Note 2 - Acquisitions and Divestitures - Divestitures (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Book value of assets sold		$ (1,685)
Book value of liabilities sold		37
Sales price in excess of net liabilities assumed
Total sales price		(1,648)
Cash sold		35
Non-cash sales price		1,603
Amount due remaining on books
Net cash received in divestitures		$ (10)