Note 2 - Reverse Stock Split (Details Textual)	Oct. 19, 2020 $ / shares shares	Jun. 30, 2021 $ / shares shares	Dec. 31, 2020 $ / shares shares	Oct. 18, 2020 shares
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares		$ 0.01	$ 0.01
Common Stock, Shares Authorized (in shares)		20,000,000	20,000,000
Common Stock, Shares, Outstanding, Ending Balance (in shares)		8,421,910	8,421,910
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	20
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares	$ 0.01
Common Stock, Shares Authorized (in shares)	20,000,000			400,000,000
Common Stock, Shares, Outstanding, Ending Balance (in shares)	8,421,910			168,069,305