Note 13 - Assets and Liabilities Measured and Reported at Fair Value - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available-for-sale	$ 1,150,355	$ 1,180,298
Derivative	2,536	3,148
US Treasury Securities and US Government Agencies Debt Securities [Member]
Securities available-for-sale	116,338	122,501
US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale	124,651	135,021
Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale	759,413	846,624
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale	143,835	75,075
Other Debt Obligations [Member]
Securities available-for-sale	6,118	1,077
Fair Value, Recurring [Member]
Securities available-for-sale	1,150,355	1,180,298
Mortgage loans held for sale	9,323
Interest rate swaps	2,536	3,148
Total assets	1,163,010	1,183,446
Interest rate swaps	2,548	3,162
Fair Value, Recurring [Member] \| Rate Lock Loan Commitments [Member]
Derivative	702
Fair Value, Recurring [Member] \| Mandatory Forward Contract [Member]
Derivative	94
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	116,338	122,501
Mortgage loans held for sale	0
Interest rate swaps	0	0
Total assets	116,338	122,501
Interest rate swaps	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Rate Lock Loan Commitments [Member]
Derivative	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 1 [Member] \| Mandatory Forward Contract [Member]
Derivative	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	1,034,017	1,057,797
Mortgage loans held for sale	9,323
Interest rate swaps	2,536	3,148
Total assets	1,046,672	1,060,945
Interest rate swaps	2,548	3,162
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Rate Lock Loan Commitments [Member]
Derivative	702
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 2 [Member] \| Mandatory Forward Contract [Member]
Derivative	94
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	0	0
Mortgage loans held for sale	0
Interest rate swaps	0	0
Total assets	0	0
Interest rate swaps	0	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Rate Lock Loan Commitments [Member]
Derivative	0
Fair Value, Recurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Mandatory Forward Contract [Member]
Derivative	0
Fair Value, Recurring [Member] \| US Treasury and Government [Member]
Securities available-for-sale	116,338
Fair Value, Recurring [Member] \| US Treasury and Government [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	116,338
Fair Value, Recurring [Member] \| US Treasury and Government [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	0
Fair Value, Recurring [Member] \| US Treasury and Government [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	0
Fair Value, Recurring [Member] \| US Treasury Securities and US Government Agencies Debt Securities [Member]
Securities available-for-sale		122,501
Fair Value, Recurring [Member] \| US Treasury Securities and US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale		122,501
Fair Value, Recurring [Member] \| US Treasury Securities and US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale		0
Fair Value, Recurring [Member] \| US Treasury Securities and US Government Agencies Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale		0
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale	124,651	135,021
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	124,651	135,021
Fair Value, Recurring [Member] \| US Government-sponsored Enterprises Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale	759,413	846,624
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	759,413	846,624
Fair Value, Recurring [Member] \| Mortgage-Backed Securities, Issued by US Government Sponsored Enterprises [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale	143,835	75,075
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	143,835	75,075
Fair Value, Recurring [Member] \| US States and Political Subdivisions Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| Other Debt Obligations [Member]
Securities available-for-sale	6,118	1,077
Fair Value, Recurring [Member] \| Other Debt Obligations [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities available-for-sale	0	0
Fair Value, Recurring [Member] \| Other Debt Obligations [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities available-for-sale	6,118	1,077
Fair Value, Recurring [Member] \| Other Debt Obligations [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities available-for-sale	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount 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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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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No definition available.

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Fair value portion of mortgage loans held-for-sale.

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