DEBT - Company's Mortgage Notes (Details) - USD ($)			12 Months Ended
	Feb. 04, 2020	Jan. 31, 2020	Dec. 31, 2019	Dec. 31, 2023	Dec. 16, 2019	Dec. 31, 2018
Short-term Debt [Line Items]
Principal balance			$ 208,279,481
Plus: unamortized mortgage premium, net of discount			489,664
Less: unamortized deferred financing costs			(2,280,077)
Total			$ 206,489,068
Loans to assets ratio (as a percent)			60.00%
Accredo and Walgreens acquisitions
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			3.95%
Effective interest rate ( as a percent)			3.95%
Principal balance			$ 6,853,442			$ 6,996,469
Six Dollars General properties
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.69%
Effective interest rate ( as a percent)			4.69%
Principal balance			$ 3,819,264			3,885,334
Dana
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.56%
Effective interest rate ( as a percent)			4.56%
Principal balance			$ 4,551,250			4,632,398
Northrop Grumman
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.40%
Effective interest rate ( as a percent)			4.40%
Principal balance			$ 5,666,866			5,809,367
exp US Services
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.25%
Effective interest rate ( as a percent)			4.25%
Principal balance			$ 3,385,353			3,446,493
exp US Services | Treasury Bill Index
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			3.25%
Harley
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.25%
Effective interest rate ( as a percent)			4.25%
Principal balance			$ 6,748,029			6,868,254
Wyndham
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			4.34%
Principal balance			$ 5,716,200			5,820,600
Wyndham | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			2.05%
Williams Sonoma
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			4.34%
Principal balance			$ 4,530,600			4,615,800
Williams Sonoma | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			2.05%
Omnicare
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.36%
Effective interest rate ( as a percent)			4.36%
Principal balance			$ 4,273,552			4,349,963
EMCOR
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.35%
Effective interest rate ( as a percent)			4.35%
Principal balance			$ 2,862,484			2,911,577
Husqvarna
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.60%
Effective interest rate ( as a percent)			4.60%
Principal balance			$ 6,379,182			6,379,182
AvAir
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.84%
Effective interest rate ( as a percent)			4.84%
Principal balance			$ 14,575,000			14,575,000
AvAir | Minimum | Treasury Bill Index
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.60%
AvAir | Maximum | Treasury Bill Index
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			2.45%
3M
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			5.09%
Principal balance			$ 8,290,000			8,360,000
3M | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			2.25%
Cummins
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			5.16%
Principal balance			$ 8,458,600			8,530,000
Cummins | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			2.25%
24 Hour Fitness
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.64%
Effective interest rate ( as a percent)			4.64%
Principal balance			$ 6,283,898			8,900,000
Texas Health
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.00%
Effective interest rate ( as a percent)			4.00%
Principal balance			$ 4,400,000			4,842,500
Bon Secours
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			5.41%
Effective interest rate ( as a percent)			5.41%
Principal balance			$ 5,250,000			5,250,000
Costco
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.85%
Effective interest rate ( as a percent)			4.85%
Principal balance			$ 18,850,000			18,850,000
Taylor Fresh Farm property
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			3.85%
Effective interest rate ( as a percent)			3.85%
Principal balance			$ 12,350,000			0
Levins
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.74%
Principal balance			$ 2,079,793			0
Levins | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.93%
Island Pacific Supermarket
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.74%
Principal balance			$ 1,891,225			0
Island Pacific Supermarket | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.93%
Dollar General
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.38%
Principal balance			$ 2,324,338			0
Dollar General | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.48%
Rite Aid
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.25%
Principal balance			$ 3,659,338			0
Rite Aid | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.50%
PMI Preclinical
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.38%
Principal balance			$ 4,118,613			0
PMI Preclinical | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.48%
EcoThrift
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			2.96%
Principal balance			$ 2,639,237			0
EcoThrift | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.21%
GSA (MSHA)
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			3.00%
Principal balance			$ 1,796,361			0
GSA (MSHA) | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			1.25%
PreK San Antonio
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.25%
Effective interest rate ( as a percent)			4.25%
Principal balance			$ 5,140,343			0
Dinan Cars
Short-term Debt [Line Items]
Effective interest rate ( as a percent)			4.02%
Principal balance			$ 2,710,834			0
Dinan Cars | (LIBOR)
Short-term Debt [Line Items]
Basis spread on variable rate ( as a percent)			2.27%
Solar Turbines/Wood Group/ITW Rippey
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			3.35%
Effective interest rate ( as a percent)			3.35%
Principal balance			$ 9,434,692			0
Dollar General Big Spring
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.50%
Effective interest rate ( as a percent)			4.50%
Principal balance			$ 611,161			0
Gap
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.15%
Effective interest rate ( as a percent)			4.15%
Principal balance			$ 3,643,166			0
L-3 Communications
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.69%
Effective interest rate ( as a percent)			4.69%
Principal balance			$ 5,284,884			0
Sutter Health
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			4.50%
Effective interest rate ( as a percent)			4.50%
Principal balance			$ 14,161,776			0
Walgreens
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)			7.50%
Effective interest rate ( as a percent)			7.50%
Principal balance			$ 3,000,000			0
Mortgage Notes Payable
Short-term Debt [Line Items]
Principal balance			195,739,481			125,022,937
Plus: unamortized mortgage premium, net of discount			489,664			0
Less: unamortized deferred financing costs			(2,189,938)			(2,313,629)
Total			194,039,207			122,709,308
Face value			$ 195,739,481			$ 125,022,937
Mortgage Notes Payable | Texas Health
Short-term Debt [Line Items]
Face value					$ 4,400,000
Forecast | Husqvarna | Minimum | Treasury Bill Index
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)				4.60%
Forecast | Husqvarna | Maximum | Treasury Bill Index
Short-term Debt [Line Items]
Contractual Interest Rate (as a percent)				2.45%
Subsequent Event | Dinan Cars
Short-term Debt [Line Items]
Proceeds from lease payments		$ 783,182
Subsequent Event | Mortgage Notes Payable | Dinan Cars
Short-term Debt [Line Items]
Repayments of debt		650,000
Debt instrument, payment reserve		$ 133,182
Swap | Subsequent Event | Dinan Cars
Short-term Debt [Line Items]
Derivative, cost of hedge net of cash received	$ 47,000