Note 2 - Investments, Available for Sale - Schedule of Available for Sale Securities in Unrealized Loss Position (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair value, less than 12 months, AFS	$ 38,646	$ 201,667
Accumulated loss, less than 12 months, AFS	$ 440	$ 15,808
Positions, less than 12 months, AFS	35	205
Fair value, 12 months or more, AFS	$ 441,967	$ 288,502
Accumulated loss, 12 months or more, AFS	$ 47,369	$ 39,232
Positions, 12 months or more, AFS	381	211
Fair value, unrealized loss position, AFS	$ 480,613	$ 490,169
Accumulated loss, total, AFS	47,809	55,040
Collateralized Loan Obligations [Member]
Fair value, less than 12 months, AFS	377	24,768
Accumulated loss, less than 12 months, AFS	$ 1	$ 638
Positions, less than 12 months, AFS	1	16
Fair value, 12 months or more, AFS	$ 43,872	$ 30,684
Accumulated loss, 12 months or more, AFS	$ 727	$ 1,071
Positions, 12 months or more, AFS	34	23
Fair value, unrealized loss position, AFS	$ 44,249	$ 55,452
Accumulated loss, total, AFS	728	1,709
Small Business Administration Bonds [Member]
Fair value, less than 12 months, AFS	2,200	8,404
Accumulated loss, less than 12 months, AFS	$ 5	$ 121
Positions, less than 12 months, AFS	4	18
Fair value, 12 months or more, AFS	$ 39,151	$ 45,969
Accumulated loss, 12 months or more, AFS	$ 2,672	$ 3,126
Positions, 12 months or more, AFS	63	52
Fair value, unrealized loss position, AFS	$ 41,351	$ 54,373
Accumulated loss, total, AFS	2,677	3,247
Tax Exempt Municipal Bonds [Member]
Fair value, less than 12 months, AFS	0	8,051
Accumulated loss, less than 12 months, AFS	$ 0	$ 719
Positions, less than 12 months, AFS	0	9
Fair value, 12 months or more, AFS	$ 12,965	$ 4,929
Accumulated loss, 12 months or more, AFS	$ 908	$ 913
Positions, 12 months or more, AFS	12	4
Fair value, unrealized loss position, AFS	$ 12,965	$ 12,980
Accumulated loss, total, AFS	908	1,632
Taxable Municipal Bonds [Member]
Fair value, less than 12 months, AFS	0	14,428
Accumulated loss, less than 12 months, AFS	$ 0	$ 3,197
Positions, less than 12 months, AFS	0	17
Fair value, 12 months or more, AFS	$ 53,115	$ 36,342
Accumulated loss, 12 months or more, AFS	$ 11,554	$ 11,283
Positions, 12 months or more, AFS	59	43
Fair value, unrealized loss position, AFS	$ 53,115	$ 50,770
Accumulated loss, total, AFS	11,554	14,480
Collateralized Mortgage-Backed Securities [Member]
Fair value, less than 12 months, AFS	36,069	146,016
Accumulated loss, less than 12 months, AFS	$ 434	$ 11,133
Positions, less than 12 months, AFS	30	145
Fair value, 12 months or more, AFS	$ 292,864	$ 170,578
Accumulated loss, 12 months or more, AFS	$ 31,508	$ 22,839
Positions, 12 months or more, AFS	213	89
Fair value, unrealized loss position, AFS	$ 328,933	$ 316,594
Accumulated loss, total, AFS	$ 31,942	$ 33,972