LONG-TERM DEBT - Outstanding Indebtedness (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) property	Dec. 31, 2018	Apr. 30, 2016 USD ($)	Mar. 11, 2015 USD ($)
Long-term debt
Face Value of Debt	$ 288,729,722
Interest Rate Swap
Long-term debt
Fixed interest rate through use of derivative (as a percent)	3.17%
Credit Facility
Long-term debt
Face Value of Debt	$ 159,845,349
Credit Facility | LIBOR | Minimum
Long-term debt
Margin added to variable rate basis (as a percent)	1.35%
Credit Facility | LIBOR | Maximum
Long-term debt
Margin added to variable rate basis (as a percent)	1.95%
Wells Fargo Mortgage Note Payable Originated September 30, 2014
Long-term debt
Face Value of Debt	$ 30,000,000
Stated interest rate (as a percent)	4.33%
Number of income properties securing debt | property	6
Period of fixed interest rate	10 years
Period of interest only payments	10 years
Period after which cash flows generated by underlying income properties must be used to pay down principal balance	10 years
Period to when loan is pre-payable	10 years
Wells Fargo Mortgage Note Payable Originated April 15, 2016
Long-term debt
Face Value of Debt	$ 23,884,373		$ 25,000,000
Period of interest only payments	2 years
Period of amortization for principal payments	25 years
Term of loan	5 years
Wells Fargo Mortgage Note Payable Originated April 15, 2016 | LIBOR
Long-term debt
Margin added to variable rate basis (as a percent)	1.90%
4.50% Convertible Senior Notes due 2020
Long-term debt
Face Value of Debt	$ 75,000,000			$ 75,000,000
Stated interest rate (as a percent)	4.50%	4.50%