Notes (Details 1) (USD $) In Thousands	Dec. 31, 2010	Dec. 31, 2009
Aggregate payments of principal on unsecured notes payable
2011	$ 1,068,891
2012	474,221
2013	407,849
2014	498,576
2015	298,700
Thereafter	2,436,943
Total	$ 5,185,180	$ 4,609,124

Amount of long-term debt during maturing in six or more years after the date of the latest balance sheet presented in the financial statements.

Name:	eqr_LongTermDebtMaturitiesRepaymentsOfPrincipalThereafter
Namespace Prefix:	eqr
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LongTermDebtByMaturityAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of long-term debt maturing within the next twelve months following the date of the latest balance sheet presented in the financial statements, which may include maturities of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates.

+ References