Net Income Per Common Share and Net Income Per Common Unit - Schedule of Net Income Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Basic:
Net income available to common stockholders/unitholders	$ 98,069	$ 164,621	$ 266,717	$ 589,093
Weighted average common shares/units (in shares)	64,290,878	64,404,008	64,336,608	64,368,625
Per common share/unit amount (in dollars per share)	$ 1.53	$ 2.56	$ 4.15	$ 9.15
Diluted:
Net income available to common stockholders/unitholders	$ 98,069	$ 164,621	$ 266,717	$ 589,093
Weighted average common shares/units (in shares)	64,311,993	64,418,240	64,350,275	64,392,244
Per common share/unit amount (in dollars per share)	$ 1.52	$ 2.56	$ 4.14	$ 9.15
Essex Portfolio, L.P.
Basic:
Net income available to common stockholders/unitholders	$ 101,399	$ 170,388	$ 275,839	$ 609,920
Weighted average common shares/units (in shares)	66,474,822	66,660,423	66,534,750	66,643,952
Per common share/unit amount (in dollars per share)	$ 1.53	$ 2.56	$ 4.15	$ 9.15
Diluted:
Net income available to common stockholders/unitholders	$ 101,399	$ 170,388	$ 275,839	$ 609,920
Weighted average common shares/units (in shares)	66,495,937	66,674,655	66,548,417	66,667,571
Per common share/unit amount (in dollars per share)	$ 1.52	$ 2.56	$ 4.14	$ 9.15
Stock options
Basic:
Effect of dilutive securities	$ 0	$ 0	$ 0	$ 0
Effect of dilutive securities (in shares)	21,115	14,232	13,667	23,619
Stock options | Essex Portfolio, L.P.
Basic:
Effect of dilutive securities	$ 0	$ 0	$ 0	$ 0
Effect of dilutive securities (in shares)	21,115	14,232	13,667	23,619