Note 1 - Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Beginning balance, January 1,	$ 3,607	$ 2,072	$ 1,971
Additions due to Acquisitions	0	1,425	0
Additions	929	180	478
Deductions	(62)	(70)	(377)
Ending balance, December 31,	$ 4,474	$ 3,607	$ 2,072