Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($)			3 Months Ended		9 Months Ended
	Nov. 09, 2021	Jul. 09, 2015	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)					0	0
Income Tax Expense (Benefit), Total			$ 0	$ 0	$ 0	$ 0
Stock Issued During Period, Shares, New Issues (in shares)		6,459,948
Percentage of Common Shares Owned by Investor		60.20%
Cash Equivalents, at Carrying Value, Total			0	0	0	0
Cash, Uninsured Amount			12,951,581		12,951,581		$ 331,385
Restricted Cash, Total			5,000,000	$ 0	5,000,000	0
Accounts Receivable, Allowance for Credit Loss, Current			$ 0		0		$ 0
Accounts Receivable, Allowance for Credit Loss, Writeoff					$ 0	$ 0
Number of Finite-Lived Intangible Assets			2		2
Impairment of Intangible Assets (Excluding Goodwill), Total					$ 0
Customer Base [Member]
Finite-Lived Intangible Asset, Useful Life (Year)					20 years
Trade Names [Member]
Finite-Lived Intangible Asset, Useful Life (Year)					3 years
Avenue Capital Loan [Member]
Debt Instrument, Face Amount			$ 15,000,000		$ 15,000,000
Debt Instrument, Interest Rate, Stated Percentage			10.99%		10.99%
Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months			$ 0		$ 0
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total			193,900,000		193,900,000
Operating Loss Carryforwards, Amount Subject to Expiration			140,600,000		140,600,000
Operating Loss Carryforwards, Amount Not Subject to Expiration			53,300,000		53,300,000
Tax Credit Carryforward, Amount			4,300,000		4,300,000
Operating Loss Carryforwards With Limited Ability to Utilize			124,800,000		124,800,000
Tax Credit Carryforwards With Limited Ability to Utilize			3,650,000		3,650,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total			112,200,000		112,200,000
Tax Credit Carryforward, Amount			300,000		300,000
Operating Loss Carryforwards With Limited Ability to Utilize			73,400,000		73,400,000
Tax Credit Carryforwards With Limited Ability to Utilize			$ 300,000		$ 300,000
The Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)			597,557		597,557
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)			536,089		536,089
Common Stock, Capital Shares Reserved for Future Issuance (in shares)			45,468		45,468
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)					10 years
The Plan [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	3,000,000
The ESPP [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)			925,000		925,000
Percentage of Common Stock Outstanding of Preceding Year					10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Limited Per Year (in shares)			100,000		100,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate			15.00%		15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount from Market Price, Offering Date					85.00%