Note 11 - Accumulated Other Comprehensive Loss - Summary of Reclassifications from Accumulated Other Comprehensive Loss to Net Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Amortization of defined benefit plan pension items:
Amortization of loss	$ (33)	$ 121
Income tax effect	9	(34)
After tax	(24)	87
Amortization of gain on interest rate swap:
Reclassification to interest expense		(227)
Income tax effect		64
After tax		(163)
Total reclassifications, net of income tax	$ (24)	$ (76)