Note 3 - Accumulated Other Comprehensive Income - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Balance	$ 407,774	$ 386,730	$ 386,803	$ 383,598	$ 373,403	$ 357,989	$ 386,803	$ 357,989
Other comprehensive income, net of tax	(1,360)	882	391	1,031	930	896	(87)	2,857
Balance	400,299	407,774	386,730	361,023	383,598	373,403	400,299	361,023
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Balance			822			(545)	822	(545)
Other comprehensive income (loss) before reclassification							825	1,419
Reclassification of (gains) losses from other comprehensive income							8	25
Other comprehensive income, net of tax							833	1,444
Balance	1,655			899			1,655	899
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Balance			340			(41)	340	(41)
Other comprehensive income (loss) before reclassification							(510)	1,423
Reclassification of (gains) losses from other comprehensive income							(410)	(10)
Other comprehensive income, net of tax							(920)	1,413
Balance	(580)			1,372			(580)	1,372
AOCI Attributable to Parent [Member]
Balance	2,435	1,553	1,162	1,240	310	(586)	1,162	(586)
Other comprehensive income (loss) before reclassification							315	2,842
Reclassification of (gains) losses from other comprehensive income							(402)	15
Other comprehensive income, net of tax	(1,360)	882	391	1,031	930	896	(87)	2,857
Balance	$ 1,075	$ 2,435	$ 1,553	$ 2,271	$ 1,240	$ 310	$ 1,075	$ 2,271