Note 12 - Shareholders' Equity (Details Textual) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Preferred Stock, Shares Authorized (in shares)	250,000
Preferred Stock, No Par Value (in dollars per share)	$ 0
Preferred Stock, Shares Issued, Total (in shares)	0
Non-voting Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)	250,000
Preferred Stock, No Par Value (in dollars per share)	$ 0
Series A Non-voting Convertible Preferred Stock [Member]
Preferred Stock, Shares Authorized (in shares)	125,000	125,000
Preferred Stock, Shares Issued, Total (in shares)	0	0
Preferred Stock, Shares Outstanding, Ending Balance (in shares)	0	0
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.06	$ 0.06