Note 20 - Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure
Total interest income	$ 49,851	$ 50,890	$ 48,650	$ 48,982	$ 52,977	$ 56,817	$ 54,181	$ 52,101
Total interest expense	6,144	6,309	7,694	11,276	13,058	16,098	16,168	15,193	$ 31,423	$ 60,517	$ 40,484
Net interest income	43,707	44,581	40,956	37,706	39,919	40,719	38,013	36,908	166,950	155,559	142,395
Provision for loan/lease losses	7,080	20,342	19,915	8,367	979	2,012	1,941	2,134	55,704	7,066	12,658
Noninterest income	32,017	37,959	28,626	15,196	29,805	19,906	17,065	11,992	113,798	78,768	41,541
Noninterest expense	46,364	40,838	33,130	31,423	46,294	39,945	36,560	32,435	151,755	155,234	119,143
Income before taxes	22,280	21,360	16,537	13,112	22,451	18,668	16,577	14,331	73,289	72,027	52,135
Federal and state income tax expense	4,009	4,016	2,798	1,884	6,560	3,573	3,073	1,413	12,707	14,619	9,015
Net income	$ 18,271	$ 17,344	$ 13,739	$ 11,228	$ 15,891	$ 15,095	$ 13,504	$ 12,918	$ 60,582	$ 57,408	$ 43,120
Basic (in dollars per share)	$ 1.16	$ 1.10	$ 0.87	$ 0.71	$ 1.01	$ 0.96	$ 0.86	$ 0.82	$ 3.84	$ 3.65	$ 2.92
Diluted (in dollars per share)	$ 1.14	$ 1.09	$ 0.86	$ 0.70	$ 0.99	$ 0.94	$ 0.85	$ 0.81	$ 3.80	$ 3.60	$ 2.86