CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
REVENUES:
Rental income	$ 1,138,138	$ 1,035,105	$ 984,309
Joint venture management and other fees	$ 14,055	$ 11,754	$ 11,482
Type of revenue	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember	udr:ManagementAndOtherFeesMember
Total revenues	$ 1,152,193	$ 1,046,859	$ 995,791
OPERATING EXPENSES:
Property operating and maintenance	178,947	169,078	164,660
Real estate taxes and insurance	150,888	133,912	121,146
Property management	32,721	28,465	27,068
Other operating expenses	13,932	12,100	9,060
Real estate depreciation and amortization	501,257	429,006	430,054
General and administrative	51,533	46,983	48,566
Casualty-related charges/(recoveries), net	474	2,121	4,335
Other depreciation and amortization	6,666	6,673	6,408
Total operating expenses	936,418	828,338	811,297
Gain/(loss) on sale of real estate owned	5,282	136,197	43,404
Operating income	221,057	354,718	227,898
Income/(loss) from unconsolidated entities	137,873	(5,055)	31,257
Interest expense	(170,917)	(134,168)	(128,711)
Interest income and other income/(expense), net	15,404	6,735	1,971
Income/(loss) before income taxes	203,417	222,230	132,415
Tax (provision)/benefit, net	(3,838)	(688)	240
Net income/(loss)	199,579	221,542	132,655
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(14,426)	(18,215)	(10,933)
Net (income)/loss attributable to noncontrolling interests	(188)	(221)	(164)
Net income/(loss) attributable to UDR, Inc.	184,965	203,106	121,558
Distributions to preferred stockholders - Series E (Convertible)	(4,104)	(3,868)	(3,708)
Net income/(loss) attributable to common stockholders	$ 180,861	$ 199,238	$ 117,850
Income/(loss) per weighted average common share - basic	$ 0.63	$ 0.74	$ 0.44
Income/(loss) per weighted average common share - diluted	$ 0.63	$ 0.74	$ 0.44
Weighted average number of common shares outstanding - Basic	285,247	268,179	267,024
Weighted average number of common shares outstanding - diluted	286,015	269,483	268,830