Condensed Consolidated Statements of Cash Flows (Unaudited) (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Supplemental disclosure of cash flow information:
Cash paid for interest, capitalized	$ 4.3us-gaap_InterestPaidCapitalized	$ 3.1us-gaap_InterestPaidCapitalized
Essex Portfolio, L.P. [Member]
Supplemental disclosure of cash flow information:
Cash paid for interest, capitalized	$ 4.3	$ 3.1

The amount of cash paid during the current period for interest that is capitalized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

Name:	us-gaap_InterestPaidCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration