The amount of advances to notes payable.

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Long Term Incentive Plan Operating Partnership Unit Grants, Value

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Net change in amount due to/(from) General Partner.

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The amount of operating partnership unit redemptions for common shares of parent company.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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Total change in each class of partners' capital accounts during the year due to redemptions and adjustments to redemption value. All partners include general, limited and preferred partners.

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Amount of partners' capital (deficit), including portions attributable to both the parent and noncontrolling interests. Excludes temporary equity and is sometimes called permanent equity.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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CONSOLIDATED STATEMENT OF CHANGES IN CAPITAL (UNITED DOMINION REALTY, L.P.) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income/(loss)	$ 89,615	$ 89,225	$ 75,627	$ 28,396	$ 221,542	$ 132,655	$ 320,380
United Dominion Reality L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		1,875,130		1,618,499	1,875,130	1,618,499	1,721,330
Net income/(loss)	86,324	91,845	61,546	14,007	231,485	107,855	79,262
Distributions					(237,827)	(228,090)	(216,763)
Long Term Incentive Plan Unit grants					15,839	7,763	3,735
Unrealized gain/(loss) on derivative financial investments						107	6
Conversion of Advances (to)/from the General Partner to notes payable					(257,204)
Net change in advances (to)/from the General Partner					(141,534)	368,996	30,929
Ending Balance	1,485,889		1,875,130		1,485,889	1,875,130	1,618,499
United Dominion Reality L.P. \| Advances (to)/from General Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		397,899		19,659	397,899	19,659	(11,270)
Conversion of Advances (to)/from the General Partner to notes payable					(257,204)
Net change in advances (to)/from the General Partner					(140,695)	378,240	30,929
Ending Balance			397,899			397,899	19,659
United Dominion Reality L.P. \| Accumulated Other Comprehensive Income/(Loss), net
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance				(113)		(113)	(113)
Unrealized gain/(loss) on derivative financial investments						113
Ending Balance							(113)
United Dominion Reality L.P. \| Total Partner's Capital
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		1,464,295		1,578,202	1,464,295	1,578,202	1,713,412
Net income/(loss)					229,763	106,307	77,818
Distributions					(237,827)	(228,090)	(216,763)
Long Term Incentive Plan Unit grants					15,839	7,763	3,735
Unrealized gain/(loss) on derivative financial investments						113
Ending Balance	1,472,070		1,464,295		1,472,070	1,464,295	1,578,202
United Dominion Reality L.P. \| Noncontrolling Interests
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		12,936		20,638	12,936	20,638	19,188
Net income/(loss)					1,722	1,548	1,444
Unrealized gain/(loss) on derivative financial investments						(6)	6
Net change in advances (to)/from the General Partner					(839)	(9,244)
Ending Balance	13,819		12,936		13,819	12,936	20,638
United Dominion Reality L.P. \| Class A Limited Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		67,474		63,901	67,474	63,901	64,409
Net income/(loss)					2,221	1,015	743
Distributions					(2,328)	(2,328)	(2,328)
Adjustment to reflect limited partners’ capital at redemption value					2,034	4,886	1,077
Ending Balance	69,401		67,474		69,401	67,474	63,901
United Dominion Reality L.P. \| Limited Partners and LTIP Units
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		283,568		269,928	283,568	269,928	268,481
Net income/(loss)					9,977	4,270	3,099
Distributions					(10,718)	(9,704)	(8,831)
OP Unit redemptions for common shares of UDR					(416)	(288)	(175)
Adjustment to reflect limited partners’ capital at redemption value					4,295	11,599	3,619
Long Term Incentive Plan Unit grants					15,839	7,763	3,735
Ending Balance	302,545		283,568		302,545	283,568	269,928
United Dominion Reality L.P. \| Limited Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		1,112,298		1,243,460	1,112,298	1,243,460	1,379,525
Net income/(loss)					217,426	100,957	73,928
Distributions					(224,637)	(215,922)	(205,472)
OP Unit redemptions for common shares of UDR					416	288	175
Adjustment to reflect limited partners’ capital at redemption value					(6,329)	(16,485)	(4,696)
Ending Balance	1,099,174		1,112,298		1,099,174	1,112,298	1,243,460
United Dominion Reality L.P. \| General Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Beginning Balance		$ 955		$ 1,026	955	1,026	1,110
Net income/(loss)					139	65	48
Distributions					(144)	(136)	(132)
Ending Balance	$ 950		$ 955		$ 950	$ 955	$ 1,026