Consolidated Statements of Comprehensive Income / (Loss) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income/(loss)	$ 159,842us-gaap_ProfitLoss	$ 46,282us-gaap_ProfitLoss	$ 220,303us-gaap_ProfitLoss
Other comprehensive income/(loss) - derivative instruments:
Unrealized holding gain/(loss)loss	(8,695)	(469)	(4,924)
(Gain)/loss reclassified into earnings from other comprehensive income/(loss)	4,834	6,851	7,649
Other comprehensive income/(loss), including portion attributable to noncontrolling interests	(3,861)	6,382	2,725
Comprehensive income/(loss)	155,981	52,664	223,028
Comprehensive (income)/loss attributable to noncontrolling interests	(5,375)	(1,720)	(8,206)
Comprehensive income/(loss) attributable to UDR, Inc.	$ 150,606us-gaap_ComprehensiveIncomeNetOfTax	$ 50,944us-gaap_ComprehensiveIncomeNetOfTax	$ 214,822us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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