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v2.4.1.9

Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified | 12 Months Ended | 3 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013
Unaudited Quarterly Financial Data [Line Items] |  |  |  |  |  |  |  |  |  |  |
Operating income | $ 921,375 us-gaap_OperatingIncomeLoss | $ 512,322 us-gaap_OperatingIncomeLoss | $ 514,093 us-gaap_OperatingIncomeLoss |  |  |  |  |  |  |  |
Income (loss) from continuing operations | 657,101 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest | (168,174)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest | 160,298 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest |  |  |  |  |  |  |  |
Discontinued operations, net | 1,582 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax | 2,073,527 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax | 720,906 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax |  |  |  |  |  |  |  |
Net income | 658,683 us-gaap_ProfitLoss | 1,905,353 us-gaap_ProfitLoss | 881,204 us-gaap_ProfitLoss |  |  |  |  |  |  |  |
Earnings Per Share, Basic [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares | $ 1.736 us-gaap_EarningsPerShareBasic | $ 5.155 us-gaap_EarningsPerShareBasic | $ 2.729 us-gaap_EarningsPerShareBasic |  |  |  |  |  |  |  |
Weighted average Common Shares outstanding | 361,181 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic | 354,305 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic | 302,701 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic |  |  |  |  |  |  |  |
Earnings Per Share, Diluted [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares | $ 1.726 us-gaap_EarningsPerShareDiluted | $ 5.155 us-gaap_EarningsPerShareDiluted | $ 2.705 us-gaap_EarningsPerShareDiluted |  |  |  |  |  |  |  |
Weighted Average Number of Shares Outstanding, Diluted | 377,735 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding | 354,305 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding | 319,766 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding |  |  |  |  |  |  |  |
Scenario, Previously Reported [Member] |  |  |  |  |  |  |  |  |  |  |
Unaudited Quarterly Financial Data [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | 664,660 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 664,078 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 652,568 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 633,442 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 639,134 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 626,629 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 617,217 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 504,722 us-gaap_SalesRevenueNet / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Operating income |  |  |  | 250,532 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 243,274 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 228,310 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 199,259 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 223,677 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 120,405 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 63,986 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 104,254 us-gaap_OperatingIncomeLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Income (loss) from continuing operations |  |  |  | 226,959 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 231,252 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 117,210 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 81,680 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 69,141 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (13,465)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (58,511)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (165,339)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Discontinued operations, net |  |  |  | 82 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (62)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 510 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,052 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 46,729 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 405,182 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 395,243 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,226,373 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Net income |  |  |  | 227,041 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 231,190 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 117,720 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 82,732 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 115,870 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 391,717 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 336,732 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,061,034 us-gaap_ProfitLoss / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Net income available to Common Shares |  |  |  | 216,703 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 220,707 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 111,654 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 78,099 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 109,940 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 376,155 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 323,723 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,016,650 eqr_NetIncomeLossAvailableToCommonStockholderBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Earnings Per Share, Basic [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares |  |  |  | $ 0.60 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.61 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.22 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 1.05 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.90 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 3.01 us-gaap_EarningsPerShareBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Weighted average Common Shares outstanding |  |  |  | 362,018 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 361,409 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 360,809 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 360,470 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 359,919 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 359,811 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 359,653 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 337,532 us-gaap_WeightedAverageNumberOfSharesOutstandingBasic / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Earnings Per Share, Diluted [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares |  |  |  | $ 0.59 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.61 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.22 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.30 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 1.05 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.90 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 3.01 us-gaap_EarningsPerShareDiluted / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Weighted Average Number of Shares Outstanding, Diluted |  |  |  | 378,886 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 377,954 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 377,118 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 376,384 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 375,860 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 359,811 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 359,653 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 337,532 us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Operating Partnership [Member] | Scenario, Previously Reported [Member] |  |  |  |  |  |  |  |  |  |  |
Unaudited Quarterly Financial Data [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  | 664,660 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 664,078 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 652,568 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 633,442 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 639,134 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 626,629 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 617,217 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 504,722 us-gaap_SalesRevenueNet / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Operating income |  |  |  | 250,532 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 243,274 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 228,310 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 199,259 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 223,677 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 120,405 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 63,986 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 104,254 us-gaap_OperatingIncomeLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Income (loss) from continuing operations |  |  |  | 226,959 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 231,252 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 117,210 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 81,680 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 69,141 us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (13,465)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (58,511)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (165,339)us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Discontinued operations, net |  |  |  | 82 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | (62)us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 510 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,052 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 46,729 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 405,182 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 395,243 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,226,373 us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Net income |  |  |  | 227,041 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 231,190 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 117,720 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 82,732 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 115,870 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 391,717 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 336,732 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 1,061,034 us-gaap_ProfitLoss / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Net income available to Units |  |  |  | $ 225,261 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 229,445 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 116,096 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 81,192 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 114,271 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 390,991 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 336,511 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 1,059,973 us-gaap_IncomeLossIncludingPortionAttributableToNoncontrollingInterest / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Earnings Per Share, Basic [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares |  |  |  | $ 0.60 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.61 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.22 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 1.05 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.90 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 3.01 us-gaap_EarningsPerShareBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Weighted average Units outstanding |  |  |  | 375,711 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 375,116 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 374,551 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 374,201 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 373,643 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 373,547 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 373,403 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 351,255 us-gaap_WeightedAverageLimitedPartnershipAndGeneralPartnershipUnitsOutstandingBasic / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Earnings Per Share, Diluted [Abstract] |  |  |  |  |  |  |  |  |  |  |
Net income available to Common Shares |  |  |  | $ 0.59 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.61 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.31 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.22 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.30 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 1.05 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 0.90 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | $ 3.01 us-gaap_EarningsPerShareDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember
Weighted average Units outstanding |  |  |  | 378,886 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 377,954 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 377,118 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 376,384 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 375,860 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 373,547 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 373,403 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember | 351,255 eqr_WeightedAverageNumberOfLimitedPartnershipAndGeneralPartnershipUnitOutstandingDiluted / dei_LegalEntityAxis = eqr_OperatingPartnershipMember / us-gaap_StatementScenarioAxis = us-gaap_ScenarioPreviouslyReportedMember

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- Definition This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses and taxes from ongoing operations before extraordinary items, and noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683 + Details
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