XML 75 R59.htm IDEA: XBRL DOCUMENT v3.21.1

Leases - Additional Information (Details)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Residential Apartment Leases [Member]
Operating Leased Assets [Line Items]
Percentage of rental income	97.00%	97.00%
Residential Apartment Leases [Member] | Maximum [Member]
Operating Leased Assets [Line Items]
Retail leases term	12 months
Non-residential Leases [Member]
Operating Leased Assets [Line Items]
Percentage of rental income	3.00%	3.00%
Non-residential Leases [Member] | Maximum [Member]
Operating Leased Assets [Line Items]
Retail leases term	10 years
Non-residential Leases [Member] | Minimum [Member]
Operating Leased Assets [Line Items]
Retail leases term	5 years

X

- Definition

Percentage of rental income.

+ References

No definition available.

+ Details

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Namespace Prefix:	eqr_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919359-209981

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

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- Details

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X

- Details

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Namespace Prefix:
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Period Type:

X

- Details

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Namespace Prefix:
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Period Type: