Note 4 - Investment Securities (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 0	$ 21,102
Debt Securities, Available-for-Sale, Realized Gain	0		853
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-Sale, Transfer in, Allowance for Credit Loss, Expense	$ 0	0	0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	192
Pledged Investment Securities	$ 134,200	145,700
Equity Securities, FV-NI, Current	40,406	22,158
Equity Securities, Net Realized Loss From Decrease in Fair Value	18,200	291	1,400
Proceeds from Sale, Debt Security, Trading, and Equity Security, FV-NI, Held-for-Investment	$ 0	553	$ 0
Equity Securities, FV-NI, Realized Gain (Loss)		$ (101)
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	154	159
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	24	22
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	1	6
Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	5	5
US Government Corporations and Agencies Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	8	3

The net realized loss from decrease in fair value of equity securities.

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Pledged investment securities at carrying value.

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No definition available.

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Amount of allowance for credit loss on 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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Amount of realized gain on 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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) transferred into available-for-sale out of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of cash inflow from sale 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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The cash inflow associated with the sale of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

+ References

No definition available.

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