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		12 Months Ended
		Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Assets, fair value disclosure		$ 1,287,058		$ 1,160,854
Total Losses		0	$ 71	1,172	$ 7,836
Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		44,748		28,446
Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure		147,488		22,319
Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure		1,139,546		1,138,512
Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure		24		23
Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		44,748		28,446
Impaired Loans [Member]
Total Losses		0	0	1,012	7,012
Impaired Loans [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		39,532		22,905
Impaired Loans [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		39,532		22,905
Impaired Loans [Member] | Commercial Portfolio Segment [Member]
Total Losses		0	0	1,012	7,012
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		19,688		4,327
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		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
Impaired Loans [Member] | Commercial Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		19,688		4,327
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member]
Total Losses		0	0	0	0
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		13,665		13,335
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
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
Impaired Loans [Member] | Commercial Real Estate Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		13,665		13,335
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member]
Assets, fair value disclosure		6,179		5,243
Total Losses		0	0	0	0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 1 [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 2 [Member]
Assets, fair value disclosure		0		0
Impaired Loans [Member] | Residential Mortgage and Equity Lines Portfolio Segment [Member] | Fair Value, Inputs, Level 3 [Member]
Assets, fair value disclosure		6,179		5,243
Other Real Estate Owned [Member]
Total Losses	[1]	0	0	17	717
Other Real Estate Owned [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	4,269		4,589
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	0		0
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	0		0
Other Real Estate Owned [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure	[1]	4,269		4,589
Investments in Venture Capital [Member]
Total Losses		0	$ 71	143	$ 107
Investments in Venture Capital [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		947		952
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		0		0
Investments in Venture Capital [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Nonrecurring [Member]
Assets, fair value disclosure		$ 947		$ 952

[1] Other real estate owned balance of $4.1 million in the Consolidated Balance Sheets is net of estimated disposal costs.