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Change in capital as a result of a reallocation of General Partner's capital to Limited Partners due to the General Partner using Units.

No definition available.

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Amount of net (income) loss for the period allocated to noncontrolling partners in partially owned properties.

No definition available.

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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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The total value of the initial contributions made by participants in the Company's LTIP Unit plan during the period.

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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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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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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The cash outflow to reacquire OP Units during the period.

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.

Name:	eqr_UnitsLimitedPartnersDistributions
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This element represents the amount of recognized equity-based compensation related to employee stock purchase programs during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized).

No definition available.

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This element represents the amount of recognized equity-based compensation related to other long-term incentive plans during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized).

No definition available.

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Amount of equity-based compensation, related to restricted stock units or restricted stock awards, recognized as expense or an asset, if compensation is capitalized.

No definition available.

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This element represents the amount of recognized equity-based compensation related to stock options during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized).

No definition available.

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Aggregate amount of net income allocated to general partners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Aggregate amount of net income allocated to limited partners.

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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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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).

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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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This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy.

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.

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Value of stock issued as a result of the exercise of stock options.

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