Note 4 - Financing Arrangements - Outstanding Borrowings (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Less current portion of long-term debt		$ (250,706)
Long-term debt	1,284,550	898,398
Line of Credit [Member]
Long-term Debt, Total		307,100
Senior Notes [Member]
Long-term Debt, Total	$ 1,284,600	$ 842,000

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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