Retail Properties of America (RPAI) 10-Q 2 Nov 16 2016 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2016	Oct. 28, 2016
Entity Information [Line Items]
Entity Registrant Name	RETAIL PROPERTIES OF AMERICA, INC.
Entity Central Index Key	1,222,840
Document Type	10-Q
Document Period End Date	Sep. 30, 2016
Amendment Flag	false
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		237,374,540

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Investment properties:
Land	$ 1,235,929	$ 1,254,131
Building and other improvements	4,333,989	4,428,554
Developments in progress	5,860	5,157
Gross investment properties	5,575,778	5,687,842
Less accumulated depreciation	(1,460,799)	(1,433,195)
Net investment properties	4,114,979	4,254,647
Cash and cash equivalents	69,071	51,424
Accounts and notes receivable (net of allowances of $6,277 and $7,910, respectively)	79,943	82,804
Acquired lease intangible assets, net	137,310	138,766
Assets associated with investment properties held for sale	3,581	0
Other assets, net	108,117	93,610
Total assets	4,513,001	4,621,251
Liabilities:
Mortgages payable, net	1,000,089	1,123,136
Unsecured notes payable, net	595,479	495,576
Unsecured term loans, net	447,302	447,526
Unsecured revolving line of credit	0	100,000
Accounts payable and accrued expenses	67,141	69,800
Distributions payable	39,315	39,297
Acquired lease intangible liabilities, net	105,211	114,834
Liabilities associated with investment properties held for sale	36	0
Other liabilities	76,444	75,745
Total liabilities	2,331,017	2,465,914
Commitments and contingencies (Note 14)
Equity:
Additional paid-in capital	4,934,381	4,931,395
Accumulated distributions in excess of earnings	(2,752,743)	(2,776,215)
Accumulated other comprehensive income (loss)	104	(85)
Total equity	2,181,984	2,155,337
Total liabilities and equity	4,513,001	4,621,251
7.00% Series A cumulative redeemable preferred stock
Equity:
Preferred stock	5	5
Class A common stock
Equity:
Class A common stock	$ 237	$ 237

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Accounts and notes receivable, allowances (in dollars)	$ 6,277	$ 7,910
7.00% Series A cumulative redeemable preferred stock
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000	10,000
Preferred stock, dividend rate	7.00%	7.00%
Preferred stock, shares issued	5,400	5,400
Preferred stock, shares outstanding	5,400	5,400
Preferred stock, liquidation preference	$ 135,000	$ 135,000
Class A common stock
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	475,000	475,000
Common stock, shares issued	237,376	237,267
Common stock, shares outstanding	237,376	237,267

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Other Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues
Rental income	$ 113,627	$ 116,715	$ 344,081	$ 355,525
Tenant recovery income	29,130	28,901	89,140	89,617
Other property income	1,769	5,339	7,170	9,898
Total revenues	144,526	150,955	440,391	455,040
Expenses
Operating expenses	20,285	22,741	63,438	71,589
Real estate taxes	19,937	20,961	60,966	61,957
Depreciation and amortization	56,763	52,871	163,602	163,345
Provision for impairment of investment properties	4,742	169	11,048	4,113
General and administrative expenses	11,110	10,939	33,289	35,949
Total expenses	112,837	107,681	332,343	336,953
Operating income	31,689	43,274	108,048	118,087
Gain on extinguishment of debt	0	0	13,653	0
Gain on extinguishment of other liabilities	0	0	6,978	0
Interest expense	(25,602)	(40,425)	(78,343)	(110,610)
Other income, net	22	479	449	1,398
Income from continuing operations	6,109	3,328	50,785	8,875
Gain on sales of investment properties	66,385	75,001	97,737	113,214
Net income	72,494	78,329	148,522	122,089
Preferred stock dividends	(2,362)	(2,362)	(7,087)	(7,087)
Net income attributable to common shareholders	$ 70,132	$ 75,967	$ 141,435	$ 115,002
Earnings per common share – basic and diluted
Net income per common share attributable to common shareholders	$ 0.30	$ 0.32	$ 0.60	$ 0.49
Net income	$ 72,494	$ 78,329	$ 148,522	$ 122,089
Other comprehensive income:
Net unrealized gain on derivative instruments (Note 9)	666	155	189	157
Comprehensive income attributable to the Company	$ 73,160	$ 78,484	$ 148,711	$ 122,246
Weighted average number of common shares outstanding – basic	236,783	236,439	236,692	236,348
Weighted average number of common shares outstanding – diluted	237,108	236,553	236,983	236,400

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Preferred stock7.00% Series A cumulative redeemable preferred stock	Common stockClass A common stock	Additional paid-in capital	Accumulated distributions in excess of earnings	Accumulated other comprehensive (loss) income	Total shareholders' equity	Noncontrolling interests
Balance at Dec. 31, 2014	$ 2,189,375	$ 5	$ 237	$ 4,922,864	$ (2,734,688)	$ (537)	$ 2,187,881	$ 1,494
Balance (in shares) at Dec. 31, 2014		5,400	236,602
Increase (decrease) in shareholders' equity
Net income	122,089				122,089		122,089
Other comprehensive income	157					157	157
Distributions declared to preferred shareholders	(7,087)				(7,087)		(7,087)
Distributions declared to common shareholders	(117,876)				(117,876)		(117,876)
Issuance of common stock, net of offering costs	(111)			(111)			(111)
Issuance of restricted shares (in shares)			801
Stock-based compensation expense, net of forfeitures	8,225			8,225			8,225
Stock-based compensation expense, net of forfeitures (in shares)			(4)
Shares withheld for employee taxes	(1,723)			(1,723)			(1,723)
Shares withheld for employee taxes (in shares)			(112)
Balance at Sep. 30, 2015	2,193,049	$ 5	$ 237	4,929,255	(2,737,562)	(380)	2,191,555	1,494
Balance (in shares) at Sep. 30, 2015		5,400	237,287
Increase (decrease) in shareholders' equity
Cumulative effect of accounting change				17	(17)
Balance at Dec. 31, 2015	2,155,337	$ 5	$ 237	4,931,395	(2,776,215)	(85)	2,155,337	0
Balance (in shares) at Dec. 31, 2015		5,400	237,267
Increase (decrease) in shareholders' equity
Net income	148,522				148,522		148,522
Other comprehensive income	189					189	189
Distributions declared to preferred shareholders	(7,087)				(7,087)		(7,087)
Distributions declared to common shareholders	(117,946)				(117,946)		(117,946)
Issuance of common stock, net of offering costs	(100)			(100)			(100)
Issuance of restricted shares (in shares)			269
Exercise of stock options	23			23			23
Exercise of stock options (in shares)			2
Stock-based compensation expense, net of forfeitures	5,296			5,296			5,296
Stock-based compensation expense, net of forfeitures (in shares)			(10)
Shares withheld for employee taxes	(2,250)			(2,250)			(2,250)
Shares withheld for employee taxes (in shares)			(152)
Balance at Sep. 30, 2016	$ 2,181,984	$ 5	$ 237	$ 4,934,381	$ (2,752,743)	$ 104	$ 2,181,984	$ 0
Balance (in shares) at Sep. 30, 2016		5,400	237,376

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Equity (parenthetical) - $ / shares	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Distributions declared to preferred shareholders (in dollars per share)	$ 1.3125	$ 1.3125
Distributions declared to common shareholders (in dollars per share)	$ 0.496875	$ 0.496875

Condensed Consolidated Stateme7

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 148,522	$ 122,089
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	163,602	163,345
Provision for impairment of investment properties	11,048	4,113
Gain on sales of investment properties	(97,737)	(113,214)
Gain on extinguishment of debt	(13,653)	0
Gain on extinguishment of other liabilities	(6,978)	0
Amortization of loan fees and debt premium and discount, net	4,372	3,881
Amortization of stock-based compensation	5,296	8,225
Premium paid in connection with defeasance of mortgages payable	0	16,285
Payment of leasing fees and inducements	(7,730)	(6,151)
Changes in accounts receivable, net	(1,109)	6,820
Changes in accounts payable and accrued expenses, net	803	2,325
Changes in other operating assets and liabilities, net	(637)	2,930
Other, net	(791)	(1,572)
Net cash provided by operating activities	205,008	209,076
Cash flows from investing activities:
Changes in restricted escrows, net	(5,904)	21,268
Purchase of investment properties	(266,377)	(407,857)
Capital expenditures and tenant improvements	(43,207)	(35,565)
Proceeds from sales of investment properties	307,355	395,207
Investment in developments in progress	(315)	(1,019)
Other, net	194	(26)
Net cash used in investing activities	(8,254)	(27,992)
Cash flows from financing activities:
Proceeds from mortgages payable	0	967
Principal payments on mortgages payable	(45,244)	(346,164)
Proceeds from unsecured notes payable	100,000	248,815
Proceeds from unsecured credit facility	390,000	550,000
Repayments of unsecured credit facility	(490,000)	(420,000)
Payment of loan fees and deposits, net	(6,386)	(2,237)
Purchase of U.S. Treasury securities in connection with defeasance of mortgages payable	0	(81,547)
Distributions paid	(125,015)	(124,849)
Other, net	(2,462)	(1,823)
Net cash used in financing activities	(179,107)	(176,838)
Net increase in cash and cash equivalents	17,647	4,246
Cash and cash equivalents, at beginning of period	51,424	112,292
Cash and cash equivalents, at end of period	69,071	116,538
Supplemental cash flow disclosure, including non-cash activities:
Cash paid for interest, net of interest capitalized	73,603	86,054
Distributions payable	39,315	39,301
Accrued capital expenditures and tenant improvements	7,740	5,875
Accrued leasing fees and inducements	913	532
Amounts reclassified to developments in progress	2,467	0
Developments in progress placed in service	0	2,288
U.S. Treasury securities transferred in connection with defeasance of mortgages payable	0	81,547
Defeasance of mortgages payable	0	65,262
Purchase of investment properties (after credits at closing):
Land, building and other improvements, net	(261,657)	(400,484)
Accounts receivable, acquired lease intangibles and other assets	(25,049)	(41,450)
Accounts payable, acquired lease intangibles and other liabilities	5,013	34,077
Mortgages payable assumed, net	15,316	0
Purchase of investment properties (after credits at closing)	(266,377)	(407,857)
Proceeds from sales of investment properties:
Land, building and other improvements, net	282,661	279,559
Accounts receivable, acquired lease intangibles and other assets	15,306	6,583
Accounts payable, acquired lease intangibles and other liabilities	(9,149)	(4,181)
Deferred gain	1,500	32
Mortgage debt forgiven or assumed	(94,353)	0
Gain on extinguishment of debt	13,653	0
Gain on sales of investment properties	97,737	113,214
Proceeds from sales of investment properties	$ 307,355	$ 395,207

Organization and Basis of Prese

Organization and Basis of Presentation	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	ORGANIZATION AND BASIS OF PRESENTATION Retail Properties of America, Inc. (the Company) was formed on March 5, 2003 and its primary purpose is to own and operate high quality, strategically located shopping centers in the United States. The Company has elected to be taxed as a real estate investment trust (REIT) under the Internal Revenue Code of 1986, as amended (the Code). The Company believes it qualifies for taxation as a REIT and, as such, the Company generally will not be subject to U.S. federal income tax on taxable income that is distributed to its shareholders. If the Company fails to qualify as a REIT in any taxable year, the Company will be subject to U.S. federal income tax on its taxable income. Even if the Company qualifies for taxation as a REIT, the Company may be subject to certain state and local taxes on its income, property or net worth and U.S. federal income and excise taxes on its undistributed income. The Company has one wholly-owned subsidiary that has jointly elected to be treated as a taxable REIT subsidiary (TRS) and is subject to U.S. federal, state and local income taxes at regular corporate tax rates. The income tax expense incurred by the TRS did not have a material impact on the Company’s accompanying condensed consolidated financial statements. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions. These estimates and assumptions affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of revenues and expenses during the reporting periods. For example, significant estimates and assumptions have been made with respect to useful lives of assets, capitalization of development costs, fair value measurements, provision for impairment, including estimates of holding periods, capitalization rates and discount rates (where applicable), provision for income taxes, recoverable amounts of receivables, deferred taxes and initial valuations and related amortization periods of deferred costs and intangibles, particularly with respect to property acquisitions. Actual results could differ from these estimates. All share amounts and dollar amounts in the condensed consolidated financial statements and notes thereto are stated in thousands with the exception of per share amounts and per square foot amounts. The accompanying condensed consolidated financial statements include the accounts of the Company, as well as all wholly-owned subsidiaries and any consolidated variable interest entities (VIEs). All intercompany balances and transactions have been eliminated in consolidation. Wholly-owned subsidiaries generally consist of limited liability companies (LLCs), limited partnerships and statutory trusts. The Company’s property ownership as of September 30, 2016 is summarized below: Wholly-owned Retail operating properties (a) 174 Office properties 1 Total operating properties 175 Development and redevelopment properties 2 (a) Excludes one wholly-owned operating property classified as held for sale as of September 30, 2016 .

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Refer to the Company’s 2015 Annual Report on Form 10-K for a summary of its significant accounting policies. Except as disclosed below, there have been no changes to the Company’s significant accounting policies in the nine months ended September 30, 2016 . Recently Adopted Accounting Pronouncements Effective January 1, 2016, the Company adopted Accounting Standards Update (ASU) 2015-02, Consolidation , which revised the consolidation guidance for all entities. The new standard modifies the evaluation of whether limited partnerships and similar legal entities are VIEs or voting interest entities, eliminates the presumption that a general partner should consolidate a limited partnership and affects the consolidation analysis of reporting entities that are involved with VIEs. The adoption of this pronouncement under the modified retrospective method did not have any effect on the Company’s condensed consolidated financial statements as the Company did not have any VIEs as of January 1, 2016; however, during the nine months ended September 30, 2016 , the Company had acquired three properties through consolidated VIEs and, accordingly, applied the revised consolidation guidance. See Note 3 to the condensed consolidated financial statements for further details. Effective January 1, 2016, the Company adopted ASU 2015-16, Business Combinations , which requires the acquirer in a business combination to recognize in the period any adjustments to provisional amounts that are identified during the measurement period rather than retrospectively accounting for those adjustments. The adoption of this pronouncement did not have any effect on the Company’s condensed consolidated financial statements. The Company elected to early adopt ASU 2014-15, Presentation of Financial Statements – Going Concern , on January 1, 2016. The new standard requires a company’s management to assess the entity’s ability to continue as a going concern for a period of one year after the date the financial statements are issued (or available to be issued) and provide certain disclosures if conditions or events raise substantial doubt about the entity’s ability to continue as a going concern. The adoption of this pronouncement did not have any effect on the Company’s condensed consolidated financial statements. The Company elected to early adopt ASU 2016-09, Compensation – Stock Compensation , on January 1, 2016. The new standard allowed the Company to make an accounting policy election to account for share-based payment award forfeitures when they occur, which required a modified retrospective transition by means of a cumulative-effect adjustment to equity as of the beginning of the period of adoption and resulted in an adjustment of $17 to additional paid-in capital and accumulated distributions in excess of earnings as of January 1, 2016. Other Recently Issued Accounting Pronouncements In May 2014 with subsequent updates issued in August 2015 and March, April and May 2016, the Financial Accounting Standards Board (FASB) issued ASU 2014-09, Revenue from Contracts with Customers . This new standard is effective January 1, 2018, with early adoption permitted beginning January 1, 2017, and will replace existing revenue recognition standards. The sale of investment property and any non-lease components contained within lease agreements will be required to follow the new standard; however, lease components of lease contracts will be excluded from this standard. This pronouncement allows either a full or a modified retrospective method of adoption. Expanded quantitative and qualitative disclosures regarding revenue recognition will be required for contracts that are subject to this guidance. The Company does not expect the adoption of this pronouncement will have a material effect on its condensed consolidated financial statements; however, it will continue to evaluate this assessment until the guidance becomes effective. In January 2016, the FASB issued ASU 2016-01, Financial Instruments – Overall . This new standard is effective January 1, 2018 and will require companies to disclose the fair value of financial assets and financial liabilities measured at amortized cost in accordance with the exit price notion and will no longer require disclosure of the methods and significant assumptions used, including any changes, to estimate fair value. In addition, companies will be required to disclose all financial assets and financial liabilities grouped by 1) measurement category and 2) form of financial instrument. The Company does not expect the adoption of this pronouncement will have a material effect on its condensed consolidated financial statements; however, it will continue to evaluate this assessment until the guidance becomes effective. In February 2016, the FASB issued ASU 2016-02, Leases . This new standard is effective January 1, 2019, with early adoption permitted, and will require lessees to recognize a liability to make lease payments and a right-of-use asset, initially measured at the present value of lease payments, for both operating and financing leases. For leases with a term of 12 months or less, lessees will be permitted to make an accounting policy election by class of underlying asset to not recognize lease liabilities and lease assets. Under this new pronouncement, lessor accounting will be largely unchanged from existing GAAP. The pronouncement requires a modified retrospective method of adoption, with some optional practical expedients. Upon adoption, the Company will recognize a lease liability and a right-of-use asset for operating leases where it is the lessee, such as ground leases and office and equipment leases. The Company will continue to evaluate the impact of this guidance until it becomes effective. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses . This new standard is effective January 1, 2020, with early adoption permitted beginning January 1, 2019, and replaces the current incurred loss impairment methodology with a methodology that reflects expected credit losses. Financial assets that are measured at amortized cost will be required to be presented at the net amount expected to be collected with an allowance for credit losses deducted from the amortized cost basis. In addition, an entity must consider broader information in developing its expected credit loss estimate, including the use of forecasted information. Generally, the pronouncement requires a modified retrospective method of adoption. The Company will continue to evaluate the impact of this guidance until it becomes effective. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows . This new standard is effective January 1, 2018, with early adoption permitted, and adds or clarifies guidance on the classification of certain cash receipts and payments in the statement of cash flows. Of the eight types of cash flows discussed in the new standard, the classification of debt prepayment and debt extinguishment costs as financing outflows will impact the Company as these items are currently reflected as operating outflows. The pronouncement requires a retrospective transition method of adoption. The Company will continue to evaluate the impact of this guidance until it becomes effective.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Acquisitions	ACQUISITIONS The Company closed on the following acquisitions during the nine months ended September 30, 2016: Date Property Name Metropolitan Property Type Square Footage Acquisition Price January 15, 2016 Shoppes at Hagerstown (a) Hagerstown Multi-tenant retail 113,000 $ 27,055 January 15, 2016 Merrifield Town Center II (a) Washington, D.C. Multi-tenant retail 76,000 45,676 March 29, 2016 Oak Brook Promenade Chicago Multi-tenant retail 183,200 65,954 April 1, 2016 The Shoppes at Union Hill (b) New York Multi-tenant retail 91,700 63,060 April 29, 2016 Ashland & Roosevelt – Fee Interest (c) Chicago Ground lease interest — 13,850 May 5, 2016 Tacoma South Seattle Multi-tenant retail 230,700 39,400 June 15, 2016 Eastside Dallas Multi-tenant retail 67,100 23,842 August 30, 2016 Woodinville Plaza – Anchor Space Improvements (d) Seattle Anchor space improvements (d) — 4,500 761,700 $ 283,337 (a) These properties were acquired as a two -property portfolio. Merrifield Town Center II also contains 62,000 square feet of storage space for a total of 138,000 square feet. (b) In conjunction with the acquisition, the Company assumed mortgage debt with a principal balance of $15,971 and an interest rate of 3.75% that matures in 2031. (c) The Company acquired the fee interest in an existing wholly-owned multi-tenant retail operating property located in Chicago, Illinois, which was previously subject to a ground lease with a third party. In conjunction with this transaction, the Company reversed the straight-line ground rent liability of $6,978 , which is reflected as “Gain on extinguishment of other liabilities” in the accompanying condensed consolidated statements of operations and other comprehensive income. (d) The Company acquired the anchor space improvements, which were previously subject to a ground lease with the Company, in an existing wholly-owned multi-tenant retail operating property located in Woodinville, Washington. The Company closed on the following acquisitions during the nine months ended September 30, 2015: Date Property Name MSA Property Type Square Footage Acquisition Price January 8, 2015 Downtown Crown Washington, D.C. Multi-tenant retail 258,000 $ 162,785 January 23, 2015 Merrifield Town Center Washington, D.C. Multi-tenant retail 84,900 56,500 January 23, 2015 Fort Evans Plaza II Washington, D.C. Multi-tenant retail 228,900 65,000 February 19, 2015 Cedar Park Town Center Austin Multi-tenant retail 179,300 39,057 March 24, 2015 Lake Worth Towne Crossing – Parcel (a) Dallas Land — 400 May 4, 2015 Tysons Corner Washington, D.C. Multi-tenant retail 37,700 31,556 June 10, 2015 Woodinville Plaza Seattle Multi-tenant retail 170,800 35,250 July 31, 2015 Southlake Town Square – Outparcel (b) Dallas Single-user outparcel 13,800 8,440 August 27, 2015 Coal Creek Marketplace Seattle Multi-tenant retail 55,900 17,600 1,029,300 $ 416,588 (a) The Company acquired a parcel located at its Lake Worth Towne Crossing multi-tenant retail operating property. (b) The Company acquired a single-user outparcel located at its Southlake Town Square multi-tenant retail operating property that was subject to a ground lease with the Company prior to the transaction. The following table summarizes the acquisition date fair values, before prorations, the Company recorded in conjunction with the acquisitions discussed above: Nine Months Ended September 30, 2016 2015 Land $ 84,720 $ 146,107 Building and other improvements 176,937 254,377 Acquired lease intangible assets (a) 25,016 39,986 Acquired lease intangible liabilities (b) (3,991 ) (23,882 ) Mortgages payable, net (15,316 ) — Net assets acquired $ 267,366 $ 416,588 (a) The weighted average amortization period for acquired lease intangible assets is 6 years and 15 years for acquisitions completed during the nine months ended September 30, 2016 and 2015 , respectively. (b) The weighted average amortization period for acquired lease intangible liabilities is 11 years and 21 years for acquisitions completed during the nine months ended September 30, 2016 and 2015 , respectively. The above acquisitions were funded using a combination of available cash on hand, proceeds from dispositions and proceeds from the Company’s unsecured revolving line of credit. Transaction costs totaling $913 and $1,297 for the nine months ended September 30, 2016 and 2015 , respectively, were expensed as incurred and are included in “General and administrative expenses” in the accompanying condensed consolidated statements of operations and other comprehensive income. Included in the Company’s condensed consolidated statements of operations and other comprehensive income from the properties acquired that were accounted for as business combinations are $36,210 and $41,169 in total revenues and $7,760 and $7,575 in net income attributable to common shareholders from the date of acquisition through September 30, 2016 and 2015 , respectively. These amounts do not include the total revenue and net income attributable to common shareholders from the 2016 acquisitions of the anchor space improvements in Woodinville Plaza and the fee interest in Ashland & Roosevelt and the 2015 acquisition of a parcel at Lake Worth Towne Crossing as they have been accounted for as asset acquisitions. Condensed Pro Forma Financial Information The results of operations for the acquisitions accounted for as business combinations that were completed during the period, or after such period through the financial statement issuance date, for which financial information was available, are included in the following unaudited condensed pro forma financial information as if these acquisitions had been completed as of the beginning of the year prior to the acquisition date. The following unaudited condensed pro forma financial information is presented as if the 2016 acquisitions were completed as of January 1, 2015 and as if the 2015 acquisitions completed through the date the September 30, 2015 financial statements were issued, were completed as of January 1, 2014. The results of operations associated with the 2016 acquisitions of the anchor space improvements in Woodinville Plaza and the fee interest in Ashland & Roosevelt and the 2015 acquisition of a parcel at Lake Worth Towne Crossing have not been adjusted in the pro forma presentation as they have been accounted for as asset acquisitions. The results of operations associated with the 2015 acquisitions of the outparcels at Southlake Town Square on July 31, 2015 and Royal Oaks Village II on October 27, 2015 have not been adjusted in the pro forma presentation due to a lack of historical financial information. These pro forma results are for comparative purposes only and are not necessarily indicative of what the Company’s actual results of operations would have been had the acquisitions occurred at the beginning of the periods presented, nor are they necessarily indicative of future operating results. The unaudited condensed pro forma financial information is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Total revenues $ 144,526 $ 156,158 $ 444,622 $ 473,387 Net income $ 72,494 $ 77,232 $ 147,421 $ 118,753 Net income attributable to common shareholders $ 70,132 $ 74,870 $ 140,334 $ 111,666 Earnings per common share – basic and diluted Net income per common share attributable to common shareholders $ 0.30 $ 0.32 $ 0.59 $ 0.47 Weighted average number of common shares outstanding – basic 236,783 236,439 236,692 236,348 Variable Interest Entities During the nine months ended September 30, 2016 , the Company entered into agreements with a qualified intermediary related to Internal Revenue Code Section 1031 tax-deferred exchanges (1031 Exchanges). The Company loaned $65,419 , $39,215 and $23,522 to the VIEs to acquire Oak Brook Promenade, Tacoma South and Eastside, respectively. Each 1031 Exchange was completed during the three months ended September 30, 2016 and, in accordance with applicable provisions of the Code, within 180 days after the acquisition date of the property that is the subject of such 1031 Exchange. At the completion of the 1031 Exchanges, the sole membership interests of the VIEs were assigned to the Company and the respective outstanding loans were extinguished, resulting in the entities being wholly owned by the Company and no longer considered VIEs. Prior to the completion of the 1031 Exchanges, the Company was deemed to be the primary beneficiary of the VIEs as it had the ability to direct the activities of the VIEs that most significantly impacted their economic performance and had all of the risks and rewards of ownership. Accordingly, the Company consolidated the VIEs. No value or income was attributed to the noncontrolling interests. The assets of the VIEs consisted of the investment properties which were operated by the Company.

Dispositions

Dispositions	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Dispositions	DISPOSITIONS The Company closed on the following dispositions during the nine months ended September 30, 2016: Date Property Name Property Type Square Footage Consideration Aggregate Proceeds, Net (a) Gain February 1, 2016 The Gateway (b) Multi-tenant retail 623,200 $ 75,000 $ (795 ) $ 3,868 February 10, 2016 Stateline Station Multi-tenant retail 142,600 17,500 17,210 4,253 March 30, 2016 Six Property Portfolio (c) Single-user retail 230,400 35,413 34,986 13,618 April 20, 2016 CVS Pharmacy – Oklahoma City Single-user retail 10,900 4,676 4,608 1,764 June 2, 2016 Rite Aid Store (Eckerd) – Canandaigua & Tim Horton Donut Shop (d) Single-user retail 16,600 5,400 5,333 1,444 June 15, 2016 Academy Sports – Midland (e) Single-user retail 61,200 5,541 5,399 2,220 June 23, 2016 Four Rite Aid Portfolio (f) Single-user retail 45,400 15,934 14,646 2,287 July 8, 2016 Broadway Shopping Center Multi-tenant retail 190,300 20,500 20,103 7,958 July 21, 2016 Mid-Hudson Center Multi-tenant retail 235,600 27,500 25,615 — July 27, 2016 Rite Aid Store (Eckerd), Main St. – Buffalo Single-user retail 10,900 3,388 3,296 344 July 29, 2016 Rite Aid Store (Eckerd) – Lancaster Single-user retail 10,900 3,425 3,349 625 August 4, 2016 Alison’s Corner Multi-tenant retail 55,100 7,850 7,559 3,334 August 5, 2016 Rite Aid Store (Eckerd) – Lake Ave. Single-user retail 13,200 5,400 5,334 907 August 12, 2016 Maple Tree Place Multi-tenant retail 489,000 90,000 87,047 15,566 August 12, 2016 CVS Pharmacy – Burleson Single-user retail 10,900 4,190 4,102 1,425 August 18, 2016 Mitchell Ranch Plaza Multi-tenant retail 199,600 55,625 54,305 33,612 August 22, 2016 Rite Aid Store (Eckerd), E. Main St. – Batavia Single-user retail 13,800 5,050 4,924 1,249 September 9, 2016 Rite Aid Store (Eckerd) – Lockport Single-user retail 13,800 4,690 4,415 753 September 9, 2016 Rite Aid Store (Eckerd), Ferry St. – Buffalo Single-user retail 10,900 3,600 3,370 612 2,384,300 $ 390,682 $ 304,806 $ 95,839 (a) Aggregate proceeds are net of transaction costs. (b) The property was disposed of through a lender-directed sale in full satisfaction of the Company’s $94,353 mortgage obligation. Immediately prior to the disposition, the lender reduced the Company’s loan obligation to $75,000 which was assumed by the buyer in connection with the disposition. Along with the loan reduction, the lender received the balance of the restricted escrows that they held and the rights to unpaid accounts receivable and forgave accrued interest, resulting in a net gain on extinguishment of debt of $13,653 . (c) Portfolio consists of the following properties: (i) Academy Sports – Houma, (ii) Academy Sports – Port Arthur, (iii) Academy Sports – San Antonio, (iv) CVS Pharmacy – Moore, (v) CVS Pharmacy – Saginaw and (vi) Rite Aid Store (Eckerd) – Olean. At the closing of the disposition, proceeds of $34,973 were temporarily restricted related to potential 1031 Exchanges. During the three months ended September 30, 2016 , the related 1031 Exchanges closed and the proceeds were released to the Company. (d) The terms of the disposition of Rite Aid Store (Eckerd) – Canandaigua and Tim Horton Donut Shop were negotiated as a single transaction. (e) At the closing of the disposition, proceeds of $5,383 were temporarily restricted related to a potential 1031 Exchange. During the three months ended September 30, 2016 , the related 1031 Exchange closed and the proceeds were released to the Company. (f) Portfolio consists of the following properties: (i) Rite Aid Store (Eckerd) – Cheektowaga, (ii) Rite Aid Store (Eckerd), W. Main St. – Batavia, (iii) Rite Aid Store (Eckerd), Union Rd. and (iv) Rite Aid Store (Eckerd) – Greece. During the nine months ended September 30, 2016 , the Company also disposed of an outparcel for consideration of $2,639 and recorded a gain of $1,898 from the transaction. At the closing of the disposition, proceeds of $2,549 were temporarily restricted related to a potential 1031 Exchange. During the three months ended September 30, 2016 , the related 1031 Exchange closed and the proceeds were released to the Company. The aggregate proceeds, net of closing costs, from the property dispositions and this additional transaction totaled $307,355 with aggregate gains of $97,737 . The Company closed on the following dispositions during the nine months ended September 30, 2015: Date Property Name Property Type Square Footage Consideration Aggregate Proceeds, Net (a) Gain January 20, 2015 Aon Hewitt East Campus Single-user office 343,000 $ 17,233 $ 16,495 $ — February 27, 2015 Promenade at Red Cliff Multi-tenant retail 94,500 19,050 18,848 4,572 April 7, 2015 Hartford Insurance Building Single-user office 97,400 6,015 5,663 860 April 30, 2015 Rasmussen College Single-user office 26,700 4,800 4,449 1,334 May 15, 2015 Mountain View Plaza Multi-tenant retail 162,000 28,500 27,949 10,184 June 4, 2015 Massillon Commons Multi-tenant retail 245,900 12,520 12,145 — June 5, 2015 Citizen's Property Insurance Building Single-user office 59,800 3,650 3,368 440 June 17, 2015 Pine Ridge Plaza Multi-tenant retail 236,500 33,200 31,858 12,938 June 17, 2015 Bison Hollow Multi-tenant retail 134,800 18,800 18,657 4,061 June 17, 2015 The Village at Quail Springs Multi-tenant retail 100,400 11,350 11,267 3,824 July 17, 2015 Greensburg Commons Multi-tenant retail 272,500 18,400 18,283 2,810 July 28, 2015 Arvada Connection and Arvada Marketplace Multi-tenant retail 367,500 54,900 53,159 20,208 July 30, 2015 Traveler's Office Building Single-user office 50,800 4,841 4,643 — August 6, 2015 Shaw's Supermarket Single-user retail 65,700 3,000 2,769 — August 24, 2015 Harvest Towne Center Multi-tenant retail 39,700 7,800 7,381 1,217 August 31, 2015 Trenton Crossing & McAllen Shopping Center (b) Multi-tenant retail 265,900 39,295 38,410 13,760 September 15, 2015 The Shops at Boardwalk Multi-tenant retail 122,400 27,400 26,634 3,146 September 29, 2015 Best on the Boulevard Multi-tenant retail 204,400 42,500 41,542 15,932 September 29, 2015 Montecito Crossing Multi-tenant retail 179,700 52,200 51,415 17,928 3,069,600 $ 405,454 $ 394,935 $ 113,214 (a) Aggregate proceeds are net of transaction costs and exclude $272 of condemnation proceeds, which did not result in any additional gain recognition. (b) The terms of the disposition of Trenton Crossing and McAllen Shopping Center were negotiated as a single transaction. None of the dispositions completed during the nine months ended September 30, 2016 and 2015 qualified for discontinued operations treatment. As of September 30, 2016 , the Company had entered into a contract to sell Walgreens – Northwoods, a 16,300 square foot single-user retail property located in Northwoods, Missouri. This property qualified for held for sale accounting treatment upon meeting all applicable GAAP criteria during the quarter ended September 30, 2016 , at which time depreciation and amortization were ceased. As such, the assets and liabilities associated with this property are separately classified as held for sale in the condensed consolidated balance sheet as of September 30, 2016 . No properties qualified for held for sale accounting treatment as of December 31, 2015. The following table presents the assets and liabilities associated with the investment property classified as held for sale: September 30, Assets Land, building and other improvements $ 5,524 Accumulated depreciation (2,042 ) Net investment properties 3,482 Other assets 99 Assets associated with investment properties held for sale $ 3,581 Liabilities Other liabilities $ 36 Liabilities associated with investment properties held for sale $ 36

Equity Compensation Plans

Equity Compensation Plans	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Equity Compensation Plans	EQUITY COMPENSATION PLANS The Company’s 2014 Long-Term Equity Compensation Plan, subject to certain conditions, authorizes the issuance of incentive and non-qualified stock options, restricted stock and restricted stock units, stock appreciation rights and other similar awards as well as cash-based awards to the Company’s employees, non-employee directors, consultants and advisors in connection with compensation and incentive arrangements that may be established by the Company’s board of directors or executive management. The following table summarizes the Company’s unvested restricted shares as of and for the nine months ended September 30, 2016 : Unvested Restricted Shares Weighted Average Grant Date Fair Value per Restricted Share Balance as of January 1, 2016 788 $ 15.52 Shares granted (a) 269 $ 14.74 Shares vested (460 ) $ 15.48 Shares forfeited (b) (10 ) $ 14.70 Balance as of September 30, 2016 (c) 587 $ 15.21 (a) Shares granted vest over periods ranging from 0.4 years to 3.9 years in accordance with the terms of applicable award agreements. (b) Effective January 1, 2016, the Company made an accounting policy election to account for forfeitures when they occur. (c) As of September 30, 2016 , total unrecognized compensation expense related to unvested restricted shares was $4,120 , which is expected to be amortized over a weighted average term of 1.4 years . In addition, during the nine months ended September 30, 2016 , performance restricted stock units (RSUs) were granted to the Company’s executives. In 2019, following the performance period which concludes on December 31, 2018, one-third of the RSUs will convert into shares of common stock and two-thirds will convert into restricted shares with a one year vesting term. As long as the minimum hurdle is achieved and the executive remains employed during the performance period, the RSUs will convert into shares of common stock and restricted shares at a conversion rate of between 50% and 200% based upon the Company’s Total Shareholder Return as compared to that of the peer companies within the National Association of Real Estate Investment Trusts (NAREIT) Shopping Center Index for 2016 through 2018. If an executive terminates employment during the performance period by reason of a qualified termination, as defined in the agreement, only a prorated portion of his or her outstanding RSUs will be eligible for conversion based upon the period in which the executive was employed during the performance period. If an executive terminates for any reason other than a qualified termination during the performance period, he or she would forfeit his or her outstanding RSUs. In 2019, additional shares of common stock will also be issued in an amount equal to the accumulated value of the dividends that would have been paid during the performance period on the shares of common stock and restricted shares issued at the end of the performance period divided by the then-current market price of the Company’s common stock. The Company calculated the grant date fair value per unit using a Monte Carlo simulation based on the probability of satisfying the market performance hurdles over the remainder of the performance period. Assumptions as of the grant dates included a weighted average risk-free interest rate of 0.89% , the Company’s historical common stock performance relative to the peer companies within the NAREIT Shopping Center Index and the Company’s weighted average common stock dividend yield of 4.59% . The following table summarizes the Company’s unvested RSUs as of and for the nine months ended September 30, 2016 : Unvested RSUs Weighted Average Grant Date Fair Value per RSU RSUs eligible for future conversion as of January 1, 2016 174 $ 14.20 RSUs granted 246 $ 13.85 RSUs ineligible for conversion (29 ) $ 13.56 RSUs eligible for future conversion as of September 30, 2016 (a) 391 $ 14.02 (a) As of September 30, 2016 , total unrecognized compensation expense related to unvested RSUs was $3,861 , which is expected to be amortized over a weighted average term of 2.7 years . During the three months ended September 30, 2016 and 2015 , the Company recorded compensation expense of $1,594 and $2,099 , respectively, related to unvested restricted shares and RSUs. During the nine months ended September 30, 2016 and 2015 , the Company recorded compensation expense of $5,296 and $8,225 , respectively, related to unvested restricted shares and RSUs. Included within the compensation expense recorded during the nine months ended September 30, 2015 is compensation expense of $1,680 related to the accelerated vesting of 134 restricted shares in conjunction with the departure of the Company’s former Chief Financial Officer and Treasurer. The total fair value of restricted shares vested during the nine months ended September 30, 2016 was $6,830 . Prior to 2013, non-employee directors had been granted options to acquire shares under the Company’s Third Amended and Restated Independent Director Stock Option and Incentive Plan. During the three months ended September 30, 2016 , options to purchase two shares were exercised and options to purchase 10 shares were forfeited. As of September 30, 2016 , options to purchase 41 shares of common stock remained outstanding and exercisable. The Company did not grant any options in 2016 or 2015 and did not record any compensation expense related to stock options during the nine months ended September 30, 2016 and 2015 .

Mortgages Payable

Mortgages Payable	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Mortgages Payable	MORTGAGES PAYABLE The following table summarizes the Company’s mortgages payable: September 30, 2016 December 31, 2015 Aggregate Principal Balance Weighted Average Interest Rate Weighted Average Years to Maturity Aggregate Principal Balance Weighted Average Interest Rate Weighted Average Years to Maturity Fixed rate mortgages payable (a) $ 1,004,879 6.06 % 3.7 $ 1,128,505 (b) 6.08 % 3.9 Premium, net of accumulated amortization 1,544 1,865 Discount, net of accumulated amortization (633 ) (1 ) Capitalized loan fees, net of accumulated amortization (5,701 ) (7,233 ) Mortgages payable, net $ 1,000,089 $ 1,123,136 (a) The fixed rate mortgages had interest rates ranging from 3.50% to 8.00% and 3.35% to 8.00% as of September 30, 2016 and December 31, 2015 , respectively. (b) Includes $7,910 of variable rate mortgage debt that was swapped to a fixed rate as of December 31, 2015 . During the nine months ended September 30, 2016 , the Company disposed of The Gateway through a lender-directed sale in full satisfaction of its $94,353 mortgage obligation, which had a fixed interest rate of 6.57% . Immediately prior to the disposition, the lender reduced the Company’s loan obligation to $75,000 which was assumed by the buyer in connection with the disposition. Along with the loan reduction, the lender received the balance of the restricted escrows that they held and the rights to unpaid accounts receivable and forgave accrued interest, resulting in a net gain on extinguishment of debt of $13,653 . In addition, during the nine months ended September 30, 2016 , the Company repaid mortgages payable in the total amount of $35,344 which had a weighted average fixed interest rate of 4.34% and made scheduled principal payments of $9,900 related to amortizing loans. One of the mortgages repaid, with a principal balance of $7,750 at maturity, had been swapped to a fixed rate and the Company had guaranteed a portion of the outstanding balance. Upon repayment of the mortgage on its scheduled maturity date, the interest rate swap expired and the Company’s guarantee was extinguished. The Company also assumed a mortgage payable with a principal balance of $15,971 and an interest rate of 3.75% that matures in 2031 in conjunction with the acquisition of The Shoppes at Union Hill. The majority of the Company’s mortgages payable require monthly payments of principal and interest, as well as reserves for real estate taxes and certain other costs. The Company’s properties and the related tenant leases are pledged as collateral for its mortgages payable. At times, the Company has borrowed funds financed as part of a cross-collateralized package, with cross-default provisions. In those circumstances, one or more of the Company’s properties may secure the debt of another of the Company’s properties. As of September 30, 2016 , the Company had a pool of mortgages with a principal balance of $391,436 that was cross-collateralized by the 48 properties in its IW JV 2009, LLC portfolio. Debt Maturities The following table shows the scheduled maturities and principal amortization of the Company’s indebtedness as of September 30, 2016 for the remainder of 2016 , each of the next four years and thereafter and the weighted average interest rates by year. The table does not reflect the impact of any debt activity that occurred after September 30, 2016 . 2016 2017 2018 2019 2020 Thereafter Total Debt: Fixed rate debt: Mortgages payable (a) $ 2,865 $ 227,451 $ 11,647 $ 444,324 $ 4,334 $ 314,258 $ 1,004,879 Unsecured credit facility – fixed rate term loan (b) — — — — — 250,000 250,000 Unsecured notes payable (c) — — — — — 600,000 600,000 Total fixed rate debt 2,865 227,451 11,647 444,324 4,334 1,164,258 1,854,879 Variable rate debt: Unsecured credit facility – variable rate term loan — — 200,000 — — — 200,000 Total variable rate debt — — 200,000 — — — 200,000 Total debt (d) $ 2,865 $ 227,451 $ 211,647 $ 444,324 $ 4,334 $ 1,164,258 $ 2,054,879 Weighted average interest rate on debt: Fixed rate debt 7.18 % 5.08 % 6.52 % 7.49 % 4.58 % 3.85 % 4.90 % Variable rate debt (e) — — 1.97 % — — — 1.97 % Total 7.18 % 5.08 % 2.22 % 7.49 % 4.58 % 3.85 % 4.61 % (a) Excludes mortgage premium of $1,544 and discount of $(633) , net of accumulated amortization, as of September 30, 2016 . (b) $250,000 of London Interbank Offered Rate (LIBOR)-based variable rate debt has been swapped to a fixed rate through two interest rate swaps. The swaps effectively convert one-month floating rate LIBOR to a weighted average fixed rate of 0.6677% through December 31, 2017. (c) Excludes discount of $(1,001) , net of accumulated amortization, as of September 30, 2016 and $100,000 of 12-year 4.24% senior unsecured notes which the Company expects to issue on December 28, 2016 pursuant to a note purchase agreement it entered into with certain institutional investors on September 30, 2016. (d) Total debt excludes capitalized loan fees of $(11,919) , net of accumulated amortization, as of September 30, 2016 which are included as a reduction to the respective debt balances. The weighted average years to maturity of consolidated indebtedness was 4.8 years as of September 30, 2016 . (e) Represents interest rates as of September 30, 2016 . The Company plans on addressing its debt maturities through a combination of proceeds from asset dispositions, capital markets transactions and its unsecured revolving line of credit.

Unsecured Notes Payable

Unsecured Notes Payable	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Unsecured Notes Payable	UNSECURED NOTES PAYABLE The following table summarizes the Company’s unsecured notes payable: September 30, 2016 December 31, 2015 Unsecured Notes Payable Maturity Date Principal Balance Interest Rate/ Weighted Average Interest Rate Principal Balance Interest Rate/ Weighted Average Interest Rate Senior notes – 4.12% due 2021 June 30, 2021 $ 100,000 4.12 % $ 100,000 4.12 % Senior notes – 4.58% due 2024 June 30, 2024 150,000 4.58 % 150,000 4.58 % Senior notes – 4.00% due 2025 March 15, 2025 250,000 4.00 % 250,000 4.00 % Senior notes – 4.08% due 2026 (a) September 30, 2026 100,000 (a) 4.08 % — — % 600,000 4.18 % 500,000 4.20 % Discount, net of accumulated amortization (1,001 ) (1,090 ) Capitalized loan fees, net of accumulated amortization (3,520 ) (3,334 ) Total $ 595,479 $ 495,576 (a) On September 30, 2016, the Company issued $100,000 of 10-year 4.08% senior unsecured notes (Notes Due 2026) in a private placement transaction pursuant to a note purchase agreement it entered into with certain institutional investors on September 30, 2016. The proceeds were used to pay down the Company’s unsecured revolving line of credit and for general corporate purposes. Pursuant to the same note purchase agreement, the Company also expects to issue $100,000 of 12-year 4.24% senior unsecured notes on December 28, 2016. The indenture, as supplemented, governing the 4.00% senior unsecured notes due 2025 ( 4.00% Notes Due 2025) (the Indenture) contains customary covenants and events of default. Pursuant to the terms of the Indenture, the Company is subject to various financial covenants, including the requirement to maintain the following: (i) maximum secured and total leverage ratios; (ii) a debt service coverage ratio; and (iii) maintenance of an unencumbered assets to unsecured debt ratio. The note purchase agreement governing the 4.12% senior unsecured notes due 2021 and the 4.58% senior unsecured notes due 2024 (collectively, Notes Due 2021 and 2024) contains customary representations, warranties and covenants, and events of default. Pursuant to the terms of the note purchase agreement, the Company is subject to various financial covenants, some of which are based upon the financial covenants in effect in the Company’s primary credit facility, including the requirement to maintain the following: (i) maximum unencumbered, secured and consolidated leverage ratios; (ii) minimum interest coverage and unencumbered interest coverage ratios; and (iii) a minimum consolidated net worth. The note purchase agreement governing the 4.08% senior unsecured notes due 2026 and that will govern the 4.24% senior unsecured notes due 2028 (collectively, Notes Due 2026 and 2028) contains customary representations, warranties and covenants, and events of default. Pursuant to the terms of the note purchase agreement, the Company is subject to various financial covenants, including the requirement to maintain the following: (i) maximum unencumbered, secured and consolidated leverage ratios; (ii) a minimum interest coverage ratio; (iii) a fixed charge coverage ratio (as set forth in the Company’s unsecured credit facility); and (iv) an unencumbered interest coverage ratio (as set forth in the Company’s unsecured credit facility and the note purchase agreement governing the Notes Due 2021 and 2024). As of September 30, 2016 , management believes the Company was in compliance with the financial covenants under the Indenture and the note purchase agreements.

Unsecured Credit Facility

Unsecured Credit Facility	9 Months Ended
	Sep. 30, 2016
Line of Credit Facility [Abstract]
Unsecured Credit Facility	UNSECURED CREDIT FACILITY On January 6, 2016, the Company entered into its fourth amended and restated unsecured credit agreement with a syndicate of financial institutions led by KeyBank National Association serving as administrative agent and Wells Fargo Bank, National Association serving as syndication agent to provide for an unsecured credit facility aggregating $1,200,000 . The Company’s unsecured credit facility consists of a $750,000 unsecured revolving line of credit, a $250,000 unsecured term loan and a $200,000 unsecured term loan (collectively, the Company’s Unsecured Credit Facility) and is priced on a leverage grid at a rate of LIBOR plus a credit spread. The Company received investment grade credit ratings from two rating agencies in 2014. In accordance with the unsecured credit agreement, the Company may elect to convert to an investment grade pricing grid. As of September 30, 2016 , making such an election would have resulted in a higher interest rate and, as such, the Company has not made the election to convert to an investment grade pricing grid. The following table summarizes the key terms of the Company’s Unsecured Credit Facility: Leverage-Based Pricing Ratings-Based Pricing Unsecured Credit Facility Maturity Date Extension Option Extension Fee Credit Spread Unused Fee Credit Spread Facility Fee $250,000 unsecured term loan 1/5/2021 N/A N/A 1.30% - 2.20% N/A 0.90% - 1.75% N/A $200,000 unsecured term loan 5/11/2018 2 one year 0.15% 1.45% - 2.20% N/A 1.05% - 2.05% N/A $750,000 unsecured revolving line of credit 1/5/2020 2 six month 0.075% 1.35% - 2.25% 0.15% - 0.25% 0.85% - 1.55% 0.125% - 0.30% The Company’s Unsecured Credit Facility has a $400,000 accordion option that allows the Company, at its election, to increase the total credit facility up to $1,600,000 , subject to (i) customary fees and conditions including, but not limited to, the absence of an event of default as defined in the agreement and (ii) the Company’s ability to obtain additional lender commitments. The following table summarizes the Company’s Unsecured Credit Facility: September 30, 2016 December 31, 2015 Unsecured Credit Facility Balance Interest Rate/ Weighted Average Interest Rate Balance Interest Rate/ $250,000 unsecured term loan – fixed rate (a) $ 250,000 1.97 % $ — — % $200,000 unsecured term loan – variable rate 200,000 1.97 % — — % $450,000 unsecured term loan – fixed rate portion (b) — — % 300,000 1.99 % $450,000 unsecured term loan – variable rate portion — — % 150,000 1.88 % Subtotal 450,000 450,000 Capitalized loan fees, net of accumulated amortization (2,698 ) (2,474 ) Term loans, net 447,302 447,526 Revolving line of credit – variable rate (c) — 1.87 % 100,000 1.93 % Total unsecured credit facility, net $ 447,302 1.97 % $ 547,526 1.95 % (a) As of September 30, 2016 , $250,000 of LIBOR-based variable rate debt has been swapped to a weighted average fixed rate of 0.6677% plus a credit spread based on a leverage grid ranging from 1.30% to 2.20% through December 31, 2017. The applicable credit spread was 1.30% as of September 30, 2016 . (b) As of December 31, 2015, $300,000 of LIBOR-based variable rate debt had been swapped to a fixed rate of 0.53875% plus a credit spread based on a leverage grid ranging from 1.45% to 2.00% through February 2016. The applicable credit spread was 1.45% as of December 31, 2015. (c) Excludes capitalized loan fees, which are included in “Other assets, net” in the accompanying condensed consolidated balance sheets. The fourth amended and restated unsecured credit agreement contains customary representations, warranties and covenants, and events of default. Pursuant to the terms of the fourth amended and restated unsecured credit agreement, the Company is subject to various financial covenants, including the requirement to maintain the following: (i) maximum unencumbered, secured and consolidated leverage ratios; and (ii) minimum fixed charge and unencumbered interest coverage ratios. As of September 30, 2016 , management believes the Company was in compliance with the financial covenants and default provisions under the unsecured credit agreement. The Company previously had a $1,000,000 unsecured credit facility that consisted of a $550,000 unsecured revolving line of credit and a $450,000 unsecured term loan that bore interest at a rate of LIBOR plus a credit spread ranging from 1.45% to 2.05% and was scheduled to mature on May 12, 2017 for the unsecured revolving line of credit and May 11, 2018 for the unsecured term loan.

Derivatives

Derivatives	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	DERIVATIVES The Company’s objective in using interest rate derivatives is to manage its exposure to interest rate movements and add stability to interest expense. To accomplish this objective, the Company uses interest rate swaps as part of its interest rate risk management strategy. Interest rate swaps designated as cash flow hedges involve the receipt of variable rate amounts from a counterparty in exchange for the Company making fixed rate payments over the life of the agreement without exchange of the underlying notional amount. The Company utilizes two interest rate swaps to hedge the variable cash flows associated with variable rate debt. The effective portion of changes in the fair value of derivatives that are designated and that qualify as cash flow hedges is recorded in “Accumulated other comprehensive income (loss)” and is reclassified to interest expense as interest payments are made on the Company’s variable rate debt. Over the next 12 months, the Company estimates that an additional $34 will be reclassified as a decrease to interest expense. The ineffective portion of the change in fair value of derivatives is recognized directly in earnings. During the nine months ended September 30, 2016 , the Company entered into the following two interest rate swaps which effectively convert one-month floating rate LIBOR to a fixed rate: Effective Date Notional Fixed Interest Rate Termination Date March 1, 2016 $ 100,000 0.6591 % December 31, 2017 May 16, 2016 $ 150,000 0.6735 % December 31, 2017 The Company previously had a $300,000 interest rate swap that matured on February 24, 2016. In addition, during the nine months ended September 30, 2016 , the Company repaid a $7,750 variable rate mortgage payable that had been swapped to a fixed rate. Upon repayment of the mortgage on its scheduled maturity date, the interest rate swap expired. As of December 31, 2015, the outstanding principal balance of this variable rate mortgage was $7,910 . The following table summarizes the Company’s interest rate swaps that were designated as cash flow hedges of interest rate risk: Number of Instruments Notional Interest Rate Derivatives September 30, December 31, September 30, December 31, Interest rate swaps 2 2 $ 250,000 $ 307,910 The table below presents the estimated fair value of the Company’s derivative financial instruments as well as their classification in the condensed consolidated balance sheets. The valuation techniques utilized are described in Note 13 to the condensed consolidated financial statements. September 30, 2016 December 31, 2015 Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as cash flow hedges: Interest rate swaps Other assets, net $ 138 N/A $ — Interest rate swaps N/A $ — Other liabilities $ 85 The following table presents the effect of the Company’s derivative financial instruments on the accompanying condensed consolidated statements of operations and other comprehensive income: Derivatives in Cash Flow Hedging Relationships Amount of (Gain) Loss Recognized in Other Comprehensive Income on Derivative (Effective Portion) Location of Loss Reclassified from Accumulated Other Comprehensive Income (AOCI) into Income (Effective Portion) Amount of Loss Reclassified from AOCI into Income (Effective Portion) Location of Gain Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Interest rate swaps Three Months Ended September 30, Nine Months Three Months Nine Months Three Months Nine Months 2016 $ (534 ) $ 153 Interest expense $ 132 $ 342 Other income, net $ (38 ) $ (35 ) 2015 $ 109 $ 691 Interest expense $ 264 $ 848 Other income, net $ (4 ) $ (25 )

Equity

Equity	9 Months Ended
	Sep. 30, 2016
Equity [Abstract]
Equity	EQUITY In December 2015, the Company entered into a new at-the-market (ATM) equity program under which it may issue and sell shares of its Class A common stock, having an aggregate offering price of up to $250,000 , from time to time. The 2015 ATM equity program supersedes the Company’s previous $200,000 ATM equity program which was in place from March 2013 through November 2015. Actual sales may depend on a variety of factors, including, among others, market conditions and the trading price of the Company’s Class A common stock. Any net proceeds are expected to be used for general corporate purposes, which may include the funding of acquisitions and redevelopment activities and the repayment of debt, including the Company’s Unsecured Credit Facility. The Company did not sell any shares under its ATM equity programs during the nine months ended September 30, 2016 and 2015 . As of September 30, 2016 , the Company had Class A common shares having an aggregate offering price of up to $250,000 remaining available for sale under its ATM equity program. In December 2015, the Company’s board of directors authorized a common stock repurchase program under which the Company may repurchase, from time to time, up to a maximum of $250,000 of shares of its Class A common stock. The shares may be repurchased in the open market or in privately negotiated transactions. The timing and actual number of shares repurchased will depend on a variety of factors, including price in absolute terms and in relation to the value of the Company’s assets, corporate and regulatory requirements, market conditions and other corporate liquidity requirements and priorities. The common stock repurchase program may be suspended or terminated at any time without prior notice. As of September 30, 2016 , the Company had not repurchased any shares under this program.

Earnings per Share

Earnings per Share	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Earnings per Share	EARNINGS PER SHARE The following table summarizes the components used in the calculation of basic and diluted earnings per share (EPS): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Numerator: Income from continuing operations $ 6,109 $ 3,328 $ 50,785 $ 8,875 Gain on sales of investment properties 66,385 75,001 97,737 113,214 Preferred stock dividends (2,362 ) (2,362 ) (7,087 ) (7,087 ) Net income attributable to common shareholders 70,132 75,967 141,435 115,002 Distributions paid on unvested restricted shares (108 ) (130 ) (348 ) (340 ) Net income attributable to common shareholders excluding amounts attributable to unvested restricted shares $ 70,024 $ 75,837 $ 141,087 $ 114,662 Denominator: Denominator for earnings per common share – basic: Weighted average number of common shares outstanding 236,783 (a) 236,439 (b) 236,692 (a) 236,348 (b) Effect of dilutive securities: Stock options 2 (c) 2 (c) 2 (c) 2 (c) RSUs 323 (d) 112 (e) 289 (d) 50 (e) Denominator for earnings per common share – diluted: Weighted average number of common and common equivalent shares outstanding 237,108 236,553 236,983 236,400 (a) Excludes 587 shares of unvested restricted common stock as of September 30, 2016 , which equate to 596 and 657 shares, respectively, on a weighted average basis for the three and nine months ended September 30, 2016 . These shares will continue to be excluded from the computation of basic EPS until contingencies are resolved and the shares are released. (b) Excludes 848 shares of unvested restricted common stock as of September 30, 2015 , which equate to 818 and 760 shares, respectively, on a weighted average basis for the three and nine months ended September 30, 2015 . These shares were excluded from the computation of basic EPS as the contingencies remained and the shares had not been released as of the end of the reporting period. (c) There were outstanding options to purchase 41 and 53 shares of common stock as of September 30, 2016 and 2015 , respectively, at a weighted average exercise price of $19.33 and $19.39 , respectively. Of these totals, outstanding options to purchase 35 and 45 shares of common stock as of September 30, 2016 and 2015 , respectively, at a weighted average exercise price of $20.63 and $20.74 , respectively, have been excluded from the common shares used in calculating diluted earnings per share as including them would be anti-dilutive. (d) There were 391 RSUs eligible for future conversion following the performance periods as of September 30, 2016 (see Note 5 to the condensed consolidated financial statements), which equate to 391 and 360 RSUs on a weighted average basis for the three and nine months ended September 30, 2016 , respectively. These contingently issuable shares are included in diluted EPS based on the weighted average number of shares that would be outstanding during the period, if any, assuming the end of the reporting period was the end of the contingency periods. (e) There were 180 RSUs eligible for future conversion following the performance period as of September 30, 2015 , which equate to 168 and 76 RSUs on a weighted average basis for the three and nine months ended September 30, 2015 , respectively. These contingently issuable shares are included in diluted EPS based on the weighted average number of shares that would have been outstanding during the period, if any, assuming September 30, 2015 was the end of the contingency period.

Provision for Impairment of Inv

Provision for Impairment of Investment Properties	9 Months Ended
	Sep. 30, 2016
Impairment or Disposal of Tangible Assets Disclosure [Abstract]
Provision for Impairment of Investment Properties	PROVISION FOR IMPAIRMENT OF INVESTMENT PROPERTIES As of September 30, 2016 and 2015 , the Company identified indicators of impairment at certain of its properties. Such indicators included a low occupancy rate, difficulty in leasing space and related cost of re-leasing, financially troubled tenants or reduced anticipated holding periods. The following table summarizes the results of these analyses as of September 30, 2016 and 2015 : September 30, 2016 September 30, 2015 Number of properties for which indicators of impairment were identified 5 3 (a) Less: number of properties for which an impairment charge was recorded 1 — Less: number of properties that were held for sale as of the date the analysis was performed for which indicators of impairment were identified but no impairment charge was recorded 1 — Remaining properties for which indicators of impairment were identified but no impairment charge was considered necessary 3 3 Weighted average percentage by which the projected undiscounted cash flows exceeded its respective carrying value for each of the remaining properties 14 % 39 % (a) Includes two properties which have subsequently been sold as of September 30, 2016 . The Company recorded the following investment property impairment charges during the nine months ended September 30, 2016 : Property Name Property Type Impairment Date Square Footage Provision for Impairment of Investment Properties South Billings Center (a) Development March 31, 2016 — $ 2,164 Mid-Hudson Center (b) Multi-tenant retail June 30, 2016 235,600 4,142 Saucon Valley Square (c) Multi-tenant retail September 30, 2016 80,700 4,742 $ 11,048 Estimated fair value of impaired properties as of impairment date $ 37,100 (a) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract, which was subsequently terminated. The property was not under active development as of September 30, 2016 . (b) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract. This property was classified as held for sale as of June 30, 2016 and was sold on July 21, 2016. (c) The Company recorded an impairment charge driven by a change in the estimated holding period for the property. The Company recorded the following investment property impairment charges during the nine months ended September 30, 2015 : Property Name Property Type Impairment Date Square Footage Provision for Impairment of Investment Properties Massillon Commons (a) Multi-tenant retail June 4, 2015 245,900 $ 2,289 Traveler’s Office Building (b) Single-user office June 30, 2015 50,800 1,655 Shaw’s Supermarket (a) Single-user retail August 6, 2015 65,700 169 $ 4,113 Estimated fair value of impaired properties as of impairment date $ 20,970 (a) The Company recorded impairment charges based upon the terms and conditions of an executed sales contract for the respective properties, which were sold during 2015. (b) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract. This property was classified as held for sale as of June 30, 2015 and was sold on July 30, 2015. The Company can provide no assurance that material impairment charges with respect to its investment properties will not occur in future periods.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	FAIR VALUE MEASUREMENTS The following table presents the carrying value and estimated fair value of the Company’s financial instruments: September 30, 2016 December 31, 2015 Carrying Value Fair Value Carrying Value Fair Value Financial assets: Derivative asset $ 138 $ 138 $ — $ — Financial liabilities: Mortgages payable, net $ 1,000,089 $ 1,094,472 $ 1,123,136 $ 1,213,620 Unsecured notes payable, net $ 595,479 $ 617,473 $ 495,576 $ 486,701 Unsecured term loans, net $ 447,302 $ 450,000 $ 447,526 $ 450,000 Unsecured revolving line of credit $ — $ — $ 100,000 $ 100,000 Derivative liability $ — $ — $ 85 $ 85 The carrying value of the derivative asset is included in “Other assets, net” and the carrying value of the derivative liability is included in “Other liabilities” in the accompanying condensed consolidated balance sheets. Recurring Fair Value Measurements The following table presents the Company’s financial instruments, which are measured at fair value on a recurring basis, by the level in the fair value hierarchy within which those measurements fall. Methods and assumptions used to estimate the fair value of these instruments are described after the table. Fair Value Level 1 Level 2 Level 3 Total September 30, 2016 Derivative asset $ — $ 138 $ — $ 138 December 31, 2015 Derivative liability $ — $ 85 $ — $ 85 Derivatives: The fair value of the derivative asset and derivative liability are determined using a discounted cash flow analysis on the expected future cash flows of each derivative. This analysis utilizes observable market data including forward yield curves and implied volatilities to determine the market’s expectation of the future cash flows of the variable component. The fixed and variable components of the derivative are then discounted using calculated discount factors developed based on the LIBOR swap rate and are aggregated to arrive at a single valuation for the period. The Company also incorporates credit valuation adjustments to appropriately reflect both its own nonperformance risk and the respective counterparty’s nonperformance risk in the fair value measurements. 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 September 30, 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. As a result, the Company has determined that its derivative valuations in their entirety are classified within Level 2 of the fair value hierarchy. In adjusting the fair value of its derivative contracts for the effect of nonperformance risk, the Company has considered any applicable credit enhancements. The Company’s derivative instruments are further described in Note 9 to the condensed consolidated financial statements. Nonrecurring Fair Value Measurements The following table presents the Company’s assets measured at fair value on a nonrecurring basis as of September 30, 2016 aggregated by the level within the fair value hierarchy in which those measurements fall. The table includes information related to properties remeasured to fair value during the nine months ended September 30, 2016 , except for those properties sold prior to September 30, 2016 . Methods and assumptions used to estimate the fair value of these assets are described after the table. Fair Value Level 1 Level 2 Level 3 Total Provision for Impairment (a) September 30, 2016 Investment properties $ — $ 3,000 (b) $ 6,600 (c) $ 9,600 $ 6,906 (a) Excludes impairment charges recorded on investment properties sold prior to September 30, 2016. (b) Represents the fair value of the Company’s South Billings Center development property, which was not under active development during the nine months ended September 30, 2016 . The estimated fair value of South Billings Center was based upon the expected sales price from the executed sales contract, which was subsequently terminated, and determined to be a Level 2 input. (c) Represents the fair value of the Company’s Saucon Valley Square investment property. The estimated fair value of Saucon Valley Square was determined using the income approach. The income approach involves discounting the estimated income stream and reversion (presumed sale) value of a property over an estimated holding period to a present value at a risk-adjusted rate. Discount rates, growth assumptions and terminal capitalization rates utilized in this approach are derived from property-specific information, market transactions and other financial and industry data. The terminal capitalization rate and discount rate are significant inputs to this valuation. The following are the key Level 3 inputs used in estimating the fair value of Saucon Valley Square as of September 30, 2016 , the date the asset was measured at fair value: Saucon Valley Square Rental growth rates Varies (i) Operating expense growth rate 3.10% Discount rate 9.35% Terminal capitalization rate 8.35% (i) Since cash flow models are established at the tenant level, projected rental revenue growth rates fluctuate over the course of the estimated holding period based upon the timing of lease rollover, amount of available space and other property and space-specific factors. The Company did not have any assets measured at fair value on a nonrecurring basis as of December 31, 2015. Fair Value Disclosures The following table presents the Company’s financial liabilities, which are measured at fair value for disclosure purposes, by the level in the fair value hierarchy within which those measurements fall. Methods and assumptions used to estimate the fair value of these instruments are described after the table. Fair Value Level 1 Level 2 Level 3 Total September 30, 2016 Mortgages payable, net $ — $ — $ 1,094,472 $ 1,094,472 Unsecured notes payable, net $ 249,908 $ — $ 367,565 $ 617,473 Unsecured term loans, net $ — $ — $ 450,000 $ 450,000 December 31, 2015 Mortgages payable, net $ — $ — $ 1,213,620 $ 1,213,620 Unsecured notes payable, net $ 239,482 $ — $ 247,219 $ 486,701 Unsecured term loans, net $ — $ — $ 450,000 $ 450,000 Unsecured revolving line of credit $ — $ — $ 100,000 $ 100,000 Mortgages payable, net: The Company estimates the fair value of its mortgages payable by discounting the anticipated future cash flows of each instrument at rates currently offered to the Company by its lenders for similar debt instruments of comparable maturities. The rates used are not directly observable in the marketplace and judgment is used in determining the appropriate rate for each of the Company’s individual mortgages payable based upon the specific terms of the agreement, including the term to maturity, the quality and nature of the underlying property and its leverage ratio. The rates used range from 2.5% to 3.8% and 2.2% to 6.0% as of September 30, 2016 and December 31, 2015 , respectively. Unsecured notes payable, net: The quoted market price as of September 30, 2016 was used to value the Company’s 4.00% Notes Due 2025. The Company estimates the fair value of its Notes Due 2021 and 2024 and Notes Due 2026 by discounting the future cash flows at rates currently offered to the Company by its lenders for similar debt instruments of comparable maturities. The rates used are not directly observable in the marketplace and judgment is used in determining the appropriate rates. The weighted average rates used were 3.61% and 4.64% as of September 30, 2016 and December 31, 2015 , respectively. Unsecured term loans, net: The Company estimates the fair value of its unsecured term loans, net by discounting the anticipated future cash flows related to the credit spreads at rates currently offered to the Company by its lenders for similar instruments of comparable maturities. The rates used are not directly observable in the marketplace and judgment is used in determining the appropriate rates. The weighted average rates used to discount the credit spreads were 1.37% and 1.30% as of September 30, 2016 and December 31, 2015 , respectively. Unsecured revolving line of credit: The Company estimates the fair value of its unsecured revolving line of credit by discounting the anticipated future cash flows related to the credit spreads at rates currently offered to the Company by its lenders for similar facilities of comparable maturity. The rates used are not directly observable in the marketplace and judgment is used in determining the appropriate rates. The rate used to discount the credit spread was 1.35% as of December 31, 2015 . There were no amounts drawn on the unsecured revolving line of credit as of September 30, 2016 . There were no transfers between the levels of the fair value hierarchy during the nine months ended September 30, 2016 .

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES As of September 30, 2016 , the Company had letter(s) of credit outstanding totaling $143 which serve as collateral for certain capital improvements at one of its properties and reduce the available borrowings on its unsecured revolving line of credit. As of September 30, 2016 , the Company had one active redevelopment at Reisterstown Road Plaza located in Baltimore, Maryland. The Company estimates that it will incur net costs of approximately $11,000 to $12,000 related to the redevelopment, of which $610 has been incurred as of September 30, 2016 .

Litigation

Litigation	9 Months Ended
	Sep. 30, 2016
Litigation Disclosure [Abstract]
Legal Matters and Contingencies	LITIGATION The Company is subject, from time to time, to various legal proceedings and claims that arise in the ordinary course of business. While the resolution of such matters cannot be predicted with certainty, management believes, based on currently available information, that the final outcome of such matters will not have a material effect on the Company’s condensed consolidated financial statements.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2016
Subsequent Events [Abstract]
Subsequent Events	SUBSEQUENT EVENTS On October 24, 2016, the Company’s board of directors (Board) increased the number of directors comprising the Board from eight to nine and appointed Robert G. Gifford as a Director of the Company, effective immediately, to serve until the Company’s 2017 annual meeting of stockholders. On October 25, 2016, the Company declared the cash dividend for the fourth quarter of 2016 for its 7.00% Series A cumulative redeemable preferred stock. The dividend of $0.4375 per preferred share will be paid on December 30, 2016 to preferred shareholders of record at the close of business on December 20, 2016. On October 25, 2016, the Company declared the distribution for the fourth quarter of 2016 of $0.165625 per share on its outstanding Class A common stock, which will be paid on January 10, 2017 to Class A common shareholders of record at the close of business on December 22, 2016.

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2016
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recently Adopted Accounting Pronouncements Effective January 1, 2016, the Company adopted Accounting Standards Update (ASU) 2015-02, Consolidation , which revised the consolidation guidance for all entities. The new standard modifies the evaluation of whether limited partnerships and similar legal entities are VIEs or voting interest entities, eliminates the presumption that a general partner should consolidate a limited partnership and affects the consolidation analysis of reporting entities that are involved with VIEs. The adoption of this pronouncement under the modified retrospective method did not have any effect on the Company’s condensed consolidated financial statements as the Company did not have any VIEs as of January 1, 2016; however, during the nine months ended September 30, 2016 , the Company had acquired three properties through consolidated VIEs and, accordingly, applied the revised consolidation guidance. See Note 3 to the condensed consolidated financial statements for further details. Effective January 1, 2016, the Company adopted ASU 2015-16, Business Combinations , which requires the acquirer in a business combination to recognize in the period any adjustments to provisional amounts that are identified during the measurement period rather than retrospectively accounting for those adjustments. The adoption of this pronouncement did not have any effect on the Company’s condensed consolidated financial statements. The Company elected to early adopt ASU 2014-15, Presentation of Financial Statements – Going Concern , on January 1, 2016. The new standard requires a company’s management to assess the entity’s ability to continue as a going concern for a period of one year after the date the financial statements are issued (or available to be issued) and provide certain disclosures if conditions or events raise substantial doubt about the entity’s ability to continue as a going concern. The adoption of this pronouncement did not have any effect on the Company’s condensed consolidated financial statements. The Company elected to early adopt ASU 2016-09, Compensation – Stock Compensation , on January 1, 2016. The new standard allowed the Company to make an accounting policy election to account for share-based payment award forfeitures when they occur, which required a modified retrospective transition by means of a cumulative-effect adjustment to equity as of the beginning of the period of adoption and resulted in an adjustment of $17 to additional paid-in capital and accumulated distributions in excess of earnings as of January 1, 2016. Other Recently Issued Accounting Pronouncements In May 2014 with subsequent updates issued in August 2015 and March, April and May 2016, the Financial Accounting Standards Board (FASB) issued ASU 2014-09, Revenue from Contracts with Customers . This new standard is effective January 1, 2018, with early adoption permitted beginning January 1, 2017, and will replace existing revenue recognition standards. The sale of investment property and any non-lease components contained within lease agreements will be required to follow the new standard; however, lease components of lease contracts will be excluded from this standard. This pronouncement allows either a full or a modified retrospective method of adoption. Expanded quantitative and qualitative disclosures regarding revenue recognition will be required for contracts that are subject to this guidance. The Company does not expect the adoption of this pronouncement will have a material effect on its condensed consolidated financial statements; however, it will continue to evaluate this assessment until the guidance becomes effective. In January 2016, the FASB issued ASU 2016-01, Financial Instruments – Overall . This new standard is effective January 1, 2018 and will require companies to disclose the fair value of financial assets and financial liabilities measured at amortized cost in accordance with the exit price notion and will no longer require disclosure of the methods and significant assumptions used, including any changes, to estimate fair value. In addition, companies will be required to disclose all financial assets and financial liabilities grouped by 1) measurement category and 2) form of financial instrument. The Company does not expect the adoption of this pronouncement will have a material effect on its condensed consolidated financial statements; however, it will continue to evaluate this assessment until the guidance becomes effective. In February 2016, the FASB issued ASU 2016-02, Leases . This new standard is effective January 1, 2019, with early adoption permitted, and will require lessees to recognize a liability to make lease payments and a right-of-use asset, initially measured at the present value of lease payments, for both operating and financing leases. For leases with a term of 12 months or less, lessees will be permitted to make an accounting policy election by class of underlying asset to not recognize lease liabilities and lease assets. Under this new pronouncement, lessor accounting will be largely unchanged from existing GAAP. The pronouncement requires a modified retrospective method of adoption, with some optional practical expedients. Upon adoption, the Company will recognize a lease liability and a right-of-use asset for operating leases where it is the lessee, such as ground leases and office and equipment leases. The Company will continue to evaluate the impact of this guidance until it becomes effective. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses . This new standard is effective January 1, 2020, with early adoption permitted beginning January 1, 2019, and replaces the current incurred loss impairment methodology with a methodology that reflects expected credit losses. Financial assets that are measured at amortized cost will be required to be presented at the net amount expected to be collected with an allowance for credit losses deducted from the amortized cost basis. In addition, an entity must consider broader information in developing its expected credit loss estimate, including the use of forecasted information. Generally, the pronouncement requires a modified retrospective method of adoption. The Company will continue to evaluate the impact of this guidance until it becomes effective. In August 2016, the FASB issued ASU 2016-15, Statement of Cash Flows . This new standard is effective January 1, 2018, with early adoption permitted, and adds or clarifies guidance on the classification of certain cash receipts and payments in the statement of cash flows. Of the eight types of cash flows discussed in the new standard, the classification of debt prepayment and debt extinguishment costs as financing outflows will impact the Company as these items are currently reflected as operating outflows. The pronouncement requires a retrospective transition method of adoption. The Company will continue to evaluate the impact of this guidance until it becomes effective.

Organization and Basis of Pre25

Organization and Basis of Presentation (Tables)	9 Months Ended
	Sep. 30, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of property ownership	The Company’s property ownership as of September 30, 2016 is summarized below: Wholly-owned Retail operating properties (a) 174 Office properties 1 Total operating properties 175 Development and redevelopment properties 2 (a) Excludes one wholly-owned operating property classified as held for sale as of September 30, 2016 .

Acquisitions (Tables)

Acquisitions (Tables)	9 Months Ended
	Sep. 30, 2016
Business Combinations [Abstract]
Schedule of acquisitions	The Company closed on the following acquisitions during the nine months ended September 30, 2016: Date Property Name Metropolitan Property Type Square Footage Acquisition Price January 15, 2016 Shoppes at Hagerstown (a) Hagerstown Multi-tenant retail 113,000 $ 27,055 January 15, 2016 Merrifield Town Center II (a) Washington, D.C. Multi-tenant retail 76,000 45,676 March 29, 2016 Oak Brook Promenade Chicago Multi-tenant retail 183,200 65,954 April 1, 2016 The Shoppes at Union Hill (b) New York Multi-tenant retail 91,700 63,060 April 29, 2016 Ashland & Roosevelt – Fee Interest (c) Chicago Ground lease interest — 13,850 May 5, 2016 Tacoma South Seattle Multi-tenant retail 230,700 39,400 June 15, 2016 Eastside Dallas Multi-tenant retail 67,100 23,842 August 30, 2016 Woodinville Plaza – Anchor Space Improvements (d) Seattle Anchor space improvements (d) — 4,500 761,700 $ 283,337 (a) These properties were acquired as a two -property portfolio. Merrifield Town Center II also contains 62,000 square feet of storage space for a total of 138,000 square feet. (b) In conjunction with the acquisition, the Company assumed mortgage debt with a principal balance of $15,971 and an interest rate of 3.75% that matures in 2031. (c) The Company acquired the fee interest in an existing wholly-owned multi-tenant retail operating property located in Chicago, Illinois, which was previously subject to a ground lease with a third party. In conjunction with this transaction, the Company reversed the straight-line ground rent liability of $6,978 , which is reflected as “Gain on extinguishment of other liabilities” in the accompanying condensed consolidated statements of operations and other comprehensive income. (d) The Company acquired the anchor space improvements, which were previously subject to a ground lease with the Company, in an existing wholly-owned multi-tenant retail operating property located in Woodinville, Washington. The Company closed on the following acquisitions during the nine months ended September 30, 2015: Date Property Name MSA Property Type Square Footage Acquisition Price January 8, 2015 Downtown Crown Washington, D.C. Multi-tenant retail 258,000 $ 162,785 January 23, 2015 Merrifield Town Center Washington, D.C. Multi-tenant retail 84,900 56,500 January 23, 2015 Fort Evans Plaza II Washington, D.C. Multi-tenant retail 228,900 65,000 February 19, 2015 Cedar Park Town Center Austin Multi-tenant retail 179,300 39,057 March 24, 2015 Lake Worth Towne Crossing – Parcel (a) Dallas Land — 400 May 4, 2015 Tysons Corner Washington, D.C. Multi-tenant retail 37,700 31,556 June 10, 2015 Woodinville Plaza Seattle Multi-tenant retail 170,800 35,250 July 31, 2015 Southlake Town Square – Outparcel (b) Dallas Single-user outparcel 13,800 8,440 August 27, 2015 Coal Creek Marketplace Seattle Multi-tenant retail 55,900 17,600 1,029,300 $ 416,588 (a) The Company acquired a parcel located at its Lake Worth Towne Crossing multi-tenant retail operating property. (b) The Company acquired a single-user outparcel located at its Southlake Town Square multi-tenant retail operating property that was subject to a ground lease with the Company prior to the transaction.
Schedule of acquisition date fair values	The following table summarizes the acquisition date fair values, before prorations, the Company recorded in conjunction with the acquisitions discussed above: Nine Months Ended September 30, 2016 2015 Land $ 84,720 $ 146,107 Building and other improvements 176,937 254,377 Acquired lease intangible assets (a) 25,016 39,986 Acquired lease intangible liabilities (b) (3,991 ) (23,882 ) Mortgages payable, net (15,316 ) — Net assets acquired $ 267,366 $ 416,588 (a) The weighted average amortization period for acquired lease intangible assets is 6 years and 15 years for acquisitions completed during the nine months ended September 30, 2016 and 2015 , respectively. (b) The weighted average amortization period for acquired lease intangible liabilities is 11 years and 21 years for acquisitions completed during the nine months ended September 30, 2016 and 2015 , respectively.
Schedule of condensed pro forma financial information	The unaudited condensed pro forma financial information is as follows: Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Total revenues $ 144,526 $ 156,158 $ 444,622 $ 473,387 Net income $ 72,494 $ 77,232 $ 147,421 $ 118,753 Net income attributable to common shareholders $ 70,132 $ 74,870 $ 140,334 $ 111,666 Earnings per common share – basic and diluted Net income per common share attributable to common shareholders $ 0.30 $ 0.32 $ 0.59 $ 0.47 Weighted average number of common shares outstanding – basic 236,783 236,439 236,692 236,348

Dispositions (Tables)

Dispositions (Tables)	9 Months Ended
	Sep. 30, 2016
Discontinued Operations and Disposal Groups [Abstract]
Schedule of property dispositions	The Company closed on the following dispositions during the nine months ended September 30, 2016: Date Property Name Property Type Square Footage Consideration Aggregate Proceeds, Net (a) Gain February 1, 2016 The Gateway (b) Multi-tenant retail 623,200 $ 75,000 $ (795 ) $ 3,868 February 10, 2016 Stateline Station Multi-tenant retail 142,600 17,500 17,210 4,253 March 30, 2016 Six Property Portfolio (c) Single-user retail 230,400 35,413 34,986 13,618 April 20, 2016 CVS Pharmacy – Oklahoma City Single-user retail 10,900 4,676 4,608 1,764 June 2, 2016 Rite Aid Store (Eckerd) – Canandaigua & Tim Horton Donut Shop (d) Single-user retail 16,600 5,400 5,333 1,444 June 15, 2016 Academy Sports – Midland (e) Single-user retail 61,200 5,541 5,399 2,220 June 23, 2016 Four Rite Aid Portfolio (f) Single-user retail 45,400 15,934 14,646 2,287 July 8, 2016 Broadway Shopping Center Multi-tenant retail 190,300 20,500 20,103 7,958 July 21, 2016 Mid-Hudson Center Multi-tenant retail 235,600 27,500 25,615 — July 27, 2016 Rite Aid Store (Eckerd), Main St. – Buffalo Single-user retail 10,900 3,388 3,296 344 July 29, 2016 Rite Aid Store (Eckerd) – Lancaster Single-user retail 10,900 3,425 3,349 625 August 4, 2016 Alison’s Corner Multi-tenant retail 55,100 7,850 7,559 3,334 August 5, 2016 Rite Aid Store (Eckerd) – Lake Ave. Single-user retail 13,200 5,400 5,334 907 August 12, 2016 Maple Tree Place Multi-tenant retail 489,000 90,000 87,047 15,566 August 12, 2016 CVS Pharmacy – Burleson Single-user retail 10,900 4,190 4,102 1,425 August 18, 2016 Mitchell Ranch Plaza Multi-tenant retail 199,600 55,625 54,305 33,612 August 22, 2016 Rite Aid Store (Eckerd), E. Main St. – Batavia Single-user retail 13,800 5,050 4,924 1,249 September 9, 2016 Rite Aid Store (Eckerd) – Lockport Single-user retail 13,800 4,690 4,415 753 September 9, 2016 Rite Aid Store (Eckerd), Ferry St. – Buffalo Single-user retail 10,900 3,600 3,370 612 2,384,300 $ 390,682 $ 304,806 $ 95,839 (a) Aggregate proceeds are net of transaction costs. (b) The property was disposed of through a lender-directed sale in full satisfaction of the Company’s $94,353 mortgage obligation. Immediately prior to the disposition, the lender reduced the Company’s loan obligation to $75,000 which was assumed by the buyer in connection with the disposition. Along with the loan reduction, the lender received the balance of the restricted escrows that they held and the rights to unpaid accounts receivable and forgave accrued interest, resulting in a net gain on extinguishment of debt of $13,653 . (c) Portfolio consists of the following properties: (i) Academy Sports – Houma, (ii) Academy Sports – Port Arthur, (iii) Academy Sports – San Antonio, (iv) CVS Pharmacy – Moore, (v) CVS Pharmacy – Saginaw and (vi) Rite Aid Store (Eckerd) – Olean. At the closing of the disposition, proceeds of $34,973 were temporarily restricted related to potential 1031 Exchanges. During the three months ended September 30, 2016 , the related 1031 Exchanges closed and the proceeds were released to the Company. (d) The terms of the disposition of Rite Aid Store (Eckerd) – Canandaigua and Tim Horton Donut Shop were negotiated as a single transaction. (e) At the closing of the disposition, proceeds of $5,383 were temporarily restricted related to a potential 1031 Exchange. During the three months ended September 30, 2016 , the related 1031 Exchange closed and the proceeds were released to the Company. (f) Portfolio consists of the following properties: (i) Rite Aid Store (Eckerd) – Cheektowaga, (ii) Rite Aid Store (Eckerd), W. Main St. – Batavia, (iii) Rite Aid Store (Eckerd), Union Rd. and (iv) Rite Aid Store (Eckerd) – Greece. The Company closed on the following dispositions during the nine months ended September 30, 2015: Date Property Name Property Type Square Footage Consideration Aggregate Proceeds, Net (a) Gain January 20, 2015 Aon Hewitt East Campus Single-user office 343,000 $ 17,233 $ 16,495 $ — February 27, 2015 Promenade at Red Cliff Multi-tenant retail 94,500 19,050 18,848 4,572 April 7, 2015 Hartford Insurance Building Single-user office 97,400 6,015 5,663 860 April 30, 2015 Rasmussen College Single-user office 26,700 4,800 4,449 1,334 May 15, 2015 Mountain View Plaza Multi-tenant retail 162,000 28,500 27,949 10,184 June 4, 2015 Massillon Commons Multi-tenant retail 245,900 12,520 12,145 — June 5, 2015 Citizen's Property Insurance Building Single-user office 59,800 3,650 3,368 440 June 17, 2015 Pine Ridge Plaza Multi-tenant retail 236,500 33,200 31,858 12,938 June 17, 2015 Bison Hollow Multi-tenant retail 134,800 18,800 18,657 4,061 June 17, 2015 The Village at Quail Springs Multi-tenant retail 100,400 11,350 11,267 3,824 July 17, 2015 Greensburg Commons Multi-tenant retail 272,500 18,400 18,283 2,810 July 28, 2015 Arvada Connection and Arvada Marketplace Multi-tenant retail 367,500 54,900 53,159 20,208 July 30, 2015 Traveler's Office Building Single-user office 50,800 4,841 4,643 — August 6, 2015 Shaw's Supermarket Single-user retail 65,700 3,000 2,769 — August 24, 2015 Harvest Towne Center Multi-tenant retail 39,700 7,800 7,381 1,217 August 31, 2015 Trenton Crossing & McAllen Shopping Center (b) Multi-tenant retail 265,900 39,295 38,410 13,760 September 15, 2015 The Shops at Boardwalk Multi-tenant retail 122,400 27,400 26,634 3,146 September 29, 2015 Best on the Boulevard Multi-tenant retail 204,400 42,500 41,542 15,932 September 29, 2015 Montecito Crossing Multi-tenant retail 179,700 52,200 51,415 17,928 3,069,600 $ 405,454 $ 394,935 $ 113,214 (a) Aggregate proceeds are net of transaction costs and exclude $272 of condemnation proceeds, which did not result in any additional gain recognition. (b) The terms of the disposition of Trenton Crossing and McAllen Shopping Center were negotiated as a single transaction.
Schedule of assets and liabilities associated with investment properties held for sale	The following table presents the assets and liabilities associated with the investment property classified as held for sale: September 30, Assets Land, building and other improvements $ 5,524 Accumulated depreciation (2,042 ) Net investment properties 3,482 Other assets 99 Assets associated with investment properties held for sale $ 3,581 Liabilities Other liabilities $ 36 Liabilities associated with investment properties held for sale $ 36

Equity Compensation Plans (Tabl

Equity Compensation Plans (Tables)	9 Months Ended
	Sep. 30, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of unvested restricted shares and restricted stock units	The following table summarizes the Company’s unvested RSUs as of and for the nine months ended September 30, 2016 : Unvested RSUs Weighted Average Grant Date Fair Value per RSU RSUs eligible for future conversion as of January 1, 2016 174 $ 14.20 RSUs granted 246 $ 13.85 RSUs ineligible for conversion (29 ) $ 13.56 RSUs eligible for future conversion as of September 30, 2016 (a) 391 $ 14.02 (a) As of September 30, 2016 , total unrecognized compensation expense related to unvested RSUs was $3,861 , which is expected to be amortized over a weighted average term of 2.7 years . The following table summarizes the Company’s unvested restricted shares as of and for the nine months ended September 30, 2016 : Unvested Restricted Shares Weighted Average Grant Date Fair Value per Restricted Share Balance as of January 1, 2016 788 $ 15.52 Shares granted (a) 269 $ 14.74 Shares vested (460 ) $ 15.48 Shares forfeited (b) (10 ) $ 14.70 Balance as of September 30, 2016 (c) 587 $ 15.21 (a) Shares granted vest over periods ranging from 0.4 years to 3.9 years in accordance with the terms of applicable award agreements. (b) Effective January 1, 2016, the Company made an accounting policy election to account for forfeitures when they occur. (c) As of September 30, 2016 , total unrecognized compensation expense related to unvested restricted shares was $4,120 , which is expected to be amortized over a weighted average term of 1.4 years .

Mortgages Payable (Tables)

Mortgages Payable (Tables)	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Summary of mortgages payable	The following table summarizes the Company’s mortgages payable: September 30, 2016 December 31, 2015 Aggregate Principal Balance Weighted Average Interest Rate Weighted Average Years to Maturity Aggregate Principal Balance Weighted Average Interest Rate Weighted Average Years to Maturity Fixed rate mortgages payable (a) $ 1,004,879 6.06 % 3.7 $ 1,128,505 (b) 6.08 % 3.9 Premium, net of accumulated amortization 1,544 1,865 Discount, net of accumulated amortization (633 ) (1 ) Capitalized loan fees, net of accumulated amortization (5,701 ) (7,233 ) Mortgages payable, net $ 1,000,089 $ 1,123,136 (a) The fixed rate mortgages had interest rates ranging from 3.50% to 8.00% and 3.35% to 8.00% as of September 30, 2016 and December 31, 2015 , respectively. (b) Includes $7,910 of variable rate mortgage debt that was swapped to a fixed rate as of December 31, 2015 .
Summary of scheduled maturities and principal amortization of indebtedness	The following table shows the scheduled maturities and principal amortization of the Company’s indebtedness as of September 30, 2016 for the remainder of 2016 , each of the next four years and thereafter and the weighted average interest rates by year. The table does not reflect the impact of any debt activity that occurred after September 30, 2016 . 2016 2017 2018 2019 2020 Thereafter Total Debt: Fixed rate debt: Mortgages payable (a) $ 2,865 $ 227,451 $ 11,647 $ 444,324 $ 4,334 $ 314,258 $ 1,004,879 Unsecured credit facility – fixed rate term loan (b) — — — — — 250,000 250,000 Unsecured notes payable (c) — — — — — 600,000 600,000 Total fixed rate debt 2,865 227,451 11,647 444,324 4,334 1,164,258 1,854,879 Variable rate debt: Unsecured credit facility – variable rate term loan — — 200,000 — — — 200,000 Total variable rate debt — — 200,000 — — — 200,000 Total debt (d) $ 2,865 $ 227,451 $ 211,647 $ 444,324 $ 4,334 $ 1,164,258 $ 2,054,879 Weighted average interest rate on debt: Fixed rate debt 7.18 % 5.08 % 6.52 % 7.49 % 4.58 % 3.85 % 4.90 % Variable rate debt (e) — — 1.97 % — — — 1.97 % Total 7.18 % 5.08 % 2.22 % 7.49 % 4.58 % 3.85 % 4.61 % (a) Excludes mortgage premium of $1,544 and discount of $(633) , net of accumulated amortization, as of September 30, 2016 . (b) $250,000 of London Interbank Offered Rate (LIBOR)-based variable rate debt has been swapped to a fixed rate through two interest rate swaps. The swaps effectively convert one-month floating rate LIBOR to a weighted average fixed rate of 0.6677% through December 31, 2017. (c) Excludes discount of $(1,001) , net of accumulated amortization, as of September 30, 2016 and $100,000 of 12-year 4.24% senior unsecured notes which the Company expects to issue on December 28, 2016 pursuant to a note purchase agreement it entered into with certain institutional investors on September 30, 2016. (d) Total debt excludes capitalized loan fees of $(11,919) , net of accumulated amortization, as of September 30, 2016 which are included as a reduction to the respective debt balances. The weighted average years to maturity of consolidated indebtedness was 4.8 years as of September 30, 2016 . (e) Represents interest rates as of September 30, 2016 .

Unsecured Notes Payable (Tables

Unsecured Notes Payable (Tables)	9 Months Ended
	Sep. 30, 2016
Debt Disclosure [Abstract]
Summary of unsecured notes payable	The following table summarizes the Company’s unsecured notes payable: September 30, 2016 December 31, 2015 Unsecured Notes Payable Maturity Date Principal Balance Interest Rate/ Weighted Average Interest Rate Principal Balance Interest Rate/ Weighted Average Interest Rate Senior notes – 4.12% due 2021 June 30, 2021 $ 100,000 4.12 % $ 100,000 4.12 % Senior notes – 4.58% due 2024 June 30, 2024 150,000 4.58 % 150,000 4.58 % Senior notes – 4.00% due 2025 March 15, 2025 250,000 4.00 % 250,000 4.00 % Senior notes – 4.08% due 2026 (a) September 30, 2026 100,000 (a) 4.08 % — — % 600,000 4.18 % 500,000 4.20 % Discount, net of accumulated amortization (1,001 ) (1,090 ) Capitalized loan fees, net of accumulated amortization (3,520 ) (3,334 ) Total $ 595,479 $ 495,576 (a) On September 30, 2016, the Company issued $100,000 of 10-year 4.08% senior unsecured notes (Notes Due 2026) in a private placement transaction pursuant to a note purchase agreement it entered into with certain institutional investors on September 30, 2016. The proceeds were used to pay down the Company’s unsecured revolving line of credit and for general corporate purposes. Pursuant to the same note purchase agreement, the Company also expects to issue $100,000 of 12-year 4.24% senior unsecured notes on December 28, 2016.

Unsecured Credit Facility (Tabl

Unsecured Credit Facility (Tables)	9 Months Ended
	Sep. 30, 2016
Line of Credit Facility [Abstract]
Summary of unsecured credit facility	The following table summarizes the Company’s Unsecured Credit Facility: September 30, 2016 December 31, 2015 Unsecured Credit Facility Balance Interest Rate/ Weighted Average Interest Rate Balance Interest Rate/ $250,000 unsecured term loan – fixed rate (a) $ 250,000 1.97 % $ — — % $200,000 unsecured term loan – variable rate 200,000 1.97 % — — % $450,000 unsecured term loan – fixed rate portion (b) — — % 300,000 1.99 % $450,000 unsecured term loan – variable rate portion — — % 150,000 1.88 % Subtotal 450,000 450,000 Capitalized loan fees, net of accumulated amortization (2,698 ) (2,474 ) Term loans, net 447,302 447,526 Revolving line of credit – variable rate (c) — 1.87 % 100,000 1.93 % Total unsecured credit facility, net $ 447,302 1.97 % $ 547,526 1.95 % (a) As of September 30, 2016 , $250,000 of LIBOR-based variable rate debt has been swapped to a weighted average fixed rate of 0.6677% plus a credit spread based on a leverage grid ranging from 1.30% to 2.20% through December 31, 2017. The applicable credit spread was 1.30% as of September 30, 2016 . (b) As of December 31, 2015, $300,000 of LIBOR-based variable rate debt had been swapped to a fixed rate of 0.53875% plus a credit spread based on a leverage grid ranging from 1.45% to 2.00% through February 2016. The applicable credit spread was 1.45% as of December 31, 2015. (c) Excludes capitalized loan fees, which are included in “Other assets, net” in the accompanying condensed consolidated balance sheets. The following table summarizes the key terms of the Company’s Unsecured Credit Facility: Leverage-Based Pricing Ratings-Based Pricing Unsecured Credit Facility Maturity Date Extension Option Extension Fee Credit Spread Unused Fee Credit Spread Facility Fee $250,000 unsecured term loan 1/5/2021 N/A N/A 1.30% - 2.20% N/A 0.90% - 1.75% N/A $200,000 unsecured term loan 5/11/2018 2 one year 0.15% 1.45% - 2.20% N/A 1.05% - 2.05% N/A $750,000 unsecured revolving line of credit 1/5/2020 2 six month 0.075% 1.35% - 2.25% 0.15% - 0.25% 0.85% - 1.55% 0.125% - 0.30%

Derivatives (Tables)

Derivatives (Tables)	9 Months Ended
	Sep. 30, 2016
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of derivative instruments	During the nine months ended September 30, 2016 , the Company entered into the following two interest rate swaps which effectively convert one-month floating rate LIBOR to a fixed rate: Effective Date Notional Fixed Interest Rate Termination Date March 1, 2016 $ 100,000 0.6591 % December 31, 2017 May 16, 2016 $ 150,000 0.6735 % December 31, 2017
Schedule of interest rate swaps designated as cash flow hedges	The following table summarizes the Company’s interest rate swaps that were designated as cash flow hedges of interest rate risk: Number of Instruments Notional Interest Rate Derivatives September 30, December 31, September 30, December 31, Interest rate swaps 2 2 $ 250,000 $ 307,910
Schedule of estimated fair value of derivative instruments	The table below presents the estimated fair value of the Company’s derivative financial instruments as well as their classification in the condensed consolidated balance sheets. The valuation techniques utilized are described in Note 13 to the condensed consolidated financial statements. September 30, 2016 December 31, 2015 Balance Sheet Location Fair Value Balance Sheet Location Fair Value Derivatives designated as cash flow hedges: Interest rate swaps Other assets, net $ 138 N/A $ — Interest rate swaps N/A $ — Other liabilities $ 85
Schedule of effect of derivative instruments on the consolidated statements of operations	The following table presents the effect of the Company’s derivative financial instruments on the accompanying condensed consolidated statements of operations and other comprehensive income: Derivatives in Cash Flow Hedging Relationships Amount of (Gain) Loss Recognized in Other Comprehensive Income on Derivative (Effective Portion) Location of Loss Reclassified from Accumulated Other Comprehensive Income (AOCI) into Income (Effective Portion) Amount of Loss Reclassified from AOCI into Income (Effective Portion) Location of Gain Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Amount of Gain Recognized in Income on Derivative (Ineffective Portion and Amount Excluded from Effectiveness Testing) Interest rate swaps Three Months Ended September 30, Nine Months Three Months Nine Months Three Months Nine Months 2016 $ (534 ) $ 153 Interest expense $ 132 $ 342 Other income, net $ (38 ) $ (35 ) 2015 $ 109 $ 691 Interest expense $ 264 $ 848 Other income, net $ (4 ) $ (25 )

Earnings per Share (Tables)

Earnings per Share (Tables)	9 Months Ended
	Sep. 30, 2016
Earnings Per Share [Abstract]
Schedule of components used in the calculation of basic and diluted EPS	The following table summarizes the components used in the calculation of basic and diluted earnings per share (EPS): Three Months Ended September 30, Nine Months Ended September 30, 2016 2015 2016 2015 Numerator: Income from continuing operations $ 6,109 $ 3,328 $ 50,785 $ 8,875 Gain on sales of investment properties 66,385 75,001 97,737 113,214 Preferred stock dividends (2,362 ) (2,362 ) (7,087 ) (7,087 ) Net income attributable to common shareholders 70,132 75,967 141,435 115,002 Distributions paid on unvested restricted shares (108 ) (130 ) (348 ) (340 ) Net income attributable to common shareholders excluding amounts attributable to unvested restricted shares $ 70,024 $ 75,837 $ 141,087 $ 114,662 Denominator: Denominator for earnings per common share – basic: Weighted average number of common shares outstanding 236,783 (a) 236,439 (b) 236,692 (a) 236,348 (b) Effect of dilutive securities: Stock options 2 (c) 2 (c) 2 (c) 2 (c) RSUs 323 (d) 112 (e) 289 (d) 50 (e) Denominator for earnings per common share – diluted: Weighted average number of common and common equivalent shares outstanding 237,108 236,553 236,983 236,400 (a) Excludes 587 shares of unvested restricted common stock as of September 30, 2016 , which equate to 596 and 657 shares, respectively, on a weighted average basis for the three and nine months ended September 30, 2016 . These shares will continue to be excluded from the computation of basic EPS until contingencies are resolved and the shares are released. (b) Excludes 848 shares of unvested restricted common stock as of September 30, 2015 , which equate to 818 and 760 shares, respectively, on a weighted average basis for the three and nine months ended September 30, 2015 . These shares were excluded from the computation of basic EPS as the contingencies remained and the shares had not been released as of the end of the reporting period. (c) There were outstanding options to purchase 41 and 53 shares of common stock as of September 30, 2016 and 2015 , respectively, at a weighted average exercise price of $19.33 and $19.39 , respectively. Of these totals, outstanding options to purchase 35 and 45 shares of common stock as of September 30, 2016 and 2015 , respectively, at a weighted average exercise price of $20.63 and $20.74 , respectively, have been excluded from the common shares used in calculating diluted earnings per share as including them would be anti-dilutive. (d) There were 391 RSUs eligible for future conversion following the performance periods as of September 30, 2016 (see Note 5 to the condensed consolidated financial statements), which equate to 391 and 360 RSUs on a weighted average basis for the three and nine months ended September 30, 2016 , respectively. These contingently issuable shares are included in diluted EPS based on the weighted average number of shares that would be outstanding during the period, if any, assuming the end of the reporting period was the end of the contingency periods. (e) There were 180 RSUs eligible for future conversion following the performance period as of September 30, 2015 , which equate to 168 and 76 RSUs on a weighted average basis for the three and nine months ended September 30, 2015 , respectively. These contingently issuable shares are included in diluted EPS based on the weighted average number of shares that would have been outstanding during the period, if any, assuming September 30, 2015 was the end of the contingency period.

Provision for Impairment of I34

Provision for Impairment of Investment Properties (Tables)	9 Months Ended
	Sep. 30, 2016
Impairment or Disposal of Tangible Assets Disclosure [Abstract]
Schedule of identified impairment indicators	As of September 30, 2016 and 2015 , the Company identified indicators of impairment at certain of its properties. Such indicators included a low occupancy rate, difficulty in leasing space and related cost of re-leasing, financially troubled tenants or reduced anticipated holding periods. The following table summarizes the results of these analyses as of September 30, 2016 and 2015 : September 30, 2016 September 30, 2015 Number of properties for which indicators of impairment were identified 5 3 (a) Less: number of properties for which an impairment charge was recorded 1 — Less: number of properties that were held for sale as of the date the analysis was performed for which indicators of impairment were identified but no impairment charge was recorded 1 — Remaining properties for which indicators of impairment were identified but no impairment charge was considered necessary 3 3 Weighted average percentage by which the projected undiscounted cash flows exceeded its respective carrying value for each of the remaining properties 14 % 39 % (a) Includes two properties which have subsequently been sold as of September 30, 2016 .
Schedule of investment property impairment charges	The Company recorded the following investment property impairment charges during the nine months ended September 30, 2016 : Property Name Property Type Impairment Date Square Footage Provision for Impairment of Investment Properties South Billings Center (a) Development March 31, 2016 — $ 2,164 Mid-Hudson Center (b) Multi-tenant retail June 30, 2016 235,600 4,142 Saucon Valley Square (c) Multi-tenant retail September 30, 2016 80,700 4,742 $ 11,048 Estimated fair value of impaired properties as of impairment date $ 37,100 (a) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract, which was subsequently terminated. The property was not under active development as of September 30, 2016 . (b) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract. This property was classified as held for sale as of June 30, 2016 and was sold on July 21, 2016. (c) The Company recorded an impairment charge driven by a change in the estimated holding period for the property. The Company recorded the following investment property impairment charges during the nine months ended September 30, 2015 : Property Name Property Type Impairment Date Square Footage Provision for Impairment of Investment Properties Massillon Commons (a) Multi-tenant retail June 4, 2015 245,900 $ 2,289 Traveler’s Office Building (b) Single-user office June 30, 2015 50,800 1,655 Shaw’s Supermarket (a) Single-user retail August 6, 2015 65,700 169 $ 4,113 Estimated fair value of impaired properties as of impairment date $ 20,970 (a) The Company recorded impairment charges based upon the terms and conditions of an executed sales contract for the respective properties, which were sold during 2015. (b) The Company recorded an impairment charge based upon the terms and conditions of an executed sales contract. This property was classified as held for sale as of June 30, 2015 and was sold on July 30, 2015.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Schedule of carrying value and estimated fair value of financial instruments	The following table presents the carrying value and estimated fair value of the Company’s financial instruments: September 30, 2016 December 31, 2015 Carrying Value Fair Value Carrying Value Fair Value Financial assets: Derivative asset $ 138 $ 138 $ — $ — Financial liabilities: Mortgages payable, net $ 1,000,089 $ 1,094,472 $ 1,123,136 $ 1,213,620 Unsecured notes payable, net $ 595,479 $ 617,473 $ 495,576 $ 486,701 Unsecured term loans, net $ 447,302 $ 450,000 $ 447,526 $ 450,000 Unsecured revolving line of credit $ — $ — $ 100,000 $ 100,000 Derivative liability $ — $ — $ 85 $ 85 The carrying value of the derivative asset is included in “Other assets, net” and the carrying value of the derivative liability is included in “Other liabilities” in the accompanying condensed consolidated balance sheets.
Schedule of financial instruments measured at fair value on a recurring basis	The following table presents the Company’s financial instruments, which are measured at fair value on a recurring basis, by the level in the fair value hierarchy within which those measurements fall. Methods and assumptions used to estimate the fair value of these instruments are described after the table. Fair Value Level 1 Level 2 Level 3 Total September 30, 2016 Derivative asset $ — $ 138 $ — $ 138 December 31, 2015 Derivative liability $ — $ 85 $ — $ 85
Schedule of assets measured at fair value on a nonrecurring basis	The following table presents the Company’s assets measured at fair value on a nonrecurring basis as of September 30, 2016 aggregated by the level within the fair value hierarchy in which those measurements fall. The table includes information related to properties remeasured to fair value during the nine months ended September 30, 2016 , except for those properties sold prior to September 30, 2016 . Methods and assumptions used to estimate the fair value of these assets are described after the table. Fair Value Level 1 Level 2 Level 3 Total Provision for Impairment (a) September 30, 2016 Investment properties $ — $ 3,000 (b) $ 6,600 (c) $ 9,600 $ 6,906 (a) Excludes impairment charges recorded on investment properties sold prior to September 30, 2016. (b) Represents the fair value of the Company’s South Billings Center development property, which was not under active development during the nine months ended September 30, 2016 . The estimated fair value of South Billings Center was based upon the expected sales price from the executed sales contract, which was subsequently terminated, and determined to be a Level 2 input. (c) Represents the fair value of the Company’s Saucon Valley Square investment property. The estimated fair value of Saucon Valley Square was determined using the income approach. The income approach involves discounting the estimated income stream and reversion (presumed sale) value of a property over an estimated holding period to a present value at a risk-adjusted rate. Discount rates, growth assumptions and terminal capitalization rates utilized in this approach are derived from property-specific information, market transactions and other financial and industry data. The terminal capitalization rate and discount rate are significant inputs to this valuation. The following are the key Level 3 inputs used in estimating the fair value of Saucon Valley Square as of September 30, 2016 , the date the asset was measured at fair value: Saucon Valley Square Rental growth rates Varies (i) Operating expense growth rate 3.10% Discount rate 9.35% Terminal capitalization rate 8.35% (i) Since cash flow models are established at the tenant level, projected rental revenue growth rates fluctuate over the course of the estimated holding period based upon the timing of lease rollover, amount of available space and other property and space-specific factors. The Company did not have any assets measured at fair value on a nonrecurring basis as of December 31, 2015.
Schedule of financial liabilities measured at fair value for disclosure purposes	The following table presents the Company’s financial liabilities, which are measured at fair value for disclosure purposes, by the level in the fair value hierarchy within which those measurements fall. Methods and assumptions used to estimate the fair value of these instruments are described after the table. Fair Value Level 1 Level 2 Level 3 Total September 30, 2016 Mortgages payable, net $ — $ — $ 1,094,472 $ 1,094,472 Unsecured notes payable, net $ 249,908 $ — $ 367,565 $ 617,473 Unsecured term loans, net $ — $ — $ 450,000 $ 450,000 December 31, 2015 Mortgages payable, net $ — $ — $ 1,213,620 $ 1,213,620 Unsecured notes payable, net $ 239,482 $ — $ 247,219 $ 486,701 Unsecured term loans, net $ — $ — $ 450,000 $ 450,000 Unsecured revolving line of credit $ — $ — $ 100,000 $ 100,000

Organization and Basis of Pre36

Organization and Basis of Presentation (Details)	Sep. 30, 2016propertysubsidiary
Real Estate Properties [Line Items]
Number of wholly-owned subsidiaries jointly elected to be treated as a TRS | subsidiary	1
Operating properties | Wholly-owned
Real Estate Properties [Line Items]
Number of real estate properties owned	175
Operating properties | Wholly-owned | Retail
Real Estate Properties [Line Items]
Number of real estate properties owned	174
Operating properties | Wholly-owned | Office
Real Estate Properties [Line Items]
Number of real estate properties owned	1
Development properties | Wholly-owned
Real Estate Properties [Line Items]
Number of real estate properties owned	2
Investment properties held for sale | Operating properties | Wholly-owned
Real Estate Properties [Line Items]
Number of real estate properties owned	1

Summary of Significant Accoun37

Summary of Significant Accounting Policies (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016property	Jan. 01, 2016USD ($)
Accounting Policies [Abstract]
Cumulative effect of accounting change | $		$ 17
VIE
Variable Interest Entity [Line Items]
Number of properties acquired | property	3

Acquisitions _ Summary of Acqui

Acquisitions – Summary of Acquisitions (Details) $ in Thousands

Aug. 30, 2016USD ($)ft²

Jun. 15, 2016USD ($)ft²

May 05, 2016USD ($)ft²

Apr. 29, 2016USD ($)ft²

Apr. 01, 2016USD ($)ft²

Mar. 29, 2016USD ($)ft²

Jan. 15, 2016USD ($)ft²property

Aug. 27, 2015USD ($)ft²

Jul. 31, 2015USD ($)ft²

Jun. 10, 2015USD ($)ft²

May 04, 2015USD ($)ft²

Mar. 24, 2015USD ($)ft²

Feb. 19, 2015USD ($)ft²

Jan. 23, 2015USD ($)ft²

Jan. 08, 2015USD ($)ft²

Sep. 30, 2016USD ($)ft²

Sep. 30, 2015USD ($)ft²

Sep. 30, 2016USD ($)ft²

Sep. 30, 2015USD ($)ft²

Business Acquisition [Line Items]

Gain on extinguishment of other liabilities

$ 0

$ 0

$ 6,978

$ 0

Shoppes at Hagerstown

Business Acquisition [Line Items]

Square footage | ft²

113,000

Acquisition price

$ 27,055

Merrifield Town Center II

Business Acquisition [Line Items]

Square footage | ft²

138,000

Acquisition price

$ 45,676

Oak Brook Promenade

Business Acquisition [Line Items]

Square footage | ft²

183,200

Acquisition price

$ 65,954

The Shoppes at Union Hill

Business Acquisition [Line Items]

Square footage | ft²

91,700

Acquisition price

$ 63,060

Mortgage debt assumed

$ 15,971

$ 15,971

$ 15,971

Fixed interest rate (as a percent)

3.75%

3.75%

3.75%

Ashland & Roosevelt – Fee Interest

Business Acquisition [Line Items]

Square footage | ft²

0

Purchase price of asset acquisition

$ 13,850

Gain on extinguishment of other liabilities

$ 6,978

Tacoma South

Business Acquisition [Line Items]

Square footage | ft²

230,700

Acquisition price

$ 39,400

Eastside

Business Acquisition [Line Items]

Square footage | ft²

67,100

Acquisition price

$ 23,842

Woodinville Plaza – Anchor Space Improvements

Business Acquisition [Line Items]

Square footage | ft²

0

Purchase price of asset acquisition

$ 4,500

2016 acquisitions

Business Acquisition [Line Items]

Square footage | ft²

761,700

761,700

Acquisition price

$ 283,337

Mortgage debt assumed

$ 15,316

$ 15,316

Shoppes at Hagerstown and Merrifield Town Center II

Business Acquisition [Line Items]

Number of properties acquired | property

2

Downtown Crown

Business Acquisition [Line Items]

Square footage | ft²

258,000

Acquisition price

$ 162,785

Merrifield Town Center

Business Acquisition [Line Items]

Square footage | ft²

84,900

Acquisition price

$ 56,500

Fort Evans Plaza II

Business Acquisition [Line Items]

Square footage | ft²

228,900

Acquisition price

$ 65,000

Cedar Park Town Center

Business Acquisition [Line Items]

Square footage | ft²

179,300

Acquisition price

$ 39,057

Parcel at Lake Worth Towne Crossing

Business Acquisition [Line Items]

Square footage | ft²

0

Purchase price of asset acquisition

$ 400

Tysons Corner

Business Acquisition [Line Items]

Square footage | ft²

37,700

Acquisition price

$ 31,556

Woodinville Plaza

Business Acquisition [Line Items]

Square footage | ft²

170,800

Acquisition price

$ 35,250

Outparcel at Southlake Town Square

Business Acquisition [Line Items]

Square footage | ft²

13,800

Acquisition price

$ 8,440

Coal Creek Marketplace

Business Acquisition [Line Items]

Square footage | ft²

55,900

Acquisition price

$ 17,600

2015 acquisitions

Business Acquisition [Line Items]

Square footage | ft²

1,029,300

1,029,300

Acquisition price

$ 416,588

Mortgage debt assumed

$ 0

$ 0

Retail | Merrifield Town Center II

Business Acquisition [Line Items]

Square footage | ft²

76,000

Storage | Merrifield Town Center II

Business Acquisition [Line Items]

Square footage | ft²

62,000

Acquisitions _ Acquisition Date

Acquisitions – Acquisition Date Fair Values (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Acquisition date fair values
Total revenues	$ 144,526	$ 150,955	$ 440,391	$ 455,040
Net income attributable to common shareholders	70,132	75,967	141,435	115,002
2016 acquisitions
Acquisition date fair values
Land	84,720		84,720
Building and other improvements	176,937		176,937
Acquired lease intangible assets	25,016		25,016
Acquired lease intangible liabilities	(3,991)		(3,991)
Mortgages payable, net	(15,316)		(15,316)
Net assets acquired	267,366		$ 267,366
Weighted average amortization period, acquired lease intangible assets			6 years
Weighted average amortization period, acquired lease intangible liabilities			11 years
Transaction costs	$ 913		$ 913
2015 acquisitions
Acquisition date fair values
Land		146,107		146,107
Building and other improvements		254,377		254,377
Acquired lease intangible assets		39,986		39,986
Acquired lease intangible liabilities		(23,882)		(23,882)
Mortgages payable, net		0		0
Net assets acquired		416,588		$ 416,588
Weighted average amortization period, acquired lease intangible assets				15 years
Weighted average amortization period, acquired lease intangible liabilities				21 years
Transaction costs		$ 1,297		$ 1,297
Total revenues				41,169
Net income attributable to common shareholders				$ 7,575
2015 and 2016 acquisitions
Acquisition date fair values
Total revenues			36,210
Net income attributable to common shareholders			$ 7,760

Acquisitions _ Condensed Pro Fo

Acquisitions – Condensed Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Unaudited condensed pro forma financial information
Total revenues	$ 144,526	$ 156,158	$ 444,622	$ 473,387
Net income	72,494	77,232	147,421	118,753
Net income attributable to common shareholders	$ 70,132	$ 74,870	$ 140,334	$ 111,666
Earnings per common share – basic and diluted
Net income per common share attributable to common shareholders	$ 0.30	$ 0.32	$ 0.59	$ 0.47
Weighted average number of common shares outstanding – basic	236,783	236,439	236,692	236,348

Acquisitions _ Variable Interes

Acquisitions – Variable Interest Entities (Details) - VIE $ in Thousands	Sep. 30, 2016USD ($)days
Variable Interest Entity [Line Items]
Number of days to complete tax-deferred exchange | days	180
Oak Brook Promenade
Variable Interest Entity [Line Items]
Amount loaned to VIE for acquisition	$ 65,419
Tacoma South
Variable Interest Entity [Line Items]
Amount loaned to VIE for acquisition	39,215
Eastside
Variable Interest Entity [Line Items]
Amount loaned to VIE for acquisition	$ 23,522

Dispositions _ Summary of Dispo

Dispositions – Summary of Dispositions (Details) $ in Thousands

Sep. 09, 2016USD ($)ft²

Aug. 22, 2016USD ($)ft²

Aug. 18, 2016USD ($)ft²

Aug. 12, 2016USD ($)ft²

Aug. 05, 2016USD ($)ft²

Aug. 04, 2016USD ($)ft²

Jul. 29, 2016USD ($)ft²

Jul. 27, 2016USD ($)ft²

Jul. 21, 2016USD ($)ft²

Jul. 08, 2016USD ($)ft²

Jun. 23, 2016USD ($)ft²property

Jun. 15, 2016USD ($)ft²

Jun. 02, 2016USD ($)ft²

Apr. 20, 2016USD ($)ft²

Mar. 30, 2016USD ($)ft²property

Feb. 10, 2016USD ($)ft²

Feb. 01, 2016USD ($)ft²

Sep. 29, 2015USD ($)ft²

Sep. 15, 2015USD ($)ft²

Aug. 31, 2015USD ($)ft²

Aug. 24, 2015USD ($)ft²

Aug. 06, 2015USD ($)ft²

Jul. 30, 2015USD ($)ft²

Jul. 28, 2015USD ($)ft²

Jul. 17, 2015USD ($)ft²

Jun. 17, 2015USD ($)ft²

Jun. 05, 2015USD ($)ft²

Jun. 04, 2015USD ($)ft²

May 15, 2015USD ($)ft²

Apr. 30, 2015USD ($)ft²

Apr. 07, 2015USD ($)ft²

Feb. 27, 2015USD ($)ft²

Jan. 20, 2015USD ($)ft²

Sep. 30, 2016USD ($)ft²

Sep. 30, 2015USD ($)ft²

Jun. 30, 2016USD ($)

Sep. 30, 2016USD ($)ft²

Sep. 30, 2015USD ($)ft²

Dec. 31, 2015USD ($)

Property Dispositions [Line Items]

Aggregate proceeds, net

$ 307,355

$ 395,207

Gain

97,737

113,214

Mortgage obligation

$ 1,000,089

1,000,089

$ 1,123,136

Loan obligation assumed by the buyer

15,316

0

Gain on extinguishment of debt

0

$ 0

13,653

$ 0

The Gateway

Property Dispositions [Line Items]

Square footage | ft²

623,200

Consideration

$ 75,000

Net payment for disposition

(795)

Gain

3,868

Mortgage obligation

94,353

$ 94,353

94,353

Loan obligation assumed by the buyer

75,000

75,000

Gain on extinguishment of debt

$ 13,653

$ 13,653

Stateline Station

Property Dispositions [Line Items]

Square footage | ft²

142,600

Consideration

$ 17,500

Aggregate proceeds, net

17,210

Gain

$ 4,253

Six Property Portfolio

Property Dispositions [Line Items]

Square footage | ft²

230,400

Consideration

$ 35,413

Aggregate proceeds, net

34,986

Gain

$ 13,618

Number of properties sold | property

6

Proceeds temporarily restricted related to tax-deferred exchanges

$ 34,973

CVS Pharmacy – Oklahoma City

Property Dispositions [Line Items]

Square footage | ft²

10,900

Consideration

$ 4,676

Aggregate proceeds, net

4,608

Gain

$ 1,764

Rite Aid Store (Eckerd) – Canandaigua & Tim Horton Donut Shop

Property Dispositions [Line Items]

Square footage | ft²

16,600

Consideration

$ 5,400

Aggregate proceeds, net

5,333

Gain

$ 1,444

Academy Sports – Midland

Property Dispositions [Line Items]

Square footage | ft²

61,200

Consideration

$ 5,541

Aggregate proceeds, net

5,399

Gain

2,220

Proceeds temporarily restricted related to tax-deferred exchanges

$ 5,383

Four Rite Aid Portfolio

Property Dispositions [Line Items]

Square footage | ft²

45,400

Consideration

$ 15,934

Aggregate proceeds, net

14,646

Gain

$ 2,287

Number of properties sold | property

4

Broadway Shopping Center

Property Dispositions [Line Items]

Square footage | ft²

190,300

Consideration

$ 20,500

Aggregate proceeds, net

20,103

Gain

$ 7,958

Mid-Hudson Center

Property Dispositions [Line Items]

Square footage | ft²

235,600

Consideration

$ 27,500

Aggregate proceeds, net

25,615

Gain

$ 0

Rite Aid Store (Eckerd), Main St. – Buffalo

Property Dispositions [Line Items]

Square footage | ft²

10,900

Consideration

$ 3,388

Aggregate proceeds, net

3,296

Gain

$ 344

Rite Aid Store (Eckerd) – Lancaster

Property Dispositions [Line Items]

Square footage | ft²

10,900

Consideration

$ 3,425

Aggregate proceeds, net

3,349

Gain

$ 625

Alison's Corner

Property Dispositions [Line Items]

Square footage | ft²

55,100

Consideration

$ 7,850

Aggregate proceeds, net

7,559

Gain

$ 3,334

Rite Aid Store (Eckerd) – Lake Ave.

Property Dispositions [Line Items]

Square footage | ft²

13,200

Consideration

$ 5,400

Aggregate proceeds, net

5,334

Gain

$ 907

Maple Tree Place

Property Dispositions [Line Items]

Square footage | ft²

489,000

Consideration

$ 90,000

Aggregate proceeds, net

87,047

Gain

$ 15,566

CVS Pharmacy – Burleson

Property Dispositions [Line Items]

Square footage | ft²

10,900

Consideration

$ 4,190

Aggregate proceeds, net

4,102

Gain

$ 1,425

Mitchell Ranch Plaza

Property Dispositions [Line Items]

Square footage | ft²

199,600

Consideration

$ 55,625

Aggregate proceeds, net

54,305

Gain

$ 33,612

Rite Aid Store (Eckerd), E. Main St. – Batavia

Property Dispositions [Line Items]

Square footage | ft²

13,800

Consideration

$ 5,050

Aggregate proceeds, net

4,924

Gain

$ 1,249

Rite Aid Store (Eckerd) – Lockport

Property Dispositions [Line Items]

Square footage | ft²

13,800

Consideration

$ 4,690

Aggregate proceeds, net

4,415

Gain

$ 753

Rite Aid Store (Eckerd), Ferry St. – Buffalo

Property Dispositions [Line Items]

Square footage | ft²

10,900

Consideration

$ 3,600

Aggregate proceeds, net

3,370

Gain

$ 612

2016 dispositions

Property Dispositions [Line Items]

Square footage | ft²

2,384,300

2,384,300

Consideration

$ 390,682

$ 390,682

Aggregate proceeds, net

304,806

Gain

95,839

Outparcel at Beachway Plaza

Property Dispositions [Line Items]

Consideration

$ 2,639

2,639

Gain

$ 1,898

Proceeds temporarily restricted related to tax-deferred exchanges

$ 2,549

Aon Hewitt East Campus

Property Dispositions [Line Items]

Square footage | ft²

343,000

Consideration

$ 17,233

Aggregate proceeds, net

16,495

Gain

$ 0

Promenade at Red Cliff

Property Dispositions [Line Items]

Square footage | ft²

94,500

Consideration

$ 19,050

Aggregate proceeds, net

18,848

Gain

$ 4,572

Hartford Insurance Building

Property Dispositions [Line Items]

Square footage | ft²

97,400

Consideration

$ 6,015

Aggregate proceeds, net

5,663

Gain

$ 860

Rasmussen College

Property Dispositions [Line Items]

Square footage | ft²

26,700

Consideration

$ 4,800

Aggregate proceeds, net

4,449

Gain

$ 1,334

Mountain View Plaza

Property Dispositions [Line Items]

Square footage | ft²

162,000

Consideration

$ 28,500

Aggregate proceeds, net

27,949

Gain

$ 10,184

Massillon Commons

Property Dispositions [Line Items]

Square footage | ft²

245,900

Consideration

$ 12,520

Aggregate proceeds, net

12,145

Gain

$ 0

Citizen's Property Insurance Building

Property Dispositions [Line Items]

Square footage | ft²

59,800

Consideration

$ 3,650

Aggregate proceeds, net

3,368

Gain

$ 440

Pine Ridge Plaza

Property Dispositions [Line Items]

Square footage | ft²

236,500

Consideration

$ 33,200

Aggregate proceeds, net

31,858

Gain

$ 12,938

Bison Hollow

Property Dispositions [Line Items]

Square footage | ft²

134,800

Consideration

$ 18,800

Aggregate proceeds, net

18,657

Gain

$ 4,061

The Village at Quail Springs

Property Dispositions [Line Items]

Square footage | ft²

100,400

Consideration

$ 11,350

Aggregate proceeds, net

11,267

Gain

$ 3,824

Greensburg Commons

Property Dispositions [Line Items]

Square footage | ft²

272,500

Consideration

$ 18,400

Aggregate proceeds, net

18,283

Gain

$ 2,810

Arvada Connection and Arvada Marketplace

Property Dispositions [Line Items]

Square footage | ft²

367,500

Consideration

$ 54,900

Aggregate proceeds, net

53,159

Gain

$ 20,208

Traveler's Office Building

Property Dispositions [Line Items]

Square footage | ft²

50,800

Consideration

$ 4,841

Aggregate proceeds, net

4,643

Gain

$ 0

Shaw's Supermarket

Property Dispositions [Line Items]

Square footage | ft²

65,700

Consideration

$ 3,000

Aggregate proceeds, net

2,769

Gain

$ 0

Harvest Towne Center

Property Dispositions [Line Items]

Square footage | ft²

39,700

Consideration

$ 7,800

Aggregate proceeds, net

7,381

Gain

$ 1,217

Trenton Crossing & McAllen Shopping Center

Property Dispositions [Line Items]

Square footage | ft²

265,900

Consideration

$ 39,295

Aggregate proceeds, net

38,410

Gain

$ 13,760

The Shops at Boardwalk

Property Dispositions [Line Items]

Square footage | ft²

122,400

Consideration

$ 27,400

Aggregate proceeds, net

26,634

Gain

$ 3,146

Best on the Boulevard

Property Dispositions [Line Items]

Square footage | ft²

204,400

Consideration

$ 42,500

Aggregate proceeds, net

41,542

Gain

$ 15,932

Montecito Crossing

Property Dispositions [Line Items]

Square footage | ft²

179,700

Consideration

$ 52,200

Aggregate proceeds, net

51,415

Gain

$ 17,928

2015 dispositions

Property Dispositions [Line Items]

Square footage | ft²

3,069,600

3,069,600

Consideration

$ 405,454

$ 405,454

Aggregate proceeds, net

394,935

Gain

113,214

Condemnation proceeds

$ 272

Dispositions _ Assets and Liabi

Dispositions – Assets and Liabilities of Investment Properties Held for Sale (Details) $ in Thousands	Sep. 30, 2016USD ($)ft²	Dec. 31, 2015USD ($)
Assets
Assets associated with investment properties held for sale	$ 3,581	$ 0
Liabilities
Liabilities associated with investment properties held for sale	36	$ 0
Investment properties held for sale
Assets
Land, building and other improvements	5,524
Accumulated depreciation	(2,042)
Net investment properties	3,482
Other assets	99
Assets associated with investment properties held for sale	3,581
Liabilities
Other liabilities	36
Liabilities associated with investment properties held for sale	$ 36
Walgreens - Northwoods | Investment properties held for sale
Long Lived Assets Held-for-sale [Line Items]
Square footage | ft²	16,300

Equity Compensation Plans (Deta

Equity Compensation Plans (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Equity Instruments, Nonvested [Roll Forward]
Balance at the end of the period (in shares)	587	587	848	587	848
Restricted shares
Share-based Compensation Arrangement [Line Items]
Additional compensation expense					$ 1,680
Number of restricted shares in which vesting was accelerated					134
Fair value of restricted shares vested				$ 6,830
Equity Instruments, Nonvested [Roll Forward]
Balance at the beginning of the period (in shares)				788
Shares/RSUs granted (in shares)				269
Shares vested (in shares)				(460)
Shares/RSUs forfeited (in shares)				(10)
Balance at the end of the period (in shares)	587	587		587
Equity Instruments, Nonvested, Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)				$ 15.52
Shares/RSUs granted (in dollars per share)				14.74
Shares vested (in dollars per share)				15.48
Shares/RSUs forfeited (in dollars per share)				14.70
Balance at the end of the period (in dollars per share)	$ 15.21	$ 15.21		$ 15.21
Compensation Cost Not Yet Recognized
Total unrecognized compensation expense	$ 4,120	$ 4,120		$ 4,120
RSUs
Share-based Compensation Arrangement [Line Items]
Vesting period for shares/RSUs granted				1 year
Conversion rate of RSUs into shares of common stock (as a percent)				33.00%
Conversion rate of RSUs into restricted shares (as a percent)				67.00%
Equity Instruments, Nonvested [Roll Forward]
Balance at the beginning of the period (in shares)				174
Shares/RSUs granted (in shares)				246
Shares/RSUs forfeited (in shares)				(29)
Balance at the end of the period (in shares)	391	391		391
Equity Instruments, Nonvested, Weighted Average Grant Date Fair Value
Balance at the beginning of the period (in dollars per share)				$ 14.20
Shares/RSUs granted (in dollars per share)				13.85
Shares/RSUs forfeited (in dollars per share)				13.56
Balance at the end of the period (in dollars per share)	$ 14.02	$ 14.02		$ 14.02
Compensation Cost Not Yet Recognized
Total unrecognized compensation expense	$ 3,861	$ 3,861		$ 3,861
Restricted shares and RSUs
Share-based Compensation Arrangement [Line Items]
Compensation expense		$ 1,594	$ 2,099	$ 5,296	$ 8,225
Stock options
Share-based Compensation Arrangement [Line Items]
Number of options exercised		2
Number of options forfeited		10
Number of options outstanding	41	41	53	41	53
Minimum | Restricted shares
Share-based Compensation Arrangement [Line Items]
Vesting period for shares/RSUs granted				5 months
Minimum | RSUs
Share-based Compensation Arrangement [Line Items]
Conversion rate of RSUs if threshold met (as a percent)				50.00%
Maximum | Restricted shares
Share-based Compensation Arrangement [Line Items]
Vesting period for shares/RSUs granted				3 years 11 months
Maximum | RSUs
Share-based Compensation Arrangement [Line Items]
Conversion rate of RSUs if threshold met (as a percent)				200.00%
Weighted average | Restricted shares
Compensation Cost Not Yet Recognized
Unrecognized compensation expense, period for recognition (in years)	1 year 5 months
Weighted average | RSUs
Share-based Compensation Arrangement [Line Items]
Risk-free interest rate (as a percent)				0.89%
Common stock dividend yield (as a percent)				4.59%
Compensation Cost Not Yet Recognized
Unrecognized compensation expense, period for recognition (in years)	2 years 8 months 15 days

Mortgages Payable _ Summary (De

Mortgages Payable – Summary (Details) $ in Thousands	Sep. 30, 2016USD ($)propertyloan	Feb. 01, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2016USD ($)propertyloan	Sep. 30, 2015USD ($)	Sep. 30, 2016USD ($)propertyloan	Sep. 30, 2015USD ($)	Apr. 01, 2016USD ($)
Debt Instrument [Line Items]
Fixed rate mortgages payable	$ 2,054,879			$ 2,054,879		$ 2,054,879
Weighted average interest rate (as a percent)	4.61%			4.61%		4.61%
Mortgage obligation	$ 1,000,089		$ 1,123,136	$ 1,000,089		$ 1,000,089
Loan obligation assumed by the buyer						15,316	$ 0
Gain on extinguishment of debt				0	$ 0	13,653	$ 0
Fixed rate debt
Debt Instrument [Line Items]
Fixed rate mortgages payable	$ 1,854,879			$ 1,854,879		$ 1,854,879
Weighted average interest rate (as a percent)	4.90%			4.90%		4.90%
Mortgages payable
Debt Instrument [Line Items]
Premium, net of accumulated amortization	$ 1,544		1,865	$ 1,544		$ 1,544
Discount, net of accumulated amortization	(633)		(1)	(633)		(633)
Capitalized loan fees, net of accumulated amortization	(5,701)		(7,233)	(5,701)		(5,701)
Mortgages payable, net	1,000,089		1,123,136	1,000,089		1,000,089
Variable rate debt swapped to fixed rate			7,910
Mortgages payable | Fixed rate debt
Debt Instrument [Line Items]
Fixed rate mortgages payable	$ 1,004,879		$ 1,128,505	$ 1,004,879		$ 1,004,879
Weighted average interest rate (as a percent)	6.06%		6.08%	6.06%		6.06%
Weighted average years to maturity	3 years 8 months 15 days		3 years 11 months
IW JV 2009, LLC
Debt Instrument [Line Items]
Cross-collateralized mortgage balance	$ 391,436			$ 391,436		$ 391,436
Number of properties in cross-collateralized mortgage | property	48			48		48
Minimum | Mortgages payable | Fixed rate debt
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	3.50%		3.35%	3.50%		3.50%
Maximum | Mortgages payable | Fixed rate debt
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	8.00%		8.00%	8.00%		8.00%
The Gateway
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	6.57%			6.57%		6.57%
Mortgage obligation	$ 94,353	$ 94,353		$ 94,353		$ 94,353
Loan obligation assumed by the buyer		75,000				75,000
Gain on extinguishment of debt		$ 13,653				13,653
Debt repaid | Mortgages payable
Debt Instrument [Line Items]
Variable rate debt swapped to fixed rate	7,750			7,750		7,750
Amount of mortgages payable repaid						35,344
Scheduled principal payments related to amortizing loans	$ 9,900			$ 9,900		$ 9,900
Number of mortgages with an interest rate swap | loan	1			1		1
Debt repaid | Weighted average | Mortgages payable
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	4.34%			4.34%		4.34%
The Shoppes at Union Hill
Debt Instrument [Line Items]
Fixed interest rate (as a percent)	3.75%			3.75%		3.75%		3.75%
Mortgage debt assumed	$ 15,971			$ 15,971		$ 15,971		$ 15,971

Mortgages Payable _ Debt Maturi

Mortgages Payable – Debt Maturities (Details) $ in Thousands	Dec. 28, 2016USD ($)	Sep. 30, 2016USD ($)instrument	Dec. 31, 2015USD ($)
Long-term Debt, Fiscal Year Maturity
2,016		$ 2,865
2,017		227,451
2,018		211,647
2,019		444,324
2,020		4,334
Thereafter		1,164,258
Total		$ 2,054,879
Long-term Debt, Weighted Average Interest Rate
2,016		7.18%
2,017		5.08%
2,018		2.22%
2,019		7.49%
2,020		4.58%
Thereafter		3.85%
Total		4.61%
Mortgages payable
Debt Instrument [Line Items]
Premium, net of accumulated amortization		$ 1,544	$ 1,865
Discount, net of accumulated amortization		(633)	(1)
Variable rate debt swapped to fixed rate			7,910
Capitalized loan fees, net of accumulated amortization		(5,701)	(7,233)
Unsecured notes payable
Debt Instrument [Line Items]
Discount, net of accumulated amortization		(1,001)	(1,090)
Capitalized loan fees, net of accumulated amortization		(3,520)	$ (3,334)
Consolidated indebtedness
Debt Instrument [Line Items]
Capitalized loan fees, net of accumulated amortization		$ (11,919)
Weighted average years to maturity		4 years 10 months
Fixed rate debt
Long-term Debt, Fiscal Year Maturity
2,016		$ 2,865
2,017		227,451
2,018		11,647
2,019		444,324
2,020		4,334
Thereafter		1,164,258
Total		$ 1,854,879
Long-term Debt, Weighted Average Interest Rate
2,016		7.18%
2,017		5.08%
2,018		6.52%
2,019		7.49%
2,020		4.58%
Thereafter		3.85%
Total		4.90%
Fixed rate debt | Mortgages payable
Debt Instrument [Line Items]
Weighted average years to maturity		3 years 8 months 15 days	3 years 11 months
Long-term Debt, Fiscal Year Maturity
2,016		$ 2,865
2,017		227,451
2,018		11,647
2,019		444,324
2,020		4,334
Thereafter		314,258
Total		$ 1,004,879	$ 1,128,505
Long-term Debt, Weighted Average Interest Rate
Total		6.06%	6.08%
Fixed rate debt | Unsecured credit facility
Long-term Debt, Fiscal Year Maturity
2,016		$ 0
2,017		0
2,018		0
2,019		0
2,020		0
Thereafter		250,000
Total		250,000
Fixed rate debt | Unsecured notes payable
Long-term Debt, Fiscal Year Maturity
2,016		0
2,017		0
2,018		0
2,019		0
2,020		0
Thereafter		600,000
Total		600,000
Variable rate debt
Long-term Debt, Fiscal Year Maturity
2,016		0
2,017		0
2,018		200,000
2,019		0
2,020		0
Thereafter		0
Total		$ 200,000
Long-term Debt, Weighted Average Interest Rate
2,016		0.00%
2,017		0.00%
2,018		1.97%
2,019		0.00%
2,020		0.00%
Thereafter		0.00%
Total		1.97%
Variable rate debt | Unsecured credit facility
Long-term Debt, Fiscal Year Maturity
2,016		$ 0
2,017		0
2,018		200,000
2,019		0
2,020		0
Thereafter		0
Total		200,000
$100,000 and $150,000 interest rate swaps maturing in 2017
Debt Instrument [Line Items]
Variable rate debt swapped to fixed rate		$ 250,000
Number of instruments | instrument		2
LIBOR | $100,000 and $150,000 interest rate swaps maturing in 2017
Debt Instrument [Line Items]
Reference rate for variable interest rate		one-month floating rate LIBOR
Weighted average | $100,000 and $150,000 interest rate swaps maturing in 2017
Debt Instrument [Line Items]
Fixed interest rate (as a percent)		0.6677%
Subsequent events | 4.24% Notes Due 2028 | Unsecured notes payable
Debt Instrument [Line Items]
Amount of debt issuance	$ 100,000
Term of debt issuance	12 years
Stated interest rate (as a percent)	4.24%

Unsecured Notes Payable (Detail

Unsecured Notes Payable (Details) - USD ($) $ in Thousands	Dec. 28, 2016	Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Principal balance		$ 595,479	$ 495,576
Senior Notes
Debt Instrument [Line Items]
Principal balance		600,000	500,000
Discount, net of accumulated amortization		(1,001)	(1,090)
Capitalized loan fees, net of accumulated amortization		$ (3,520)	$ (3,334)
Weighted average interest rate (as a percent)		4.18%	4.20%
Senior Notes | 4.12% Notes Due 2021
Debt Instrument [Line Items]
Principal balance		$ 100,000	$ 100,000
Stated interest rate (as a percent)		4.12%	4.12%
Senior Notes | 4.58% Notes Due 2024
Debt Instrument [Line Items]
Principal balance		$ 150,000	$ 150,000
Stated interest rate (as a percent)		4.58%	4.58%
Senior Notes | 4.00% Notes Due 2025
Debt Instrument [Line Items]
Principal balance		$ 250,000	$ 250,000
Stated interest rate (as a percent)		4.00%	4.00%
Senior Notes | 4.08% Notes Due 2026
Debt Instrument [Line Items]
Principal balance		$ 100,000	$ 0
Stated interest rate (as a percent)		4.08%	0.00%
Amount of debt issuance		$ 100,000
Term of debt issuance		10 years
Subsequent events | Senior Notes | 4.24% Notes Due 2028
Debt Instrument [Line Items]
Stated interest rate (as a percent)	4.24%
Amount of debt issuance	$ 100,000
Term of debt issuance	12 years

Unsecured Credit Facility (Deta

Unsecured Credit Facility (Details) $ in Thousands	Sep. 30, 2016USD ($)	Jan. 06, 2016USD ($)extension_options	Dec. 31, 2015USD ($)	Dec. 31, 2014rating_agency
Line of Credit Facility [Line Items]
Amount borrowed	$ 0		$ 100,000
Unsecured credit facility
Line of Credit Facility [Line Items]
Aggregate borrowing capacity			1,000,000
Amount borrowed	$ 447,302		547,526
Unsecured credit facility | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Aggregate borrowing capacity		$ 1,200,000
Additional borrowing capacity		400,000
Maximum borrowing capacity		1,600,000
Unsecured revolving line of credit
Line of Credit Facility [Line Items]
Aggregate borrowing capacity			550,000
Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Aggregate borrowing capacity		$ 750,000
Number of extension options | extension_options		2
Revolving line of credit, period of extension of maturity (in years)		6 months
Revolving line of credit, extension fee as a percentage of commitment amount		0.075%
$250,000 term loan
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)	1.30%
$250,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Principal amount		$ 250,000
$200,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Principal amount		$ 200,000
Number of extension options | extension_options		2
Term loan, period of extension of maturity (in years)		1 year
Term loan, extension fee as a percentage of amount outstanding		0.15%
Unsecured term loans
Line of Credit Facility [Line Items]
Principal amount			$ 450,000
Variable interest rate spread (as a percent)			1.45%
Amount borrowed	$ 450,000		$ 450,000
Capitalized loan fees, net of accumulated amortization	(2,698)		(2,474)
Term loans, net	447,302		447,526
Fixed rate debt | $250,000 term loan
Line of Credit Facility [Line Items]
Amount borrowed	$ 250,000
Interest rate (as percent)	1.97%
Fixed rate debt | Unsecured term loans
Line of Credit Facility [Line Items]
Amount borrowed			$ 300,000
Interest rate (as percent)			1.99%
Variable rate debt | Unsecured revolving line of credit
Line of Credit Facility [Line Items]
Amount borrowed	$ 0		$ 100,000
Interest rate (as percent)	1.87%		1.93%
Variable rate debt | $200,000 term loan
Line of Credit Facility [Line Items]
Amount borrowed	$ 200,000
Interest rate (as percent)	1.97%
Variable rate debt | Unsecured term loans
Line of Credit Facility [Line Items]
Amount borrowed			$ 150,000
Interest rate (as percent)			1.88%
Investment grade rated
Line of Credit Facility [Line Items]
Number of rating agencies | rating_agency				2
Minimum | Unsecured credit facility
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)			1.45%
Minimum | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Quarterly unused fees (as a percent)		0.15%
Minimum | $250,000 term loan
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)	1.30%
Minimum | Unsecured term loans
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)			1.45%
Minimum | Investment grade rated | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Facility fee (as a percent)		0.125%
Maximum | Unsecured credit facility
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)			2.05%
Maximum | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Quarterly unused fees (as a percent)		0.25%
Maximum | $250,000 term loan
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)	2.20%
Maximum | Unsecured term loans
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)			2.00%
Maximum | Investment grade rated | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Facility fee (as a percent)		0.30%
Weighted average | Unsecured credit facility
Line of Credit Facility [Line Items]
Interest rate (as percent)	1.97%		1.95%
LIBOR | Unsecured credit facility
Line of Credit Facility [Line Items]
Reference rate for variable interest rate		LIBOR	LIBOR
LIBOR | Minimum | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.35%
LIBOR | Minimum | $250,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.30%
LIBOR | Minimum | $200,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.45%
LIBOR | Minimum | Investment grade rated | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		0.85%
LIBOR | Minimum | Investment grade rated | $250,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		0.90%
LIBOR | Minimum | Investment grade rated | $200,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.05%
LIBOR | Maximum | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		2.25%
LIBOR | Maximum | $250,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		2.20%
LIBOR | Maximum | $200,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		2.20%
LIBOR | Maximum | Investment grade rated | Unsecured revolving line of credit | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.55%
LIBOR | Maximum | Investment grade rated | $250,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		1.75%
LIBOR | Maximum | Investment grade rated | $200,000 term loan | KeyBank and Wells Fargo Syndicate
Line of Credit Facility [Line Items]
Variable interest rate spread (as a percent)		2.05%
$100,000 and $150,000 interest rate swaps maturing in 2017
Line of Credit Facility [Line Items]
Variable rate debt swapped to fixed rate	$ 250,000
$100,000 and $150,000 interest rate swaps maturing in 2017 | Weighted average
Line of Credit Facility [Line Items]
Fixed interest rate (as a percent)	0.6677%
$100,000 and $150,000 interest rate swaps maturing in 2017 | LIBOR
Line of Credit Facility [Line Items]
Reference rate for variable interest rate	one-month floating rate LIBOR
$300,000 interest rate swap maturing in 2016
Line of Credit Facility [Line Items]
Variable rate debt swapped to fixed rate			$ 300,000
Fixed interest rate (as a percent)			0.53875%

Derivatives _ Schedule of Deriv

Derivatives – Schedule of Derivative Instruments (Details) $ in Thousands	Sep. 30, 2016USD ($)instrument	Sep. 30, 2016USD ($)instrument	May 16, 2016USD ($)	Mar. 01, 2016USD ($)	Feb. 24, 2016USD ($)	Dec. 31, 2015USD ($)instrument
$100,000 and $150,000 interest rate swaps maturing in 2017
Derivative [Line Items]
Number of instruments | instrument	2	2
Notional	$ 250,000	$ 250,000
$300,000 interest rate swap maturing in 2016
Derivative [Line Items]
Notional						$ 300,000
Fixed interest rate (as a percent)						0.53875%
Cash flow hedges | Interest rate swaps
Derivative [Line Items]
Number of instruments | instrument	2	2				2
Amount of gain (loss) on cash flow hedges expected to be reclassified to interest expense over the next 12 months	$ 34
Notional	$ 250,000	$ 250,000				$ 307,910
Cash flow hedges | $100,000 and $150,000 interest rate swaps maturing in 2017
Derivative [Line Items]
Number of instruments | instrument	2	2
Cash flow hedges | $100,000 interest rate swap maturing in 2017
Derivative [Line Items]
Notional				$ 100,000
Fixed interest rate (as a percent)				0.6591%
Cash flow hedges | $150,000 interest rate swap maturing in 2017
Derivative [Line Items]
Notional			$ 150,000
Fixed interest rate (as a percent)			0.6735%
Cash flow hedges | $300,000 interest rate swap maturing in 2016
Derivative [Line Items]
Notional					$ 300,000
LIBOR | $100,000 and $150,000 interest rate swaps maturing in 2017
Derivative [Line Items]
Reference rate for variable interest rate	one-month floating rate LIBOR
LIBOR | Cash flow hedges | $100,000 and $150,000 interest rate swaps maturing in 2017
Derivative [Line Items]
Reference rate for variable interest rate		one-month floating rate LIBOR
Mortgages payable
Derivative [Line Items]
Notional						7,910
Mortgages payable | Cash flow hedges
Derivative [Line Items]
Notional						$ 7,910
Debt repaid | Mortgages payable
Derivative [Line Items]
Notional	$ 7,750	$ 7,750
Debt repaid | Mortgages payable | Cash flow hedges
Derivative [Line Items]
Notional	$ 7,750	$ 7,750

Derivatives _ Interest Rate Swa

Derivatives – Interest Rate Swaps Designated as Cash Flow Hedges (Details) - Interest rate swaps - Cash flow hedges $ in Thousands	Sep. 30, 2016USD ($)instrument	Dec. 31, 2015USD ($)instrument
Derivative [Line Items]
Number of instruments | instrument	2	2
Notional | $	$ 250,000	$ 307,910

Derivatives _ Estimated Fair Va

Derivatives – Estimated Fair Value (Details) - Interest rate swaps - Cash flow hedges - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Fair value of derivative asset	$ 138	$ 0
Fair value of derivative liability	$ 0	$ 85

Derivatives _ Effect on Stateme

Derivatives – Effect on Statements of Operations (Details) - Interest rate swaps - Cash flow hedges - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Derivative Instruments, (Gain) Loss [Line Items]
Amount of (gain) loss recognized in other comprehensive income on derivative (effective portion)	$ (534)	$ 109	$ 153	$ 691
Amount of loss reclassified from AOCI into income (effective portion)	132	264	342	848
Amount of gain recognized in income on derivative (ineffective portion and amount excluded from effectiveness testing)	$ (38)	$ (4)	$ (35)	$ (25)

Equity (Details)

Equity (Details) - USD ($) $ in Thousands	1 Months Ended	33 Months Ended
	Dec. 31, 2015	Nov. 30, 2015	Sep. 30, 2016
2015 ATM Equity Program
Class of Stock [Line Items]
Maximum aggregate offering price	$ 250,000
Aggregate offering price of remaining common shares available for sale			$ 250,000
2013 ATM Equity Program
Class of Stock [Line Items]
Maximum aggregate offering price		$ 200,000
2015 Share Repurchase Program
Class of Stock [Line Items]
Maximum authorized amount for stock repurchases	$ 250,000

Earnings per Share (Details)

Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Numerator:
Income from continuing operations			$ 6,109	$ 3,328	$ 50,785	$ 8,875
Gain on sales of investment properties			66,385	75,001	97,737	113,214
Preferred stock dividends			(2,362)	(2,362)	(7,087)	(7,087)
Net income attributable to common shareholders			70,132	75,967	141,435	115,002
Distributions paid on unvested restricted shares			(108)	(130)	(348)	(340)
Net income attributable to common shareholders excluding amounts attributable to unvested restricted shares			$ 70,024	$ 75,837	$ 141,087	$ 114,662
Denominator for earnings per common share – basic:
Weighted average number of common shares outstanding			236,783	236,439	236,692	236,348
Effect of dilutive securities:
Stock options			2	2	2	2
RSUs			323	112	289	50
Denominator for earnings per common share – diluted:
Weighted average number of common and common equivalent shares outstanding			237,108	236,553	236,983	236,400
Earnings Per Share, Other Disclosures
Unvested restricted common stock	587	848	587	848	587	848
Weighted average number of shares of restricted common stock			596	818	657	760
Stock options
Antidilutive Securities Excluded from Computation of Earnings per Share [Line Items]
Number of outstanding options to purchase shares of common stock	41	53	41	53	41	53
Weighted average exercise price of outstanding options (in dollars per share)	$ 19.33	$ 19.39	$ 19.33	$ 19.39	$ 19.33	$ 19.39
Number of outstanding options to purchase shares of common stock that would be anti-dilutive	35	45
Weighted average exercise price of outstanding options excluded from diluted EPS calculation (in dollars per share)	$ 20.63	$ 20.74
RSUs
Earnings Per Share, Other Disclosures
Unvested restricted common stock	391		391		391		174
Antidilutive Securities Excluded from Computation of Earnings per Share [Line Items]
Number of RSUs eligible for future conversion	391	180	391	180	391	180
Weighted average number of RSUs			391	168	360	76

Provision for Impairment of I55

Provision for Impairment of Investment Properties (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016USD ($)ft²property	Sep. 30, 2015USD ($)ft²property	Sep. 30, 2016USD ($)ft²property	Sep. 30, 2015USD ($)ft²property
Impaired Long-Lived Assets Held and Used [Line Items]
Number of properties for which indicators of impairment were identified | property	5	3	5	3
Number of properties for which an impairment charge was recorded | property	1	0	1	0
Number of properties held for sale with impairment indicators but not impaired | property	1	0	1	0
Remaining properties for which indicators of impairment were identified but no impairment was considered necessary | property	3	3	3	3
Weighted average percentage by which projected undiscounted cash flows exceeded carrying value for each of the remaining properties	14.00%	39.00%	14.00%	39.00%
Number of properties with impairment indicators which were subsequently sold | property	2		2
Provision for impairment of investment properties	$ 4,742	$ 169	$ 11,048	$ 4,113
Estimated fair value of impaired properties as of impairment date			37,100	$ 20,970
South Billings Center
Impaired Long-Lived Assets Held and Used [Line Items]
Provision for impairment of investment properties			$ 2,164
Mid-Hudson Center
Impaired Long-Lived Assets Held and Used [Line Items]
Square footage | ft²	235,600		235,600
Provision for impairment of investment properties			$ 4,142
Saucon Valley Square
Impaired Long-Lived Assets Held and Used [Line Items]
Square footage | ft²	80,700		80,700
Provision for impairment of investment properties			$ 4,742
Massillon Commons
Impaired Long-Lived Assets Held and Used [Line Items]
Square footage | ft²		245,900		245,900
Provision for impairment of investment properties				$ 2,289
Traveler's Office Building
Impaired Long-Lived Assets Held and Used [Line Items]
Square footage | ft²		50,800		50,800
Provision for impairment of investment properties				$ 1,655
Shaw's Supermarket
Impaired Long-Lived Assets Held and Used [Line Items]
Square footage | ft²		65,700		65,700
Provision for impairment of investment properties				$ 169

Fair Value Measurements _ Fair

Fair Value Measurements – Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financial liabilities:
Mortgages payable, net	$ 1,000,089	$ 1,123,136
Unsecured notes payable, net	595,479	495,576
Unsecured term loans, net	447,302	447,526
Unsecured revolving line of credit	0	100,000
Carrying value
Financial assets:
Derivative asset	138	0
Financial liabilities:
Mortgages payable, net	1,000,089	1,123,136
Unsecured notes payable, net	595,479	495,576
Unsecured term loans, net	447,302	447,526
Unsecured revolving line of credit	0	100,000
Derivative liability	0	85
Fair value
Financial assets:
Derivative asset	138	0
Financial liabilities:
Mortgages payable, net	1,094,472	1,213,620
Unsecured notes payable, net	617,473	486,701
Unsecured term loans, net	450,000	450,000
Unsecured revolving line of credit	0	100,000
Derivative liability	$ 0	$ 85

Fair Value Measurements _ Recur

Fair Value Measurements – Recurring Fair Value Measurements (Details) - Recurring Fair Value Measurements - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value Measurements [Line Items]
Derivative asset	$ 138
Derivative liability		$ 85
Fair value, Level 2
Fair Value Measurements [Line Items]
Derivative asset	$ 138
Derivative liability		$ 85

Fair Value Measurements _ Nonre

Fair Value Measurements – Nonrecurring Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Fair Value Measurements [Line Items]
Provision for impairment		$ 4,742	$ 169	$ 11,048	$ 4,113
Nonrecurring Fair Value Measurements
Fair Value Measurements [Line Items]
Fair value of investment properties	$ 9,600	9,600		9,600
Provision for impairment				6,906
Fair value, Level 2 | Nonrecurring Fair Value Measurements
Fair Value Measurements [Line Items]
Fair value of investment properties	3,000	3,000		3,000
Fair value, Level 3 | Nonrecurring Fair Value Measurements
Fair Value Measurements [Line Items]
Fair value of investment properties	$ 6,600	$ 6,600		$ 6,600
Saucon Valley Square
Fair Value Measurements [Line Items]
Operating expense growth rate	3.10%
Discount rate	9.35%
Terminal capitalization rate	8.35%

Fair Value Measurements _ Fai59

Fair Value Measurements – Fair Value Disclosures (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Fair Value Measurements [Line Items]
Mortgages payable, net	$ 1,000,089	$ 1,123,136
Unsecured notes payable, net	595,479	495,576
Unsecured term loans, net	447,302	447,526
Unsecured revolving line of credit	0	100,000
Fair value, Level 1
Fair Value Measurements [Line Items]
Unsecured notes payable, net	249,908	239,482
Fair value, Level 3
Fair Value Measurements [Line Items]
Mortgages payable, net	1,094,472	1,213,620
Unsecured notes payable, net	367,565	247,219
Unsecured term loans, net	450,000	450,000
Unsecured revolving line of credit		100,000
Fair value, Total
Fair Value Measurements [Line Items]
Mortgages payable, net	1,094,472	1,213,620
Unsecured notes payable, net	617,473	486,701
Unsecured term loans, net	450,000	450,000
Unsecured revolving line of credit	$ 0	$ 100,000
Mortgages payable | Minimum
Fair Value Measurements [Line Items]
Discount rate (as a percent)	2.50%	2.20%
Mortgages payable | Maximum
Fair Value Measurements [Line Items]
Discount rate (as a percent)	3.80%	6.00%
Unsecured notes payable
Fair Value Measurements [Line Items]
Unsecured notes payable, net	$ 600,000	$ 500,000
Unsecured term loans | Weighted average
Fair Value Measurements [Line Items]
Discount rate (as a percent)	1.37%	1.30%
Unsecured revolving line of credit
Fair Value Measurements [Line Items]
Discount rate (as a percent)		1.35%
4.00% Notes Due 2025 | Unsecured notes payable
Fair Value Measurements [Line Items]
Unsecured notes payable, net	$ 250,000	$ 250,000
Stated interest rate (as a percent)	4.00%	4.00%
Notes Due 2021 and 2024 and Notes Due 2026 | Unsecured notes payable | Weighted average
Fair Value Measurements [Line Items]
Discount rate (as a percent)	3.61%
Notes Due 2021 and 2024 | Unsecured notes payable | Weighted average
Fair Value Measurements [Line Items]
Discount rate (as a percent)		4.64%

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016USD ($)property
Guarantees
Commitments and Contingencies [Line Items]
Amount of letters of credit outstanding	$ 143
Number of properties for which the Company has outstanding letters of credit | property	1
Reisterstown Road Plaza
Commitments and Contingencies [Line Items]
Number of properties with active redevelopment | property	1
Redevelopment costs incurred	$ 610
Reisterstown Road Plaza | Minimum
Commitments and Contingencies [Line Items]
Net estimated redevelopment costs	11,000
Reisterstown Road Plaza | Maximum
Commitments and Contingencies [Line Items]
Net estimated redevelopment costs	$ 12,000

Subsequent Events (Details)

Subsequent Events (Details)	Oct. 25, 2016$ / shares	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2016$ / shares	Sep. 30, 2015$ / shares	Oct. 24, 2016board_members
Subsequent Event [Line Items]
Preferred stock dividends declared (per share)				$ 1.3125	$ 1.3125
Common stock dividends declared (per share)				$ 0.496875	$ 0.496875
7.00% Series A cumulative redeemable preferred stock
Subsequent Event [Line Items]
Preferred stock, dividend rate		7.00%	7.00%
Subsequent events
Subsequent Event [Line Items]
Previous number of directors comprising the Board | board_members						8
Number of directors comprising the Board | board_members						9
Subsequent events | 7.00% Series A cumulative redeemable preferred stock
Subsequent Event [Line Items]
Preferred stock, dividend rate	7.00%
Preferred stock dividends declared (per share)	$ 0.4375
Subsequent events | Class A common stock
Subsequent Event [Line Items]
Common stock dividends declared (per share)	$ 0.165625