Note 2 - Significant Accounting Policies (Details Textual)	3 Months Ended
	Mar. 31, 2021 USD ($)		Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)
Amortization of above and below Market Leases	$ 1,000			$ 30,000
Amortization of Intangible Assets, Total	100,000			130,000
Deferred Costs, Total	1,500,000			1,900,000
Operating Lease, Initial Direct Cost Expense, over Term	86,000			99,000
Depreciation, Total	1,400,000			1,600,000
Cash Equivalents, at Carrying Value, Total	7,000,000.0		$ 11,500,000
Restricted Cash, Total	$ 4,000,000.0		4,200,000
Number of Real Estate Properties Held for Sale	3
Amortization of Debt Issuance Costs	$ 261,779			363,183
Real Estate Investment Property and Lease Intangibles, Net	145,348,000
Impairment of Real Estate	300,000			0
Series B Preferred Stock [Member]
Unamortized Deferred Stock Costs	100,000		100,000
Mortgage Notes [Member]
Debt Issuance Costs, Net, Total	900,000		800,000
Amortization of Debt Issuance Costs	1,200,000			1,600,000
Notes Payable to Banks [Member] | Polar Multi-Strategy Master Fund [Member]
Debt Issuance Costs, Net, Total			200,000
Amortization of Debt Issuance Costs	$ 200,000			$ 300,000
Executive Park [Member]
Number of Real Estate Properties Held for Sale	3
Model Home [Member]
Number of Real Estate Properties Held for Sale	16
Highland Court [Member]
Real Estate Investment Property and Lease Intangibles, Net	$ 10,218,000	[1]	10,500,000
Impairment of Real Estate			300,000
Highland Court [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Disposal Group, Including Discontinued Operation, Consideration			$ 10,200,000
Building and Building Improvements [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	39 years
Maximum [Member]
Amortization of Value In Place Leases (Year)	10 years
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	5 years
Maximum [Member] | Leasehold Improvements [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	10 years
Maximum [Member] | Furniture and Fixtures [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	5 years
Minimum [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	1 year
Minimum [Member] | Leasehold Improvements [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	1 year
Minimum [Member] | Furniture and Fixtures [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)	4 years

[1] This property is held for sale as of March 31, 2021.