Note 2 - Investment Securities - Investment Securities Available for Sale (Details) $ in Thousands	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of investment positions - less than twelve months, available for sale	331	122
Fair value - less than twelve months, available for sale	$ 323,581	$ 247,386
Gross unrealized losses - less than twelve months, available for sale	$ 19,173	$ 3,341
Number of investment positions - more than twelve months , available for sale	30	9
Fair value - more than twelve months, available for sale	$ 53,380	$ 17,990
Gross unrealized losses - more than twelve months, available for sale	$ 4,488	$ 456
Number of investment positions, available for sale	361	131
Fair value, available for sale	$ 376,961	$ 265,376
Gross unrealized losses, available for sale	$ 23,661	$ 3,797
Number of investment positions - less than twelve months, held to maturity	4
Fair value - less than twelve months, held to maturity	$ 6,633
Gross unrealized losses - less than twelve months, held to maturity	$ 367
Number of investment positions, held to maturity	4
Fair value, held to maturity	$ 6,633
Gross unrealized losses, held to maturity	$ 367
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Number of investment positions - less than twelve months, available for sale	93	23
Fair value - less than twelve months, available for sale	$ 93,083	$ 67,512
Gross unrealized losses - less than twelve months, available for sale	$ 4,596	$ 607
Number of investment positions - more than twelve months , available for sale	4	1
Fair value - more than twelve months, available for sale	$ 5,607	$ 1,357
Gross unrealized losses - more than twelve months, available for sale	$ 442	$ 28
US Government Agencies Debt Securities [Member]
Number of investment positions - less than twelve months, available for sale	35	39
Fair value - less than twelve months, available for sale	$ 79,439	$ 98,042
Gross unrealized losses - less than twelve months, available for sale	$ 4,416	$ 1,710
Number of investment positions - more than twelve months , available for sale	15	4
Fair value - more than twelve months, available for sale	$ 41,339	$ 13,676
Gross unrealized losses - more than twelve months, available for sale	$ 3,010	$ 324
Agency Collateralized Mortgage Obligations [Member]
Number of investment positions - less than twelve months, available for sale	20
Fair value - less than twelve months, available for sale	$ 4,553
Gross unrealized losses - less than twelve months, available for sale	$ 64
US Treasury and Government [Member]
Number of investment positions - less than twelve months, available for sale	14	11
Fair value - less than twelve months, available for sale	$ 48,766	$ 49,190
Gross unrealized losses - less than twelve months, available for sale	$ 2,001	$ 545
US States and Political Subdivisions Debt Securities [Member]
Number of investment positions - less than twelve months, available for sale	169	49
Fair value - less than twelve months, available for sale	$ 97,740	$ 32,642
Gross unrealized losses - less than twelve months, available for sale	$ 8,096	$ 479
Municipal Notes [Member]
Number of investment positions - more than twelve months , available for sale	11	4
Fair value - more than twelve months, available for sale	$ 6,434	$ 2,957
Gross unrealized losses - more than twelve months, available for sale	$ 1,036	$ 104
Corporate Note Securities [Member]
Number of investment positions - less than twelve months, held to maturity	4
Fair value - less than twelve months, held to maturity	$ 6,633
Gross unrealized losses - less than twelve months, held to maturity	$ 367