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'Monetary' elements on report '2410409 - Disclosure - Secured and Unsecured Debt (Details Textual 1)' had a mix of different decimal attribute values. 'Shares' elements on report '2413402 - Disclosure - Earnings/(Loss) Per Share (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2416402 - Disclosure - Noncontrolling Interests (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2417405 - Disclosure - Debt (UNITED DOMINION REALTY, L.P.) (Details Textual)' had a mix of different decimal attribute values. 'Monetary' elements on report '2418401 - Disclosure - Related Party Transactions (UNITED DOMINION REALTY, L.P.) (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2421404 - Disclosure - Derivatives and Hedging Activity (Details 2)' had a mix of different decimal attribute values. 'Monetary' elements on report '2421406 - Disclosure - Derivatives and Hedging Activity (Details Textual)' had a mix of different decimal attribute values. 'Monetary' elements on report '2422404 - Disclosure - Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details 2)' had a mix of different decimal attribute values. 'Monetary' elements on report '2422406 - Disclosure - Derivatives and Hedging Activity (UNITED DOMINION REALTY, L.P.) (Details Textual)' had a mix of different decimal attribute values. 'Monetary' elements on report '2427402 - Disclosure - Reportable Segments (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2428402 - Disclosure - Reportable Segments (UNITED DOMINION REALTY, L.P.) (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '2430401 - Disclosure - Hurricane Related (Recoveries)/Charges (UNITED DOMINION REALTY, L.P.) (Details)' had a mix of different decimal attribute values. Process Flow-Through: 1001000 - Statement - Consolidated Balance Sheets Process Flow-Through: Removing column 'Jun. 30, 2012' Process Flow-Through: Removing column 'Dec. 31, 2011' Process Flow-Through: 1001501 - Statement - Consolidated Balance Sheets (Parenthetical) Process Flow-Through: 1002000 - Statement - Consolidated Balance Sheets (UNITED DOMINION REALTY, L.P) Process Flow-Through: Removing column 'Jun. 30, 2012' Process Flow-Through: Removing column 'Dec. 31, 2011' Process Flow-Through: 1002501 - Statement - Consolidated Balance Sheets (UNITED DOMINION REALTY, L.P) (Parenthetical) Process Flow-Through: 1003000 - Statement - Consolidated Statements of Operations (Unaudited) Process Flow-Through: Removing column '3 Months Ended Mar. 31, 2012' Process Flow-Through: Removing column '12 Months Ended Dec. 31, 2010' Process Flow-Through: 1004000 - Statement - Consolidated Statements of Operations (UNITED DOMINION REALTY, L.P) Process Flow-Through: Removing column '12 Months Ended Dec. 31, 2010' Process Flow-Through: 1005000 - Statement - Consolidated Statements of Comprehensive Income / (Loss) Process Flow-Through: 1006000 - Statement - Consolidated Statements of Comprehensive Income / Loss (UNITED DOMINION REALTY, L.P.) Process Flow-Through: 1007501 - Statement - Consolidated Statements of Changes in Equity (Unaudited) (Parenthetical) Process Flow-Through: Removing column '3 Months Ended Jun. 30, 2013' Process Flow-Through: Removing column '3 Months Ended Jun. 30, 2012' Process Flow-Through: Removing column '6 Months Ended Jun. 30, 2012' Process Flow-Through: 1008000 - Statement - Consolidated Statements of Changes in Capital (UNITED DOMINION REALTY, L.P) (Unaudited) Process Flow-Through: Removing column '3 Months Ended Jun. 30, 2012' Process Flow-Through: Removing column '6 Months Ended Jun. 30, 2012' Process Flow-Through: 1009000 - Statement - Consolidated Statements of Cash Flows (Unaudited) Process Flow-Through: Removing column '12 Months Ended Dec. 31, 2010' Process Flow-Through: 1009501 - Statement - Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) Process Flow-Through: 1010000 - Statement - Consolidated Statements of Cash Flows (UNITED DOMINION REALTY, L.P) (Unaudited) udr-20130630.xml udr-20130630.xsd udr-20130630_cal.xml udr-20130630_def.xml udr-20130630_lab.xml udr-20130630_pre.xml true true