Discontinued Operations (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended
May 31, 2011	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Apr. 05, 2011
Summary of income from discontinued operations
Rental income		$ 451	$ 7,274	$ 7,258	$ 14,578
Non-property income				1	1,849
Total Income		451	7,274	7,259	16,427
Rental expenses		161	2,169	2,367	4,511
Property management fee		12	200	199	401
Real estate depreciation		54	3,472	2,651	6,940
Interest		64	769	817	1,540
Total Expenses		291	6,610	6,034	13,392
Income before net gain on the sale of depreciable property		160	664	1,225	3,035
Net gain on the sale of depreciable property		44,658	197	44,699	156
Income from discontinued operations		44,818	861	45,924	3,191
Discontinued Operations (Textuals)
Gain on sale of community for financial reporting purposes		$ 44,658	$ 197	$ 44,699	$ 156
Homes sold under multifamily communities						1,418
Home sold under apartment community	289
Units of community sold			149		149

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Disposal group including discontinued operation income.

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Disposal group including discontinued operation interest.

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Disposal group including discontinued operation non property income.

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The aggregate total of property management fee expense that is attributable to the disposal group.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives that is attributable to the disposal group. Includes production and non-production related depreciation.

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The aggregate total of rental expenses that is attributable to the disposal group.

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Home sold under apartment community.

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Homes sold under multifamily communities.

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Summary of income from discontinued operations.

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Total amount of apartment homes sold during the period.

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Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group.

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Amount of operating expenses attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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