Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 52,088us-gaap_Revenues	$ 52,947us-gaap_Revenues
Expenses	(13,763)us-gaap_CostOfRealEstateRevenue	(13,241)us-gaap_CostOfRealEstateRevenue
Income from real estate	38,325us-gaap_GrossProfit	39,706us-gaap_GrossProfit
Interest expense and amortization of deferred debt costs	(11,406)	(11,467)
General and administrative	(3,771)us-gaap_GeneralAndAdministrativeExpense	(4,680)us-gaap_GeneralAndAdministrativeExpense
Acquisition related costs	(21)	(163)
Predevelopment expenses		(503)us-gaap_OtherOperatingIncomeExpenseNet
Subtotal	23,127	22,893
Depreciation and amortization of deferred leasing costs	(10,440)	(10,180)
Change in fair value of derivatives	(6)	(2)
Net Income	12,681us-gaap_ProfitLoss	12,711us-gaap_ProfitLoss
Capital investment	10,624	13,888
Total assets	1,270,611us-gaap_Assets	1,204,597us-gaap_Assets	1,266,987us-gaap_Assets
Shopping Centers
Segment Reporting Information [Line Items]
Revenue	39,364	39,819
Expenses	(9,536)	(9,490)
Income from real estate	29,828	30,329
Interest expense and amortization of deferred debt costs	0	0
General and administrative	0	0
Acquisition related costs	(21)	(163)
Predevelopment expenses		0
Subtotal	29,807	30,166
Depreciation and amortization of deferred leasing costs	(7,316)	(6,897)
Change in fair value of derivatives	0	0
Net Income	22,491	23,269
Capital investment	2,946	10,732
Total assets	937,619	895,510
Mixed-Use Properties
Segment Reporting Information [Line Items]
Revenue	12,711	13,113
Expenses	(4,227)	(3,751)
Income from real estate	8,484	9,362
Interest expense and amortization of deferred debt costs	0	0
General and administrative	0	0
Acquisition related costs	0	0
Predevelopment expenses		(503)
Subtotal	8,484	8,859
Depreciation and amortization of deferred leasing costs	(3,124)	(3,283)
Change in fair value of derivatives	0	0
Net Income	5,360	5,576
Capital investment	7,678	3,156
Total assets	312,311	293,919
Corporate and Other
Segment Reporting Information [Line Items]
Revenue	13	15
Expenses	0	0
Income from real estate	13	15
Interest expense and amortization of deferred debt costs	(11,406)	(11,467)
General and administrative	(3,771)	(4,680)
Acquisition related costs	0	0
Predevelopment expenses		0
Subtotal	(15,164)	(16,132)
Depreciation and amortization of deferred leasing costs	0	0
Change in fair value of derivatives	(6)	(2)
Net Income	(15,170)	(16,134)
Capital investment	0	0
Total assets	$ 20,681	$ 15,168

Depreciation, Depletion and Amortization, Including Discontinued Operations

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Noncash Interest Expense Accretion And Amortization Of Deferred Finance Fees

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- Definition

Segment Reporting Information, Operating Income (Loss) before Depreciation and Amortization

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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- Definition

This element represents the total of the costs related to real estate revenues, including management, leasing, and development services.

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-Name Accounting Standards Codification

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The net amount of other operating income and expenses, the components of which are not separately disclosed on the income statement, from items that are associated with the entity's normal revenue producing operations.

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- Definition

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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