COMMERCIAL LOAN AND MASTER LEASE INVESTMENTS - Summary of Commercial Loan Investments (Details) - USD ($)	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Mortgage Loans On Real Estate [Line Items]
Original Face Amount	$ 39,404,901
Current Face Amount	39,404,901	$ 34,570,000
Carrying Value	39,679,612	$ 34,625,173
LPGA Buyer Loan - Daytona Beach, FL
Mortgage Loans On Real Estate [Line Items]
Original Face Amount	2,070,000
Current Face Amount	2,070,000
Carrying Value	$ 1,860,455
Interest rate (as a percent)	7.50%
Master Tenant - Hialeah Lease Loan - Hialeah FL [Member]
Mortgage Loans On Real Estate [Line Items]
Original Face Amount	$ 21,084,901
Current Face Amount	21,084,901
Carrying Value	21,084,901
Carpenter Hotel-400 Josephine Street, Austin, TX
Mortgage Loans On Real Estate [Line Items]
Original Face Amount	16,250,000
Current Face Amount	16,250,000
Carrying Value	$ 16,734,256

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column B
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
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Amount, before allowance and fees, of loans and leases receivable. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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Amount of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G))
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