Discontinued Operations (Details) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Discontinued operations
Rental revenue	$ 33,672	$ 29,222	$ 98,377	$ 84,855
Rental operating expenses	(9,328)	(8,714)	(26,823)	(23,998)
Real estate taxes and insurance	(5,020)	(4,636)	(15,007)	(13,646)
Depreciation and amortization	(12,389)	(9,655)	(35,239)	(26,600)
Net income		1,161	556	3,470
Discontinued operations
Discontinued operations
Rental revenue		2,147	689	6,573
Rental operating expenses		(23)	(5)	(70)
Real estate taxes and insurance		(204)	(56)	(757)
Depreciation and amortization		(759)	(72)	(2,276)
Net income		$ 1,161	$ 556	$ 3,470

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

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate revenue from real estate operations during the reporting period.

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The aggregate total of real estate taxes and insurance expense.

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