Note 6 - Debt (Details Textual) $ in Thousands	Oct. 31, 2018 USD ($)
Line of Credit Facility, Maximum Borrowing Capacity	$ 5,000,000
Line of Credit Facility, Remaining Borrowing Capacity	$ 4,330
Notes Collateralized by Aircraft Security Agreements [Member] \| Note Payable Due September 2017 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Notes Payable, Total	$ 195
Notes Payable to Bank [Member] \| Note 1 Due March 2019 [Member]
Number of Notes	3
Notes Payable, Total	$ 126
Notes Payable to Bank [Member] \| Note 1 Due March 2019 [Member] \| Minimum [Member]
Debt Instrument, Interest Rate, Stated Percentage	3.36%
Notes Payable to Bank [Member] \| Note 1 Due March 2019 [Member] \| Maximum [Member]
Debt Instrument, Interest Rate, Stated Percentage	4.46%
Notes Payable to Bank [Member] \| Debt Instrument Due May 2020 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	4.89%
Notes Payable, Total	$ 1,896,000
Note Collateralized by Real Estate [Member] \| Note Payable Due June 2019 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	6.25%
Notes Payable, Total	$ 250
Note Collateralized by Equipment [Member] \| Note Payable Due April 2022 [Member]
Number of Notes	1
Debt Instrument, Interest Rate, Stated Percentage	4.50%
Notes Payable, Total	$ 71

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

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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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