Amount of amortization expense attributable to debt issuance costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unsecured short-term debt instrument issued by corporations which are highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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- Definition

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

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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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- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 210
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-Paragraph 1
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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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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term unsecured obligations issued by corporations and other borrowers to investors (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02.19,20,22)
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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DEBT, NET (UNITED DOMINION REALTY, L.P.) - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Oct. 26, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fixed and variable rate debt
Amortization of financing costs		$ 1,100	$ 1,100	$ 3,200	$ 3,200
Long-term commercial paper		500,000		500,000
Borrowings outstanding at end of period		3,300		3,300		$ 3,300
Unsecured Commercial Bank Credit Facility
Fixed and variable rate debt
Total revolving credit facility		2,000,000		2,000,000
Commercial Paper
Fixed and variable rate debt
Commercial paper program		415,000		415,000		300,000
Term Loan due September 2023 \| Unsecured Commercial Bank Credit Facility
Fixed and variable rate debt
Total revolving credit facility		350,000		350,000
Term note due January 2029 \| Unsecured Commercial Bank Credit Facility
Fixed and variable rate debt
Total revolving credit facility	$ 300,000
Interest rate	4.40%
United Dominion Reality L.P.
Fixed and variable rate debt
Amortization of financing costs				100	$ 300
Borrowings outstanding at end of period		133,205		133,205		133,205
United Dominion Reality L.P. \| Financial Guarantee
Fixed and variable rate debt
Guarantor borrowing capacity		1,100,000		1,100,000
United Dominion Reality L.P. \| Maximum
Fixed and variable rate debt
Amortization of financing costs		100	$ 100
United Dominion Reality L.P. \| Unsecured Commercial Bank Credit Facility
Fixed and variable rate debt
Long-term commercial paper		500,000		500,000
United Dominion Reality L.P. \| Fannie Mae credit facilities
Fixed and variable rate debt
Borrowings outstanding at end of period		133,200		133,200
United Dominion Reality L.P. \| Unsecured Commercial Paper
Fixed and variable rate debt
Borrowings outstanding at end of period		415,000		415,000		$ 300,000
United Dominion Reality L.P. \| 3.70% Term Notes Due October 2020
Fixed and variable rate debt
Guarantor borrowing capacity		300,000		300,000
United Dominion Reality L.P. \| 4.63% Medium-Term Notes due January 2022
Fixed and variable rate debt
Guarantor borrowing capacity		400,000		400,000
United Dominion Reality L.P. \| Term Loan due September 2023
Fixed and variable rate debt
Guarantor borrowing capacity		350,000		350,000
United Dominion Reality L.P. \| 3.75% Medium-Term Notes Due July 2024
Fixed and variable rate debt
Guarantor borrowing capacity		300,000		300,000
United Dominion Reality L.P. \| 4.00% Medium-Term Note due October 2025
Fixed and variable rate debt
Guarantor borrowing capacity		300,000		300,000
United Dominion Reality L.P. \| 2.95% Medium-Term Note due September 2026
Fixed and variable rate debt
Guarantor borrowing capacity		300,000		300,000
United Dominion Reality L.P. \| 3.50 Medium-Term Note due July 2027
Fixed and variable rate debt
Guarantor borrowing capacity		$ 300,000		$ 300,000
United Dominion Reality L.P. \| Term note due January 2029 \| Unsecured Commercial Bank Credit Facility \| Financial Guarantee
Fixed and variable rate debt
Guarantor borrowing capacity	$ 300,000
Interest rate	4.40%
Fannie Mae credit facilities \| Fixed Rate Debt
Fixed and variable rate debt
Repayments of outstanding borrowing	$ 195,800