Note 10 - Long-term Debt - Long-term Debt (Details) - USD ($)	Jul. 31, 2019	Jul. 31, 2018
Long-term Debt, Gross	$ 20,000,000	$ 20,000,000
Unamortized discount	(400,037)	(465,026)
Long-term debt, net of unamortized discount	19,599,963	19,534,974
Current portion		10,000,000
Long-term debt, net of current portion	$ 19,599,963	$ 9,534,974

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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