.727%
Interest Rate Derivative, Regions Bank, March 01, 2013
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (411,000)
Fixed Interest Rate (as a percent)	1.33%
Interest Rate Derivative, Capital One, June 01, 2013
Unsecured Term Loan Swaps
Notional amount	$ 50,000,000
Fair value	$ (1,480,000)
Fixed Interest Rate (as a percent)	1.681%
Interest Rate Derivative, Capital One, August 01, 2013
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (761,000)
Fixed Interest Rate (as a percent)	1.703%
Interest Rate Derivative, Regions Bank, February 03, 2014
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (1,037,000)
Fixed Interest Rate (as a percent)	1.9925%
Interest Rate Derivative, The Toronto-Dominion Bank, September 29, 2016
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (329,000)
Fixed Interest Rate (as a percent)	1.383%
Interest Rate Derivative, PNC Bank, September 29, 2016
Unsecured Term Loan Swaps
Notional amount	$ 50,000,000
Fair value	$ (674,000)
Fixed Interest Rate (as a percent)	1.3906%
Interest Rate Derivative, Regions Bank, September 29, 2016
Unsecured Term Loan Swaps
Notional amount	$ 35,000,000
Fair value	$ (475,000)
Fixed Interest Rate (as a percent)	1.3858%
Interest Rate Derivative, US Bank, September 29, 2016
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (339,000)
Fixed Interest Rate (as a percent)	1.395%
Interest Rate Derivative, Capital One, September 29, 2016
Unsecured Term Loan Swaps
Notional amount	$ 15,000,000
Fair value	$ (205,000)
Fixed Interest Rate (as a percent)	1.395%
Interest Rate Derivative, Royal Bank of Canada, March 20, 2015
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (809,000)
Fixed Interest Rate (as a percent)	1.709%
Interest Rate Derivative, The Toronto-Dominion Bank, March 20, 2015
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (805,000)
Fixed Interest Rate (as a percent)	1.7105%
Interest Rate Derivative, The Toronto-Dominion Bank, September 10, 2017
Unsecured Term Loan Swaps
Notional amount	$ 100,000,000
Fair value	$ (3,346,000)
Fixed Interest Rate (as a percent)	2.2255%
Interest Rate Derivative, Wells Fargo Bank, March 20, 2015
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (944,000)
Fixed Interest Rate (as a percent)	1.828%
Interest Rate Derivative, The Toronto-Dominion Bank, February 14, 2020
Unsecured Term Loan Swaps
Notional amount	$ 25,000,000
Fair value	$ (359,000)
Fixed Interest Rate (as a percent)	2.4535%
Interest Rate Derivative, Regions Bank, February 14, 2020
Unsecured Term Loan Swaps
Notional amount	$ 50,000,000
Fair value	$ (756,000)
Fixed Interest Rate (as a percent)	2.475%
Interest Rate Derivative, Capital One, February 14, 2020
Unsecured Term Loan Swaps
Notional amount	$ 50,000,000
Fair value	$ (789,000)
Fixed Interest Rate (as a percent)	2.53%

Use of Derivative Financial I42

Use of Derivative Financial Instruments - FV of Interest Rate Swaps (Details) - Interest Rate Swaps - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Fair value of the interest rate swaps outstanding
Notional amount assets	$ 0	$ 275,000
Fair value - assets	0	1,867
Notional amount liabilities	675,000	400,000
Fair Value - liabilities	$ (13,732)	$ (3,766)

Use of Derivative Financial I43

Use of Derivative Financial Instruments - Cash Flow Hedges and Contingent Features (Details) - Interest Rate Swaps $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)derivative	Mar. 31, 2015USD ($)
Cash Flow Hedges of Interest Rate Risk
Additional amount reclassified from accumulated other comprehensive income (loss) as an increase to interest expense over the next twelve months	$ 3,100
Amount of income (loss) recognized in accumulated other comprehensive income (loss) on interest rate swaps (effective portion)	12,568	$ 4,671
Amount of loss reclassified from accumulated other comprehensive income (loss) into income (loss) as interest expense (effective portion)	745	666
Amount of gain (loss) recognized in interest expense (ineffective portion and amount excluded from effectiveness testing)	$ 0	$ 0
Credit-risk-related Contingent Features
Number of interest rate swaps in liability position | derivative	23
Fair values of the interest rate swaps in a net liability position	$ 14,600
Value of adjustment for nonperformance risk related to net liability position	900
Termination value required to settle obligations under agreements	14,800
Accounts Payable, Accrued Expenses and Other Liabilities
Credit-risk-related Contingent Features
Accrued interest on interest rate swaps	$ 100

Use of Derivative Financial I44

Use of Derivative Financial Instruments - FV on Recurring Basis (Details) - Interest Rate Swaps - Fair value on recurring basis - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Assets (liabilities):
Interest rate swaps-Asset	$ 0	$ 1,867
Interest rate swaps-Liability	(13,732)	(3,766)
Level 1
Assets (liabilities):
Interest rate swaps-Asset	0	0
Interest rate swaps-Liability	0	0
Level 2
Assets (liabilities):
Interest rate swaps-Asset	0	1,867
Interest rate swaps-Liability	(13,732)	(3,766)
Level 3
Assets (liabilities):
Interest rate swaps-Asset	0	0
Interest rate swaps-Liability	$ 0	$ 0

Equity - Preferred Stock (Detai

Equity - Preferred Stock (Details) - $ / shares	May. 02, 2016	Mar. 31, 2016	Feb. 22, 2016	Dec. 31, 2015	Oct. 22, 2015	Sep. 30, 2015	Jul. 21, 2015	Jun. 30, 2015	May. 04, 2015	Mar. 31, 2015	Feb. 20, 2015	Mar. 31, 2016	Dec. 31, 2015
Class of Stock [Line Items]
Preferred stock, shares authorized		15,000,000		10,000,000								15,000,000	10,000,000
Preferred stock, par value (in dollars per share)		$ 0.01		$ 0.01								$ 0.01	$ 0.01
Series C Preferred Stock
Class of Stock [Line Items]
Number of shares sold												3,000,000
Issue price (in dollars per share)		25										$ 25
Dividend rate (as a percent)												6.875%
Series C Preferred Stock | Non-recognized Subsequent Event
Class of Stock [Line Items]
Dividend declared (in dollars per share)	$ 0.49653
Series B Preferred Stock
Class of Stock [Line Items]
Number of shares sold												2,800,000
Issue price (in dollars per share)		25										$ 25
Dividend rate (as a percent)												6.625%
Dividend declared (in dollars per share)			$ 0.4140625		$ 0.4140625		$ 0.4140625		$ 0.4140625		$ 0.4140625	$ 0.4140625	1.65625
Dividends paid (in dollars per share)		0.4140625		0.4140625		$ 0.4140625		$ 0.4140625		$ 0.4140625		$ 0.4140625	1.65625
Series B Preferred Stock | Non-recognized Subsequent Event
Class of Stock [Line Items]
Dividend declared (in dollars per share)	0.4140625
Series A Preferred Stock
Class of Stock [Line Items]
Number of shares sold												2,760,000
Issue price (in dollars per share)		25										$ 25
Dividend rate (as a percent)												9.00%
Dividend declared (in dollars per share)			$ 0.5625		$ 0.5625		$ 0.5625		$ 0.5625		$ 0.5625	$ 0.5625	2.25
Dividends paid (in dollars per share)		$ 0.5625		$ 0.5625		$ 0.5625		$ 0.5625		$ 0.5625		$ 0.5625	$ 2.25
Series A Preferred Stock | Non-recognized Subsequent Event
Class of Stock [Line Items]
Dividend declared (in dollars per share)	$ 0.5625

Equity - Common Stock (Details)

Equity - Common Stock (Details) - USD ($)	Jul. 15, 2016	Jun. 15, 2016	May. 16, 2016	May. 02, 2016	Apr. 15, 2016	Mar. 15, 2016	Feb. 22, 2016	Feb. 16, 2016	Jan. 15, 2016	Dec. 15, 2015	Nov. 16, 2015	Oct. 22, 2015	Oct. 15, 2015	Sep. 15, 2015	Aug. 17, 2015	Jul. 21, 2015	Jul. 15, 2015	Jun. 15, 2015	May. 15, 2015	May. 04, 2015	Apr. 15, 2015	Mar. 16, 2015	Feb. 20, 2015	Feb. 17, 2015	Oct. 30, 2014	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Class of Stock [Line Items]
Proceeds from sales of common stock																										$ 0	$ 10,133,000
Common Stock
Class of Stock [Line Items]
Dividend declared (in dollars per share)							$ 0.115833					$ 0.115833				$ 0.115				$ 0.115			$ 0.1125		$ 0.1125	$ 0.694998		$ 1.365
Dividends paid (in dollars per share)						$ 0.115833		$ 0.115833	$ 0.115	$ 0.115	$ 0.115		$ 0.115	$ 0.115	$ 0.115		$ 0.1125	$ 0.1125	$ 0.1125		$ 0.1125	$ 0.1125		$ 0.1125		$ 0.694998		$ 1.365
Common Stock | Non-recognized Subsequent Event
Class of Stock [Line Items]
Dividend declared (in dollars per share)				$ 0.115833
Dividends paid (in dollars per share)					$ 0.115833
Common Stock | Non-recognized Subsequent Event | Scenario, Forecast
Class of Stock [Line Items]
Dividends paid (in dollars per share)	$ 0.115833	$ 0.115833	$ 0.115833
2014 $200 million ATM | Common Stock
Class of Stock [Line Items]
Maximum aggregate offering price under at-the-market program																										$ 200,000,000
Aggregate value of common stock available to be sold under the ATM																										107,380,000
Number of shares sold																												2,661,403
Proceeds from sales of common stock																												$ 57,571,000
Sales agents' fee																												864,000
Net proceeds																												$ 56,707,000
2014 $150 million ATM | Common Stock
Class of Stock [Line Items]
Maximum aggregate offering price under at-the-market program																										$ 150,000,000
Number of shares sold																												795,000
Proceeds from sales of common stock																												$ 17,321,000
Sales agents' fee																												260,000
Net proceeds																												$ 17,061,000
At The Market (ATM) Program | Common Stock
Class of Stock [Line Items]
Number of shares sold																										0		3,456,403
Proceeds from sales of common stock																												$ 74,892,000
Sales agents' fee																												1,124,000
Net proceeds																												$ 73,768,000
Weighted Average | 2014 $200 million ATM | Common Stock
Class of Stock [Line Items]
Issue price (in dollars per share)																												$ 21.63
Weighted Average | 2014 $150 million ATM | Common Stock
Class of Stock [Line Items]
Issue price (in dollars per share)																												21.79
Weighted Average | At The Market (ATM) Program | Common Stock
Class of Stock [Line Items]
Issue price (in dollars per share)																												$ 21.67

Equity - Restricted Stock (Deta

Equity - Restricted Stock (Details) - 2011 Equity Incentive Plan - Restricted stock $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016USD ($)installment$ / sharesshares	Mar. 31, 2015USD ($)shares	Dec. 31, 2015$ / sharesshares
Shares
Unvested at beginning of period (in shares)	271,115	263,916	263,916
Granted (in shares)	101,289		94,290
Vested (in shares)	(84,336)	(57,528)	(72,185)
Forfeited (in shares)	(552)		(14,906)
Unvested at end of period (in shares)	287,516		271,115
Grant date fair value (in dollars per share) | $ / shares	$ 17.98		$ 26.17
Unrecognized compensation costs | $	$ 4,900
Number of shares vested	84,336	57,528	72,185
Fair value of shares vested | $	$ 1,522	$ 1,425
Unrecognized compensation costs, period for recognition	2 years 8 months 13 days
Granted on January 8, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equal vesting installments | installment	4

Noncontrolling Interest (Detail

Noncontrolling Interest (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015	Dec. 31, 2014
Noncontrolling interest
Noncontrolling interest ownership percentage	5.20%		4.90%	3.60%
LTIP Units | 2011 Equity Incentive Plan
Summary of nonvested share-based compensation activity
Unvested at beginning of period (in shares)	534,910	448,887	448,887
Granted (in shares)	176,396		323,069
Vested (in shares)	(170,277)	(51,420)	(237,046)
Forfeited (in shares)	0		0
Unvested at end of period (in shares)	541,029		534,910
Fair value of shares vested	$ 3,089	$ 1,209
Noncontrolling Interest - Unit holders in Operating Partnership
Noncontrolling interest
Units outstanding, balance at beginning of period (in units)	3,525,977	2,431,849	2,431,849
Granted/Issued (in units)	176,396		1,187,352
Forfeitures (in units)	0		0
Conversions from LTIP units to Other Common Units (in units)			0
Redemptions from Other Common Units to common stock (in units)			(90,824)
Redemption of Other Common Units for cash (in units)			(2,400)
Units outstanding, balance at end of period (in units)	3,702,373		3,525,977
LTIP Units | Noncontrolling Interest - Unit holders in Operating Partnership
Noncontrolling interest
Units outstanding, balance at beginning of period (in units)	1,610,105	1,307,036	1,307,036
Granted/Issued (in units)	176,396		323,069
Forfeitures (in units)	0		0
Conversions from LTIP units to Other Common Units (in units)			(20,000)
Redemptions from Other Common Units to common stock (in units)			0
Redemption of Other Common Units for cash (in units)			0
Units outstanding, balance at end of period (in units)	1,786,501		1,610,105
Other Common Units | Noncontrolling Interest - Unit holders in Operating Partnership
Noncontrolling interest
Units outstanding, balance at beginning of period (in units)	1,915,872	1,124,813	1,124,813
Granted/Issued (in units)	0		864,283
Forfeitures (in units)	0		0
Conversions from LTIP units to Other Common Units (in units)			20,000
Redemptions from Other Common Units to common stock (in units)			(90,824)
Redemption of Other Common Units for cash (in units)			(2,400)
Units outstanding, balance at end of period (in units)	1,915,872		1,915,872

Noncontrolling Interest - LTIP

Noncontrolling Interest - LTIP Units Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)shares	Mar. 31, 2015USD ($)
Other Common Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit conversion ratio	1
Redemption right of investor to cause the Operating Partnership to redeem its units equivalent to current market value of number of shares of entity's common stock (in shares) | shares	1
General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 3,605	$ 1,847
Geoffrey G. Jervis | General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Salary, bonus and other benefits	1,500
LTIP Units | General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	2,795	$ 1,137
2011 Equity Incentive Plan | LTIP Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs	$ 9,900
Unrecognized compensation costs, period for recognition	3 years
2011 Equity Incentive Plan | LTIP Units | Geoffrey G. Jervis | General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 1,600
Awards vest over five years | 2011 Equity Incentive Plan | LTIP Units | Executive officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit conversion ratio	1
Awards vest over five years | 2011 Equity Incentive Plan | LTIP Units | Executive officers | Other Common Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	10 days
Grant Date January 8, 2016 | Awards vest over five years | 2011 Equity Incentive Plan | LTIP Units | Executive officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Grant Date February 22, 2016 | Awards vest over three years | 2011 Equity Incentive Plan | LTIP Units | Executive officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Awarded in 2015 | 2011 Equity Incentive Plan | LTIP Units | Geoffrey G. Jervis | General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation	$ 1,600

Noncontrolling Interest - FV As

Noncontrolling Interest - FV Assumptions (Details) - LTIP Units - 2011 Equity Incentive Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Assumptions
Units at issuance (in shares)	176,396	323,069
Grant Date February 22, 2016
Assumptions
Expected term	10 years
Expected volatility (as a percent)	22.00%
Expected dividend yield (as a percent)	6.00%
Risk-free interest rate (as a percent)	1.01%
Fair value of units at issuance	$ 277
Units at issuance (in shares)	18,386
Fair value share price per unit (in dollars per share)	$ 15.07
Grant Date January 8, 2016
Assumptions
Expected term	10 years
Expected volatility (as a percent)	22.00%
Expected dividend yield (as a percent)	6.00%
Risk-free interest rate (as a percent)	1.28%
Fair value of units at issuance	$ 2,254
Units at issuance (in shares)	135,546
Fair value share price per unit (in dollars per share)	$ 16.63
Grant Date January 6, 2016
Assumptions
Expected term	10 years
Expected volatility (as a percent)	22.00%
Expected dividend yield (as a percent)	6.00%
Risk-free interest rate (as a percent)	1.36%
Fair value of units at issuance	$ 390
Units at issuance (in shares)	22,464
Fair value share price per unit (in dollars per share)	$ 17.36

Equity Incentive Plan - Summary

Equity Incentive Plan - Summary (Details) - 2011 Equity Incentive Plan - Performance shares $ in Millions	Mar. 08, 2016USD ($)benchmark	Mar. 31, 2016USD ($)
Awarded in 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Measurement period for outperformance pool plan threshold	3 years
Number of benchmarks | benchmark	3
Allocation for Company TSR compared to industry peer group	25.00%
Allocation for Company TSR compared to size-based peer group	25.00%
Allocation for Company TSR compared to MSCI US REIT index	50.00%
Value of awards	$ 2.6
Unrecognized compensation costs		$ 2.6
Unrecognized compensation costs, period for recognition		3 years 2 months
Awarded in 2016 | Vest immediately after measurement period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percent	50.00%
Awarded in 2016 | Vest one year after measurement period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percent	50.00%
Vesting period (in years)	1 year
Awarded in 2016 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of target units awarded	0.00%
Awarded in 2016 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of target units awarded	250.00%
Awarded in 2016 | Weighted Average
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility (as a percent)	23.00%
Risk-free interest rate (as a percent)	1.0849%
Expected dividend yield (as a percent)	6.00%
Awarded in 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs		$ 0.8
Unrecognized compensation costs, period for recognition		1 year 9 months 20 days

Equity Incentive Plan - Equity

Equity Incentive Plan - Equity Non-cash Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
2011 Equity Incentive Plan | Common Stock
Equity Incentive Plan
Number of days of average trailing stock price used to calculate number of shares of common stock granted	10 days
General and Administrative Expenses
Equity Incentive Plan
Share-based compensation	$ 3,605	$ 1,847
General and Administrative Expenses | Independent Director
Equity Incentive Plan
Share-based compensation	80	87
General and Administrative Expenses | Restricted stock
Equity Incentive Plan
Share-based compensation	558	492
General and Administrative Expenses | LTIP Units
Equity Incentive Plan
Share-based compensation	2,795	1,137
General and Administrative Expenses | LTIP Units | Geoffrey G. Jervis | 2011 Equity Incentive Plan
Equity Incentive Plan
Share-based compensation	1,600
General and Administrative Expenses | LTIP Units | Awarded in 2015 | Geoffrey G. Jervis | 2011 Equity Incentive Plan
Equity Incentive Plan
Share-based compensation	1,600
General and Administrative Expenses | Performance shares | Awarded in 2015
Equity Incentive Plan
Share-based compensation	119	131
General and Administrative Expenses | Performance shares | Awarded in 2016
Equity Incentive Plan
Share-based compensation	$ 53	$ 0

Earnings Per Share (Details)

Earnings Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Antidilutive participating securities
Unvested shares of restricted stock on a weighted average basis excluded from computation of earnings per share (in shares)		0
Restricted stock
Antidilutive participating securities
Participating securities	285,458	290,280
Unvested shares of restricted stock on a weighted average basis excluded from computation of earnings per share (in shares)	43,529
Performance shares
Antidilutive participating securities
Unvested shares of restricted stock on a weighted average basis excluded from computation of earnings per share (in shares)	31,813

Earnings Per Share - Reconcilia

Earnings Per Share - Reconciliation of Numerator and Denominator (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Numerator
Net income (loss) from continuing operations	$ 11,801	$ (1,427)
Less: preferred stock dividends	2,912	2,712
Less: amount allocated to participating securities	100	101
Less: loss attributable to noncontrolling interest after preferred stock dividends	455	(198)
Net income (loss) attributable to common stockholders	$ 8,334	$ (4,042)
Denominator
Weighted average common shares outstanding — basic (in shares)	67,889,217	64,286,213
Weighted average common shares outstanding — diluted (in shares)	67,964,559	64,286,213
Weighted average common shares outstanding - basic and diluted (in shares)		64,286,213
Income (loss) from continuing operations attributable to common stockholders - basic (in dollars per share)	$ 0.12	$ (0.06)
Income (loss) from continuing operations attributable to common stockholders - diluted (in dollars per share)	$ 0.12	(0.06)
Loss per share - basic and diluted (in dollars per share)		$ (0.06)

Commitments and Contingencies -

Commitments and Contingencies - Agreements (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Business Acquisition, Contingent Consideration [Line Items]
Letters of credit outstanding	$ 3,400,000
Property Acquisition under Agreement with Columbus Nova | Incentive Fee
Business Acquisition, Contingent Consideration [Line Items]
Fair value of incentive fee	$ 0	$ 0
Property Acquisition under Agreement with Columbus Nova | Incentive Fee | Level 3 Inputs | Market And Income Approach Valuation Technique | Contingent Consideration
Business Acquisition, Contingent Consideration [Line Items]
Discount rate at which cash flows are discounted (as a percent)	9.50%
Fair value inputs, exit capitalization rate (as a percent)	9.80%