Other Comprehensive Income/(Loss) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Other comprehensive income/loss:
Net income/(loss) attributable to UDR, Inc	$ 14,651	$ (26,621)	$ (13,224)	$ (50,677)
Gain on marketable securities reclassified to earnings			(3,492)
Unrealized loss from derivative financial instruments	(6,835)	(1,604)	(3,553)	(2,838)
Allocation to redeemable non-controlling interests	246	82	229	135
Comprehensive income/(loss)	$ 8,099	$ (28,778)	$ (19,952)	$ (54,204)

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

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.

+ References

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+ Details

- Definition

Reclassification adjustment for unrealized gains or losses realized upon the sale of securities, after tax.

+ References

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+ Details