XML 26 R1.htm IDEA: XBRL DOCUMENT v3.3.1.900
Document and Entity Information - USD ($)
$ in Billions
 12 Months Ended
Dec. 31, 2015
Feb. 22, 2016
Entity Information [Line Items]    
Entity Registrant Name UDR, Inc.  
Entity Central Index Key 0000074208  
Document Type 10-K  
Document Period End Date Dec. 31, 2015  
Amendment Flag false  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus FY  
Current Fiscal Year End Date --12-31  
Entity Well-known Seasoned Issuer Yes  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes  
Entity Filer Category Large Accelerated Filer  
Entity Public Float $ 3.7  
Entity Common Stock, Shares Outstanding   262,132,787
United Dominion Reality L.P.    
Entity Information [Line Items]    
Entity Registrant Name United Dominion Realty L.P.  
Entity Central Index Key 0001018254  
Document Period End Date Dec. 31, 2015  
Entity Well-known Seasoned Issuer No  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes  
Entity Filer Category Non-accelerated Filer