REVENUE RECOGNITION - Timing of Revenue Recognition (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues
Revenue from contract with customer, including assessed tax									$ 852,000	$ 2,966,000	$ 5,191,000
Lease revenue									41,956,000	40,076,000	31,407,000
Over Lease Term									42,453,000	40,888,000	32,234,000
Commercial Loan Investment Related Revenue									1,829,000	616,000	2,053,000
Total Revenues	$ 11,963,117	$ 11,329,979	$ 10,688,831	$ 10,959,319	$ 12,040,174	$ 10,443,476	$ 10,805,062	$ 10,369,176	44,941,246	43,657,888	38,650,570
Asset/Good Transferred at a Point in Time
Revenues
Revenue from contract with customer, including assessed tax									254,000	2,009,000	4,335,000
Services Transferred Over Time
Revenues
Revenue from contract with customer, including assessed tax									405,000	145,000	29,000
Income Properties
Revenues
Over Lease Term									41,855,000	39,931,000	31,378,000
Total Revenues	10,594,870	10,260,831	10,375,295	10,724,418	11,728,550	9,360,155	9,781,299	9,205,727	41,955,414	40,075,731	31,406,930
Income Properties | Services Transferred Over Time
Revenues
Revenue from contract with customer, including assessed tax									101,000	145,000	29,000
Management Services
Revenues
Total Revenues	304,553								304,553
Management Services | Services Transferred Over Time
Revenues
Revenue from contract with customer, including assessed tax									304,000
Commercial Loan Investments
Revenues
Commercial Loan Investment Related Revenue									1,829,000	616,000	2,053,000
Total Revenues	920,691	855,559	52,765			41,262	273,467	300,999	1,829,015	615,728	2,052,689
Real Estate Operations
Revenues
Over Lease Term									598,000	957,000	856,000
Total Revenues	$ 143,003	$ 213,589	$ 260,771	$ 234,901	$ 311,624	$ 1,042,059	$ 750,296	$ 862,450	852,264	2,966,429	5,190,951
Real Estate Operations | Asset/Good Transferred at a Point in Time
Revenues
Revenue from contract with customer, including assessed tax									$ 254,000	$ 2,009,000	$ 4,335,000