Note 3 - Accumulated Other Comprehensive Income - Amount Reclassified from Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Gain (loss) on sale of investment securities	$ (1)	$ 0
Provision for income taxes	1,212	1,144
Net income	7,040	7,522
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Gain (loss) on sale of investment securities	(1)	0
Provision for income taxes	0	0
Net income	$ (1)	$ 0