Note 14 - Net Income Per Common Share (Details Textual)		3 Months Ended	9 Months Ended
Mar. 05, 2021	Sep. 30, 2021	Sep. 30, 2021
The 2026 Notes and the 2028 Notes [Member]
Debt Instrument, Convertible, Conversion Ratio	0.4394	0.4394	0.4394

Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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