XML 74 R55.htm IDEA: XBRL DOCUMENT v3.20.4

Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding General Partner Units and Limited Partner Units (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
General and Limited Partner Units
Common Shares And Units Outstanding	385,402,199	383,309,196
Exercise of share options	239,695	1,745,050	1,056,388
Employee Share Purchase Plan (ESPP)	90,196	48,131	75,414
Restricted share grants, net	178,720	158,602	123,800
Restricted unit grants, net	249,263	141,220	267,074
Common Shares And Units Outstanding	386,160,073	385,402,199	383,309,196
Limited Partner Units
Total Units Outstanding	13,731,315	13,904,035	13,768,438
Restricted unit grants, net	249,263	141,220	267,074
Conversion of Limited Partner OP Units to EQR Common Shares	(122,505)	(313,940)	(131,477)
Total Units Outstanding	13,858,073	13,731,315	13,904,035
Units Ownership Interest in Operating Partnership	3.60%	3.60%	3.60%
ERPOP [Member]
General and Limited Partner Units
Common Shares And Units Outstanding	385,402,199	383,309,196	381,786,520
Exercise of share options	239,695	1,745,050	1,056,388
Employee Share Purchase Plan (ESPP)	90,196	48,131	75,414
Restricted share grants, net	178,720	158,602	123,800
Restricted unit grants, net	249,263	141,220	267,074
Common Shares And Units Outstanding	386,160,073	385,402,199	383,309,196
Limited Partner Units
Total Units Outstanding	13,731,315	13,904,035	13,768,438
Restricted unit grants, net	249,263	141,220	267,074
Conversion of Limited Partner OP Units to EQR Common Shares	(122,505)	(313,940)	(131,477)
Total Units Outstanding	13,858,073	13,731,315	13,904,035
Units Ownership Interest in Operating Partnership	3.60%	3.60%	3.60%

X

- Definition

Number of all classes of common stock held by shareholders, which is net of related treasury stock, and number of all Operating Partnership Units held by various individuals and entities that contributed their properties to the Operating Partnership.

+ References

No definition available.

+ Details

Name:	eqr_CommonSharesAndUnitsOutstanding
Namespace Prefix:	eqr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Number of units issued during the period as a result of a long-term incentive plan.

+ References

No definition available.

+ Details

Name:	eqr_IssuanceOfLtips
Namespace Prefix:	eqr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The number of restricted shares granted during the reporting period, net of cancellations.

+ References

No definition available.

+ Details

Name:	eqr_RestrictedShareGrantsNet
Namespace Prefix:	eqr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

OP Units converted into shares of stock during the period. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit). Subject to certain exceptions, this unit can be exchanged for Common Shares on a one-for-one basis.

+ References

No definition available.

+ Details

Name:	eqr_SharesIssuedDuringPeriodSharesConversionOfUnitsToCommonShares
Namespace Prefix:	eqr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Units outstanding.

+ References

No definition available.

+ Details

Name:	eqr_UnitsOutstanding
Namespace Prefix:	eqr_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Represents the noncontrolling interests (comprised of Units and LTIP Units) ownership interest in the Operating Partnership.

+ References

No definition available.

+ Details

Name:	eqr_UnitsOwnershipInterestInOperatingPartnership
Namespace Prefix:	eqr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- References

No definition available.

+ Details

Name:	us-gaap_GeneralAndLimitedPartnersCapitalAccountAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_LimitedPartnersCapitalAccountAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

+ Details

Name:	us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	dei_LegalEntityAxis=eqr_ERPOPMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: