Investments in Unconsolidated Real Estate Ventures - Narrative (Details) $ in Thousands	1 Months Ended	6 Months Ended
May 31, 2019 USD ($) annex_site store joint_venture_partner	Jun. 30, 2019 USD ($) store
Schedule of Equity Method Investments [Line Items]
Contributions to joint ventures \| $		$ 54,779
ESS-NYFL JV LP
Schedule of Equity Method Investments [Line Items]
Number of joint venture partners \| joint_venture_partner	2
Contributions to joint ventures \| $	$ 13,936
Number of operating stores acquired \| store	11	16
Number of annex sites acquired \| annex_site	4
Equity method ownership percentage	16.00%	16.00%
Number of stores acquired at certificate of occupancy \| store		6

Contributions To Equity Method Investments, Including Noncash Amounts

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Number Of Annex Sites Acquired By Joint Venture

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Number Of Joint Venture Partners

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Number Of Real Estate Properties Acquired By Joint Ventures

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Number Of Stores Acquired At Issuance Of Certificate Of Occupancy

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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