Note 11 - Fair Value Accounting (Details Textual)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021 USD ($)
Derivative Liability, Current	$ 6,024,000	$ 5,292,000
Measurement Input, Risk Free Interest Rate [Member]
Derivative Liability, Measurement Input	2.38
Measurement Input, Price Volatility [Member]
Derivative Liability, Measurement Input	127.8
Measurement Input, Expected Term [Member]
Derivative Liability, Measurement Input	2.76
Measurement Input, Expected Dividend Rate [Member]
Derivative Liability, Measurement Input	0.040
Series D Preferred Stock Instrument [Member]
Derivative Liability, Current	$ 6,024,000	$ 5,292,000	$ 5,292,000
Series D Preferred Stock Instrument [Member] | Measurement Input, Expected Term [Member]
Derivative Liability, Measurement Input	2.76