Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Related party receivables	$ 144.6	$ 11.1
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	670,000,000	670,000,000
Common stock, shares issued (in shares)	66,081,635	65,890,322
Common stock, shares outstanding (in shares)	66,081,635	65,890,322
Essex Portfolio, L.P. [Member]
Related party receivables	$ 144.6	$ 11.1
Essex Portfolio, L.P. [Member] | General Partner [Member]
Common stock, shares issued (in shares)	66,081,635	65,890,322
Common stock, shares outstanding (in shares)	66,081,635	65,890,322
Essex Portfolio, L.P. [Member] | Limited Partners [Member]
Common stock, shares issued (in shares)	2,298,237	2,305,389
Common stock, shares outstanding (in shares)	2,298,237	2,305,389