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Represents charges to interest expense related to the extinguishment of borrowing before maturity.

No definition available.

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Total number of property or properties acquired from unaffiliated third parties during the period.

No definition available.

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The weighted average interest rate on total mortgage debt for the period.

No definition available.

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The charge to earnings for the amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized in conjunction with early debt extinguishment.

No definition available.

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Contractual interest rate for funds borrowed, under the debt agreement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
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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.

No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	xbrli:monetaryItemType
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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConventionalLoanMember
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Name:	us-gaap_LongtermDebtTypeAxis=eqr_MortgageLoanFloatingRateMember
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