Asset Acquisition Amount Paid To Acquire Joint Venture Partners Interests

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- Definition

Represents the period of amortization of the excess purchase price of equity investments over its original basis included in equity earnings.

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No definition available.

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- Definition

Equity Method Investment, Ownership Percentage Sold

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- Definition

Net carrying amount of properties distributed.

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- Definition

Number of acquired stores.

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No definition available.

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- Definition

Represents the number of real estate properties acquired.

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No definition available.

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- Definition

Number of transferred stores.

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- Definition

Number of Stores Owned

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No definition available.

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- Definition

Payments To Acquire Assets, Gross

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No definition available.

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- Definition

Real estate property acquisition, assets acquired.

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No definition available.

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- Definition

Unconsolidated Joint Ventures Excess Profit Participation Percentage Forfeited

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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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- Definition

Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

+ References

No definition available.

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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- Definition

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

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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of the entity's equity method investment which has been sold.

+ References

No definition available.

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- Definition

The amount of debt that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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.

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No definition available.

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Investments in Unconsolidated Real Estate Ventures - Additional Information (Details) $ in Thousands					3 Months Ended								12 Months Ended
	Apr. 30, 2018 USD ($) store	Nov. 17, 2016 USD ($) store	Sep. 16, 2016 USD ($) store	Feb. 02, 2016 USD ($) store	Dec. 31, 2018 USD ($) store	Sep. 30, 2018 USD ($) store	Jun. 30, 2018 USD ($) store	Mar. 31, 2018 USD ($) store	Dec. 31, 2017 USD ($) store	Sep. 30, 2017 USD ($) store	Jun. 30, 2017 USD ($) store	Mar. 31, 2017 USD ($) store	Dec. 31, 2018 USD ($) store	Dec. 31, 2017 USD ($) store	Apr. 25, 2016	Apr. 24, 2016
Schedule of Equity Method Investments [Line Items]
Cash paid to acquire properties					$ 74,868	$ 71,989	$ 148,650	$ 70,171	$ 502,845	$ 29,919	$ 16,608	$ 25,541	$ 365,678	$ 574,913
Loan assumed					$ 0	$ 0	$ 87,500	$ 0	$ 14,592	$ 0	$ 9,463	$ 0	$ 87,500	$ 24,055
Number of stores acquired \| store					6	6	17	5	37	4	3	2	34	46
Amortization amount of excess purchase price included in equity earnings					$ 27,867								$ 27,867
Amortization period of excess purchase price included in equity earnings													40 years
Properties acquired September 2016
Schedule of Equity Method Investments [Line Items]
Fair value of stores purchased			$ 248,530
WCOT Self Storage LLC
Schedule of Equity Method Investments [Line Items]
Cash paid to acquire properties	$ 115,797
Loan assumed	$ 87,500
Number of stores acquired \| store	14
Equity ownership %					5.00%								5.00%
ESS WCOT LLC
Schedule of Equity Method Investments [Line Items]
Number of acquired stores \| store		11
Equity ownership %		5.00%
Percentage interests acquired		95.00%
Net carrying amount of properties distributed		$ 68,814
Payment to acquire joint venture interests		$ 153,304
Ownership percentage after transaction		100.00%
Fair value of investment prior to acquisition of additional interest		$ 8,119
Gain recorded as a result of remeasuring fair value of existing equity interest		4,651
Fair value of stores purchased		$ 161,072
ESS PRISA II LLC
Schedule of Equity Method Investments [Line Items]
Number of acquired stores \| store			23
Equity ownership %			4.40%
Number of stores owned \| store														42
Ownership percentage sold			4.42%
Carrying value of investment prior to acquisition			$ 3,912
Realized gain on sale			30,846
ESS PRISA II LLC \| Prudential Real Estate and Affiliates
Schedule of Equity Method Investments [Line Items]
Proceeds from sale of interest			34,758
Extra Space Properties 131 LLC
Schedule of Equity Method Investments [Line Items]
Net carrying amount of properties distributed			$ 4,326
Ownership percentage after transaction			100.00%
Fair value of investment prior to acquisition of additional interest			$ 10,988
Gain recorded as a result of remeasuring fair value of existing equity interest			$ 6,778
Number of transferred stores \| store			23
Extra Space Properties 131 LLC \| Prudential Real Estate and Affiliates
Schedule of Equity Method Investments [Line Items]
Percentage interests acquired			95.60%
Payment to acquire joint venture interests			$ 238,679
ESS PRISA LLC and ESS PRISA II LLC
Schedule of Equity Method Investments [Line Items]
Unconsolidated joint ventures excess profit participation percentage forfeited															17.00%
ESS PRISA LLC
Schedule of Equity Method Investments [Line Items]
Equity ownership %															4.00%	2.00%
ESS Prisa II LLC
Schedule of Equity Method Investments [Line Items]
Equity ownership %															4.40%	2.00%
VRS Self Storage LLC
Schedule of Equity Method Investments [Line Items]
Number of acquired stores \| store				6
Equity ownership %				45.00%
Extra Space Properties 122 LLC
Schedule of Equity Method Investments [Line Items]
Number of acquired stores \| store				6
Net carrying amount of properties distributed				$ 17,261
Ownership percentage after transaction				100.00%
Fair value of investment prior to acquisition of additional interest				$ 44,184
Gain recorded as a result of remeasuring fair value of existing equity interest				26,923
Fair value of stores purchased				$ 98,082
Number of transferred stores \| store				6
Extra Space Properties 122 LLC \| Prudential Real Estate and Affiliates
Schedule of Equity Method Investments [Line Items]
Percentage interests acquired				55.00%
Payment to acquire joint venture interests				$ 53,940