Note 13 - Fair Value Measurements - Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Available-for-sale securities	$ 344,040	$ 420,862
Fair Value, Recurring [Member]
Available-for-sale securities	344,040	420,862
Total assets	344,211	421,075
Total liabilities	2,332	213
Fair Value, Recurring [Member] | Interest Rate Swap [Member]
Interest rate swaps	171	213
Interest rate swaps	2,332	213
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities	0	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member]
Interest rate swaps	0	0
Interest rate swaps	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities	344,040	420,862
Total assets	344,211	421,075
Total liabilities	2,332	213
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member]
Interest rate swaps	171	213
Interest rate swaps	2,332	213
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities	0	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member]
Interest rate swaps	0	0
Interest rate swaps	0	0
US Government Agencies Debt Securities [Member]
Available-for-sale securities	27,545	31,533
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member]
Available-for-sale securities	27,545	31,533
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities	0	0
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities	27,545	31,533
US Government Agencies Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities	0	0
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities	122,797	171,894
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member]
Available-for-sale securities	122,797	171,894
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities	0	0
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities	122,797	171,894
US States and Political Subdivisions Debt Securities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities	193,698	217,435
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member]
Available-for-sale securities	193,698	217,435
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities	0	0
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities	193,698	217,435
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities	$ 0	$ 0