Limited Partners' Capital Account, Required Period To Be Outstanding Before Unit is Redeemable

No definition available.

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- Definition

Cumulative, annual, non-compounded preferred return percentage of Class A Partnership units.

+ References

No definition available.

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- Definition

Limited Partners Capital Account Units Outstanding Percentage.

+ References

No definition available.

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- Definition

Limited Partners' Capital Account, Units Redeemed

+ References

No definition available.

+ Details

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- Definition

Limited Partners' Capital Account, Unit Value1

+ References

No definition available.

+ Details

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- Definition

The value of OP Units issued as [noncash or part noncash] consideration for a business or asset acquired. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

No definition available.

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- Definition

The number of general partner units outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-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=27012166&loc=d3e187171-122770

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

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- Definition

The number of limited partner units outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 272

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70434-108055

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-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=27012166&loc=d3e187171-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 4

-Section F

+ Details

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- Definition

As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of common shares (regardless of class), limited partnership units (regardless of class), non-preferential membership interests, or any other form of common equity regardless of investee entity legal form.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 14

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (16)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 15

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (12)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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- Details

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- Details

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- Details

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Capital Structure (UNITED DOMINION REALTY, L.P.) (Details Textual) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed	(1,002,556)
Limited partnership units owned	183,278,698	183,278,698	184,281,254	184,281,254
Redeemable non-controlling interests in operating partnership	$ 217,597	$ 282,480
United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
General Partners' Capital Account, Units Outstanding	110,883	110,883
Limited partnership units owned	183,167,815	183,167,815
Required period to be outstanding before unit is redeemable		1 year
Redeemable non-controlling interests in operating partnership	217,597	282,480
OP Units issued for real estate		77,041	0
UDR, Inc.
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	173,848,891	174,002,342
Percentage of units	94.90%	95.00%
Non-affiliated Partners
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	9,318,924	9,165,473
Percentage of units	5.10%	5.00%
Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned		1,751,671
Cumulative, annual, non-compounded preferred return on Class A Partnership units		8.00%
Value of Class A Partnership units (in dollars per share)		$ 16.61
Class A Limited Partner \| United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	1,751,671	1,873,332
Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	7,567,253	7,413,802	7,643,548	7,669,632
Limited Partner \| United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
OP Units issued for real estate			(133)
Limited Partner \| UDR, Inc.
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, Units Redeemed	1,002,556
Limited partnership units owned	173,848,891	174,002,342	174,775,152	174,749,068
Limited Partner \| Class A Limited Partner
Limited Partners' Capital Account [Line Items]
Limited partnership units owned	1,751,671	1,751,671	1,751,671	1,751,671
Partnership Capital [Member] \| United Dominion Reality L.P.
Limited Partners' Capital Account [Line Items]
OP Units issued for real estate	$ 23,329		$ 0