Note 8 - Long-term Debt - Debt Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
2020	$ 189,265
2021	127,557
2022	115,337
2023	96,053
2024	66,424
Thereafter	33,042
Total	$ 627,678	$ 601,173

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
-Name Accounting Standards Codification
-Topic 470
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-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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