Note 14 - Long-term Debt and Credit Arrangements - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Total debt	$ 403,104	$ 382,405	$ 433,722
Other	12,479	(845)	(1,062)
Long-term Debt, Current Maturities, Total	8,263	47,286	116,796
Long-term Debt, Excluding Current Maturities, Total	394,841	335,119	316,926
Senior Notes [Member] \| The 2019 Notes [Member]
Total debt	0	40,000	80,000
Long-term Debt, Current Maturities, Total		40,000	40,000
Term Loan [Member] \| The Credit Agreement [Member]
Total debt	140,625	146,250	148,125
Long-term Debt, Current Maturities, Total	7,500
Long-term Debt, Excluding Current Maturities, Total	133,100	138,800	140,600
Line of Credit [Member] \| The Credit Agreement [Member] \| Revolving Credit Facility [Member]
Total debt	250,000	197,000	137,000
Convertible Debt [Member]
Total debt	$ 0	$ 0	$ 69,659

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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