Condensed Consolidated Statement of Capital - USD ($) shares in Thousands, $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2016
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	$ 76,824	$ 163,731
Change in fair value of derivatives and amortization of swap settlements		(1,335)
Change in fair value of marketable securities, net		305
Issuance of common stock under:
Sale of common stock by general partner, net		(279)
Changes in the redemption value of redeemable noncontrolling interest		921
Distributions to noncontrolling interest		(13,471)
Redemptions		(2,233)
Essex Portfolio, L.P. [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		6,337,023
Net income	76,824	163,731
Change in fair value of derivatives and amortization of swap settlements		(1,335)
Change in fair value of marketable securities, net		305
Issuance of common stock under:
General partner's stock based compensation, net		11,760
Sale of common stock by general partner, net		(279)
Equity based compensation costs		3,198
Reclassification of Series H preferred stock		(73,750)
Changes in the redemption value of redeemable noncontrolling interest		921
Distributions to noncontrolling interest		(6,182)
Redemptions		(2,233)
Distributions declared		(218,083)
Balance at period end	6,215,076	6,215,076
Essex Portfolio, L.P. [Member] | Common Equity [Member] | General Partner [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		$ 6,208,535
Balance at period beginning (in shares)		65,379
Net income		$ 149,994
Issuance of common stock under:
General partner's stock based compensation, net		$ 11,760
General partner's stock based compensation, net (in shares)		89
Sale of common stock by general partner, net		$ (279)
Equity based compensation costs		2,001
Changes in the redemption value of redeemable noncontrolling interest		365
Redemptions		$ (1,743)
Redemptions (in shares)		11
Distributions declared		$ (209,480)
Balance at period end	$ 6,161,153	$ 6,161,153
Balance at period end (in shares)	65,479	65,479
Essex Portfolio, L.P. [Member] | Common Equity [Member] | Limited Partner [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		$ 47,235
Balance at period beginning (in shares)		2,215
Net income		$ 5,234
Issuance of common stock under:
Equity based compensation costs		$ 1,197
Equity based compensation costs (in shares)		18
Redemptions		$ (79)
Redemptions (in shares)		11
Distributions declared		$ (7,289)
Balance at period end	$ 46,298	$ 46,298
Balance at period end (in shares)	2,222	2,222
Essex Portfolio, L.P. [Member] | Preferred Equity [Member] | General Partner [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		$ 71,209
Net income		3,855
Issuance of common stock under:
Reclassification of Series H preferred stock		(73,750)
Distributions declared		(1,314)
Balance at period end	$ 0	0
Essex Portfolio, L.P. [Member] | Accumulated Other Comprehensive Loss, Net [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		(39,598)
Change in fair value of derivatives and amortization of swap settlements		(1,335)
Change in fair value of marketable securities, net		305
Issuance of common stock under:
Balance at period end	(40,628)	(40,628)
Essex Portfolio, L.P. [Member] | Noncontrolling Interest [Member]
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning		49,642
Net income		4,648
Issuance of common stock under:
Changes in the redemption value of redeemable noncontrolling interest		556
Distributions to noncontrolling interest		(6,182)
Redemptions		(411)
Balance at period end	$ 48,253	$ 48,253