[Line Items] for Consolidation and Basis of Presentation [Table]

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- Definition

General Partners Capital Account Units Owned Percentage.

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- Definition

Limited Partners Capital Account Units Outstanding Percentage.

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- Definition

Number Of Apartment Homes Owned And Consolidated By Company

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- Definition

Number of Markets Operating Within

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- Definition

Rental Revenues, Percent of Parent Revenue

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- Definition

The number of general partner units outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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- Definition

The number of limited partner units outstanding.

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- Definition

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

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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04.16(a))
-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996

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-URI http://asc.fasb.org/extlink&oid=120401414&loc=d3e603758-122996

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-Name Accounting Standards Codification
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-Paragraph 5
-Subparagraph (SAB TOPIC 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

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CONSOLIDATION AND BASIS OF PRESENTATION - GP Units (UNITED DOMINION REALTY, L.P.) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020 community item shares	Sep. 30, 2019	Sep. 30, 2020 community item shares	Sep. 30, 2019	Dec. 31, 2019 shares
Basis of presentation
Number of real estate properties \| community	148		148
Number of apartments owned (in apartments homes) \| item	47,488		47,488
Operating Partnership outstanding units	184.8		184.8
Operating Partnership units outstanding related to limited partner	184,836,000		184,836,000		184,064,000
United Dominion Realty L.P.
Basis of presentation
Rental revenues percent of General Partner's consolidated rental revenues	35.00%	39.00%	35.00%	40.00%
General Partners' ownership (as a percent)	95.30%		95.30%
OP units outstanding related to general partner	100,000		100,000
Operating Partnership units outstanding related to limited partner	176.2		176.2
United Dominion Realty L.P.
Basis of presentation
Number of real estate properties \| community	52		52
Number of markets operating within (in markets) \| item	15		15
Number of apartments owned (in apartments homes) \| item	16,434		16,434
Operating Partnership outstanding units	184,800,000		184,800,000		184,100,000
OP units outstanding related to general partner	110,883		110,883		110,883
Operating Partnership units outstanding related to limited partner	184,724,677		184,724,677		183,952,659
UDR, Inc.
Basis of presentation
General Partners' ownership (as a percent)	57.60%		57.60%
Operating Partnership outstanding units	18.7		18.7
Operating Partnership units outstanding related to limited partner	176,100,000		176,100,000		176,100,000
Percentage of units outstanding in Partnership	95.30%		95.30%		95.70%
UDR, Inc. \| United Dominion Realty L.P.
Basis of presentation
General Partners' ownership (as a percent)	95.30%		95.30%
Operating Partnership outstanding units					176,200,000
OP units outstanding related to general partner	176.2		176.2
Percentage of units outstanding in Partnership					95.70%
Non-affiliated Partners
Basis of presentation
Operating Partnership outstanding units	13.7		13.7
Operating Partnership units outstanding related to limited partner	8.6		8.6
Percentage of units outstanding in Partnership	4.70%		4.70%
Non-affiliated Partners \| United Dominion Realty L.P.
Basis of presentation
Operating Partnership outstanding units					7.9
Operating Partnership units outstanding related to limited partner	8.6		8.6
Percentage of units outstanding in Partnership	4.70%		4.70%		4.30%
Class A Limited Partner \| United Dominion Realty L.P.
Basis of presentation
Operating Partnership units outstanding related to limited partner	1,900,000		1,900,000		1,900,000
Class A Limited Partner \| UDR, Inc.
Basis of presentation
Operating Partnership units outstanding related to limited partner	100,000		100,000		100,000
Non-affiliated Partners \| United Dominion Realty L.P.
Basis of presentation
Operating Partnership units outstanding related to limited partner	8,600,000		8,600,000		7,900,000
Percentage of units outstanding in Partnership	4.70%		4.70%		4.30%
Non-affiliated Partners \| Class A Limited Partner
Basis of presentation
Operating Partnership units outstanding related to limited partner	1,752,000		1,752,000		1,752,000