Note 12 - Fair Value Measurements - Carrying and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Securities available for sale	$ 643,949	$ 466,091
Reported Value Measurement [Member]
Cash and cash equivalents	518,401	374,370
Securities available for sale	643,949	466,091
Restricted stock	8,046	8,715
Loans held for sale	9,518	15,591
Loans, net of allowance	1,919,702	1,993,653
Bank owned life insurance	28,950	28,482
Accrued interest receivable	5,829	7,193
Deposits	2,862,081	2,611,330
Repurchase agreements	26,595	42,551
Junior subordinated debt		7,500
Accrued interest payable	424	778
Derivative - cash flow hedges	3,265	4,868
Reported Value Measurement [Member] \| Junior Subordinated Debt [Member]
Junior subordinated debt	28,207	28,130
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	518,401	374,370
Securities available for sale	643,949	466,091
Restricted stock	8,046	8,715
Loans held for sale	9,518	15,591
Loans, net of allowance	1,904,320	1,992,326
Bank owned life insurance	28,950	28,482
Accrued interest receivable	5,829	7,193
Deposits	2,864,242	2,615,157
Repurchase agreements	26,595	42,551
Junior subordinated debt		7,522
Accrued interest payable	424	778
Derivative - cash flow hedges	3,265	4,868
Estimate of Fair Value Measurement [Member] \| Junior Subordinated Debt [Member]
Junior subordinated debt	26,037	21,696
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	518,401	374,370
Securities available for sale	0	0
Restricted stock	0	0
Loans held for sale	0	0
Loans, net of allowance	0	0
Bank owned life insurance	0	0
Accrued interest receivable	0	0
Deposits	0	0
Repurchase agreements	0	0
Junior subordinated debt		0
Accrued interest payable	0	0
Derivative - cash flow hedges	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Junior Subordinated Debt [Member]
Junior subordinated debt	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Securities available for sale	643,949	466,091
Restricted stock	8,046	8,715
Loans held for sale	9,518	15,591
Loans, net of allowance	0	0
Bank owned life insurance	28,950	28,482
Accrued interest receivable	5,829	7,193
Deposits	2,864,242	2,615,157
Repurchase agreements	26,595	42,551
Junior subordinated debt		7,522
Accrued interest payable	424	778
Derivative - cash flow hedges	3,265	4,868
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Junior Subordinated Debt [Member]
Junior subordinated debt	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Securities available for sale	0	0
Restricted stock	0	0
Loans held for sale	0	0
Loans, net of allowance	1,904,320	1,992,326
Bank owned life insurance	0	0
Accrued interest receivable	0	0
Deposits	0	0
Repurchase agreements	0	0
Junior subordinated debt		0
Accrued interest payable	0	0
Derivative - cash flow hedges	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Junior Subordinated Debt [Member]
Junior subordinated debt	$ 26,037	$ 21,696

The fair value portion of accrued interest receivable.

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The fair value portion of bank owned life insurance.

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Fair value portion of accrued expenses.

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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).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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- Definition

The aggregate value of all restricted investments.

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Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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