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)	Mar. 31, 2020 USD ($) segment loan	Mar. 31, 2019 USD ($) loan	Dec. 31, 2019 USD ($)
Business segment data
Number of operating segment \| segment	4
Assets	$ 717,035,731		$ 703,286,203
Depreciation and Amortization	4,552,471	$ 3,346,287
Capital Expenditures	144,751,728	930,575
Income Properties
Business segment data
Assets	586,557,285		464,285,272
Depreciation and Amortization	4,547,421	$ 3,339,856
Management Services
Business segment data
Assets	0		0
Depreciation and Amortization	0		0
Capital Expenditures	0		0
Golf Operations
Business segment data
Assets	$ 833,372		$ 833,167
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	81.80%		66.00%
Product concentration \| Consolidated revenues \| Income Properties
Business segment data
Percentage of total	85.70%		75.20%
Fixed–rate mezzanine \| Commercial loans
Business segment data
Mortgage Loans on Real Estate, Number of Loans \| loan	5