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Represents the change in the proportional relationship between the carrying values of Redeemable Limited Partners relative to that of Limited Partners.

No definition available.

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Value of Units exchanged between Limited Partners and the General Partner. Total Units outstanding remains consistent.

No definition available.

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Decrease in General Partner balance from payment of dividends or other distributions.

No definition available.

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Investments in partially owned entities.

No definition available.

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Total change in redeemable limited partners during the period due to redemptions and adjustments to redemption value of limited partners.

No definition available.

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OP unit issuance.

No definition available.

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Total of Partners' Capital (deficit) items attributable to the parent. This excludes temporary equity and is sometimes called permanent equity.

No definition available.

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Change in the value of company common shares contained in the company's supplemental executive retirement plan.

No definition available.

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Decrease in Limited Partners balance from payment of dividends or other distributions.

No definition available.

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Amount of increase in additional paid-in capital (APIC) from recognition of equity-based compensation for employee stock purchase program.

No definition available.

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Amount of increase to additional paid-in capital (APIC) resulting from recognition of equity-based compensation for restricted stock units.

No definition available.

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Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation for stock options.

No definition available.

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Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation for other long-term incentive plan.

No definition available.

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Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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No definition available.

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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Aggregate amount of net income allocated to general partners.

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Aggregate amount of net income allocated to limited partners.

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No definition available.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Total of all Partners' Capital (deficit) items which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of cash inflow from a noncontrolling interest. Includes, but is not limited to, purchase of additional shares or other increase in noncontrolling interest ownership.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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No definition available.

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Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Value of stock issued as a result of the exercise of stock options.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	dei_LegalEntityAxis=eqr_ERPOPMember
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Name:	us-gaap_PartnerTypeOfPartnersCapitalAccountAxis=us-gaap_PreferredStockMember
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