Condensed Consolidated Statement of Capital - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income	$ 90,076	$ 98,061	$ 418,841	$ 223,566
Reversal of unrealized gains upon the sale of marketable debt securities		(65)		(32)
Cash flow hedge losses reclassified to earnings	3,282		3,282
Change in fair value of derivatives and amortization of swap settlements	779	(4,361)	(8,003)	(6,354)
Change in fair value of marketable debt securities, net	35	105	(270)	228
Issuance of common stock under:
Sale of common stock by general partner, net	(63)	(62)	(133)	(82)
Retirement of common units, net	(20,093)		(196,404)	(56,989)
Changes in the redemption value of redeemable noncontrolling interest	(598)	339	4,169	(1,428)
Changes in noncontrolling interest from acquisition		65,472	1,349	65,472
Distributions to noncontrolling interest	(8,133)	(6,944)	(16,012)	(14,108)
Redemptions	(335)	(1,966)	(1,703)	(14,179)
Essex Portfolio, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning	6,417,949	6,317,195	6,403,504	6,393,844
Net income	90,076	98,061	418,841	223,566
Reversal of unrealized gains upon the sale of marketable debt securities		(65)		(32)
Cash flow hedge losses reclassified to earnings	3,282		3,282
Change in fair value of derivatives and amortization of swap settlements	779	(4,361)	(8,003)	(6,354)
Change in fair value of marketable debt securities, net	35	105	(270)	228
Issuance of common stock under:
General partner's stock based compensation, net	536	2,024	9,201	5,228
Sale of common stock by general partner, net	(63)	(62)	(133)	(82)
Equity based compensation costs	5,235	3,500	6,933	6,100
Retirement of common units, net	(20,093)		(196,404)	(56,989)
Cumulative effect upon adoption of ASU No. 2016-13	6,352,881	6,345,116	6,352,881	6,393,844
Changes in the redemption value of redeemable noncontrolling interest	(598)	339	4,169	(1,428)
Changes in noncontrolling interest from acquisition		65,472	1,349	65,472
Distributions to noncontrolling interest	(3,366)	(2,443)	(6,473)	(5,110)
Redemptions	(335)	(1,966)	(1,703)	(14,179)
Partners' capital account, distributions declared	(140,556)	(132,683)	(281,222)	(265,329)
Balance at period end	$ 6,352,881	$ 6,345,116	$ 6,352,881	$ 6,345,116
Essex Portfolio, L.P. | Common Equity | General Partner
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning (in shares)	65,412	65,716	66,092	65,890
Balance at period beginning	$ 6,250,833	$ 6,206,074	$ 6,234,315	$ 6,280,290
Net income	$ 84,458	$ 92,275	$ 399,464	$ 211,133
Issuance of common stock under:
General partner's stock based compensation, net (in shares)	6	11	95	62
General partner's stock based compensation, net	$ 536	$ 2,024	$ 9,201	$ 5,228
Sale of common stock by general partner, net (in shares)	0		0	0
Sale of common stock by general partner, net	$ (63)	(62)	$ (133)	$ (82)
Equity based compensation costs	$ 5,058	3,171	$ 6,677	$ 5,472
Retirement of common units, net (in shares)	(88)		(864)	(234)
Retirement of common units, net	$ (20,093)		$ (196,404)	$ (56,989)
Cumulative effect upon adoption of ASU No. 2016-13	6,184,784	6,173,899	6,184,784	6,280,290
Changes in the redemption value of redeemable noncontrolling interest	$ (199)	$ 288	$ 4,542	$ (2,739)
Redemptions (in shares)	(1)	0	(8)	(9)
Redemptions	$ 43	$ (1,689)	$ (1,005)	$ (12,083)
Partners' capital account, distributions declared	$ (135,789)	$ (128,182)	$ (271,683)	$ (256,331)
Balance at period end (in shares)	65,331	65,727	65,331	65,727
Balance at period end	$ 6,184,784	$ 6,173,899	$ 6,184,784	$ 6,173,899
Essex Portfolio, L.P. | Common Equity | Limited Partners
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning (in shares)	2,296	2,299	2,302	2,305
Balance at period beginning	$ 63,550	$ 58,667	$ 57,359	$ 59,061
Net income	$ 2,964	$ 3,228	$ 13,950	$ 7,399
Issuance of common stock under:
Equity based compensation costs (in shares)	0	0	2	3
Equity based compensation costs	$ 177	$ 329	$ 256	$ 628
Cumulative effect upon adoption of ASU No. 2016-13	61,437	57,726	57,359	59,061
Changes in the redemption value of redeemable noncontrolling interest	$ (398)	$ 4	$ (416)	$ 2
Redemptions (in shares)	0	0	(8)	(9)
Redemptions	$ (89)	$ (1)	$ (173)	$ (366)
Partners' capital account, distributions declared	$ (4,767)	$ (4,501)	$ (9,539)	$ (8,998)
Balance at period end (in shares)	2,296	2,299	2,296	2,299
Balance at period end	$ 61,437	$ 57,726	$ 61,437	$ 57,726
Essex Portfolio, L.P. | Accumulated Other Comprehensive Loss
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning	(19,519)	(11,394)	(10,432)	(9,738)
Reversal of unrealized gains upon the sale of marketable debt securities		(65)		(32)
Cash flow hedge losses reclassified to earnings	3,282		3,282
Change in fair value of derivatives and amortization of swap settlements	779	(4,361)	(8,003)	(6,354)
Change in fair value of marketable debt securities, net	35	105	(270)	228
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	(15,423)	(15,715)	(15,423)	(9,738)
Balance at period end	(15,423)	(15,715)	(15,423)	(15,715)
Essex Portfolio, L.P. | Noncontrolling Interest
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning	123,085	63,848	122,262	64,231
Net income	2,654	2,558	5,427	5,034
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13	122,083	129,206	122,262	64,231
Changes in the redemption value of redeemable noncontrolling interest	(1)	47	43	1,309
Changes in noncontrolling interest from acquisition		65,472	1,349	65,472
Distributions to noncontrolling interest	(3,366)	(2,443)	(6,473)	(5,110)
Redemptions	(289)	(276)	(525)	(1,730)
Balance at period end	$ 122,083	$ 129,206	122,083	129,206
Cumulative Effect, Period Of Adoption, Adjustment | Essex Portfolio, L.P.
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning			(190)	181
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13			(190)	181
Cumulative Effect, Period Of Adoption, Adjustment | Essex Portfolio, L.P. | Common Equity
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning			(190)	0
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13			$ (190)	0
Cumulative Effect, Period Of Adoption, Adjustment | Essex Portfolio, L.P. | Accumulated Other Comprehensive Loss
Increase (Decrease) in Partners' Capital [Roll Forward]
Balance at period beginning				181
Issuance of common stock under:
Cumulative effect upon adoption of ASU No. 2016-13				$ 181