Debt Instrument Facility Fee, Basis Spread on Variable Rate

No definition available.

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- Definition

Debt instrument weighted average years to maturity.

+ References

No definition available.

+ Details

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- Definition

Secured Debt, Encumbers Real Estate Owned, Amount.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Secured Debt, Encumbers Real Estate Owned, Percent.

+ References

No definition available.

+ Details

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- Definition

Secured Debt, Unencumbered Real Estate Owned, Amount.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Secured Debt, Unencumbered Real Estate Owned, Percent.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

+ Details

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- Details

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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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

+ Details

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Period Type:	instant

- Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(a))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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Period Type:	instant

- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ 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)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

-Article 5

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

-Publisher FASB

-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

+ Details

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Secured and Unsecured Debt (Details 2) (USD $)	9 Months Ended		9 Months Ended					9 Months Ended		9 Months Ended		9 Months Ended						3 Months Ended
Secured and Unsecured Debt (Details 2) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Fixed Rate Debt [Member]	Sep. 30, 2014 Variable Rate Debt [Member]	Sep. 30, 2014 ThreePointSevenTermNotesDueOctober2020 [Member]	Dec. 31, 2013 ThreePointSevenTermNotesDueOctober2020 [Member]	Sep. 30, 2013 ThreePointSevenTermNotesDueOctober2020 [Member]	Sep. 30, 2014 2.68% Term Notes due December 2016 [Member]	Dec. 31, 2013 2.68% Term Notes due December 2016 [Member]	Sep. 30, 2014 Four Point Six Three Percent Term Medium Notes Due January Two Thousand Twenty-Two [Member]	Dec. 31, 2013 Four Point Six Three Percent Term Medium Notes Due January Two Thousand Twenty-Two [Member]	Sep. 30, 2014 Mortgages Notes Payable [Member] Fixed Rate Debt [Member]	Sep. 30, 2014 Mortgages Notes Payable [Member] Variable Rate Debt [Member]	Sep. 30, 2014 Tax Exempt Notes Payable [Member] Variable Rate Debt [Member]	Sep. 30, 2014 Fannie Mae credit facilities [Member] Fixed Rate Debt [Member]	Sep. 30, 2014 Fannie Mae credit facilities [Member] Variable Rate Debt [Member]	Sep. 30, 2014 3.75 MTN Due July 2024 [Member]	Sep. 30, 2014 UDR Bank Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate																		1.10%
Debt Instrument Facility Fee, Basis Spread on Variable Rate																		0.20%
Secured Debt, Encumbers Real Estate Owned, Amount	$ 2,300,000,000
Secured Debt, Encumbers Real Estate Owned, Percent	26.90%
Debt Instrument Weighted Average Years to Maturity	4 years 6 months		3 years 2 months 29 days	6 years 2 months 17 days	6 years			3 years 8 months 4 days		7 years 3 months 10 days		1 year 9 months 3 days	2 years 3 months 25 days	8 years 5 months 8 days	4 years 3 months 7 days	5 years 9 months 7 days	9 years 9 months
Debt Instrument, Interest Rate, Stated Percentage						0.00%	3.70%	2.50%	2.68%	4.63%	4.63%						3.75%
Unamortized discount	8,000,000	11,800,000								2,792,000	2,882,000						1,000,000
Aggregate maturities of secured debt
2014	37,835,000
2015	521,233,000
2016	250,188,000
2017	402,955,000
2018	874,982,000
Thereafter	1,540,999,000
Total	1,399,372,000	1,442,077,000
Secured Debt, Unencumbered Real Estate Owned, Amount	$ 6,100,000,000
Secured Debt, Unencumbered Real Estate Owned, Percent	73.10%