Note 14 - Postemployment Benefit Plans - Amounts Recognized in Balance Sheet (Details) - Defined Benefit Supplemental Executive Retirement Plan [Member] - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Accounts payable and accrued liabilities	$ 282	$ 323
Other noncurrent liabilities	4,358	4,864
Total liabilities	$ 4,640	$ 5,187

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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