Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding General Partner Units and Limited Partner Units (Details) - shares	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
General and Limited Partner Units
Exercise of share options	381,384	1,401,755
Employee Share Purchase Plan (ESPP)	49,662	59,297
Restricted share grants, net	173,351	85,573
Restricted unit grants, net	223,242	155,638
Common Shares And Units Outstanding	389,013,861	387,862,336
Limited Partner Units
Total Units Outstanding	12,659,027	13,858,073
Restricted unit grants, net	223,242	155,638
Conversion of Limited Partner OP Units to EQR Common Shares	(37,661)	(1,153,963)
Total Units Outstanding	12,844,608	12,859,748
Units Ownership Interest in Operating Partnership	3.30%	3.30%
ERPOP [Member]
General and Limited Partner Units
Common Shares And Units Outstanding	388,186,222	386,160,073
Exercise of share options	381,384	1,401,755
Employee Share Purchase Plan (ESPP)	49,662	59,297
Restricted share grants, net	173,351	85,573
Restricted unit grants, net	223,242	155,638
Common Shares And Units Outstanding	389,013,861	387,862,336
Limited Partner Units
Total Units Outstanding	12,659,027	13,858,073
Restricted unit grants, net	223,242	155,638
Conversion of Limited Partner OP Units to EQR Common Shares	(37,661)	(1,153,963)
Total Units Outstanding	12,844,608	12,859,748
Units Ownership Interest in Operating Partnership	3.30%	3.30%