Note 3 - Investment Securities (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Proceeds from Sale of Debt Securities, Available-for-sale	$ 21,102	$ 117,249	$ 293,849
Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale	424,386	734,485	$ 296,721
Debt Securities, Available-for-sale, Realized Gain	853	1,700
Debt Securities, Available-for-sale, Realized Loss	0	0
Pledged Investment Securities	30,500	22,700
Equity Securities, Net Realized Loss From Decrease in Fair Value	1,400	1,100
Equity Securities, FV-NI, Current	$ 22,319	$ 23,744

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

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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- Definition

Amount of realized loss 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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
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- Definition

Amount of cash inflow from maturity, prepayment and call of 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
-Name Accounting Standards Codification
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-SubTopic 10
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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).

+ References

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-Publisher FASB
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