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Note 13 - Restructuring, Impairment and Other Costs (Details Textual) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended
	Mar. 26, 2018	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring, Impairment and Other Costs, Reversal			$ 600		$ 639
Restructuring Charges, Total					(639)
Time-Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number	5,488
Performance-Vested Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Accelerated Vesting, Number	5,488
Employee Severance [Member]
Restructuring Charges, Total
Employee Severance [Member] \| Craig's Separation Agreement [Member]
Deferred Compensation Arrangement with Individual, Term for Base Salary Continuation	1 year
Employee Severance [Member] \| Craig's Separation Agreement [Member] \| Salaries, Wages and Employee Benefits [Member]
Severance Costs					400
Restructuring Charges, Total					$ 700