Note 8 - Loans - Accruing Troubled Debt Restructurings (Details) - Accruing Troubled Debt Restructuring [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Accruing TDRs	$ 27,261	$ 27,864	$ 27,721	$ 31,671	$ 34,364	$ 35,336
Payment Deferral [Member]
Accruing TDRs	6,314		6,222
Contractual Interest Rate Reduction [Member]
Accruing TDRs	5,834		5,910
Rate Reduction and Payment Deferral [Member]
Accruing TDRs	15,113		15,589
Commercial Portfolio Segment [Member]
Accruing TDRs	4,373		3,983
Commercial Portfolio Segment [Member] | Payment Deferral [Member]
Accruing TDRs	4,373		3,983
Commercial Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member]
Accruing TDRs	0		0
Commercial Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Accruing TDRs	0		0
Commercial Real Estate Portfolio Segment [Member]
Accruing TDRs	19,245		19,575
Commercial Real Estate Portfolio Segment [Member] | Payment Deferral [Member]
Accruing TDRs	444		515
Commercial Real Estate Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member]
Accruing TDRs	5,580		5,635
Commercial Real Estate Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Accruing TDRs	13,221		13,425
Residential Portfolio Segment [Member]
Accruing TDRs	3,643		4,163
Residential Portfolio Segment [Member] | Payment Deferral [Member]
Accruing TDRs	1,497		1,724
Residential Portfolio Segment [Member] | Contractual Interest Rate Reduction [Member]
Accruing TDRs	254		275
Residential Portfolio Segment [Member] | Rate Reduction and Payment Deferral [Member]
Accruing TDRs	$ 1,892		$ 2,164