Note 6 - Long-term Debt and Capital Leases - Long-term Debt and Capital Lease Obligations (Details) - USD ($) $ in Thousands	Jun. 06, 2017	May 31, 2016	May 14, 2012
Unamortized (discount) premium - mortgage loan obligations	$ (1)	$ 75
Unamortized debt issuance costs	(27)	(74)
Mortgage loan obligations	4,650	15,745
Capital lease obligations	218	211
Total long-term debt and capital leases	213,709	223,737
Less current maturities	368	9,934
Long-term debt and capital leases, less current maturities	213,341	213,803
Senior Notes [Member]
Senior unsecured notes	212,546	212,546
Unamortized discount	(1,366)	(1,771)	$ (3,700)
Unamortized debt issuance costs	(2,311)	(2,995)
Senior unsecured notes less unamortized discount and debt issuance costs	$ 208,869	$ 207,780

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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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 accumulated amortization, of debt premium.

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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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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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