2.4.0.82406402 - Disclosure - Real Estate Owned (UNITED DOMINION REALTY, L.P.) (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$I2013Q2http://www.sec.gov/CIK0000074208instant2013-06-30T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$I2012Q4http://www.sec.gov/CIK0000074208instant2012-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4udr_SummaryOfCarryingAmountsForRealEstateOwnedAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Summary of carrying amounts for real estate owned (at cost)2false 5us-gaap_LandAndLandImprovementsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse12650490001265049USD$falsetruefalse2truefalsefalse19071690001907169USD$falsetruefalsexbrli:monetaryItemTypemonetaryCarrying amount of real estate held for productive use and alterations to land which improves its potential for use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6812-107765 false2Land3true 5udr_DepreciablePropertyHeldAndUsedAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Depreciable property - held and used:4false 6us-gaap_InvestmentBuildingAndBuildingImprovementsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse60549330006054933USD$falsefalsefalse2truefalsefalse53849710005384971USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(d)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 false2Building and improvements5false 6us-gaap_FurnitureAndFixturesGrossus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse262999000262999USD$falsefalsefalse2truefalsefalse272640000272640USD$falsefalsefalsexbrli:monetaryItemTypemonetaryGross amount, at the balance sheet date, of long-lived, depreciable assets commonly used in offices and stores. Examples include desks, chairs, and store fixtures.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 false2Furniture, fixtures and equipment6true 5udr_RealEstateUnderDevelopmentAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Under development:7false 6us-gaap_DevelopmentInProcessus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse432461000432461USD$falsefalsefalse2truefalsefalse489795000489795USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe current amount of expenditures for a real estate project that has not yet been completed.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 false2Under development8false 5udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse80166880008016688USD$falsefalsefalse2truefalsefalse80558280008055828USD$falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.true2Real estate owned9false 5us-gaap_RealEstateAccumulatedDepreciationus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-2071649000-2071649USD$falsefalsefalse2truefalsefalse-1924682000-1924682USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount as of the balance sheet date of accumulated depreciation pertaining to real estate properties.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule III -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 28 -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28.FN4) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 false2Accumulated depreciation10false 5udr_RealEstateNetudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse59450390005945039USD$falsefalsefalse2truefalsefalse61311460006131146USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe net book value of real estate held for investment and real estate under 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6us-gaap_DevelopmentInProcessus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse112091000112091USD$falsefalsefalse2truefalsefalse151154000151154USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe current amount of expenditures for a real estate project that has not yet been completed.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 false2Under development14false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse5false USDtruefalse$I2013Q2_us-gaap_PropertyPlantAndEquipmentByTypeAxis_us-gaap_ConstructionInProgressMemberhttp://www.sec.gov/CIK0000074208instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseConstruction in progress 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Examples include desks, chairs, and store fixtures.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 5 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229 false2Furniture, fixtures and equipment23true 5udr_RealEstateUnderDevelopmentAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Under development:24false 6us-gaap_DevelopmentInProcessus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse118449000118449USD$falsefalsefalse2truefalsefalse8626000086260USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe current amount of expenditures for a real estate project that has not yet been completed.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.10) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 false2Under development25false 5udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse42626450004262645USD$falsefalsefalse2truefalsefalse41829200004182920USD$falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.true2Real estate owned26false 5us-gaap_RealEstateAccumulatedDepreciationus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-1187753000-1187753USD$falsefalsefalse2truefalsefalse-1097133000-1097133USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount as of the balance sheet date of accumulated depreciation pertaining to real estate properties.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph c -Subparagraph Schedule III -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 28 -Article 12 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 10 -Section S99 -Paragraph 6 -Subparagraph (SX 210.5-04.(c) Schedule III) -URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 970 -SubTopic 360 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-28.FN4) -URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024 false2Accumulated depreciation27false 5udr_RealEstateNetudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse30748920003074892USD$falsefalsefalse2truefalsefalse30857870003085787USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe net book value of real estate held for investment and real estate under development.No definition available.true2Total real estate owned, net of accumulated depreciation28false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse9false USDtruefalse$I2013Q2_dei_LegalEntityAxis_udr_UnitedDominionRealityLPMember_us-gaap_PropertyPlantAndEquipmentByTypeAxis_us-gaap_LandMemberhttp://www.sec.gov/CIK0000074208instant2013-06-30T00:00:000001-01-01T00:00:00falsefalseUnited Dominion Reality L.P. 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