CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Preferred Stock	Common Stock	Paid-in Capital	Distributions in Excess of Net Income	Accumulated Other Comprehensive Income/(Loss), net	Noncontrolling Interests	Total
Beginning Balance at Dec. 31, 2015	$ 46,458	$ 2,618	$ 4,447,816	$ (1,584,459)	$ (12,678)	$ 856	$ 2,900,611
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				292,718			292,718
Net income/(loss) attributable to noncontrolling interests						322	322
Disposition of noncontrolling interest of consolidated real estate						(1,155)	(1,155)
Contribution of noncontrolling interests in consolidated real estate						102	102
Long Term Incentive Plan Unit grants/(vestings), net						3,735	3,735
Other comprehensive income/(loss)					7,069		7,069
Issuance/(forfeiture) of common and restricted shares, net		2	4,973				4,975
Issuance of common shares through public offering		50	173,161				173,211
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		3	9,463				9,466
Common stock distributions declared ($1.29, $1.24, $1.18 per share for the years ended December 31, 2018, 2017, and 2016 respectively)				(315,102)			(315,102)
Preferred stock distributions declared-Series E ($1.3968, $1.3288, $1.3288 per share for the year ended December 31, 2018, 2017, and 2016 respectively)				(3,717)			(3,717)
Adjustment to reflect redemption value of redeemable noncontrolling interests				24,735			24,735
Ending Balance at Dec. 31, 2016	46,458	2,673	4,635,413	(1,585,825)	(5,609)	3,860	3,096,970
Consolidated Statements of Changes in Equity
Net income/(loss) attributable to UDR, Inc.				121,558			121,558
Net income/(loss) attributable to noncontrolling interests						147	147
Contribution of noncontrolling interests in consolidated real estate						125	125
Long Term Incentive Plan Unit grants/(vestings), net						5,432	5,432
Other comprehensive income/(loss)					2,928		2,928
Issuance/(forfeiture) of common and restricted shares, net		1	437				438
Conversion of Series E Cumulative Convertible Shares	(257)		257
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		4	14,540				14,544
Common stock distributions declared ($1.29, $1.24, $1.18 per share for the years ended December 31, 2018, 2017, and 2016 respectively)				(331,974)			(331,974)
Preferred stock distributions declared-Series E ($1.3968, $1.3288, $1.3288 per share for the year ended December 31, 2018, 2017, and 2016 respectively)				(3,708)			(3,708)
Adjustment to reflect redemption value of redeemable noncontrolling interests				(71,096)			(71,096)
Ending Balance at Dec. 31, 2017	46,201	2,678	4,651,205	(1,871,603)	(2,681)	9,564	2,835,364
Consolidated Statements of Changes in Equity
Cumulative effect upon adoption of ASU 2016-09			558	(558)
Net income/(loss) attributable to UDR, Inc.				203,106			203,106
Net income/(loss) attributable to noncontrolling interests						175	175
Contribution of noncontrolling interests in consolidated real estate						108	108
Repurchase of common shares		(6)	(19,982)				(19,988)
Long Term Incentive Plan Unit grants/(vestings), net						7,305	7,305
Other comprehensive income/(loss)					2,614		2,614
Exercise of stock options, net		8	(23,061)				(23,053)
Issuance/(forfeiture) of common and restricted shares, net		(1)	(507)				(508)
Issuance of common shares through public offering		72	299,753				299,825
Adjustment for conversion of noncontrolling interest of unitholders in the Operating Partnership and DownREIT Partnership		4	13,324				13,328
Common stock distributions declared ($1.29, $1.24, $1.18 per share for the years ended December 31, 2018, 2017, and 2016 respectively)				(348,079)			(348,079)
Preferred stock distributions declared-Series E ($1.3968, $1.3288, $1.3288 per share for the year ended December 31, 2018, 2017, and 2016 respectively)				(3,868)			(3,868)
Adjustment to reflect redemption value of redeemable noncontrolling interests				(43,552)			(43,552)
Ending Balance at Dec. 31, 2018	$ 46,201	$ 2,755	$ 4,920,732	$ (2,063,996)	$ (67)	$ 17,152	$ 2,922,777