Note 2 - Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Apr. 30, 2018	Apr. 30, 2017
Promissory notes	$ 2,387	$ 2,604
Long-Term Debt
Notes payable	3,347	5,644
Less: Current maturities	1,612	2,297
	1,735	3,347
Note Payable Paid off in 2017 [Member]
Long-Term Debt
Notes payable		46
Debt Instrument Due December 2017 and March 2018 [Member]
Long-Term Debt
Notes payable		685
Note Collateralized by Real Estate [Member]
Promissory notes	2,387	2,604
Note Collateralized by Real Estate [Member] \| Note Payable Due August 2019 [Member]
Long-Term Debt
Notes payable	62	128
Note Collateralized by Real Estate [Member] \| Note 1 Due March 2019 [Member]
Long-Term Debt
Notes payable	65	132
Note Collateralized by Real Estate [Member] \| Note 2 Due March 2019 [Member]
Long-Term Debt
Notes payable	147	307
Note Collateralized by Real Estate [Member] \| Note Payable Due June 2016 [Member]
Long-Term Debt
Notes payable	259	276
Notes Collateralized by Aircraft Security Agreements [Member] \| Note Payable Due September 2017 [Member]
Long-Term Debt
Notes payable	270	412
Note Collateralized by BNSC's Assets and Compensation due under State Management Contract [Member] \| Debt Instrument Due May 2020 [Member]
Long-Term Debt
Notes payable	2,464	3,560
Note Collateralized by Equipment [Member] \| Note Payable Due April 2020 [Member]
Long-Term Debt
Notes payable	$ 80	$ 98

The carrying value as of the balance sheet date of the current portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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