Note 12 - Derivatives and Risk Management Activities - Derivative Instrument Gain (Loss) Recorded in Statement of Income (Details) - Not Designated as Hedging Instrument [Member] - Mortgage Banking Income [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Best Efforts Forward Loan sales Commitments [Member] | Liability Derivatives [Member]
Derivative Gain (Loss), Net	$ 31	$ 158	$ 90	$ 503
Mandatory Forward Loan Sales Commitments [Member] | Liability Derivatives [Member]
Derivative Gain (Loss), Net	1	79	39	767
Interest Rate Lock Commitments [Member] | Liability Derivatives [Member]
Derivative Gain (Loss), Net	(39)	0	(60)	0
Asset Derivatives [Member] | Best Efforts Forward Loan sales Commitments [Member]
Derivative Gain (Loss), Net	68	65	109	65
Asset Derivatives [Member] | Mandatory Forward Loan Sales Commitments [Member]
Derivative Gain (Loss), Net	51	41	89	43
Asset Derivatives [Member] | Interest Rate Lock Commitments [Member]
Derivative Gain (Loss), Net	$ (126)	$ (211)	$ (340)	$ (987)