Note 2 - Net Profits Interest Divestiture (Details Textual) - USD ($) $ in Millions |
12 Months Ended | |
---|---|---|
Dec. 31, 2020 |
Mar. 31, 2021 |
|
Net Profits Interests Divestiture, Consideration | $ 5.7 | |
Trade and Other Receivables [Member] | ||
Net Profits Interests Divestiture, Consideration, Holdbacks | $ 0.2 |