Note 12 - Related Party Transaction (Details Textual) - USD ($)	1 Months Ended	3 Months Ended
	Sep. 30, 2020	Apr. 30, 2023	Apr. 30, 2022	Feb. 02, 2023	Jan. 31, 2023
Preferred Stock, Par or Stated Value Per Share (in dollars per share)		$ 1.00			$ 1.00
Common Stock, Par or Stated Value Per Share (in dollars per share)		$ 0.01			$ 0.01
The Loan [Member]
Debt Instrument, Fee Amount				$ 50,000
Second ATM Offering Program [Member] | Common Stock [Member] | Non-executive Chairman [Member]
Stock Issued During Period, Shares, New Issues (in shares)		0	0
Ladenburg Thalmann and Co. Inc. [Member] | First ATM Offering Program [Member] | Common Stock [Member]
Equity Offering, Maximum Shares to be Issued (in shares)	5,000,000
Common Stock, Par or Stated Value Per Share (in dollars per share)	$ 0.01
Ladenburg Thalmann and Co. Inc. [Member] | Series A Preferred Stock [Member] | First ATM Offering Program [Member]
Equity Offering, Maximum Shares to be Issued (in shares)	500,000
Preferred Stock, Dividend Rate, Percentage	9.00%
Preferred Stock, Par or Stated Value Per Share (in dollars per share)	$ 1.00
Equity Offering, Distribution Compensation, Percentage of Gross Proceeds	2.00%
Ladenburg Thalmann and Co. Inc. [Member] | Series A Preferred Stock [Member] | Second ATM Offering Program [Member]
Stock Issued During Period, Shares, New Issues (in shares)		0	0