Equity, Capital and Other Interests - Changes in Operating Partnership's Issued and Outstanding General Partner Units and Limited Partner Units (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
General and Limited Partner Units
Exercise of share options	173,249	269,665
Employee Share Purchase Plan (ESPP)	27,393	13,374
Restricted share grants, net	123,304	157,080
Restricted unit grants, net	229,913	220,333
Common Shares And Units Outstanding	391,413,304	388,846,674
Limited Partner Units
Total Units Outstanding	12,429,737	12,659,027
Restricted unit grants, net	229,913	220,333
Conversion of Limited Partner OP Units to EQR Common Shares	(144,567)	(6,756)
Total Units Outstanding	12,515,083	12,872,604
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	173,249	269,665
Employee Share Purchase Plan (ESPP)	27,393	13,374
Restricted share grants, net	123,304	157,080
Restricted unit grants, net	229,913	220,333
Common Shares And Units Outstanding	391,413,304	388,846,674
Limited Partner Units
Total Units Outstanding	12,429,737	12,659,027
Restricted unit grants, net	229,913	220,333
Conversion of Limited Partner OP Units to EQR Common Shares	(144,567)	(6,756)
Total Units Outstanding	12,515,083	12,872,604
Units Ownership Interest in Operating Partnership	3.20%	3.30%