Note 5 - Loans and Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Beginning balance	$ 32,912	$ 29,337	$ 29,337
Provisions	366	1,500	3,959
Charge-offs	(47)	(42)	(627)
Recoveries	61	0	243
Loans and Leases Receivable, Allowance	33,292	30,795	32,912
Loan losses, Reserves	33,292	30,795	32,912
Individually	20,691	19,911	20,725
Collectively	2,985,793	2,695,294	2,910,625
Total loans, net of deferred loan fees and unaccreted discounts on acquired loans	3,006,484	2,715,205	2,931,350
Specific Reserve [Member]
Loan losses, Reserves	26	524	30
General Reserves [Member]
Loan losses, Reserves	33,266	30,271	32,882
Commercial Real Estate Portfolio Segment [Member]
Beginning balance	28,592	24,677	24,677
Provisions	430	1,257	3,982
Charge-offs	0	0	(67)
Recoveries	0	0	0
Loans and Leases Receivable, Allowance	29,022	25,934	28,592
Loan losses, Reserves	29,022	25,934	28,592
Individually	10,905	11,429	10,340
Collectively	2,618,427	2,302,662	2,545,379
Total loans, net of deferred loan fees and unaccreted discounts on acquired loans	2,629,332	2,314,091	2,555,719
Commercial Real Estate Portfolio Segment [Member] \| Specific Reserve [Member]
Loan losses, Reserves	0	0	0
Commercial Real Estate Portfolio Segment [Member] \| General Reserves [Member]
Loan losses, Reserves	29,022	25,934	28,592
Commercial Portfolio Segment [Member]
Beginning balance	3,793	4,617	4,617
Provisions	(53)	164	(480)
Charge-offs	0	0	(501)
Recoveries	60	0	157
Loans and Leases Receivable, Allowance	3,800	4,781	3,793
Loan losses, Reserves	3,800	4,781	3,793
Individually	9,783	8,482	10,385
Collectively	338,730	388,864	334,460
Total loans, net of deferred loan fees and unaccreted discounts on acquired loans	348,513	397,346	344,845
Commercial Portfolio Segment [Member] \| Specific Reserve [Member]
Loan losses, Reserves	26	524	30
Commercial Portfolio Segment [Member] \| General Reserves [Member]
Loan losses, Reserves	3,774	4,257	3,763
Other Financing Receivables [Member]
Beginning balance	527	43	43
Provisions	(11)	45	457
Charge-offs	(47)	(42)	(59)
Recoveries	1	0	86
Loans and Leases Receivable, Allowance	470	46	527
Loan losses, Reserves	470	46	527
Individually	3	0	0
Collectively	28,636	3,768	30,786
Total loans, net of deferred loan fees and unaccreted discounts on acquired loans	28,639	3,768	30,786
Other Financing Receivables [Member] \| Specific Reserve [Member]
Loan losses, Reserves	0	0	0
Other Financing Receivables [Member] \| General Reserves [Member]
Loan losses, Reserves	470	46	527
Unallocated Financing Receivables [Member]
Beginning balance	0	0	0
Provisions	0	34
Charge-offs	0	0
Recoveries	0	0
Loans and Leases Receivable, Allowance	0	34	0
Loan losses, Reserves	0	34	0
Individually	0	0	0
Collectively	0	0	0
Total loans, net of deferred loan fees and unaccreted discounts on acquired loans	0	0	0
Unallocated Financing Receivables [Member] \| Specific Reserve [Member]
Loan losses, Reserves	0	0	0
Unallocated Financing Receivables [Member] \| General Reserves [Member]
Loan losses, Reserves	$ 0	$ 34	$ 0

Allowance for credit losses reserve change in method of calculating impairment.

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- Definition

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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