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Note 6 - Purchase of Noncontrolling Interest (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Oct. 18, 2021	Dec. 31, 2020	Apr. 30, 2022	Jan. 31, 2022	Apr. 30, 2021
Long-Term Debt, Total			$ 48,576		$ 45,788
BNSC [Member] \| Academy Bank, N.A. [Member] \| Manager Loan [Member]
Long-Term Debt, Total			$ 12,700
Debt Instrument, Interest Rate, Stated Percentage	5.75%
BHCMC, LLC [Member] \| BNSC [Member]
Business Combination, Step Acquisition, Equity Interest in Acquiree, including Subsequent Acquisition, Percentage, Total				100.00%
Business Combination, Consideration Transferred, Total	$ 16,400
BHCMC, LLC [Member] \| BNSC [Member] \| Academy Bank, N.A. [Member] \| Manager Loan [Member]
Business Combination, Consideration Transferred, Liabilities Incurred	7,000	$ 35,000
BHCMC, LLC [Member] \| BNSC [Member] \| Commercial Loan [Member] \| Academy Bank, N.A. [Member]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 8,000