Equity, Capital and Other Interests EQR Common Shares (Details)	9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013
Common Shares of beneficial interest, shares outstanding	362,208,087	360,479,260
Common Shares Issued:
Conversion of OP Units	68,296
Exercise of share options	1,476,512
Employee Share Purchase Plan (ESPP)	56,945
Restricted Share Grants Net	170,460
Conversion Of Restricted Shares To Ltip Units Shares	(12,146)
Stock Repurchased And Retired	(31,240)
Units
Common Shares And Units Outstanding	376,533,153
Units Ownership Interest in Operating Partnership	3.80%
Limited Partner [Member]
Limited Partners' Capital Account, Units Outstanding	14,325,066	14,180,376
Common Shares Issued:
Conversion of OP Units	(68,296)
Conversion Of Restricted Shares To Ltip Units Shares	12,146
Units
Issuance Of LTIPs	200,840