Note 6 - Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 618,931	$ 617,243
Fair Value, Recurring [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	618,931	617,243
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	87,649	87,556
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	531,282	529,687
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	87,649	87,556
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	87,649	87,556
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US Government Corporations and Agencies Securities [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	89,601	85,344
Fair Value, Recurring [Member] \| US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	89,601	85,344
Fair Value, Recurring [Member] \| US Government Corporations and Agencies Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	73,908	75,003
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	73,908	75,003
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	96,060	92,284
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	96,060	92,284
Fair Value, Recurring [Member] \| Collateralized Mortgage Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	271,713	277,056
Fair Value, Recurring [Member] \| Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	271,713	277,056
Fair Value, Recurring [Member] \| Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member] \| Fair Value, Inputs, Level 3 [Member]
Debt Securities, Available-for-Sale, Excluding Accrued Interest	$ 0	$ 0

Note 6 - Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($)
$ in Thousands

Jun. 30, 2026

Dec. 31, 2025

Debt Securities, Available-for-Sale, Excluding Accrued Interest

$ 618,931

$ 617,243

Fair Value, Recurring [Member]

Debt Securities, Available-for-Sale, Excluding Accrued Interest

618,931

617,243

Fair Value, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]

Debt Securities, Available-for-Sale, Excluding Accrued Interest