Note 1 - Summary of Significant Accounting Policies - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplemental cash flow information:
Income tax payments	$ 7,227	$ 15,838	$ 12,860
Cash paid for interest	14,827	7,158	4,901
Supplemental non-cash activity:
Transfers from loans to foreclosed assets	$ 2,170		$ 1,916