2.4.0.82428402 - Disclosure - Reportable Segments (UNITED DOMINION REALTY, L.P.) 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All considered to be "operating revenue" for purposes of the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a),(b),(c) -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a, b, c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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. false2Reportable apartment home segment rental income3false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse128653000128653000USD$falsefalsefalse2truefalsefalse128911000128911000USD$falsefalsefalse3truefalsefalse253969000253969000USD$falsefalsefalse4truefalsefalse257025000257025000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI4true 5udr_ReconciliationItemToConsolidatedAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reconciling items:5false 6udr_SegmentReportingReconcilingItemsOwnedPropertyManagementCostsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-5187000-5187000USD$falsefalsefalse2truefalsefalse-5244000-5244000USD$falsefalsefalse3truefalsefalse-10255000-10255000USD$falsefalsefalse4truefalsefalse-10451000-10451000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe aggregate costs related to management of owned properties and discontinued operations during the reporting period.No definition available.false2Property management6false 6udr_OtherCostAndExpenseOperatingIncludingDiscontinuedOperationsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-1807000-1807000USD$falsefalsefalse2truefalsefalse-1434000-1434000USD$falsefalsefalse3truefalsefalse-3450000-3450000USD$falsefalsefalse4truefalsefalse-2817000-2817000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryOther Cost And Expense Operating Including Discontinued OperationsNo definition available.false2Other operating expenses7false 6udr_SegmentReportingReconcilingItemsCostOfServicesDepreciationAndAmortizationudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-85131000-85131000USD$falsefalsefalse2truefalsefalse-84474000-84474000USD$falsefalsefalse3truefalsefalse-168573000-168573000USD$falsefalsefalse4truefalsefalse-178721000-178721000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDepreciation of property, plant and equipment directly related to services rendered to owned properties and discontinued operations by an entity during the reporting period.No definition available.false2Depreciation and amortization8false 6udr_OtherGeneralAndAdministrativeExpenseIncludingDiscontinuedOperationsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-9866000-9866000USD$falsefalsefalse2truefalsefalse-13738000-13738000USD$falsefalsefalse3truefalsefalse-19342000-19342000USD$falsefalsefalse4truefalsefalse-23117000-23117000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryOther General And Administrative Expense Including Discontinued OperationsNo definition available.false2General and administrative9false 6us-gaap_InsuranceRecoveriesus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse27720002772000USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalse3truefalsefalse57930005793000USD$falsefalsefalse4truefalsefalse00USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 false2Hurricane-related (recoveries)/charges, net10false 6udr_SegmentReportingReconcilingItemsGainLossOnSaleOfPropertyudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse172006000172006000USD$falsefalsefalse3truefalsefalse00USD$falsefalsefalse4truefalsefalse252531000252531000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryGain on sale of depreciable property, including RE3 gains, net of tax.No definition available.false2Net gain on sale of depreciable property11false 6us-gaap_MinorityInterestInNetIncomeLossOtherMinorityInterestsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-3000-3000USD$falsefalsefalse2truefalsefalse-43000-43000USD$falsefalsefalse3truefalsefalse-7000-7000USD$falsefalsefalse4truefalsefalse-95000-95000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of net income or loss for the period allocated to noncontrolling shareholders, unit holders, partners, or other equity holders in one or more of the entities consolidated into the reporting entity's financial statements other than those noncontrolling interests already defined within the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. true2Net (loss)/income attributable to Entity13true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:14false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse80166880008016688000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse80166880008016688000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse80558280008055828000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets15false 6udr_RealEstatesOwnedAccumulatedDepreciationudr_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-2071649000-2071649000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse-2071649000-2071649000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse-1924682000-1924682000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAccumulated depreciation for real estate owned, including real estate held for investment, real estate under development, and real estate held for disposition.No definition available.false2Accumulated depreciation16false 6udr_RealEstateNetudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse59450390005945039000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse59450390005945039000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse61311460006131146000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net book value of real estate held for investment and real estate under development.No definition available.false2Total real estate owned, net of accumulated depreciation17true 6us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reconciling items:18false 7us-gaap_CashAndCashEquivalentsAtCarryingValueus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse90350009035000USD$falsefalsefalse2truefalsefalse184112000184112000USD$falsefalsefalse3truefalsefalse90350009035000USD$falsefalsefalse4truefalsefalse184112000184112000USD$falsefalsefalse5truefalsefalse1211500012115000USD$falsefalsefalse6truefalsefalse1250300012503000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of currency on hand as well as demand deposits with banks or financial institutions. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Cash and cash equivalents19false 7us-gaap_OtherRestrictedAssetsus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse2484300024843000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse2484300024843000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse2356100023561000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal assets that cannot be used for operating purposes because of contract or regulatory requirements that are in effect for a period that extends beyond one year.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 false2Restricted cash20false 7us-gaap_DeferredFinanceCostsNetus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse2704300027043000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse2704300027043000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse2499000024990000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryFor an unclassified balance sheet, the carrying amount (net of accumulated amortization) as of the balance sheet date of capitalized costs associated with the issuance of debt instruments (for example, legal, accounting, underwriting, printing, and registration costs) that will be charged against earnings over the life of the debt instruments to which such costs pertain.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.No definition available.false256Number of reportable segments25false 5udr_ConditionForCommunityConsideredToHaveStabilizedOccupancyudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse0090% occupancy for at least three consecutive monthsfalsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringCondition for Community considered to have stabilized occupancy.No definition available.false0Condition for Community considered to have stabilized occupancy26false 5udr_CommunityThresholdPercentOccupancyThresholdudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3truetruefalse0.90.9falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsenum:percentItemTypepureCommunity Threshold, Percent Occupancy ThresholdNo definition available.false0Percent occupancy to be considered a community27false 5udr_CommunityThresholdPeriodAboveOccupancyThresholdudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse003 monthsfalsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:durationItemTypenaCommunity Threshold, Period Above Occupancy ThresholdNo definition available.false0Time to maintain percent occupancy to be considered a community28false 5udr_TenantOrRelatedGroupOfTenantsContributedTenPercentOrMoreOfCompanyRevenueudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse00falsefalsefalse2truefalsefalse00falsefalsefalse3truefalsefalse00falsefalsefalse4truefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:integerItemTypeintegerTenant or related group of tenants contributed 10% or more of company total revenue.No definition available.false0Number of Tenants or related group of tenants that contributed 10% or more of company total revenue29true 4udr_ReportableSegmentsAdditionalTextualAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable Segments Additional (Textual) [Abstract]30false 5us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1480000014800000USD$falsefalsefalse2truefalsefalse1570000015700000USD$falsefalsefalse3truefalsefalse2170000021700000USD$falsefalsefalse4truefalsefalse2560000025600000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reportable apartment home segment rental income34false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse4344800043448000USD$falsefalsefalse2truefalsefalse4043500040435000USD$falsefalsefalse3truefalsefalse8531100085311000USD$falsefalsefalse4truefalsefalse7966300079663000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI35true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:36false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse24123800002412380000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse24123800002412380000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse24229870002422987000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets37false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse12false USDtruefalse$D2013Q2_us-gaap_StatementBusinessSegmentsAxis_udr_SameCommunitiesMidAtlanticRegionMemberhttp://www.sec.gov/CIK0000074208duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSame Store Communities Mid-Atlantic Region [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiudr_SameCommunitiesMidAtlanticRegionMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Same Store Communities Mid-Atlantic Region [Member]38true 4udr_SummaryOfRentalIncomeAndNoiForReportableSegmentsAndReconciliationOfNoiToLossFromContinuingOperationsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations39false 5us-gaap_SegmentReportingInformationRevenueus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse4160000041600000USD$falsefalsefalse2truefalsefalse4043600040436000USD$falsefalsefalse3truefalsefalse8295000082950000USD$falsefalsefalse4truefalsefalse8016200080162000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reportable apartment home segment rental income46false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1069900010699000USD$falsefalsefalse2truefalsefalse97250009725000USD$falsefalsefalse3truefalsefalse2077000020770000USD$falsefalsefalse4truefalsefalse1902600019026000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI47true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:48false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse730427000730427000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse730427000730427000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse723437000723437000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets49false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse22false USDtruefalse$D2013Q2_us-gaap_StatementBusinessSegmentsAxis_udr_SameCommunitiesSoutheasternRegionMemberhttp://www.sec.gov/CIK0000074208duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSame Store Communities Southeastern Region [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiudr_SameCommunitiesSoutheasternRegionMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Same Store Communities Southeastern Region [Member]50true 4udr_SummaryOfRentalIncomeAndNoiForReportableSegmentsAndReconciliationOfNoiToLossFromContinuingOperationsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations51false 5us-gaap_SegmentReportingInformationRevenueus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse2893400028934000USD$falsefalsefalse2truefalsefalse2736400027364000USD$falsefalsefalse3truefalsefalse5747800057478000USD$falsefalsefalse4truefalsefalse5437600054376000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reportable apartment home segment rental income52false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1881200018812000USD$falsefalsefalse2truefalsefalse1776400017764000USD$falsefalsefalse3truefalsefalse3751600037516000USD$falsefalsefalse4truefalsefalse3535600035356000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI53true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:54false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse880537000880537000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse880537000880537000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse887482000887482000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets55false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalse27false USDtruefalse$D2013Q2_us-gaap_StatementBusinessSegmentsAxis_udr_SameCommunitiesSouthwesternRegionMemberhttp://www.sec.gov/CIK0000074208duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseSame Store Communities Southwestern Region [Member]us-gaap_StatementBusinessSegmentsAxisxbrldihttp://xbrl.org/2006/xbrldiudr_SameCommunitiesSouthwesternRegionMemberus-gaap_StatementBusinessSegmentsAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Same Store Communities Southwestern Region [Member]56true 4udr_SummaryOfRentalIncomeAndNoiForReportableSegmentsAndReconciliationOfNoiToLossFromContinuingOperationsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Summary of rental income and NOI for UDRs reportable segments and reconciliation of NOI to loss from continuing operations57false 5us-gaap_SegmentReportingInformationRevenueus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1116200011162000USD$falsefalsefalse2truefalsefalse1047200010472000USD$falsefalsefalse3truefalsefalse2216800022168000USD$falsefalsefalse4truefalsefalse2063900020639000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of total revenue for the reportable segments, including revenue from external customers, transactions with other operating segments of the same entity, and (gross) interest revenue. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reportable apartment home segment rental income64false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse1967900019679000USD$falsefalsefalse2truefalsefalse2690500026905000USD$falsefalsefalse3truefalsefalse3889400038894000USD$falsefalsefalse4truefalsefalse5516100055161000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI65true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:66false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse21814000002181400000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse21814000002181400000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse22166720002216672000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets67true 4udr_ReportableSegmentsAdditionalTextualAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable Segments Additional (Textual) [Abstract]68false 5us-gaap_AdditionsToNoncurrentAssetsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse13235021323502USD$falsefalsefalse2truefalsefalse16000001600000USD$falsefalsefalse3truefalsefalse16459621645962USD$falsefalsefalse4truefalsefalse40000004000000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryTotal expenditures for additions to long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets of the reportable segment; if the amount: (a) is included in the determination of segment assets reviewed by the chief operating decision maker or (b) is otherwise regularly provided to the chief operating decision maker, even if not included in the determination of segment assets.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 28 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reportable apartment home segment rental income74false 5udr_SegmentReportingInformationNetOperatingIncomeudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse7246100072461000USD$falsefalsefalse2truefalsefalse7115000071150000USD$falsefalsefalse3truefalsefalse142584000142584000USD$falsefalsefalse4truefalsefalse140688000140688000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRental income less total rental expenses, which includes real estate taxes and insurance, personnel, utilities, repair and maintenance, and administrative and marketing expenses for reportable segments.No definition available.false2Reportable apartment home segment NOI75true 5udr_ReconciliationItemToConsolidatedAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reconciling items:76false 6udr_SegmentReportingReconcilingItemsOwnedPropertyManagementCostsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-2824000-2824000USD$falsefalsefalse2truefalsefalse-2789000-2789000USD$falsefalsefalse3truefalsefalse-5576000-5576000USD$falsefalsefalse4truefalsefalse-5519000-5519000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe aggregate costs related to management of owned properties and discontinued operations during the reporting period.No definition available.false2Property management77false 6udr_OtherCostAndExpenseOperatingIncludingDiscontinuedOperationsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-1423000-1423000USD$falsefalsefalse2truefalsefalse-1305000-1305000USD$falsefalsefalse3truefalsefalse-2809000-2809000USD$falsefalsefalse4truefalsefalse-2623000-2623000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryOther Cost And Expense Operating Including Discontinued OperationsNo definition available.false2Other operating expenses78false 6udr_SegmentReportingReconcilingItemsCostOfServicesDepreciationAndAmortizationudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-45307000-45307000USD$falsefalsefalse2truefalsefalse-46733000-46733000USD$falsefalsefalse3truefalsefalse-90700000-90700000USD$falsefalsefalse4truefalsefalse-98410000-98410000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryDepreciation of property, plant and equipment directly related to services rendered to owned properties and discontinued operations by an entity during the reporting period.No definition available.false2Depreciation and amortization79false 6udr_SegmentReportingReconcilingItemsInterestIncomeExpenseNetudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse-9050000-9050000USD$falsefalsefalse2truefalsefalse-12891000-12891000USD$falsefalsefalse3truefalsefalse-18312000-18312000USD$falsefalsefalse4truefalsefalse-25861000-25861000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRepresents the portion of interest incurred in the period on debt arrangements that was charged against earnings, including that of discontinued operations.No definition available.false2Interest80false 6udr_OtherGeneralAndAdministrativeExpenseIncludingDiscontinuedOperationsudr_falsedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-5894000-5894000USD$falsefalsefalse2truefalsefalse-7295000-7295000USD$falsefalsefalse3truefalsefalse-11469000-11469000USD$falsefalsefalse4truefalsefalse-14946000-14946000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryOther General And Administrative Expense Including Discontinued OperationsNo definition available.false2General and administrative81false 6us-gaap_InsuranceRecoveriesus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse22570002257000USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalse3truefalsefalse42760004276000USD$falsefalsefalse4truefalsefalse00USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe amount recovered from insurance. These recoveries reduce costs and losses that are reported as a separate line item under operating expenses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.3) -URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688 false2Hurricane-related (recoveries)/charges, net82false 6udr_SegmentReportingReconcilingItemsGainLossOnSaleOfPropertyudr_falsecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse5126600051266000USD$falsefalsefalse3truefalsefalse00USD$falsefalsefalse4truefalsefalse5118200051182000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryGain on sale of depreciable property, including RE3 gains, net of tax.No definition available.false2Net gain on sale of depreciable property83false 6us-gaap_MinorityInterestInNetIncomeLossOtherMinorityInterestsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse-66000-66000USD$falsefalsefalse2truefalsefalse-231000-231000USD$falsefalsefalse3truefalsefalse-112000-112000USD$falsefalsefalse4truefalsefalse-265000-265000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of net income or loss for the period allocated to noncontrolling shareholders, unit holders, partners, or other equity holders in one or more of the entities consolidated into the reporting entity's financial statements other than those noncontrolling interests already defined within the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Non-controlling interests84false 6us-gaap_NetIncomeLossus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse1015400010154000USD$falsefalsefalse2truefalsefalse5117200051172000USD$falsefalsefalse3truefalsefalse1788200017882000USD$falsefalsefalse4truefalsefalse4424600044246000USD$falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe portion of profit or loss for the period, net of income taxes, which is attributable to the parent.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28, 29, 30 -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. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=20435746&loc=d3e565-108580 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 19 -Article 5 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Other Comprehensive Income -URI http://asc.fasb.org/extlink&oid=6519514 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Net Income -URI http://asc.fasb.org/extlink&oid=6518256 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 51 -Paragraph 38 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. true2Net (loss)/income attributable to Entity85true 5udr_ReportableApartmentHomeSegmentAssetsAbstractudr_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reportable apartment home segment assets:86false 6udr_RealEstateOwnedGrossudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse42626450004262645000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse42626450004262645000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse41829200004182920000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryReal Estate Owned Gross.No definition available.false2Total segment assets87false 6udr_RealEstatesOwnedAccumulatedDepreciationudr_falsecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-1187753000-1187753000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse-1187753000-1187753000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse-1097133000-1097133000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAccumulated depreciation for real estate owned, including real estate held for investment, real estate under development, and real estate held for disposition.No definition available.false2Accumulated depreciation88false 6udr_RealEstateNetudr_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse30748920003074892000USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse30748920003074892000USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse30857870003085787000USD$falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net book value of real estate held for investment and real estate under development.No definition available.false2Total real estate owned, net of accumulated depreciation89true 6us-gaap_ReconciliationFromSegmentTotalsToConsolidatedAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Reconciling items:90false 7us-gaap_CashAndCashEquivalentsAtCarryingValueus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse31970003197000USD$falsefalsefalse2truefalsefalse11740001174000USD$falsefalsefalse3truefalsefalse31970003197000USD$falsefalsefalse4truefalsefalse11740001174000USD$falsefalsefalse5truefalsefalse28040002804000USD$falsefalsefalse6truefalsefalse704000704000USD$falsefalsefalsexbrli:monetaryItemTypemonetaryAmount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. 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All considered to be "operating revenue" for purposes of the taxonomy.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a),(b),(c) -URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e8736-108599 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 131 -Paragraph 27 -Subparagraph a, b, c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Capital expenditures related to segmentsfalseReportable Segments (UNITED DOMINION REALTY, L.P.) (Details) (USD $)NoRoundingUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.udr.com/role/ReportableSegmentsUnitedDominionRealtyLPDetails6138