Note 4 - Fair Value Measurements (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Long-term Debt, Fair Value	$ 116,800	$ 116,800	$ 117,900
Long-term Debt, Total	112,300	112,300	114,200
Goodwill, Impairment Loss		8,891
Goodwill, Ending Balance	10,778	10,778	19,817
North America Reporting Unit [Member]
Goodwill, Impairment Loss	8,900
Goodwill, Impairment Loss, Net of Tax	8,500
Europe Reporting Unit [Member]
Goodwill, Ending Balance	10,800	10,800
Fair Value, Nonrecurring [Member]
Assets, Fair Value Disclosure	0	0	0
Investments Held in Rabbi Trust [Member]
Investments, Fair Value Disclosure, Total	$ 1,200	$ 1,200	$ 1,400