Note 8 - Goodwill and Intangible Assets (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amortization of Intangible Assets, Total	$ 662,000	$ 610,000	$ 654,000
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	374,000
Finite-Lived Intangible Assets, Amortization Expense, Year Two	318,000
Finite-Lived Intangible Assets, Amortization Expense, Year Three	180,000
Finite-Lived Intangible Assets, Amortization Expense, Year Four	$ 39,000