Name:	eqr_DisposalGroupIncludingDiscontinuedOperationAmortizationOfDeferredFinancingCosts
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives that is attributable to the disposal group. Includes production and non-production related depreciation.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationDepreciation
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The aggregate total of expenses that are attributable to the disposal group for managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrative
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The amount of interest income and other income recognized during the period attributable to the disposal group, including a component of the entity (discontinued operation).

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationInterestAndOtherIncome
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationInterestExpenseAbstract
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- Details

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationOperatingExpenseAbstract
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Data Type:	xbrli:stringItemType
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Period Type:	duration

Any other expense items resulting from secondary business-related activities, excluding those considered part of the normal operations of the business that have not been previously categorized that are attributable to the disposal group.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationOtherExpenses
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The aggregate costs of keeping the property in good condition but that do not appreciably prolong the life or increase the value of the property that are attributable to the disposal group.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationPropertyAndMaintenance
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The aggregate total of real estate taxes and insurance expense that is attributable to the disposal group.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationRealEstateTaxesAndInsurance
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue that is attributable to the disposal group.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationRentalRevenue
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationRevenueAbstract
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The aggregate total of property management expense that is attributable to the disposal group.

No definition available.

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationsPropertyManagement
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents the income (loss) from a disposal group that is classified as a component of the entity, net of income tax, reported as a separate component of income before extraordinary items, the cumulative effect of accounting changes before deduction or consideration of the amount which may be allocable to noncontrolling interests, if any, and gain (loss) on disposal.

No definition available.

Name:	eqr_IncomeLossFromDiscontinuedOperations
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of gain (loss), after tax expense or benefit and not previously recognized, resulting from the sale of a business component.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Amount of interest expense allocated to disposal group, including a discontinued operation.

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Amount of operating expenses attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of operating income or loss attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of sales or other form of revenues attributable to the disposal group, including a component of the entity (discontinued operation), during the reporting period.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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