Note 14 - Long-term Debt and Credit Arrangements - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Total debt	$ 414,023	$ 364,352	$ 415,293
Debt issuance costs and other	7,077	6,906	12,793
Long-term Debt, Current Maturities, Total	8,253	8,244	48,397
Long-term Debt, Excluding Current Maturities, Total	405,770	356,108	366,896
Convertible Debt [Member] \| The 2.75% Convertible Notes [Member]
Total debt	196,946	193,696	0
Term Loan [Member] \| The Credit Agreement [Member]
Total debt	135,000	138,750	142,500
Long-term Debt, Current Maturities, Total	7,500	7,500	7,500
Long-term Debt, Excluding Current Maturities, Total	127,500	131,300	135,000
Line of Credit [Member] \| The Credit Agreement [Member] \| Revolving Credit Facility [Member]
Total debt	75,000	25,000	220,000
Senior Notes [Member] \| The 2019 Notes [Member]
Total debt	$ 0	$ 0	$ 40,000

The amount or adjustment of other long-term debt.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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