Note 2 - Investment Securities - Investment Securities Continuous Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Number of investment positions - less than twelve months, available for sale	367	122
Fair value - less than twelve months, available for sale	$ 233,540	$ 247,386
Gross unrealized losses - less than twelve months, available for sale	$ 24,404	$ 3,341
Number of investment positions - more than twelve months , available for sale	113	9
Fair value - more than twelve months, available for sale	$ 213,084	$ 17,990
Gross unrealized losses - more than twelve months, available for sale	$ 28,279	$ 456
Number of investment positions, available for sale	480	131
Fair value, available for sale	$ 446,624	$ 265,376
Gross unrealized losses, available for sale	$ 52,683	$ 3,797
Number of investment positions - less than twelve months, held to maturity	4
Fair value - less than twelve months, held to maturity	$ 5,618
Gross unrealized losses - less than twelve months, held to maturity	$ 1,382
Number of investment positions, held to maturity	4
Fair value, held to maturity	$ 5,618
Gross unrealized losses, held to maturity	$ 1,382
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Number of investment positions - less than twelve months, available for sale	78	23
Fair value - less than twelve months, available for sale	$ 40,860	$ 67,512
Gross unrealized losses - less than twelve months, available for sale	$ 4,440	$ 607
Number of investment positions - more than twelve months , available for sale	20	1
Fair value - more than twelve months, available for sale	$ 45,849	$ 1,357
Gross unrealized losses - more than twelve months, available for sale	$ 7,742	$ 28
US Government Agencies Debt Securities [Member]
Number of investment positions - less than twelve months, available for sale	20	39
Fair value - less than twelve months, available for sale	$ 39,992	$ 98,042
Gross unrealized losses - less than twelve months, available for sale	$ 1,724	$ 1,710
Number of investment positions - more than twelve months , available for sale	39	4
Fair value - more than twelve months, available for sale	$ 97,356	$ 13,676
Gross unrealized losses - more than twelve months, available for sale	$ 11,645	$ 324
Agency Collateralized Mortgage Obligations [Member]
Number of investment positions - less than twelve months, available for sale	26
Fair value - less than twelve months, available for sale	$ 7,232
Gross unrealized losses - less than twelve months, available for sale	$ 370
US Treasury and Government [Member]
Number of investment positions - less than twelve months, available for sale	20	11
Fair value - less than twelve months, available for sale	$ 33,041	$ 49,190
Gross unrealized losses - less than twelve months, available for sale	$ 976	$ 545
Number of investment positions - more than twelve months , available for sale	11
Fair value - more than twelve months, available for sale	$ 46,379
Gross unrealized losses - more than twelve months, available for sale	$ 3,131
US States and Political Subdivisions Debt Securities [Member]
Number of investment positions - less than twelve months, available for sale	223	49
Fair value - less than twelve months, available for sale	$ 112,415	$ 32,642
Gross unrealized losses - less than twelve months, available for sale	$ 16,894	$ 479
Municipal Notes [Member]
Number of investment positions - more than twelve months , available for sale	43	4
Fair value - more than twelve months, available for sale	$ 23,500	$ 2,957
Gross unrealized losses - more than twelve months, available for sale	$ 5,761	$ 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	$ 5,618
Gross unrealized losses - less than twelve months, held to maturity	$ 1,382