The number of communities sold by the entity during the period.

No definition available.

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Namespace Prefix:	ess_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of units sold by the entity during the period.

+ References

No definition available.

+ Details

Name:	ess_NumberOfUnitsSold
Namespace Prefix:	ess_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Real Estate Investment, Ownership Sold

+ References

No definition available.

+ Details

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Namespace Prefix:	ess_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) on sale or disposal of oil and gas property or timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Revenue from the sale of commercial, industrial, or residential property during the period. This element is more likely than not relevant to an entity for which real estate operations are a principal activity. If real estate operations are not a principal activity, the reporting entity would likely use a gain (loss) on sale of property, plant, or equipment type element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Real Estate Investments Sales of Real Estate Investments(Details) $ in Millions	1 Months Ended	12 Months Ended
	Mar. 31, 2015 USD ($) community	Dec. 31, 2015 USD ($) community unit	Dec. 31, 2014 USD ($) community unit	Dec. 31, 2013 USD ($) community unit
Real Estate Properties [Line Items]
Number of communities sold \| community	2	2	4	3
Number of units sold \| unit		848	594	363
Sales Price	$ 13.0	$ 308.8	$ 120.4	$ 57.5
Gain on sale of real estate	$ 2.4	$ 44.9	$ 43.6	$ 29.2
Pinnacle South Mountain [Member]
Real Estate Properties [Line Items]
Number of units sold \| unit		552
Essex Ownership Percentage		100.00%
Sales Price		$ 63.8
Gain on sale of real estate		$ 4.7
Sharon Green [Member]
Real Estate Properties [Line Items]
Number of units sold \| unit		296
Essex Ownership Percentage		100.00%
Sales Price		$ 245.0
Gain on sale of real estate		$ 40.2