Note 13 - Fair Value Measurements and Fair Value of Financial Instruments - Financial Assets and Liabilities Measured on a Non-recurring Basis (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	Dec. 31, 2021
Assets, fair value disclosure		$ 1,624,588		$ 1,624,588		$ 1,540,447
Total Losses		252	$ 1,786	4,069	$ 1,786	4,145	$ 1,172
Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		27,860		27,860		59,158
Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure		424,298		424,298		262,658
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure		1,200,248		1,200,248		1,277,739
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure		42		42		50
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		27,860		27,860		59,158
Impaired Loans [Member]
Total Losses		252	1,786	4,069	1,786	3,877	1,012
Impaired Loans [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		12,085		12,085		54,141
Impaired Loans [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		12,085		12,085		54,141
Impaired Loans [Member] | Commercial Portfolio Segment [Member]
Total Losses		0	1,786	0	1,786	1,786	1,012
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		12,950
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		12,950
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Total Losses		252	0	4,069	0	2,091	0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		7,051		7,051		32,205
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		7,051		7,051		32,205
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member]
Assets, fair value disclosure						8,978
Total Losses						0	0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure						0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure						0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure						8,978
Impaired Loans [Member] | Installment and Other Loans [Member ]
Assets, fair value disclosure						8
Total Losses						0	0
Impaired Loans [Member] | Installment and Other Loans [Member ] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure						0
Impaired Loans [Member] | Installment and Other Loans [Member ] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure						0
Impaired Loans [Member] | Installment and Other Loans [Member ] | Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure						8
Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member]
Total Losses		0	0	0	0
Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		5,034		5,034
Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Real Estate Construction Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		5,034		5,034
Other Real Estate Owned [Member]
Total Losses	[1]	0	0	0	0	0	17
Other Real Estate Owned [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	15,328		15,328		4,328
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	0		0		0
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	0		0		0
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	15,328		15,328		4,328
Investments in Venture Capital [Member]
Total Losses		0	$ 0	0	$ 0	268	$ 143
Investments in Venture Capital [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		447		447		689
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0		0
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		$ 447		$ 447		$ 689

[1] Other real estate owned balance of $14.4 million in the Consolidated Balance Sheets is net of estimated disposal costs.