Note 1 - The Company (Details Textual)		12 Months Ended
	Sep. 01, 2015 USD ($)	Dec. 31, 2019 USD ($) ft² a
Flowerfield Industrial Park [Member]
Area of Real Estate Property | ft²		127,000
Multi-Tenant Industrial Park [Member]
Area of Real Estate Property		10
St. James, New York [Member] | Controlled by Parent Company [Member]
Area of Real Estate Property		68
Flowerfield Complex in Smithtown, New York [Member]
Area of Real Estate Property		62
Cortlandt Manor Medical Center [Member]
Area of Real Estate Property | ft²		34,000
Area of Land		13.8
The Corporation [Member]
Maximum Value of Asset to Effect Dissolution | $	$ 1,000,000	$ 1,000,000