Real Estate Assets - Additional Information (Details) - Millbrook, NY - ft²	3 Months Ended
Jun. 30, 2019	Mar. 31, 2019
Real Estate Properties [Line Items]
Estimate for expansion relating to construction cost		As of March 31, 2019, development costs for this project has been capitalized and are reflected in real estate assets, net on the Company’s consolidated balance sheet.
Scenario Forecast
Real Estate Properties [Line Items]
Gross square feet of traditional drive-up storage units and all-climate-controlled units	16,500

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.

No definition available.

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