Asset Acquisition Amount Paid To Acquire Joint Venture Partners Interests

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- Definition

Asset Acquisition, Recognized Identifiable Assets Acquired And Liabilities Assumed, Financial Liabilities

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Equity Method Investment, Number Of Properties

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- Definition

Preferred Equity In Joint Venture Annual Rate Of Return

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- Definition

Unconsolidated Joint Ventures Excess Profit Participation Percentage Forfeited

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- Definition

Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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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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The amount of capital contributed by the preferred partners.

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- 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.

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Investments in Unconsolidated Real Estate Ventures - Narrative (Details) $ in Thousands				9 Months Ended
	Jun. 19, 2018 USD ($) property	Apr. 26, 2018 USD ($) property	Feb. 02, 2018 USD ($)	Sep. 30, 2018 property	Apr. 27, 2018
WICNN JV LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores \| property	7			7
Initial contribution	$ 4,505
Equity method ownership (as a percent)	10.00%			10.00%
Preferred equity contribution	$ 22,734
Annual rate of return (as a percent)	8.00%
WCOT Self Storage LLC
Schedule of Equity Method Investments [Line Items]
Number of Stores \| property		14		0
Initial contribution		$ 115,797
Equity method ownership (as a percent)		95.00%		5.00%	100.00%
Liabilities assumed, loan		$ 87,500
Teachers REA II LLC
Schedule of Equity Method Investments [Line Items]
Financing distribution			$ 47,944
Minimum \| Teachers REA II LLC
Schedule of Equity Method Investments [Line Items]
Equity method ownership (as a percent)			40.00%
Unconsolidated joint ventures excess profit participation percentage forfeited			25.00%
Maximum \| Teachers REA II LLC
Schedule of Equity Method Investments [Line Items]
Equity method ownership (as a percent)			49.00%
Unconsolidated joint ventures excess profit participation percentage forfeited			34.00%