Extension period of option on loan

No definition available.

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- Definition

Increment in unsecured revolving credit facility under certain circumstances.

+ References

No definition available.

+ Details

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- Definition

Secured Debt, Encumbers Real Estate Owned, Amount.

+ References

No definition available.

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- Definition

Secured Debt, Encumbers Real Estate Owned, Percent.

+ References

No definition available.

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- Definition

Secured debt including debt on real estate held for sale.

+ References

No definition available.

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- Definition

Secured Debt, Unencumbered Real Estate Owned, Amount.

+ References

No definition available.

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- Definition

Secured Debt, Unencumbered Real Estate Owned, Percent.

+ References

No definition available.

+ Details

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- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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- Definition

The average effective interest rate during the reporting period.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

When presenting a range of interest rates, the highest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

When presenting a range of interest rates, the lowest effective rate for funds borrowed under the debt agreement as of the balance sheet date.

+ References

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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+ Details

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- Definition

Latest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Name Accounting Standards Codification

-Topic 210

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-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(2))

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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.16)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Period Type:	instant

- Definition

Description of the fees for amounts available, but unused under the credit facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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- Definition

Description of the interest rate for the amounts borrowed under the credit facility, including the terms and the method for determining the interest rate (for example, fixed or variable, LIBOR plus a percentage, increasing rate, timing of interest rate resets, remarketing provisions).

+ References

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Secured and Unsecured Debt (Details Textual) (USD $)	3 Months Ended	0 Months Ended	3 Months Ended
Secured and Unsecured Debt (Details Textual) (USD $)	Mar. 31, 2015	Jun. 27, 2014	Mar. 31, 2014	Dec. 31, 2014
Secured Debt (Textual) [Abstract]
Secured debt amount which encumbers real estate owned based upon book value	$ 2,300,000,000
Percentage of secured debt which encumbers real estate owned based upon book value	26.70%
Secured debt amount of real estate owned which is unencumbered	6,200,000,000
Percentage of secured debt of real estate owned which is unencumbered	73.30%
Weighted average interest rate	3.62%
Unamortized fair market adjustment	7,000,000			6,700,000
Borrowings outstanding	1,500,000us-gaap_LineOfCredit			1,900,000us-gaap_LineOfCredit
Extension period of option on loan	6 months
Line of Credit Facility, Interest Rate Description	100
Line of Credit Facility, Commitment Fee Description	15
Fixed Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	978,440,000			969,296,000
Weighted average interest rate	5.28%
Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	392,233,000			392,233,000
Weighted average interest rate	1.44126%
3.75 MTN Due July 2024 [Member]
Secured Debt (Textual) [Abstract]
Weighted average interest rate	3.75%
Unamortized fair market adjustment	964,000			990,000
Debt Instrument, Maturity Date		Jul. 01, 2024
Mortgages Notes Payable [Member] \| Fixed Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Weighted average interest rate	5.49%
Debt Instrument, Maturity Date Range, Start	Dec. 09, 2015
Debt instrument, maturity date range, end	May 01, 2019
Notes payable minimum interest rates range	3.43%
Notes payable maximum interest rates range	6.16%
Mortgages Notes Payable [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Weighted average interest rate	1.94%
Debt Assumed As Part of Acquisition [Member]
Secured Debt (Textual) [Abstract]
Amortization of Debt Discount (Premium)	1,100,000		1,300,000
Tax Exempt Notes Payable [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Weighted average interest rate	0.76%
Fannie Mae credit facilities [Member] \| Fixed Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Debt, Weighted Average Interest Rate	5.12%
Debt Instrument, Maturity Date Range, Start	May 01, 2017
Debt instrument, maturity date range, end	Jul. 01, 2023
Fannie Mae credit facilities [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Debt Instrument, Interest Rate at Period End	1.62%
Tax Exempt Secured Notes Payable [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Debt Instrument, Maturity Date Range, Start	Aug. 01, 2019
Debt instrument, maturity date range, end	Mar. 20, 2032
Notes payable minimum interest rates range	0.76%
Notes payable maximum interest rates range	0.77%
Fannie Mae [Member]
Secured Debt (Textual) [Abstract]
Borrowings outstanding	833,365,000			834,282,000
1.67% Term Notes due December 2016 [Member]
Secured Debt (Textual) [Abstract]
Weighted average interest rate	1.32%
Debt Instrument, Maturity Date	Jun. 01, 2018
UDR Bank Credit Facility [Member]
Secured Debt (Textual) [Abstract]
Credit facilities with aggregate commitment	900,000,000			900,000,000
Increment in Unsecured Revolving Credit Facility Under Certain Circumstances	1,450,000,000
Line of Credit [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member] \| Fannie Mae credit facilities [Member] \| Fixed Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	567,169,000			568,086,000
Line of Credit [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member] \| Fannie Mae credit facilities [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	266,196,000			266,196,000
Mortgages Notes Payable [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member] \| Mortgages Notes Payable [Member] \| Fixed Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	411,271,000			401,210,000
Mortgages Notes Payable [Member] \| Carrying (Reported) Amount, Fair Value Disclosure [Member] \| Fair Value, Measurements, Recurring [Member] \| Mortgages Notes Payable [Member] \| Variable Rate Debt [Member]
Secured Debt (Textual) [Abstract]
Secured debt including debt on real estate held for sale	$ 31,337,000			$ 31,337,000