Note 8 - Income Taxes (Details Textual) - USD ($)		3 Months Ended		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2017
Income Tax Expense (Benefit), Total		$ (8,317,000)	$ (16,850,000)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest, Total		$ 29,850,000	$ 2,111,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	24.28%		35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability		$ (16,000,000)
Income Tax Expense (Benefit), Continuing Operations, Revaluation Differences in Deferred Taxes		$ (20,000,000)
Effective Income Tax Rate Reconciliation, Percent, Total		28.00%	798.00%
Domestic Tax Authority [Member] | Earliest Tax Year [Member]
Open Tax Year		2015
State and Local Jurisdiction [Member] | Earliest Tax Year [Member]
Open Tax Year		2013