XML 65 R49.htm IDEA: XBRL DOCUMENT
v3.19.1

Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding Units (Details) - shares | 3 Months Ended
--- | ---
Mar. 31, 2019 | Mar. 31, 2018
General and Limited Partner Units |  |
Exercise of share options | 709,071 | 45,391
Employee Share Purchase Plan (ESPP) | 18,901 | 35,177
Restricted share grants, net | 144,390 | 108,261
Restricted unit grants, net | 133,214 | 263,048
Common Shares And Units Outstanding | 384,314,772 | 382,238,397
LIMITED PARTNERS |  |
Total Units Outstanding | 13,904,035 | 13,768,438
Restricted unit grants, net | 133,214 | 263,048
Conversion of Limited Partner OP Units to EQR Common Shares | (184,878) | (5,000)
Total Units Outstanding | 13,852,371 | 14,026,486
Units Ownership Interest in Operating Partnership | 3.60% | 3.70%
ERPOP [Member] |  |
General and Limited Partner Units |  |
Common Shares And Units Outstanding | 383,309,196 | 381,786,520
Exercise of share options | 709,071 | 45,391
Employee Share Purchase Plan (ESPP) | 18,901 | 35,177
Restricted share grants, net | 144,390 | 108,261
Restricted unit grants, net | 133,214 | 263,048
Common Shares And Units Outstanding | 384,314,772 | 382,238,397
LIMITED PARTNERS |  |
Total Units Outstanding | 13,904,035 | 13,768,438
Restricted unit grants, net | 133,214 | 263,048
Conversion of Limited Partner OP Units to EQR Common Shares | (184,878) | (5,000)
Total Units Outstanding | 13,852,371 | 14,026,486
Units Ownership Interest in Operating Partnership | 3.60% | 3.70%

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=27012166&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=6877327&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=6877327&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=109197908&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=27012166&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=6877327&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=6877327&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: |