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Cumulative Adjustment to Net Income Attributable to Noncontrolling Interest

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- Definition

Development Costs Excluding Direct Costs and Capitlized Interest

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- Definition

Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 35

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848

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- Definition

Amount of interest capitalized, including amount of allowance for funds used during construction.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

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-Topic 980

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-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6501662&loc=d3e56162-110433

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Significant Accounting Policies (UNITED DOMINION REALTY, L.P.) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting Policies [Line Items]
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company			0.10
Development costs excluding direct costs and capitalized interest	$ 8,953,000	$ 11,100,000	$ 10,000,000
Interest capitalized during period	20,200,000	29,400,000	26,400,000
Advertising expense	6,000,000us-gaap_AdvertisingExpense	5,700,000us-gaap_AdvertisingExpense	6,200,000us-gaap_AdvertisingExpense
Minimum \| Buildings
Accounting Policies [Line Items]
Estimated useful lives	35 years
Minimum \| Building improvements
Accounting Policies [Line Items]
Estimated useful lives	10 years
Minimum \| Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	3 years
Maximum \| Buildings
Accounting Policies [Line Items]
Estimated useful lives	55 years
Maximum \| Building improvements
Accounting Policies [Line Items]
Estimated useful lives	35 years
Maximum \| Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	10 years
United Dominion Reality L.P.
Accounting Policies [Line Items]
Cumulative Adjustment to Net Income Attributable to Noncontrolling Interest		3,300,000
Minimum Percentage of Carrying Value Of Real Estate Portfolio Held By Company	0.10
Development costs excluding direct costs and capitalized interest	2,010,000	2,500,000	2,100,000
Interest capitalized during period	2,900,000	5,900,000	3,700,000
Advertising expense	$ 2,500,000	$ 2,500,000	$ 2,400,000
United Dominion Reality L.P. \| Minimum \| Buildings
Accounting Policies [Line Items]
Estimated useful lives	35 years
United Dominion Reality L.P. \| Minimum \| Building improvements
Accounting Policies [Line Items]
Estimated useful lives	10 years
United Dominion Reality L.P. \| Minimum \| Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	3 years
United Dominion Reality L.P. \| Maximum \| Buildings
Accounting Policies [Line Items]
Estimated useful lives	55 years
United Dominion Reality L.P. \| Maximum \| Building improvements
Accounting Policies [Line Items]
Estimated useful lives	35 years
United Dominion Reality L.P. \| Maximum \| Furniture, fixtures, equipment, and other assets
Accounting Policies [Line Items]
Estimated useful lives	10 years