XML 96 R80.htm IDEA: XBRL DOCUMENT v3.21.1

Commitments and Contingencies - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) Property ApartmentUnit Agreement
Commitments And Contingencies [Abstract]
Projects in various stages of development	2
Partially owned projects in various stages of development	1
Units in various stages of development | ApartmentUnit	824
Consolidated project under development commitment fund | $	$ 126.8
Various stages of development with estimated completion dates ranging through December 31, 2021	Dec. 31, 2021
Number of joint venture agreements | Agreement	2

X

- Definition

Commitments and Contingencies.

+ References

No definition available.

+ Details

Name:	eqr_CommitmentsAndContingenciesAbstract
Namespace Prefix:	eqr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Represents the company's remaining funding obligation (i.e. total project costs less book value) for consolidated projects that are under development.

+ References

No definition available.

+ Details

Name:	eqr_ConsolidatedProjectUnderDevelopmentCommitmentFund
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Number of joint venture agreements.

+ References

No definition available.

+ Details

Name:	eqr_NumberOfJointVentureAgreements
Namespace Prefix:	eqr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of partially owned projects in various stages of development.

+ References

No definition available.

+ Details

Name:	eqr_NumberOfPartiallyOwnedProjectsInVariousStagesOfDevelopment
Namespace Prefix:	eqr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Total number of open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. These projects are consolidated.

+ References

No definition available.

+ Details

Name:	eqr_NumberOfProjectsInVariousStagesOfDevelopment
Namespace Prefix:	eqr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Total number of units that are associated with open development projects. May include projects that are held for and/or under development, completed and not stabilized or completed and stabilized. These units are consolidated.

+ References

No definition available.

+ Details

Name:	eqr_NumberOfUnitsInVariousStagesOfDevelopment
Namespace Prefix:	eqr_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Represents the latest completion date for the current projects under development.

+ References

No definition available.

+ Details

Name:	eqr_VariousStagesOfDevelopmentDateMaturity
Namespace Prefix:	eqr_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration