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Note 14 - Purchase of Noncontrolling Interest (Details Textual) - BNSC [Member] - USD ($) $ in Millions		12 Months Ended
	Oct. 18, 2021	Dec. 31, 2020	Jan. 31, 2022
Academy Bank, N.A. [Member] \| Manager Loan [Member]
Long-term Debt, Total			$ 13.2
Debt Instrument, Interest Rate, Stated Percentage	5.75%
BHCMC, LLC [Member]
Business Combination, Step Acquisition, Equity Interest in Acquiree, including Subsequent Acquisition, Percentage, Total			100.00%
Business Combination, Consideration Transferred, Total	$ 16.4
BHCMC, LLC [Member] \| Academy Bank, N.A. [Member] \| Manager Loan [Member]
Business Combination, Consideration Transferred, Liabilities Incurred	7.0	$ 35.0
BHCMC, LLC [Member] \| Commercial Loan [Member] \| Academy Bank, N.A. [Member]
Business Combination, Consideration Transferred, Liabilities Incurred	$ 8.0