Note 15 - Accumulated Other Comprehensive Income - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
(Losses) gains recognized									$ 0	$ 0	$ 385
Income before income taxes	$ 15,659	$ 17,462	$ 14,636	$ 12,400	$ 13,592	$ 16,424	$ 17,480	$ 19,032	60,157	66,528	46,112
Income tax benefit	3,076	4,111	3,423	2,885	3,037	3,816	4,077	4,430	13,495	15,360	10,186
Net income	$ 12,583	$ 13,351	$ 11,213	$ 9,515	$ 10,555	$ 12,608	$ 13,403	$ 14,602	46,662	51,168	35,926
Reclassification out of Accumulated Other Comprehensive Income [Member]
(Losses) gains recognized									0	0	(385)
Income tax benefit									0	0	81
Net income									106	308	0
Reclassification out of Accumulated Other Comprehensive Income [Member] | AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent [Member]
Income before income taxes									0	0	(385)
Income tax benefit									(29)	(80)	(82)
Net income									0	0	(304)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Other operating expense									0	124	201
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Other operating expense									135	264	185
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Income before income taxes									135	388	386
Net income									$ 106	$ 308	$ 304