Note 4 - Loans - Non-accrual Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Non-accrual portfolio loans	$ 40,523	$ 41,815	$ 48,787
Non-accrual loans held-for-sale	0	0	8,000
Total non-accrual loans	40,523	41,815	56,787
Contractual interest due	2,084	3,166	3,302
Nonaccrual Loans [Member]
Contractual interest due	1,775	1,618	3,254
Interest recognized	85	66	86
Net interest foregone	$ 1,690	$ 1,552	$ 3,168