Note 6 - Investments, Available for Sale ("AFS") (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ 0		$ 0
Debt Securities, Available-for-Sale, Amortized Cost	577,791		584,287
Debt Securities, Available-for-Sale	532,469		$ 537,640
Proceeds from Sale of Debt Securities, Available-for-Sale	0	$ 0
Debt Securities, Available-for-Sale, Gain (Loss)	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	408		416
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss	$ 2,800
Small Business Administration Bonds [Member]
Debt Securities, Available-for-Sale, Amortized Cost	73,124		$ 79,014
Debt Securities, Available-for-Sale	$ 70,800		76,753
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	62
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	$ 371,494		368,081
Debt Securities, Available-for-Sale	$ 341,179		336,170
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	191
Commitments on Mortgage Loans [Member]
Debt Securities, Available-for-Sale, Amortized Cost	$ 87,300
Debt Securities, Available-for-Sale	$ 81,300
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	50
Commitments on Mortgage Loans [Member] \| Moody's, Aa1 Rating [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	31
Tax Exempt Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	13
Taxable Municipal Bonds [Member]
Debt Securities, Available-for-Sale, Amortized Cost	$ 64,649		64,669
Debt Securities, Available-for-Sale	$ 52,752		53,115
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	59
Asset Pledged as Collateral [Member] \| Deposit Accounts, FHLB Advances and Other Borrowings [Member]
Debt Securities, Available-for-Sale, Amortized Cost	$ 521,100		533,700
Debt Securities, Available-for-Sale	$ 479,200		$ 490,500

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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