Note 5 - Loans and Allowance for Credit Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Beginning balance	$ 43,092	$ 36,289	$ 41,076	$ 32,912	$ 32,912
Provisions	1,544	1,766	4,297	3,048
Charge-offs	(2,217)	(49)	(2,992)	(151)
Recoveries	11	176	49	238
Ending allowance balance	42,430	38,182	42,430	38,182	41,076
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance			0	2,135	2,135
Ending allowance balance					0
Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance			41,076	35,047	35,047
Ending allowance balance					41,076
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	40,869	32,105	37,935	28,592	28,592
Provisions	963	2,271	4,389	4,172
Charge-offs	(2,150)	0	(2,642)	0	0
Recoveries	0	0	0	0	0
Ending allowance balance	39,682	34,376	39,682	34,376	37,935
Commercial Real Estate Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance			0	1,612	1,612
Ending allowance balance					0
Commercial Real Estate Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance			37,935	30,204	30,204
Ending allowance balance					37,935
Commercial Portfolio Segment [Member]
Beginning balance	1,733	2,646	2,425	3,793	3,793
Provisions	809	(525)	178	(1,128)
Charge-offs	0	(5)	(62)	(5)
Recoveries	1	169	2	229
Ending allowance balance	2,543	2,285	2,543	2,285	2,425
Commercial Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance			0	(604)	(604)
Ending allowance balance					0
Commercial Portfolio Segment [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance			2,425	3,189	3,189
Ending allowance balance					2,425
Other Financing Receivables [Member]
Beginning balance	490	1,538	716	527	527
Provisions	(228)	20	(270)	4
Charge-offs	(67)	(44)	(288)	(146)
Recoveries	10	7	47	9
Ending allowance balance	$ 205	$ 1,521	205	1,521	716
Other Financing Receivables [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning balance			0	1,127	1,127
Ending allowance balance					0
Other Financing Receivables [Member] | Accounting Standards Update 2016-13 [Member] | Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning balance			$ 716	$ 1,654	1,654
Ending allowance balance					$ 716