Note 10 - Leasing Arrangements (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment, Net	$ 16,059,000	$ 15,878,000
Operating Lease, Expense	34,000	49,000
Office and Equipment [Member]
Operating Lease, Payments	23,000	53,000
Asset Leased to Others [Member]
Property, Plant and Equipment, Net	$ 10,300,000	$ 10,100,000