Note 11 - Derivative Warrant Liabilities (Tables)
|12 Months Ended|
Mar. 31, 2020
|Schedule of Derivative Liabilities at Fair Value [Table Text Block]||
|Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]||
Tabular disclosure of input and valuation technique used to measure fair value and change in valuation approach and technique for each separate class of asset and liability measured on recurring and nonrecurring basis.
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef