BASIS OF PRESENTATION (Details) shares in Millions	1 Months Ended	6 Months Ended
Jul. 31, 2026 item	Jun. 30, 2026 home community item shares
Consolidation And Basis Of Presentation
Number of real estate properties \| community		162
Number of apartment homes owned and consolidated \| home		54,173
Number of markets operating within \| item		21
Joint venture, number of completed or to be completed homes in communities \| home		8,720
Preferred equity investment,, number of apartment homes \| home		3,319
Operating partnership outstanding units		190.5
Subsequent Event
Consolidation And Basis Of Presentation
Number of units exchanges for new classes of units \| item	2
United Dominion Reality L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner		177.2
General Partners' ownership (as a percent)		93.00%
General partnership units outstanding		0.1
UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating partnership outstanding units		23.7
General Partners' ownership (as a percent)		73.10%
UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating partnership outstanding units		32.4
Non-affiliated Partners \| United Dominion Reality L.P.
Consolidation And Basis Of Presentation
Operating Partnership units outstanding related to limited partner		13.3
Percentage of units outstanding in Partnership		7.00%
Non-affiliated Partners \| UDR Lighthouse DownREIT L.P.
Consolidation And Basis Of Presentation
Operating partnership outstanding units		8.7
Percentage of units outstanding in Partnership		26.90%

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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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Number of new classes of units exchanged

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The number of general partner units outstanding.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480100/505-10-S45-8

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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 275
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482861/275-10-50-2

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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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