Deferred Income Tax Expense (Benefit), Real Estate

No definition available.

Name:	ess_DeferredIncomeTaxExpenseBenefitRealEstate
Namespace Prefix:	ess_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	ess_NumberOfCommunitiesSold
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

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

- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainLossOnSaleOfProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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=98514028&loc=d3e3602-108585

+ Details

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

- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

+ Details

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

- Definition

Represents properties which were acquired directly or through foreclosure for which a committed plan to sell exists and an active program to market such properties has been initiated.

+ References

No definition available.

+ Details

Name:	us-gaap_InventoryRealEstateHeldForSale
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfUnitsInRealEstateProperty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from sale of buildings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3179-108585

+ Details

Name:	us-gaap_ProceedsFromSaleOfBuildings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Name:	us-gaap_RealEstatePropertiesLineItems
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=63488584&loc=d3e20235-122688

+ Details

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

- Details

Name:	us-gaap_StatementGeographicalAxis=ess_PaloAltoCAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=us-gaap_ApartmentBuildingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=ess_EmeryvilleCAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ess_JeffersonatHollywoodMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupHeldforsaleNotDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Real Estate Investments - Sales of Real Estate Investments (Details) $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Jan. 31, 2016 USD ($)	Mar. 31, 2015 USD ($) community	Mar. 31, 2017 USD ($) unit	Dec. 31, 2017 USD ($) community unit	Dec. 31, 2016 USD ($) community unit	Dec. 31, 2015 USD ($) community unit
Real Estate Properties [Line Items]
Number of communities sold \| community				1	3	2
Number of units sold \| unit				270	323	848
Sales Price				$ 132,500	$ 80,800	$ 308,800
Gain on sale of properties				26,200	14,000	44,900
Gain on sale of real estate				26,200
Deferred tax expense on gain on sale of real estate and land				$ 0	4,410	$ 0
Palo Alto, CA [Member]
Real Estate Properties [Line Items]
Proceeds from sale of headquarters building	$ 18,000
Palo Alto, CA [Member] \| Apartment Building [Member]
Real Estate Properties [Line Items]
Gain on sale of corporate headquarters	$ 9,600
Emeryville, CA [Member]
Real Estate Properties [Line Items]
Number of communities sold \| community		2
Sales Price		$ 13,000
Gain on sale of properties		$ 2,400
Jefferson at Hollywood [Member]
Real Estate Properties [Line Items]
Number of units sold \| unit			270
Sales Price			$ 132,500
Essex Ownership Percentage			100.00%
Gain on sale of real estate			$ 26,200
Jefferson at Hollywood [Member] \| Apartment Building [Member]
Real Estate Properties [Line Items]
Carrying value of real estate assets held-for-sale					$ 102,000
Jefferson at Hollywood [Member] \| Apartment Building [Member] \| Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Real Estate Properties [Line Items]
Number of units in real estate property \| unit					270