Note 11 - Related Party Transactions (Details Textual) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Jul. 01, 2019	Jan. 01, 2019	Dec. 31, 2018
Due to Related Parties, Noncurrent, Total		$ 1,157,908		$ 1,157,908		$ 1,123,769
Due from Related Parties, Current, Total		0		0		100,000
Series C Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)	170,000
Proceeds from Issuance of Preferred Stock and Preference Stock	$ 1,500,000
Schwan Incorporated [Member]
Related Party Transaction, Amounts of Transaction				31,000	$ 2,700
Accounts Payable, Related Parties		0		0
John H Schwan [Member] | Promissory Note [Member]
Due to Related Parties, Noncurrent, Total									$ 997,019	$ 1,600,000
Repayments of Related Party Debt				0			$ 0
Interest Expense, Related Party		17,000	$ 16,000	34,000	$ 32,000
CTI Europe [Member]
Long-term Debt, Gross		0		0		9,000
Board of Directors Chairman [Member]
Due from Related Parties, Current, Total		$ 0		$ 0		100,000		$ 1,300,000
Note Receivable, Reserve						$ 1,277,000
LF International [Member] | Series C Preferred Stock [Member]
Stock Issued During Period, Shares, New Issues (in shares)	170,000
Proceeds from Issuance of Preferred Stock and Preference Stock	$ 1,500,000