REAL ESTATE INVESTMENTS - Portfolio Concentrations (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Real Estate [Line Items]
Net Carrying Value	$ 403,535,694	$ 224,648,345
AvAir, AZ
Real Estate [Line Items]
Total revenues	$ 2,670,159	$ 2,100,000
Concentration risk percentage	10.90%	19.90%
AvAir, AZ \| Percentage of Total Assets
Real Estate [Line Items]
Net Carrying Value	$ 0	$ 27,353,125
Concentration risk percentage	0.00%	17.40%
Northrop Grumman
Real Estate [Line Items]
Total revenues	$ 0	$ 1,162,274
Concentration risk percentage	0.00%	11.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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