Payments to acquired interest in consolidated operating property.

No definition available.

Name:	eqr_PaymentsToAcquiredInterestInConsolidatedOperatingProperty
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage interest acquired in consolidated operating property.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The percentage rate used to calculate dividend payments on preferred shares/preference units.

+ References

No definition available.

+ Details

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Namespace Prefix:	eqr_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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

- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3213-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- 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

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- Details

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- Details

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- Details

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- Details

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Subsequent Events - Additional Information (Details) $ in Thousands		3 Months Ended		12 Months Ended
	Apr. 01, 2023 USD ($)	Mar. 31, 2023 ApartmentUnit	Mar. 31, 2022 USD ($)	Dec. 31, 2022
Subsequent Event [Line Items]
Apartment units \| ApartmentUnit		79,351
Payments to acquire real estate			$ 113,046
Preferred Stock [Member]
Subsequent Event [Line Items]
Preferred stock preference units dividend rate percentage		8.29%		8.29%
Subsequent Events [Member]
Subsequent Event [Line Items]
Percentage interest in consolidated operating property	10.00%
Payments to acquired interest in consolidated operating property	$ 4,600
Subsequent Events [Member] \| Cash [Member]
Subsequent Event [Line Items]
Payments to acquired interest in consolidated operating property	3,700
Subsequent Events [Member] \| Mortgages [Member]
Subsequent Event [Line Items]
Payments to acquired interest in consolidated operating property	64,700
Subsequent Events [Member] \| Preferred Stock [Member]
Subsequent Event [Line Items]
Payments to acquired interest in consolidated operating property	$ 900
Preferred stock preference units dividend rate percentage	3.00%