Condensed Consolidated Statement of Capital (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014
Net income	$ 26,406
Reversal of unrealized gains upon the sale of marketable securities	(427)
Changes in fair value of derivatives and amortization of swap settlements	2,720
Changes in fair value of marketable securities	(2,030)
Issuance of common stock under:
Stock and unit based compensation plan (in shares)	0
Sale of common stock by general partner	157,596
Sale of common stock by general partner (in shares)	0
Contributions from noncontrolling interest	1,419,816
Distributions to noncontrolling interests	3,969
Redemptions of noncontrolling interest	(101)
Essex Portfolio, L.P. [Member]
Balances	1,998,238
Net income	26,406
Reversal of unrealized gains upon the sale of marketable securities	(427)
Changes in fair value of derivatives and amortization of swap settlements	2,720
Changes in fair value of marketable securities	2,030
Issuance of common stock under:
Stock and unit based compensation plans	1,769
Sale of common stock by general partner	157,596
Stock and unit based compensation costs	548
Contributions from noncontrolling interest	1,419,816
Distributions to noncontrolling interests	(1,335)
Redemptions of noncontrolling interest	(101)
Distributions declared	(49,856)
Balances	3,557,404
Essex Portfolio, L.P. [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Balances	(58,940)
Net income	0
Reversal of unrealized gains upon the sale of marketable securities	(427)
Changes in fair value of derivatives and amortization of swap settlements	2,720
Changes in fair value of marketable securities	2,030
Issuance of common stock under:
Stock and unit based compensation plans	0
Sale of common stock by general partner	0
Stock and unit based compensation costs	0
Contributions from noncontrolling interest	0
Distributions to noncontrolling interests	0
Redemptions of noncontrolling interest	0
Distributions declared	0
Balances	(54,617)
Essex Portfolio, L.P. [Member] | Noncontrolling Interest [Member]
Balances	66,130
Net income	1,709
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:
Stock and unit based compensation plans	0
Sale of common stock by general partner	0
Stock and unit based compensation costs	0
Contributions from noncontrolling interest	0
Distributions to noncontrolling interests	(1,335)
Redemptions of noncontrolling interest	0
Distributions declared	0
Balances	66,504
Essex Portfolio, L.P. [Member] | General Partner [Member] | Common Equity [Member]
Balances	1,873,882
Balances (in shares)	37,421,000
Net income	21,912
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:
Stock and unit based compensation plans	1,769
Stock and unit based compensation plan (in shares)	13,000
Sale of common stock by general partner	157,596
Sale of common stock by general partner (in shares)	958,000
Stock and unit based compensation costs	(125)
Contributions from noncontrolling interest	0
Distributions to noncontrolling interests	0
Redemptions of noncontrolling interest	0
Distributions declared	(45,853)
Balances	2,009,181
Balances (in shares)	38,392,000
Essex Portfolio, L.P. [Member] | General Partner [Member] | Preferred Equity [Member]
Balances	71,209
Net income	1,368
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:
Stock and unit based compensation plans	0
Sale of common stock by general partner	0
Stock and unit based compensation costs	0
Contributions from noncontrolling interest	0
Distributions to noncontrolling interests	0
Redemptions of noncontrolling interest	0
Distributions declared	(1,368)
Balances	71,209
Essex Portfolio, L.P. [Member] | Limited Partners [Member] | Common Equity [Member]
Balances	45,957
Balances (in shares)	2,150,000
Net income	1,417
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:
Stock and unit based compensation plans	0
Sale of common stock by general partner	0
Stock and unit based compensation costs	673
Stock and unit based compensation costs (in shares)	26,000
Contributions from noncontrolling interest	1,419,816
Contributions from noncontrolling interest (in shares)	8,560,000
Distributions to noncontrolling interests	0
Redemptions of noncontrolling interest	(101)
Distributions declared	(2,635)
Balances	$ 1,465,127
Balances (in shares)	10,736,000