Consolidated Statement of Partners' Capital and Comprehensive/(Loss) (UNITED DOMINION REALTY, L.P) (Unaudited) (USD $) In Thousands	Total	Accumulated Other Comprehensive Income/(Loss)	United Dominion Reality.L.P [Member]	United Dominion Reality.L.P [Member] Class A Limited Partner [Member]	United Dominion Reality.L.P [Member] Limited Partners [Member]	United Dominion Reality.L.P [Member] Limited Partner [Member]	United Dominion Reality.L.P [Member] General Partner [Member]	United Dominion Reality.L.P [Member] Accumulated Other Comprehensive Income/(Loss)	United Dominion Reality.L.P [Member] Total Partner's Capital [Member]	United Dominion Reality.L.P [Member] Receivable Due From General Partner [Member]	United Dominion Reality.L.P [Member] Non-controlling interest
Beginning Balance at Dec. 31, 2010			$ 1,561,623	$ 41,199	$ 77,858	$ 1,927,323	$ 1,363	$ (5,502)	$ 2,042,241	$ (492,709)	$ 12,091
Distributions			(70,302)	(1,164)	(1,788)	(67,308)	(42)		(70,302)
OP Unit Redemptions for common shares of UDR					(46)	46
OP Units issued for real estate	62,878		62,878		62,878				62,878
Adjustment to reflect limited partners' capital at redemption value				2,917	5,228	(8,145)
Other comprehensive income/loss:
Unrealized loss from derivative financial instruments	(3,553)	(3,553)	(457)					(457)	(457)
Net income			5,504	52	175	5,215	3		5,445		59
Total comprehensive income			5,047	52	175	5,215	3	(457)	4,988		59
Net change in receivable due from General Partner			58,143							58,143
Ending Balance at Jun. 30, 2011			$ 1,617,389	$ 43,004	$ 144,305	$ 1,857,131	$ 1,324	$ (5,959)	$ 2,039,805	$ (434,566)	$ 12,150

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Net of tax effect change in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges after taxes. A cash flow hedge is a hedge of the exposure to variability in the cash flows of a recognized asset or liability or a forecasted transaction that is attributable to a particular risk. The change includes an entity's share of an equity investee's increase or decrease in deferred hedging gains or losses. While for technical reasons this element has no balance attribute, the default assumption is a credit balance consistent with its label.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

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Total of Partners' Capital (deficit) items including portions attributable to both the parent and noncontrolling interests (previously referred to as minority interest), if any. The entity including portions attributable to the parent and noncontrolling interests is sometimes referred to as the economic entity. This excludes temporary equity and is sometimes called permanent equity.

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