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

- Details

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationOperatingExpenseAbstract
Namespace Prefix:	eqr_
Data Type:	xbrli:stringItemType
Balance Type:	na
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

- Details

Name:	eqr_DisposalGroupIncludingDiscontinuedOperationRevenueAbstract
Namespace Prefix:	eqr_
Data Type:	xbrli:stringItemType
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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
Namespace Prefix:	eqr_
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.

Name:	us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b),(c)

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Name:	us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation
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Period Type:	duration

Amount of general and administrative expense attributable to disposal group.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of rental income attributable to the disposal group, including a component of the entity (discontinued operation).

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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.

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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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-Subparagraph (SX 210.5-03.14)

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