Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aaa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 326
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-Section 50
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-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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Amount of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
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- Definition

Percentage of increase of market yield on debt securities during a period of time.

+ References

No definition available.

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Note 3 - Investment Securities (Details Textual) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Ending Balance	$ 7	$ 7	$ 7	$ 9
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss, Total	5,254,793	4,951,417
Debt Securities, Held-to-Maturity, Nonaccrual	0
Asset Pledged as Collateral [Member] \| Public Deposits and Short-term Borrowed Funds [Member]
Debt Securities, Available-for-Sale and Held-to-Maturity, after Allowance for Credit Loss, Total	$ 1,023,398	$ 1,021,566
Five-year Treasury Notes [Member]
Debt Securities, Market Yield, Increase	2.83%
Ten-year Treasury Notes [Member]
Debt Securities, Market Yield, Increase	2.32%
Non-treasury Bonds [Member]
Debt Securities, Market Yield, Increase	0.67%