Note 10 - Debt - Principal Payments Due on Term Loan (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
	$ 148,726	$ 152,100
Loans Payable [Member]
2019	5,600
2020	16,800
2021	21,000
2022	88,200
	$ 131,600

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
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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 in the fourth 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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-SubTopic 10
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-Paragraph 3
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