Note 9 - Net Loss Per Share (Details Textual) - $ / shares shares in Millions |
3 Months Ended | 12 Months Ended | |
---|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
Dec. 31, 2015 |
|
Securities Excluded from Computation of Earnings Per Share Amount, Performance Conditions (in shares) | 2.6 | 2.8 | |
Sale of Stock, Price Per Share (in dollars per share) | $ 17.50 | ||
Number of Trading Days of Share Price (Day) | 20 days | ||
Total Number of Trading Days Considered (Day) | 30 days | ||
IPO Warrants [Member] | |||
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ 11.50 | ||
Class of Warrant or Right, Redemption Price of Warrant or Right (in dollars per share) | $ 0.01 | ||
Class of Warrant or Right, Number of Days Notice to Redeem (Day) | 30 days |