Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized	670,000,000	656,020,000
Common stock, shares issued	65,527,993	65,379,359
Common stock, shares outstanding	65,527,993	65,379,359
Series H 7.125% Cumulative Redeemable Preferred Stock [Member]
Cumulative dividend rate (in hundredths)	0.00%	7.125%
Essex Portfolio, L.P. [Member] \| Series H 7.125% Cumulative Redeemable Preferred Stock [Member]
Cumulative dividend rate (in hundredths)	0.00%	7.125%
General Partner [Member] \| Essex Portfolio, L.P. [Member]
Common stock, shares issued	65,527,993	65,379,359
Common stock, shares outstanding	65,527,993	65,379,359
Preferred interest, liquidation value	$ 0	$ 73,750
Limited Partner [Member] \| Essex Portfolio, L.P. [Member]
Common stock, shares issued	2,237,290	2,214,545
Common stock, shares outstanding	2,237,290	2,214,545

Face amount or stated value per share of common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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The percentage rate used to calculate dividend payments on preferred stock.

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Value of the difference between preference in liquidation and the par or stated values of the preferred shares.

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