CONSOLIDATION AND BASIS OF PRESENTATION (Details) shares in Millions	12 Months Ended
Dec. 31, 2025 community home item shares	Dec. 31, 2024 shares
Consolidation And Basis Of Presentation
Number of real estate properties \| community	165
Number of apartment homes owned and consolidated \| home	55,240
Number of markets operating within \| item	21
Joint venture, number of completed or to be completed homes in communities \| home	12,167
Preferred equity investment,, number of apartment homes \| home	6,766
Operating partnership outstanding units	190.1	189.8
United Dominion Reality L.P.
Consolidation And Basis Of Presentation
General Partners' ownership (as a percent)	92.90%	93.00%
General partnership units outstanding	176.6	176.6
UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
General Partners' ownership (as a percent)	71.90%	71.00%
General partnership units outstanding	23.3	23.0
UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating partnership outstanding units	32.4	32.4
Non-affiliated Partners \| United Dominion Reality L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner	13.5	13.2
Percentage of units outstanding in Partnership	7.10%	7.00%
Non-affiliated Partners \| UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner	9.1	9.4
Percentage of units outstanding in Partnership	28.10%	29.00%

Consolidation and basis of presentation.

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General Partners Capital Account Units Owned Percentage.

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Represent element information joint venture number of completed or to be completed apartment homes in operating communities.

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Limited Partners Capital Account Units Outstanding Percentage.

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Number Of Apartment Homes Owned And Consolidated By Company

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Represents the number of apartment homes with ownership interest through preferred equity investments.

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Number of Markets Operating Within

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The number of general partner units outstanding.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-5

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The number of limited partner units outstanding.

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The number of real estate properties owned as of the balance sheet date.

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The number of each class of partnership units outstanding at the balance sheet date. Units represent shares of ownership of the general, limited, and preferred partners.

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