XML 104 R88.htm IDEA: XBRL DOCUMENT
v3.19.1

Subsequent Events - Additional Information (Details) $ in Thousands |  | 3 Months Ended
--- | --- | ---
May 06, 2019 USD ($) Property ApartmentUnit | Mar. 31, 2019 USD ($) Property ApartmentUnit
Subsequent Event [Line Items] |  |
Properties acquired | Property |  | 3
Property Units acquired | ApartmentUnit |  | 579
Purchase Price |  | $ 258,650
Bonds [Member] |  |
Subsequent Event [Line Items] |  |
Repayments of long-term debt | $ 95,500 |
Debt Instrument Maturity Date | 2036 |
Subsequent Event |  |
Subsequent Event [Line Items] |  |
Properties acquired | Property | 1 |
Property Units acquired | ApartmentUnit | 366 |
Purchase Price | $ 103,500 |
Number of properties sold | Property | 1 |
Number of self managed apartments | ApartmentUnit | 266 |
Amount of property sold | $ 237,500 |

X
- Definition Amount of property sold. + References No definition available. + Details
Name: | eqr_AmountOfPropertySold
Namespace Prefix: | eqr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Debt instrument maturity year. + References No definition available. + Details
Name: | eqr_DebtInstrumentMaturityYear
Namespace Prefix: | eqr_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of properties sold. + References No definition available. + Details
Name: | eqr_NumberOfPropertiesSold
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of self managed apartments. + References No definition available. + Details
Name: | eqr_NumberOfSelfManagedApartments
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total number of property or properties acquired from unaffiliated third parties during the period. + References No definition available. + Details
Name: | eqr_PropertiesAcquired
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total number of units associated with the property or properties acquired from unaffiliated third parties during the period. + References No definition available. + Details
Name: | eqr_PropertyUnitsAcquired
Namespace Prefix: | eqr_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of assets acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
Name: | us-gaap_SubsequentEventLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=eqr_TaxExemptMortgageBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |