Note 12 - Long-term Debt - Long-term Debt and Convertible Debentures (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Revolving credit facility	$ 262,498	$ 260,947
Capital leases maturing at various dates through 2019	1,868	1,870
Other long-term debt maturing at various dates up to 2020	1,549	3,912
	262,498	260,947
Less: current portion	1,961	3,200
Long-term debt - non-current	260,537	257,747
Revolving Credit Facility [Member]
Revolving credit facility	$ 259,081	$ 255,165

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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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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