Note 7 - Loans and the Allowance for Loan Losses - Allowance for Credit Losses and Recorded Investment in Loans Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2023
Beginning Balance, allowance for loan losses	$ 38,178	$ 29,112
Charge-offs	(6,429)	(2,821)
Recoveries	1,044	1,001
Provision (Recovery)	4,961	10,886
Ending Balance, allowance for loan losses	40,414	38,178
Beginning Balance, unfunded loan commitments	605
Provision (Recovery)	(478)
Ending Balance, unfunded loan commitments	3,324	605
Total Allowance for Credit Losses	43,738
Specific allocations	513	2,214	$ 4,210
Collectively Evaluated for Impairment		35,964
Purchased Credit Impaired	40,414	38,178
Ending Balance	4,992,785	4,606,176
Loans balance	4,750	14,707	12,086
Collectively Evaluated for Impairment		4,541,682
Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		49,787
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	2,660
Ending Balance, allowance for loan losses		2,660
Beginning Balance, unfunded loan commitments	3,197
Ending Balance, unfunded loan commitments		3,197
Purchased Credit Impaired		2,660
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	40,838
Ending Balance, allowance for loan losses		40,838
Beginning Balance, unfunded loan commitments	3,802
Ending Balance, unfunded loan commitments		3,802
Purchased Credit Impaired		40,838
Commercial Real Estate Portfolio Segment [Member]
Ending Balance	3,570,120	3,398,858
Commercial Real Estate Portfolio Segment [Member] \| Commercial [Member]
Beginning Balance, allowance for loan losses	14,702	10,515
Charge-offs	(2,049)	(51)
Recoveries	26	50
Provision (Recovery)	174	4,188
Ending Balance, allowance for loan losses	17,676	14,702
Beginning Balance, unfunded loan commitments	220
Provision (Recovery)	(130)
Ending Balance, unfunded loan commitments	206	220
Total Allowance for Credit Losses	17,882
Specific allocations	0	59	1,915
Collectively Evaluated for Impairment		14,643
Purchased Credit Impaired	17,676	14,702
Ending Balance	2,217,928	2,020,406
Loans balance	883	3,053	3,008
Collectively Evaluated for Impairment		1,989,831
Commercial Real Estate Portfolio Segment [Member] \| Commercial [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		27,522
Commercial Real Estate Portfolio Segment [Member] \| Commercial [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	4,823
Ending Balance, allowance for loan losses		4,823
Beginning Balance, unfunded loan commitments	116
Ending Balance, unfunded loan commitments		116
Purchased Credit Impaired		4,823
Commercial Real Estate Portfolio Segment [Member] \| Commercial [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	19,525
Ending Balance, allowance for loan losses		19,525
Beginning Balance, unfunded loan commitments	336
Ending Balance, unfunded loan commitments		336
Purchased Credit Impaired		19,525
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Beginning Balance, allowance for loan losses	5,768	4,498
Charge-offs	(36)	(16)
Recoveries	1	25
Provision (Recovery)	(70)	1,261
Ending Balance, allowance for loan losses	6,596	5,768
Beginning Balance, unfunded loan commitments	137
Provision (Recovery)	(704)
Ending Balance, unfunded loan commitments	1,546	137
Total Allowance for Credit Losses	8,142
Specific allocations		21
Collectively Evaluated for Impairment		5,747
Purchased Credit Impaired	6,596	5,768
Ending Balance	669,798	722,074
Loans balance		992
Collectively Evaluated for Impairment		720,129
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		953
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	933
Ending Balance, allowance for loan losses		933
Beginning Balance, unfunded loan commitments	2,113
Ending Balance, unfunded loan commitments		2,113
Purchased Credit Impaired		933
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	6,701
Ending Balance, allowance for loan losses		6,701
Beginning Balance, unfunded loan commitments	2,250
Ending Balance, unfunded loan commitments		2,250
Purchased Credit Impaired		6,701
Commercial Real Estate Portfolio Segment [Member] \| Residential [Member]
Beginning Balance, allowance for loan losses	5,354	4,565
Charge-offs	(42)	(191)
Recoveries	18	20
Provision (Recovery)	520	960
Ending Balance, allowance for loan losses	5,485	5,354
Beginning Balance, unfunded loan commitments	13
Provision (Recovery)	(26)
Ending Balance, unfunded loan commitments	177	13
Total Allowance for Credit Losses	5,662
Specific allocations		99
Collectively Evaluated for Impairment		5,255
Purchased Credit Impaired	5,485	5,354
Ending Balance	682,394	656,378
Loans balance		4,028
Collectively Evaluated for Impairment		637,195
Commercial Real Estate Portfolio Segment [Member] \| Residential [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		15,155
Commercial Real Estate Portfolio Segment [Member] \| Residential [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	(365)
Ending Balance, allowance for loan losses		(365)
Beginning Balance, unfunded loan commitments	190
Ending Balance, unfunded loan commitments		190
Purchased Credit Impaired		(365)
Commercial Real Estate Portfolio Segment [Member] \| Residential [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	4,989
Ending Balance, allowance for loan losses		4,989
Beginning Balance, unfunded loan commitments	203
Ending Balance, unfunded loan commitments		203
Purchased Credit Impaired		4,989
Commercial Portfolio Segment [Member]
Beginning Balance, allowance for loan losses	11,721	9,016
Charge-offs	(2,813)	(2,139)
Recoveries	672	739
Provision (Recovery)	3,327	4,105
Ending Balance, allowance for loan losses	10,424	11,721
Beginning Balance, unfunded loan commitments	229
Provision (Recovery)	486
Ending Balance, unfunded loan commitments	1,372	229
Total Allowance for Credit Losses	11,796
Specific allocations	0	2,020	1,779
Collectively Evaluated for Impairment		9,701
Purchased Credit Impaired	10,424	11,721
Ending Balance	1,358,838	1,153,873
Loans balance	0	6,442	6,096
Collectively Evaluated for Impairment		1,141,957
Commercial Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		5,474
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	(2,483)
Ending Balance, allowance for loan losses		(2,483)
Beginning Balance, unfunded loan commitments	657
Ending Balance, unfunded loan commitments		657
Purchased Credit Impaired		(2,483)
Commercial Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	9,238
Ending Balance, allowance for loan losses		9,238
Beginning Balance, unfunded loan commitments	886
Ending Balance, unfunded loan commitments		886
Purchased Credit Impaired		9,238
Consumer Portfolio Segment [Member]
Beginning Balance, allowance for loan losses	633	518
Charge-offs	(1,489)	(424)
Recoveries	327	167
Provision (Recovery)	1,010	372
Ending Balance, allowance for loan losses	233	633
Beginning Balance, unfunded loan commitments	6
Provision (Recovery)	(104)
Ending Balance, unfunded loan commitments	23	6
Total Allowance for Credit Losses	256
Specific allocations	0	15	0
Collectively Evaluated for Impairment		618
Purchased Credit Impaired	233	633
Ending Balance	63,827	53,445
Loans balance	0	192	$ 0
Collectively Evaluated for Impairment		52,570
Consumer Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Beginning Balance, allowance for loan losses	0
Ending Balance, allowance for loan losses		0
Purchased Credit Impaired		0
Ending Balance		683
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance, allowance for loan losses	(248)
Ending Balance, allowance for loan losses		(248)
Beginning Balance, unfunded loan commitments	121
Ending Balance, unfunded loan commitments		121
Purchased Credit Impaired		(248)
Consumer Portfolio Segment [Member] \| Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Beginning Balance, allowance for loan losses	385
Ending Balance, allowance for loan losses		385
Beginning Balance, unfunded loan commitments	$ 127
Ending Balance, unfunded loan commitments		127
Purchased Credit Impaired		$ 385

Amount of allowance for credit loss on financing receivable and unfunded loan commitments.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase (decrease) in allowance for credit loss on financing receivable.

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

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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