Note 6 - Allowance for Credit Losses and Credit Quality Information - Credit Quality Indicators (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Year one	$ 173,139
Year two	271,054
Year three	180,364
Year four	125,999
Year five	28,889
Prior	32,502
Revolving	46,161
Total	858,108	$ 787,887
Current period gross write offs, total	384	115
Classified [Member]
Total		37,927
Unclassified [Member]
Total		749,960
Special Mention [Member] | Classified [Member]
Total		22,684
Substandard [Member] | Classified [Member]
Total		15,090
Doubtful [Member] | Classified [Member]
Total		67
Unlikely to be Collected Financing Receivable [Member] | Classified [Member]
Total		86
Residential Portfolio Segment [Member]
Year one	81,134
Year two	60,531
Year three	62,690
Year four	33,716
Year five	11,121
Prior	15,111
Revolving	0
Total	264,303	205,890
Current period gross write offs, total	(0)	(0)
Residential Portfolio Segment [Member] | Classified [Member]
Total		2,996
Residential Portfolio Segment [Member] | Unclassified [Member]
Total		202,894
Residential Portfolio Segment [Member] | Unclassified [Member]
Year one	81,070
Year two	59,474
Year three	62,690
Year four	33,637
Year five	10,915
Prior	14,635
Revolving	0
Total	262,421
Residential Portfolio Segment [Member] | Special Mention [Member]
Year one	0
Year two	511
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	511
Residential Portfolio Segment [Member] | Special Mention [Member] | Classified [Member]
Total		882
Residential Portfolio Segment [Member] | Substandard [Member]
Year one	64
Year two	546
Year three	0
Year four	79
Year five	182
Prior	462
Revolving	0
Total	1,333
Residential Portfolio Segment [Member] | Substandard [Member] | Classified [Member]
Total		2,067
Residential Portfolio Segment [Member] | Doubtful [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	24
Prior	14
Revolving	0
Total	38
Residential Portfolio Segment [Member] | Doubtful [Member] | Classified [Member]
Total		47
Residential Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Classified [Member]
Total		0
Residential Portfolio Segment [Member] | Loss [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	0
Commercial Real Estate Portfolio Segment [Member]
Year one	67,939
Year two	195,464
Year three	112,209
Year four	86,992
Year five	15,168
Prior	12,181
Revolving	0
Total	489,953	471,345
Current period gross write offs, total	(0)	91
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member]
Total	271,531	249,783
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Total	218,422	221,562
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Real Estate Loan [Member]
Total		11,770
Commercial Real Estate Portfolio Segment [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Total		19,865
Commercial Real Estate Portfolio Segment [Member] | Unclassified [Member] | Real Estate Loan [Member]
Total		238,013
Commercial Real Estate Portfolio Segment [Member] | Unclassified [Member] | Commercial Real Estate Other [Member]
Total		201,697
Commercial Real Estate Portfolio Segment [Member] | Unclassified [Member]
Year one	64,688
Year two	187,320
Year three	109,729
Year four	75,754
Year five	14,531
Prior	9,603
Revolving	0
Total	461,625
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member]
Year one	1,026
Year two	7,756
Year three	2,188
Year four	371
Year five	0
Prior	1,016
Revolving	0
Total	12,357
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Classified [Member] | Real Estate Loan [Member]
Total		9,529
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Total		11,273
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Year one	2,225
Year two	388
Year three	292
Year four	10,867
Year five	637
Prior	1,562
Revolving	0
Total	15,971
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Classified [Member] | Real Estate Loan [Member]
Total		2,241
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Total		8,592
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	0
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Classified [Member] | Real Estate Loan [Member]
Total		0
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Total		0
Commercial Real Estate Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Classified [Member] | Real Estate Loan [Member]
Total		0
Commercial Real Estate Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Classified [Member] | Commercial Real Estate Other [Member]
Total		0
Commercial Real Estate Portfolio Segment [Member] | Loss [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	0
Consumer Portfolio Segment [Member]
Year one	9,959
Year two	7,609
Year three	1,774
Year four	1,870
Year five	2,372
Prior	4,891
Revolving	14,259
Total	42,734	44,817
Current period gross write offs, year one	0
Current period gross write offs, year two	1
Current period gross write offs, year three	0
Current period gross write offs, year four	0
Current period gross write offs, year five	0
Current period gross write offs, prior	49
Current period gross write offs, revolving	0
Current period gross write offs, total	50	24
Consumer Portfolio Segment [Member] | Classified [Member]
Total		493
Consumer Portfolio Segment [Member] | Unclassified [Member]
Total		44,324
Consumer Portfolio Segment [Member] | Unclassified [Member]
Year one	9,913
Year two	7,583
Year three	1,606
Year four	1,870
Year five	2,369
Prior	4,778
Revolving	14,170
Total	42,289
Consumer Portfolio Segment [Member] | Special Mention [Member]
Year one	20
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	20
Consumer Portfolio Segment [Member] | Special Mention [Member] | Classified [Member]
Total		0
Consumer Portfolio Segment [Member] | Substandard [Member]
Year one	8
Year two	26
Year three	52
Year four	0
Year five	3
Prior	113
Revolving	30
Total	232
Consumer Portfolio Segment [Member] | Substandard [Member] | Classified [Member]
Total		387
Consumer Portfolio Segment [Member] | Doubtful [Member]
Year one	15
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	19
Total	34
Consumer Portfolio Segment [Member] | Doubtful [Member] | Classified [Member]
Total		20
Consumer Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Classified [Member]
Total		86
Consumer Portfolio Segment [Member] | Loss [Member]
Year one	3
Year two	0
Year three	116
Year four	0
Year five	0
Prior	0
Revolving	40
Total	159
Commercial Portfolio Segment [Member]
Year one	14,107
Year two	7,450
Year three	3,691
Year four	3,421
Year five	228
Prior	319
Revolving	31,902
Total	61,118	65,835
Current period gross write offs, year one	174
Current period gross write offs, year two	0
Current period gross write offs, year three	0
Current period gross write offs, year four	0
Current period gross write offs, year five	0
Current period gross write offs, prior	0
Current period gross write offs, revolving	160
Current period gross write offs, total	334	(0)
Commercial Portfolio Segment [Member] | Classified [Member]
Total		2,803
Commercial Portfolio Segment [Member] | Unclassified [Member]
Total		63,032
Commercial Portfolio Segment [Member] | Unclassified [Member]
Year one	12,404
Year two	6,967
Year three	3,539
Year four	3,317
Year five	217
Prior	288
Revolving	30,160
Total	56,892
Commercial Portfolio Segment [Member] | Special Mention [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	0
Commercial Portfolio Segment [Member] | Special Mention [Member] | Classified [Member]
Total		1,000
Commercial Portfolio Segment [Member] | Substandard [Member]
Year one	1,703
Year two	483
Year three	152
Year four	104
Year five	11
Prior	31
Revolving	1,742
Total	4,226
Commercial Portfolio Segment [Member] | Substandard [Member] | Classified [Member]
Total		1,803
Commercial Portfolio Segment [Member] | Doubtful [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	0
Commercial Portfolio Segment [Member] | Doubtful [Member] | Classified [Member]
Total		0
Commercial Portfolio Segment [Member] | Unlikely to be Collected Financing Receivable [Member] | Classified [Member]
Total		$ 0
Commercial Portfolio Segment [Member] | Loss [Member]
Year one	0
Year two	0
Year three	0
Year four	0
Year five	0
Prior	0
Revolving	0
Total	$ 0