Note 7 - Debt (Details Textual) $ in Thousands	Jan. 31, 2020 USD ($)
Line of Credit Facility, Maximum Borrowing Capacity	$ 5,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 5,000
Notes Collateralized by Aircraft Security Agreements, Due January 2023 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	6.25%
Notes Payable, Total	$ 1,843
Note Collateralized by Real Estate Due June 2024 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	6.25%
Notes Payable, Total	$ 229
Note Collateralized by Equipment Due April 2022 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Notes Payable, Total	$ 47
Note Collateralized by BNSC's Assets and Compensation due under State Management Contract Due May 2020 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	4.89%
Notes Payable, Total	$ 411

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Contractual interest rate for funds borrowed, under the debt agreement.

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-SubTopic 10
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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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