Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding General Partner Units and Limited Partner Units (Details) - shares	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
General and Limited Partner Units
Exercise of share options	232,317	348,510
Employee Share Purchase Plan (ESPP)	40,346	35,669
Restricted share grants, net	149,722	175,970
Restricted unit grants, net	166,344	223,242
Common Shares And Units Outstanding	391,448,174	388,969,613
Limited Partner Units
Total Units Outstanding	12,429,737	12,659,027
Restricted unit grants, net	166,344	223,242
Conversion of Limited Partner OP Units to EQR Common Shares	(180,629)	(31,089)
Total Units Outstanding	12,415,452	12,851,180
Units Ownership Interest in Operating Partnership	3.20%	3.30%
ERPOP [Member]
General and Limited Partner Units
Common Shares And Units Outstanding	390,859,445	388,186,222
Exercise of share options	232,317	348,510
Employee Share Purchase Plan (ESPP)	40,346	35,669
Restricted share grants, net	149,722	175,970
Restricted unit grants, net	166,344	223,242
Common Shares And Units Outstanding	391,448,174	388,969,613
Limited Partner Units
Total Units Outstanding	12,429,737	12,659,027
Restricted unit grants, net	166,344	223,242
Conversion of Limited Partner OP Units to EQR Common Shares	(180,629)	(31,089)
Total Units Outstanding	12,415,452	12,851,180
Units Ownership Interest in Operating Partnership	3.20%	3.30%