Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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DERIVATIVES AND HEDGING ACTIVITY (UNITED DOMINION REALTY, L.P.) - Other Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships			$ 1
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	$ 1,700
Total amount of Interest expense presented on the Consolidated Statements of Operations	170,917	$ 134,168	128,711
United Dominion Realty L.P.
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships			100
Estimated additional accumulated other comprehensive Income/(Loss) transferred to interest expense	0
Fair value of operating partnerships derivative financial instruments	0	0
Total amount of Interest expense presented on the Consolidated Statements of Operations	1,639	8,733	18,156
Cash Flow Hedging \| Interest expense \| United Dominion Realty L.P.
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships	0
Interest rate contracts \| United Dominion Realty L.P.
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships	0	0
Interest rate contracts \| United Dominion Realty L.P. \| Maximum
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships			(100)
Interest rate contracts \| Other income/(expense)
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships	0	0
Interest rate contracts \| Other income/(expense) \| Maximum
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships			(100)
Interest rate contracts \| Other income/(expense) \| United Dominion Realty L.P.
Derivatives
Losses in the fair value of derivatives not designated in hedging relationships	$ 0	$ 0	$ 1