Note 4 - Investment Securities (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 21,102	$ 117,249
Debt Securities, Available-for-Sale, Realized Gain	$ 101	853	1,700
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	195
Pledged Investment Securities	$ 145,700	30,500
Equity Securities, FV-NI, Current	22,158	22,319
Equity Securities, Net Realized Loss From Decrease in Fair Value	$ 291	$ 1,400	$ 1,100
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	159	70
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	22	12
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	6
Collateralized Mortgage Obligations [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	5	3
US Government Corporations and Agencies Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	3	3

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

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- Definition

Pledged investment securities at carrying value.

+ References

No definition available.

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- Definition

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).

+ References

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-Publisher FASB
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- Definition

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.

+ References

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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 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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