Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Due from related parties	$ 41.2	$ 11.3
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	670,000,000	670,000,000
Common stock, shares issued	66,054,399	65,527,993
Common stock, shares outstanding	66,054,399	65,527,993
Essex Portfolio, L.P. [Member]
Due from related parties	$ 41.2	$ 11.3
Essex Portfolio, L.P. [Member] | General Partner [Member]
Common stock, shares issued	66,054,399	65,527,993
Common stock, shares outstanding	66,054,399	65,527,993
Essex Portfolio, L.P. [Member] | Limited Partner [Member]
Common stock, shares issued	2,268,114	2,237,290
Common stock, shares outstanding	2,268,114	2,237,290