INCOME/(LOSS) PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jul. 31, 2021
Numerator for income/(loss) per share:
Net income/(loss)	$ 403,715	$ 95,877	$ 474,488
Net (income)/loss attributable to redeemable noncontrolling interests in the Operating Partnership and DownREIT Partnership	(25,965)	(6,246)	(30,104)
Net (income)/loss attributable to noncontrolling interests	(46)	(46)	(31)
Net income/(loss) attributable to UDR, Inc.	377,704	89,585	444,353
Distributions to preferred stockholders - Series E (Convertible)	(4,839)	(4,835)	(4,848)
Net income/(loss) attributable to common stockholders	372,865	84,750	439,505
Income/(loss) attributable to common stockholders - diluted	$ 372,865	$ 84,750	$ 439,505
Denominator for income/(loss) per share:
Weighted average common shares outstanding	330,833,000	329,670,000	329,136,000
Unvested restricted stock awards	(511,000)	(380,000)	(371,000)
Denominator for basic income/(loss) per share	330,322,000	329,290,000	328,765,000
Incremental shares issuable from assumed conversion of unvested LTIP Units, performance units, stock options and unvested restricted stock	731,000	826,000	339,000
Denominator for diluted income/(loss) per share	331,053,000	330,116,000	329,104,000
Income/(loss) per weighted average common share - basic	$ 1.13	$ 0.26	$ 1.34
Income/(loss) per weighted average common share - diluted	$ 1.13	$ 0.26	$ 1.34
Number of shares authorized	450,000,000	450,000,000
Number of shares agreed to repurchase (in shares)	3,300,000
Average price of shares repurchased (dollar per share)	$ 36.12
Repurchase of common shares	$ 117,811		$ 25,009
OP/DownREIT Units
Denominator for income/(loss) per share:
Antidilutive securities	22,817,000	23,993,000	22,410,000
Convertible preferred stock
Denominator for income/(loss) per share:
Antidilutive securities	2,816,000	2,848,000	2,908,000
Unvested LTIP Units, performance units, stock options, and unvested restricted stock
Denominator for income/(loss) per share:
Antidilutive securities	731,000	826,000	339,000
ATM
Denominator for income/(loss) per share:
Number of shares authorized				20,000,000
Shares of common stock available for future issuance	14,000,000