Condensed Consolidated Statement of Capital (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014
Net income	$ 58,684	$ 89,312
Reversal of unrealized gains upon the sale of marketable securities		(886)
Changes in fair value of derivatives and amortization of swap settlements		7,732
Changes in fair value of marketable securities		2,591
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		3,777,646
Sale of common stock by general partner		449,499
Reclassification of noncontrolling interest to redeemable noncontrolling interest		(20,890)
Changes in value of redemption value of redeemable Non-Controlling Interest		2,126
Conversion of Series G preferred stock		4,349
Contributions from noncontrolling interest		1,419,816
Retirement of noncontrolling interest		(1,419,816)
Distributions to noncontrolling interests		(12,821)
Redemptions		(2,979)
Essex Portfolio, L.P. [Member]
Balances		1,998,238
Net income	58,684	89,312
Reversal of unrealized gains upon the sale of marketable securities		(886)
Changes in fair value of derivatives and amortization of swap settlements		7,732
Changes in fair value of marketable securities		2,591
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		3,777,646
General partner's stock based compensation		6,511
Sale of common stock by general partner		449,499
Equity based compensation costs		7,428
Reclassification of noncontrolling interest to redeemable noncontrolling interest		(20,890)
Changes in value of redemption value of redeemable Non-Controlling Interest		2,126
Conversion of Series G preferred stock		4,349
Contributions from noncontrolling interest		1,419,816
Retirement of noncontrolling interest		(1,419,816)
Distributions to noncontrolling interests		(3,462)
Redemptions		(2,981)
Distributions declared		(223,770)
Balances	6,093,443	6,093,443
Essex Portfolio, L.P. [Member] | Accumulated Other Comprehensive (Loss) Income [Member]
Balances		(58,940)
Net income		0
Reversal of unrealized gains upon the sale of marketable securities		(886)
Changes in fair value of derivatives and amortization of swap settlements		7,732
Changes in fair value of marketable securities		2,591
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		0
General partner's stock based compensation		0
Sale of common stock by general partner		0
Equity based compensation costs		0
Reclassification of noncontrolling interest to redeemable noncontrolling interest		0
Conversion of Series G preferred stock		0
Contributions from noncontrolling interest		0
Retirement of noncontrolling interest		0
Distributions to noncontrolling interests		0
Redemptions		0
Distributions declared		0
Balances	(49,503)	(49,503)
Essex Portfolio, L.P. [Member] | Noncontrolling Interest [Member]
Balances		66,130
Net income		5,529
Reversal of unrealized gains upon the sale of marketable securities		0
Changes in fair value of derivatives and amortization of swap settlements		0
Changes in fair value of marketable securities		0
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		0
General partner's stock based compensation		0
Sale of common stock by general partner		0
Equity based compensation costs		0
Reclassification of noncontrolling interest to redeemable noncontrolling interest		(5,084)
Conversion of Series G preferred stock		0
Contributions from noncontrolling interest		0
Retirement of noncontrolling interest		0
Distributions to noncontrolling interests		(3,462)
Redemptions		(308)
Distributions declared		0
Balances	62,805	62,805
Essex Portfolio, L.P. [Member] | General Partner [Member] | Common Equity [Member]
Balances		1,873,882
Balances (in shares)		37,421,000
Net income		76,364
Reversal of unrealized gains upon the sale of marketable securities		0
Changes in fair value of derivatives and amortization of swap settlements		0
Changes in fair value of marketable securities		0
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		3,777,646
Common stock issued as consideration by general partner in merger (in shares)		23,093,000
General partner's stock based compensation		6,511
General partner's stock based compensation (in shares)		154,000
Sale of common stock by general partner		449,499
Sale of common stock by general partner (in shares)		2,527,000
Equity based compensation costs		5,756
Reclassification of noncontrolling interest to redeemable noncontrolling interest		(19,823)
Changes in value of redemption value of redeemable Non-Controlling Interest		2,126
Conversion of Series G preferred stock		4,349
Conversion of Series G preferred stock (in shares)		34,000
Contributions from noncontrolling interest		0
Retirement of noncontrolling interest		0
Distributions to noncontrolling interests		0
Redemptions		(2,382)
Distributions declared		(210,435)
Balances	5,963,493	5,963,493
Balances (in shares)	63,229,000	63,229,000
Essex Portfolio, L.P. [Member] | General Partner [Member] | Preferred Equity [Member]
Balances		71,209
Net income		3,977
Reversal of unrealized gains upon the sale of marketable securities		0
Changes in fair value of derivatives and amortization of swap settlements		0
Changes in fair value of marketable securities		0
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		0
General partner's stock based compensation		0
Sale of common stock by general partner		0
Equity based compensation costs		0
Reclassification of noncontrolling interest to redeemable noncontrolling interest		0
Conversion of Series G preferred stock		0
Contributions from noncontrolling interest		0
Retirement of noncontrolling interest		0
Distributions to noncontrolling interests		0
Redemptions		0
Distributions declared		(3,977)
Balances	71,209	71,209
Essex Portfolio, L.P. [Member] | Limited Partners [Member] | Common Equity [Member]
Balances		45,957
Balances (in shares)		2,150,000
Net income		3,442
Reversal of unrealized gains upon the sale of marketable securities		0
Changes in fair value of derivatives and amortization of swap settlements		0
Changes in fair value of marketable securities		0
Issuance of common stock under:
Common stock issued as consideration by general partner in merger		0
Common stock issued as consideration by general partner in merger (in shares)		0
General partner's stock based compensation		0
General partner's stock based compensation (in shares)		0
Sale of common stock by general partner		0
Sale of common stock by general partner (in shares)		0
Equity based compensation costs		1,672
Equity based compensation costs (in shares)		29,000
Reclassification of noncontrolling interest to redeemable noncontrolling interest		4,017
Reclassification of noncontrolling interest to redeemable noncontrolling interest (in shares)		(23,000)
Conversion of Series G preferred stock		0
Conversion of Series G preferred stock (in shares)		0
Contributions from noncontrolling interest		1,419,816
Contributions from noncontrolling interest (in shares)		8,561,000
Retirement of noncontrolling interest		(1,419,816)
Retirement of noncontrolling interest (in shares)		(8,561,000)
Distributions to noncontrolling interests		0
Redemptions		(291)
Distributions declared		(9,358)
Balances	$ 45,439	$ 45,439
Balances (in shares)	2,156,000	2,156,000