Commitments and Contingencies - Additional Information (Details) $ in Millions	3 Months Ended
Mar. 31, 2023 USD ($) Investment
Commitments And Contingencies [Abstract]
Number of real estate investment funds \| Investment	9
Real estate technology and other real estate investments commitment funds \| $	$ 18.7

Real estate technology and other real estate investments commitment funds.

No definition available.

Name:	eqr_RealEstateTechnologyAndOtherRealEstateInvestmentsCommitmentFunds
Namespace Prefix:	eqr_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant