Note 9 - Long-term Debt and Credit Facility - Long-term Debt (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Long term debt	$ 222,467,000	$ 278,520,000
Less – Current maturities of long-term debt	25,811,000	32,803,000
Less – Unamortized loan costs	2,668,000	2,088,000
Total	193,988,000	243,629,000
Medium-term Notes [Member]
Long term debt	221,717,000	253,750,000
Line of Credit [Member]
Long term debt	0	24,000
Notes Payable, Other Payables [Member]
Long term debt	$ 750,000	$ 770,000

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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