XML 59 R1.htm IDEA: XBRL DOCUMENT v3.2.0.727
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2015
Jul. 31, 2015
Entity Registrant Name EQUITY RESIDENTIAL  
Entity Central Index Key 0000906107  
Document Type 10-Q  
Document Period End Date Jun. 30, 2015  
Amendment Flag false  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q2  
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 Common Stock, Shares Outstanding   364,082,263
OPERATING PARTNERSHIP    
Entity Registrant Name ERP OPERATING LIMITED PARTNERSHIP  
Entity Central Index Key 0000931182  
Document Type 10-Q  
Document Period End Date Jun. 30, 2015  
Amendment Flag false  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q2  
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 Non-accelerated Filer