XML 69 R60.htm IDEA: XBRL DOCUMENT v2.4.1.9
Reportable Segments (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Reportable Segments      
Assets $ 23,029,048us-gaap_Assets   $ 22,950,614us-gaap_Assets
Payments to Acquire Other Property, Plant, and Equipment 38,170us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment    
Rental income:      
Total Rental Income 664,606eqr_SegmentReportingInformationRevenues 630,725eqr_SegmentReportingInformationRevenues  
Operating expenses:      
Total Operating Expenses 232,436eqr_SegmentReportingSegmentOperatingExpenses 229,778eqr_SegmentReportingSegmentOperatingExpenses  
NOI:      
Total NOI 432,170eqr_SegmentReportingInformationNetOperatingIncome 400,947eqr_SegmentReportingInformationNetOperatingIncome  
Reportable Segments (Textuals) [Abstract]      
Units in same store properties 97,586eqr_NumberOfUnitsInSameStoreProperties    
Rental income 664,606us-gaap_OperatingLeasesIncomeStatementLeaseRevenue 630,725us-gaap_OperatingLeasesIncomeStatementLeaseRevenue  
Property and maintenance expense (124,560)us-gaap_CostOfPropertyRepairsAndMaintenance (125,566)us-gaap_CostOfPropertyRepairsAndMaintenance  
Real estate taxes and insurance expense (86,432)us-gaap_RealEstateTaxesAndInsurance (82,094)us-gaap_RealEstateTaxesAndInsurance  
Property management expense (21,444)us-gaap_OwnedPropertyManagementCosts (22,118)us-gaap_OwnedPropertyManagementCosts  
Total Operating Expenses (232,436)eqr_TotalOperatingExpenses (229,778)eqr_TotalOperatingExpenses  
Non-same store [Domain]      
Reportable Segments      
Assets 3,609,209us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 2,862us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
   
Same Store [Domain]      
Rental income:      
Same store - Rental Income 632,034eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
601,794eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 216,544eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
213,460eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 415,490eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
388,334eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Boston [Domain]      
Reportable Segments      
Assets 1,908,859us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 3,505us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 64,033eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
61,907eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 22,541eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
22,129eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 41,492eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
39,778eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Denver [Domain]      
Reportable Segments      
Assets 514,958us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 1,120us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 28,997eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
26,612eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 7,460eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
7,461eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 21,537eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
19,151eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_DenverDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | New York [Domain]      
Reportable Segments      
Assets 4,637,217us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 3,797us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 116,070eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
111,186eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 46,113eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
45,834eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 69,957eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
65,352eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NewYorkDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | San Francisco [Domain]      
Reportable Segments      
Assets 2,700,366us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 5,638us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 89,850eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
81,261eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 27,103eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
26,609eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 62,747eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
54,652eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SanFranciscoDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Seattle [Domain]      
Reportable Segments      
Assets 1,088,728us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 3,524us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 40,390eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
37,621eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 12,667eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
12,734eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 27,723eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
24,887eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | South Florida [Domain]      
Reportable Segments      
Assets 1,126,085us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 2,942us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 49,302eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
46,896eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 17,968eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
17,525eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 31,334eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
29,371eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Southern California [Domain]      
Reportable Segments      
Assets 2,787,871us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 6,020us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 105,193eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
99,776eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 34,126eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
33,545eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 71,067eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
66,231eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Washington DC [Domain]      
Reportable Segments      
Assets 4,250,738us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 7,113us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 112,627eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
111,804eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 38,539eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
37,809eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 74,088eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
73,995eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Non-Core [Domain]      
Reportable Segments      
Assets 405,017us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 1,649us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Rental income:      
Same store - Rental Income 25,572eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
24,731eqr_SegmentReportingSegmentSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Operating expenses:      
Same store - Operating Expenses 10,027eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
9,814eqr_SegmentReportingSegmentSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
NOI:      
Same store - NOI 15,545eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
14,917eqr_SegmentReportingInformationSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonCoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
 
Same Store [Domain] | Same Store [Domain]      
Reportable Segments      
Assets 19,419,839us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SameStoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 35,308us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SameStoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_SameStoreDomain
   
Non-same store [Domain] | Boston [Domain]      
Reportable Segments      
Assets 47,996us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 34us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 922eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
1,028eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 229eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
210eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI 693eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
818eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_BostonDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | Seattle [Domain]      
Reportable Segments      
Assets 231,258us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 466us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 4,579eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
107eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 1,298eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
146eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI 3,281eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
(39)eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SeattleDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | South Florida [Domain]      
Reportable Segments      
Assets 66,906us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 14us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 1,932eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
803eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 675eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
454eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI 1,257eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
349eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthFloridaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | Southern California [Domain]      
Reportable Segments      
Assets 845,902us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 1,163us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 17,777eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
8,905eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 6,528eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
3,690eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI 11,249eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
5,215eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_SouthernCaliforniaDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | Washington DC [Domain]      
Reportable Segments      
Assets 242,360us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 1,143us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 5,408eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
3,507eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 1,653eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
1,441eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI 3,755eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
2,066eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_WashingtonDCDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | Other (3) [Domain]      
Reportable Segments      
Assets 2,174,787us-gaap_Assets
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Payments to Acquire Other Property, Plant, and Equipment 42us-gaap_PaymentsToAcquireOtherPropertyPlantAndEquipment
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
   
Rental income:      
Non-same store - Rental Income 1,954eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
14,581eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 5,509eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
10,377eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI (3,555)eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
4,204eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_OtherDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Non-same store [Domain] | Non-same store [Domain]      
Rental income:      
Non-same store - Rental Income 32,572eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
28,931eqr_SegmentReportingSegmentNonSameStoreRentalIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
Operating expenses:      
Non-same store - Operating Expenses 15,892eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
16,318eqr_SegmentReportingSegmentNonSameStoreOperatingExpenses
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
 
NOI:      
Non-same store - NOI $ 16,680eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain
$ 12,613eqr_SegmentReportingInformationNonSameStoreNetOperatingIncome
/ us-gaap_StatementBusinessSegmentsAxis
= eqr_NonsamestoreDomain
/ us-gaap_StatementScenarioAxis
= eqr_NonsamestoreDomain