Note 9 - Related Party Transactions (Details Textual) - John H Schwan [Member] - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Due to Related Parties, Total	$ 1,200,000		$ 1,200,000
Repayments of Related Party Debt	0
Interest Expense, Related Party	$ 18,000	$ 16,000

Carrying amount as of the balance sheet date of obligations due all related parties.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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+ Details