REAL ESTATE INVESTMENTS - Schedule of Real Estate Properties (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Real Estate [Line Items]
Land, Buildings and Improvements	$ 396,680,878
Tenant origination and absorption costs	27,266,610	$ 17,717,819
Accumulated Depreciation and Amortization	(20,411,794)	(10,563,664)	$ (3,574,739)
Total investments in real estate property, net	403,535,694	$ 224,648,345
Office | Accredo Health
Real Estate [Line Items]
Land, Buildings and Improvements	9,855,847
Tenant origination and absorption costs	1,053,637
Accumulated Depreciation and Amortization	(1,754,846)
Total investments in real estate property, net	9,154,638
Office | Northrop Grumman
Real Estate [Line Items]
Land, Buildings and Improvements	12,382,991
Tenant origination and absorption costs	1,341,199
Accumulated Depreciation and Amortization	(2,185,956)
Total investments in real estate property, net	11,538,234
Office | exp US Services
Real Estate [Line Items]
Land, Buildings and Improvements	6,056,668
Tenant origination and absorption costs	388,248
Accumulated Depreciation and Amortization	(609,311)
Total investments in real estate property, net	5,835,605
Office | Wyndham
Real Estate [Line Items]
Land, Buildings and Improvements	10,406,483
Tenant origination and absorption costs	669,232
Accumulated Depreciation and Amortization	(815,730)
Total investments in real estate property, net	10,259,985
Office | Williams Sonoma
Real Estate [Line Items]
Land, Buildings and Improvements	8,079,612
Tenant origination and absorption costs	550,486
Accumulated Depreciation and Amortization	(746,900)
Total investments in real estate property, net	7,883,198
Office | EMCOR
Real Estate [Line Items]
Land, Buildings and Improvements	5,960,610
Tenant origination and absorption costs	463,488
Accumulated Depreciation and Amortization	(424,764)
Total investments in real estate property, net	5,999,334
Office | Cummins
Real Estate [Line Items]
Land, Buildings and Improvements	14,465,491
Tenant origination and absorption costs	1,536,998
Accumulated Depreciation and Amortization	(1,357,376)
Total investments in real estate property, net	14,645,113
Office | Texas Health
Real Estate [Line Items]
Land, Buildings and Improvements	6,976,703
Tenant origination and absorption costs	713,221
Accumulated Depreciation and Amortization	(384,029)
Total investments in real estate property, net	7,305,895
Office | Bon Secours
Real Estate [Line Items]
Land, Buildings and Improvements	10,042,551
Tenant origination and absorption costs	800,356
Accumulated Depreciation and Amortization	(526,238)
Total investments in real estate property, net	10,316,669
Office | PMI Preclinical
Real Estate [Line Items]
Land, Buildings and Improvements	9,672,174
Tenant origination and absorption costs	408,225
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	10,080,399
Office | GSA (MSHA)
Real Estate [Line Items]
Land, Buildings and Improvements	3,112,076
Tenant origination and absorption costs	243,307
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	3,355,383
Office | Solar Turbines
Real Estate [Line Items]
Land, Buildings and Improvements	7,133,241
Tenant origination and absorption costs	284,026
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	7,417,267
Office | Wood Group
Real Estate [Line Items]
Land, Buildings and Improvements	9,731,220
Tenant origination and absorption costs	392,955
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	10,124,175
Office | Gap
Real Estate [Line Items]
Land, Buildings and Improvements	8,378,276
Tenant origination and absorption costs	360,377
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	8,738,653
Office | L-3 Communications
Real Estate [Line Items]
Land, Buildings and Improvements	11,631,857
Tenant origination and absorption costs	454,035
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	12,085,892
Office | Sutter Health
Real Estate [Line Items]
Land, Buildings and Improvements	29,555,055
Tenant origination and absorption costs	1,616,610
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	31,171,665
Retail | Walgreens, Stockbridge, GA
Real Estate [Line Items]
Land, Buildings and Improvements	4,147,948
Tenant origination and absorption costs	705,423
Accumulated Depreciation and Amortization	(1,175,073)
Total investments in real estate property, net	3,678,298
Retail | Dollar General, Litchfield
Real Estate [Line Items]
Land, Buildings and Improvements	1,281,812
Tenant origination and absorption costs	116,302
Accumulated Depreciation and Amortization	(125,762)
Total investments in real estate property, net	1,272,352
Retail | Dollar General, Wilton
Real Estate [Line Items]
Land, Buildings and Improvements	1,543,776
Tenant origination and absorption costs	140,653
Accumulated Depreciation and Amortization	(160,948)
Total investments in real estate property, net	1,523,481
Retail | Dollar General, Thompsontown
Real Estate [Line Items]
Land, Buildings and Improvements	1,199,860
Tenant origination and absorption costs	106,730
Accumulated Depreciation and Amortization	(120,834)
Total investments in real estate property, net	1,185,756
Retail | Dollar General, Mt. Gilead
Real Estate [Line Items]
Land, Buildings and Improvements	1,174,188
Tenant origination and absorption costs	111,847
Accumulated Depreciation and Amortization	(115,853)
Total investments in real estate property, net	1,170,182
Retail | Dollar General, Lakeside
Real Estate [Line Items]
Land, Buildings and Improvements	1,112,872
Tenant origination and absorption costs	100,857
Accumulated Depreciation and Amortization	(118,901)
Total investments in real estate property, net	1,094,828
Retail | Dollar General, Castalia
Real Estate [Line Items]
Land, Buildings and Improvements	1,102,086
Tenant origination and absorption costs	86,408
Accumulated Depreciation and Amortization	(115,524)
Total investments in real estate property, net	1,072,970
Retail | Harley
Real Estate [Line Items]
Land, Buildings and Improvements	13,178,288
Tenant origination and absorption costs	0
Accumulated Depreciation and Amortization	(907,230)
Total investments in real estate property, net	12,271,058
Retail | 24 Hour Fitness
Real Estate [Line Items]
Land, Buildings and Improvements	11,484,784
Tenant origination and absorption costs	1,204,973
Accumulated Depreciation and Amortization	(653,647)
Total investments in real estate property, net	12,036,110
Retail | Costco
Real Estate [Line Items]
Land, Buildings and Improvements	27,292,418
Tenant origination and absorption costs	2,765,136
Accumulated Depreciation and Amortization	(1,352,612)
Total investments in real estate property, net	28,704,942
Retail | Chevron Gas Station, San Jose
Real Estate [Line Items]
Land, Buildings and Improvements	4,054,759
Tenant origination and absorption costs	145,577
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	4,200,336
Retail | Chevron Gas Station, Roseville
Real Estate [Line Items]
Land, Buildings and Improvements	3,648,571
Tenant origination and absorption costs	136,415
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	3,784,986
Retail | Island Pacific Supermarket
Real Estate [Line Items]
Land, Buildings and Improvements	2,560,311
Tenant origination and absorption costs	197,495
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	2,757,806
Retail | Dollar General
Real Estate [Line Items]
Land, Buildings and Improvements	4,899,714
Tenant origination and absorption costs	261,630
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	5,161,344
Retail | Rite Aid
Real Estate [Line Items]
Land, Buildings and Improvements	6,842,089
Tenant origination and absorption costs	420,441
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	7,262,530
Retail | EcoThrift
Real Estate [Line Items]
Land, Buildings and Improvements	5,550,226
Tenant origination and absorption costs	273,846
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	5,824,072
Retail | PreK Education
Real Estate [Line Items]
Land, Buildings and Improvements	12,447,287
Tenant origination and absorption costs	447,927
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	12,895,214
Retail | Dollar Tree
Real Estate [Line Items]
Land, Buildings and Improvements	1,320,367
Tenant origination and absorption costs	73,298
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	1,393,665
Retail | Dollar General Big Spring
Real Estate [Line Items]
Land, Buildings and Improvements	1,281,683
Tenant origination and absorption costs	76,351
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	1,358,034
Retail | Walgreens, Santa Maria
Real Estate [Line Items]
Land, Buildings and Improvements	5,223,442
Tenant origination and absorption costs	335,945
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	5,559,387
Industrial | Dana
Real Estate [Line Items]
Land, Buildings and Improvements	8,392,906
Tenant origination and absorption costs	1,210,874
Accumulated Depreciation and Amortization	(1,492,171)
Total investments in real estate property, net	8,111,609
Industrial | Omnicare
Real Estate [Line Items]
Land, Buildings and Improvements	7,262,747
Tenant origination and absorption costs	281,442
Accumulated Depreciation and Amortization	(587,875)
Total investments in real estate property, net	6,956,314
Industrial | Husqvarna
Real Estate [Line Items]
Land, Buildings and Improvements	11,840,200
Tenant origination and absorption costs	1,013,948
Accumulated Depreciation and Amortization	(756,557)
Total investments in real estate property, net	12,097,591
Industrial | AvAir
Real Estate [Line Items]
Land, Buildings and Improvements	27,357,900
Tenant origination and absorption costs	0
Accumulated Depreciation and Amortization	(1,417,062)
Total investments in real estate property, net	25,940,838
Industrial | 3M
Real Estate [Line Items]
Land, Buildings and Improvements	14,762,819
Tenant origination and absorption costs	2,356,361
Accumulated Depreciation and Amortization	(2,231,246)
Total investments in real estate property, net	14,887,934
Industrial | Taylor Fresh Foods
Real Estate [Line Items]
Land, Buildings and Improvements	34,194,370
Tenant origination and absorption costs	2,894,017
Accumulated Depreciation and Amortization	(275,349)
Total investments in real estate property, net	36,813,038
Industrial | Levins
Real Estate [Line Items]
Land, Buildings and Improvements	4,429,390
Tenant origination and absorption costs	221,927
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	4,651,317
Industrial | Dinan Cars
Real Estate [Line Items]
Land, Buildings and Improvements	6,252,657
Tenant origination and absorption costs	0
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	6,252,657
Industrial | ITW Rippey
Real Estate [Line Items]
Land, Buildings and Improvements	7,071,143
Tenant origination and absorption costs	304,387
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	7,375,530
Land | Northrop Grumman
Real Estate [Line Items]
Land, Buildings and Improvements	329,410
Tenant origination and absorption costs	0
Accumulated Depreciation and Amortization	0
Total investments in real estate property, net	$ 329,410