Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding General Partner Units and Limited Partner Units (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
General and Limited Partner Units
Common Shares And Units Outstanding	388,186,222	386,160,073
Issuance of OP Units	1,740,550
Exercise of share options	468,021	1,710,692	239,695
Employee Share Purchase Plan (ESPP)	66,835	70,702	90,196
Restricted share grants, net	174,575	89,593	178,720
Restricted unit grants, net	223,242	155,162	249,263
Common Shares And Units Outstanding	390,859,445	388,186,222	386,160,073
Limited Partner Units
Total Units Outstanding	12,659,027	13,858,073	13,731,315
Restricted unit grants, net	223,242	155,162	249,263
Conversion of Limited Partner OP Units to EQR Common Shares	(452,532)	(1,354,208)	(122,505)
Total Units Outstanding	12,429,737	12,659,027	13,858,073
Units Ownership Interest in Operating Partnership	3.20%	3.30%	3.60%
ERPOP [Member]
General and Limited Partner Units
Common Shares And Units Outstanding	388,186,222	386,160,073	385,402,199
Issuance of OP Units	1,740,550
Exercise of share options	468,021	1,710,692	239,695
Employee Share Purchase Plan (ESPP)	66,835	70,702	90,196
Restricted share grants, net	174,575	89,593	178,720
Restricted unit grants, net	223,242	155,162	249,263
Common Shares And Units Outstanding	390,859,445	388,186,222	386,160,073
Limited Partner Units
Total Units Outstanding	12,659,027	13,858,073	13,731,315
Restricted unit grants, net	223,242	155,162	249,263
Conversion of Limited Partner OP Units to EQR Common Shares	(452,532)	(1,354,208)	(122,505)
Total Units Outstanding	12,429,737	12,659,027	13,858,073
Units Ownership Interest in Operating Partnership	3.20%	3.30%	3.60%