Reallocation of Credit Facilities Debt from General Partner

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- Definition

Secured debt including debt on real estate held for sale.

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No definition available.

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Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

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The average effective interest rate during the reporting period.

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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.

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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

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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

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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.

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No definition available.

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

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

+ References

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

+ References

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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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.

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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.

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Debt (UNITED DOMINION REALTY, L.P.) (Details Textual) - USD ($)			9 Months Ended	12 Months Ended
	Jun. 27, 2014	Sep. 26, 2013	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]
Amortization of Financing Costs				$ 7,000,000	$ 7,200,000
Borrowings outstanding				$ 2,300,000	1,900,000
Debt Instrument, Interest Rate During Period				3.74%
UDR Bank Credit Facility
Debt Instrument [Line Items]
Total revolving credit facility				$ 2,000,000,000	900,000,000
Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 952,801,000	963,713,000
Debt Instrument, Interest Rate During Period				4.93%
Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 424,144,000	390,608,000
Debt Instrument, Interest Rate During Period				1.53%
Fannie Mae
Debt Instrument [Line Items]
Borrowings outstanding				$ 813,840,000	834,282,000
Fannie Mae credit facilities \| Fixed Rate Debt
Debt Instrument [Line Items]
Debt, Weighted Average Interest Rate				5.23%
Debt Instrument, Maturity Date Range, Start				May 01, 2017
Debt Instrument, Maturity Date Range, End				Jul. 01, 2023
Fannie Mae credit facilities \| Variable Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate at Period End				1.71%
Mortgages [Member] \| Fixed Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				4.57%
Debt Instrument, Maturity Date Range, Start				Jun. 01, 2016
Debt Instrument, Maturity Date Range, End				Nov. 01, 2025
Notes payable minimum interest rates range				3.43%
Notes payable maximum interest rates range				6.16%
Mortgages [Member] \| Variable Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				2.19%
Tax-exempt secured notes payable \| Variable Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				0.75%
Unsecured Revolving Credit Facility due October 2015
Debt Instrument [Line Items]
Borrowings outstanding				$ 150,000,000	152,500,000
Debt Instrument, Interest Rate During Period				1.19%
Five Point Two Five Percent, Medium Term Notes, Due January 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				5.25%
4.25% Medium-Term Notes due June 2018
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				4.25%
Three point seven percent medium term note due October 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				3.70%
ThreePointSevenTermNotesDueOctober2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Maturity Date		Oct. 01, 2020
1.44% Term notes due January 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				1.44%
Debt Instrument, Maturity Date	Jan. 29, 2021
4.63% Medium-Term Notes due January 2022
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				4.63%
3.75 MTN Due July 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				3.75%
Debt Instrument, Maturity Date	Jul. 31, 2024
4.00% MTN Due October 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				4.00%
Debt Instrument, Maturity Date			Oct. 01, 2025
United Dominion Reality L.P.
Debt Instrument [Line Items]
Amortization of Financing Costs				$ 1,300,000	1,400,000
Secured Debt Including Debt on Real Estate Held for Sale				$ 475,964,000	927,484,000
Debt Instrument, Interest Rate During Period				3.76%
Reallocation of Credit Facilities Debt from General Partner				$ 17,557,000	0	$ 13,682,000
Unamortized fair market adjustment				0.0	6,200,000
United Dominion Reality L.P. \| Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 279,333,000	708,534,000
Debt Instrument, Interest Rate During Period				4.90%
United Dominion Reality L.P. \| Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 196,631,000	218,950,000
Debt Instrument, Interest Rate During Period				1.74%
United Dominion Reality L.P. \| Fannie Mae
Debt Instrument [Line Items]
Borrowings outstanding				$ 421,031,000	526,588,000
United Dominion Reality L.P. \| Fannie Mae credit facilities \| Fixed Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				5.08%
United Dominion Reality L.P. \| Fannie Mae credit facilities \| Variable Rate Debt
Debt Instrument [Line Items]
Debt Instrument, Interest Rate During Period				1.90%
United Dominion Reality L.P. \| Mortgages [Member] \| Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 30,132,000	378,371,000
Debt Instrument, Interest Rate During Period				3.43%
Notes payable minimum interest rates range				3.43%
United Dominion Reality L.P. \| Tax-exempt secured notes payable \| Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 27,000,000	27,000,000
Debt Instrument, Interest Rate During Period				0.76%
Debt Instrument, Maturity Date Range, End				Mar. 01, 2032
United Dominion Reality L.P. \| 2.90% Term Notes due January 2016 \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity				$ 250,000,000
United Dominion Reality L.P. \| 1.68% Term Notes due December 2016 \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity				$ 100,000,000
United Dominion Reality L.P. \| 4.25% Medium-Term Notes due June 2018
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End			Jun. 01, 2018
United Dominion Reality L.P. \| 4.25% Medium-Term Notes due June 2018 \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			$ 300,000,000
United Dominion Reality L.P. \| Three point seven percent medium term note due October 2020 [Member] \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			300,000,000
United Dominion Reality L.P. \| 1.44% Term notes due January 2021 [Member] \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			$ 350,000,000
United Dominion Reality L.P. \| 4.63% Medium-Term Notes due January 2022
Debt Instrument [Line Items]
Debt Instrument, Maturity Date Range, End			Jan. 01, 2022
United Dominion Reality L.P. \| 4.63% Medium-Term Notes due January 2022 \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			$ 400,000,000
United Dominion Reality L.P. \| 3.75 MTN Due July 2024 [Member] \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			300,000,000
United Dominion Reality L.P. \| 4.00% MTN Due October 2025 [Member] \| Financial Guarantee
Debt Instrument [Line Items]
Guarantor borrowing capacity			$ 300,000,000
Beginning of range of initial term of debt [Member] \| Fannie Mae credit facilities
Debt Instrument [Line Items]
Debt Instrument, Term				7 years
End of range of inital term of debt [Member] \| Fannie Mae credit facilities
Debt Instrument [Line Items]
Debt Instrument, Term				10 years
Fannie Mae credit facilities \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| Fannie Mae credit facilities \| Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 514,462,000	568,086,000
Fannie Mae credit facilities \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| Fannie Mae credit facilities \| Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				299,378,000	266,196,000
Fannie Mae credit facilities \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| United Dominion Reality L.P. \| Fannie Mae credit facilities \| Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				250,828,000	333,828,000
Fannie Mae credit facilities \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| United Dominion Reality L.P. \| Fannie Mae credit facilities \| Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				170,203,000	192,760,000
Mortgages [Member] \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| Mortgages [Member] \| Fixed Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				442,617,000	401,210,000
Mortgages [Member] \| Reported Value Measurement [Member] \| Fair Value, Measurements, Recurring [Member] \| Mortgages [Member] \| Variable Rate Debt
Debt Instrument [Line Items]
Secured Debt Including Debt on Real Estate Held for Sale				$ 31,337,000	$ 31,337,000