Note 5 - Securities - Securities in a Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Less than 12 months, fair value	$ 112,186	$ 4,384
Less than 12 months, gross unrealized losses	567	28
12 months or greater, fair value	2,572	51,987
12 months or greater, gross unrealized losses	334	652
Total, fair value	114,758	56,371
Total, gross unrealized losses	901	680
US Government Agencies Debt Securities [Member]
Less than 12 months, fair value	2,595	2,486
Less than 12 months, gross unrealized losses	1	20
12 months or greater, fair value	0	0
12 months or greater, gross unrealized losses	0	0
Total, fair value	2,595	2,486
Total, gross unrealized losses	1	20
Corporate Debt Securities [Member]
Less than 12 months, fair value	12,829	0
Less than 12 months, gross unrealized losses	167	0
12 months or greater, fair value	2,168	6,360
12 months or greater, gross unrealized losses	332	158
Total, fair value	14,997	6,360
Total, gross unrealized losses	499	158
Collateralized Mortgage Backed Securities [Member]
Less than 12 months, fair value	87,915	950
Less than 12 months, gross unrealized losses	375	4
12 months or greater, fair value	24	44,366
12 months or greater, gross unrealized losses	1	493
Total, fair value	87,939	45,316
Total, gross unrealized losses	376	497
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value	8,847	948
Less than 12 months, gross unrealized losses	24	4
12 months or greater, fair value	380	1,261
12 months or greater, gross unrealized losses	1	1
Total, fair value	9,227	2,209
Total, gross unrealized losses	25	5
Other Debt Obligations [Member]
Less than 12 months, fair value	0	0
Less than 12 months, gross unrealized losses	0	0
12 months or greater, fair value	0	0
12 months or greater, gross unrealized losses	0	0
Total, fair value	0	0
Total, gross unrealized losses	$ 0	$ 0