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Business - Additional Information (Details) | Mar. 31, 2022 State Property ApartmentUnit
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Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |
Number of states in which entity operates | State | 10
Properties | Property | 311
Apartment units | ApartmentUnit | 80,581
ERPOP [Member] |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] |
Noncontrolling interest, ownership percentage by parent | 96.70%

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- Definition Organization consolidation and presentation of financial statements disclosure. + References No definition available. + Details
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Namespace Prefix: | eqr_
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- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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- Definition The number of real estate properties owned as of the balance sheet date. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Balance Type: | na
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- Definition The number of states the entity operates in as of the balance sheet date. + References No definition available. + Details
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Balance Type: | na
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- 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_
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- Details
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Namespace Prefix: |
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