Note 8 - Long-term Debt - Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
2019	$ 161,955
2020	158,815
2021	103,938
2022	88,155
2023	57,689
Thereafter	30,621
Total	$ 601,173	$ 611,528

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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