Equity and Redeemable Noncontrolling Interests of Equity Residential (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Common Shares of beneficial interest, shares outstanding	365,550,636	364,755,444
Common Shares Issued:
Conversion of OP Units	9,840
Exercise of share options	599,634
Employee Share Purchase Plan (ESPP)	33,065
Restricted share grants, net	152,653
Units
Common Shares And Units Outstanding	380,257,233
Units Ownership Interest in Operating Partnership	3.90%
Redeemable Noncontrolling Interests – Operating Partnership	$ 478,324	$ 566,783
Change in market value of Redeemable Noncontrolling Interests – Operating Partnership	(99,190)
Change in carrying value of Redeemable Noncontrolling Interests – Operating Partnership	$ 10,731
ERPOP [Member]
Common Shares Issued:
Conversion of OP Units	(9,840)
Exercise of share options	599,634
Employee Share Purchase Plan (ESPP)	33,065
Restricted share grants, net	152,653
Units
Total Units Outstanding	14,706,597	14,427,164
Restricted unit grants, net	289,273
Shares Issued During Period Shares Conversion Of Units To Common Shares	(9,840)
Common Shares And Units Outstanding	380,257,233	379,182,608
Units Ownership Interest in Operating Partnership	3.90%