Number of mortgage loans 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.

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BUSINESS SEGMENT DATA - Description (Details)	3 Months Ended								12 Months Ended
BUSINESS SEGMENT DATA - Description (Details)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) segment loan	Dec. 31, 2018 USD ($) segment loan	Dec. 31, 2017 USD ($)
Business segment data
Number of operating segment \| segment									4	4
Assets	$ 703,286,203				$ 556,329,872				$ 703,286,203	$ 556,329,872
Depreciation and Amortization	4,089,568	$ 4,286,836	$ 4,074,587	$ 3,346,287	4,452,647	$ 3,756,507	$ 3,755,546	$ 3,796,823	15,797,278	15,761,523	$ 12,314,700
Income Properties
Business segment data
Assets	464,285,272				492,093,615				464,285,272	492,093,615
Depreciation and Amortization									15,774,228	15,728,095	12,272,265
Management Services
Business segment data
Assets	$ 0				0				0	0
Depreciation and Amortization									0	0	0
Capital Expenditures									$ 0	0	$ 0
Golf Operations
Business segment data
Assets					$ 4,462,477					$ 4,462,477
Commercial loans
Business segment data
Mortgage Loans on Real Estate, Number of Loans \| loan										0
Product concentration \| Identifiable assets \| Income Properties
Business segment data
Percentage of total									66.00%	88.50%
Product concentration \| Consolidated revenues \| Income Properties
Business segment data
Percentage of total									93.40%	91.80%	81.30%
Fixed–rate mezzanine \| Commercial loans
Business segment data
Mortgage Loans on Real Estate, Number of Loans \| loan									3