Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121549185&loc=d3e80748-113994

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

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Balance Type:	na
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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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Period Type:	instant

- Details

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- Details

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DERIVATIVES AND HEDGING ACTIVITY (UNITED DOMINION REALTY, L.P.) (Details) $ in Thousands	Sep. 30, 2020 USD ($) instrument	Dec. 31, 2019 instrument
Derivatives
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	$ 2,800
Not Designated as Hedging Instrument
Outstanding interest rate derivatives not designated as hedging instrument
Notional	0
United Dominion Realty L.P. \| Maximum
Derivatives
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	$ 100
United Dominion Realty L.P. \| Cash Flow Hedging
Outstanding interest rate derivatives not designated as hedging instrument
Number instruments \| instrument	1	0
United Dominion Realty L.P. \| Not Designated as Hedging Instrument
Outstanding interest rate derivatives not designated as hedging instrument
Number instruments \| instrument	0
United Dominion Realty L.P. \| Interest rate caps \| Cash Flow Hedging
Outstanding interest rate derivatives not designated as hedging instrument
Number instruments \| instrument	1
Notional	$ 19,880