REAL ESTATE INVESTMENTS - 2018 Acquisition Activity (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Real Estate [Line Items]
Payments to acquire and develop real estate	$ 176,660,507	$ 93,253,505
Acquisition costs		2,702,043
3M
Real Estate [Line Items]
Payments to acquire and develop real estate		15,701,697
Acquisition costs		456,000
Cummins
Real Estate [Line Items]
Payments to acquire and develop real estate		16,002,488
Acquisition costs		465,000
Northrop Grumman
Real Estate [Line Items]
Payments to acquire and develop real estate		329,410
Acquisition costs		9,000
24 Hour Fitness
Real Estate [Line Items]
Payments to acquire and develop real estate		12,658,311
Acquisition costs		366,000
Texas Health
Real Estate [Line Items]
Payments to acquire and develop real estate		7,689,924
Acquisition costs		222,750
Bon Secours
Real Estate [Line Items]
Payments to acquire and develop real estate		10,842,907
Acquisition costs		313,293
Costco
Real Estate [Line Items]
Payments to acquire and develop real estate		30,028,768
Acquisition costs		870,000
Land
Real Estate [Line Items]
Payments to acquire and develop real estate	45,649,596	19,247,622
Land | 3M
Real Estate [Line Items]
Payments to acquire and develop real estate		758,780
Land | Cummins
Real Estate [Line Items]
Payments to acquire and develop real estate		3,347,959
Land | Northrop Grumman
Real Estate [Line Items]
Payments to acquire and develop real estate		329,410
Land | 24 Hour Fitness
Real Estate [Line Items]
Payments to acquire and develop real estate		3,121,985
Land | Texas Health
Real Estate [Line Items]
Payments to acquire and develop real estate		1,827,914
Land | Bon Secours
Real Estate [Line Items]
Payments to acquire and develop real estate		1,658,659
Land | Costco
Real Estate [Line Items]
Payments to acquire and develop real estate		8,202,915
Building and Building Improvements
Real Estate [Line Items]
Payments to acquire and develop real estate	133,340,311	66,046,320
Building and Building Improvements | 3M
Real Estate [Line Items]
Payments to acquire and develop real estate		14,004,039
Building and Building Improvements | Cummins
Real Estate [Line Items]
Payments to acquire and develop real estate		11,117,531
Building and Building Improvements | Northrop Grumman
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Building and Building Improvements | 24 Hour Fitness
Real Estate [Line Items]
Payments to acquire and develop real estate		8,331,352
Building and Building Improvements | Texas Health
Real Estate [Line Items]
Payments to acquire and develop real estate		5,148,789
Building and Building Improvements | Bon Secours
Real Estate [Line Items]
Payments to acquire and develop real estate		8,383,892
Building and Building Improvements | Costco
Real Estate [Line Items]
Payments to acquire and develop real estate		19,060,717
Tenant Origination and Absorption Costs
Real Estate [Line Items]
Payments to acquire and develop real estate	9,548,791	9,377,046
Tenant Origination and Absorption Costs | 3M
Real Estate [Line Items]
Payments to acquire and develop real estate		2,356,361
Tenant Origination and Absorption Costs | Cummins
Real Estate [Line Items]
Payments to acquire and develop real estate		1,536,998
Tenant Origination and Absorption Costs | Northrop Grumman
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Tenant Origination and Absorption Costs | 24 Hour Fitness
Real Estate [Line Items]
Payments to acquire and develop real estate		1,204,974
Tenant Origination and Absorption Costs | Texas Health
Real Estate [Line Items]
Payments to acquire and develop real estate		713,221
Tenant Origination and Absorption Costs | Bon Secours
Real Estate [Line Items]
Payments to acquire and develop real estate		800,356
Tenant Origination and Absorption Costs | Costco
Real Estate [Line Items]
Payments to acquire and develop real estate		2,765,136
Above Market Leases
Real Estate [Line Items]
Payments to acquire and develop real estate	764,531	0
Above Market Leases | 3M
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | Cummins
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | Northrop Grumman
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | 24 Hour Fitness
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | Texas Health
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | Bon Secours
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Above Market Leases | Costco
Real Estate [Line Items]
Payments to acquire and develop real estate		0
Below Market Leases
Real Estate [Line Items]
Payments to acquire real estate below market leases	$ (12,642,722)	(1,417,483)
Below Market Leases | 3M
Real Estate [Line Items]
Payments to acquire real estate below market leases		(1,417,483)
Below Market Leases | Cummins
Real Estate [Line Items]
Payments to acquire real estate below market leases		0
Below Market Leases | Northrop Grumman
Real Estate [Line Items]
Payments to acquire real estate below market leases		0
Below Market Leases | 24 Hour Fitness
Real Estate [Line Items]
Payments to acquire real estate below market leases		0
Below Market Leases | Texas Health
Real Estate [Line Items]
Payments to acquire real estate below market leases		0
Below Market Leases | Bon Secours
Real Estate [Line Items]
Payments to acquire real estate below market leases		0
Below Market Leases | Costco
Real Estate [Line Items]
Payments to acquire real estate below market leases		$ 0