Note 17 - Fair Value - Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt securities available for sale	$ 83,358	$ 169,574
FDIC indemnification asset	1,223	2,883	$ 5,108
Interest receivable	9,052	6,677
Derivative liabilities	1,131	510
Reported Value Measurement [Member]
Cash and cash equivalents	456,561	217,009
Debt securities available for sale	83,358	169,574
Equity securities	55	55
Loans held for investment, net of allowance	2,160,450	2,096,035
FDIC indemnification asset	1,223	2,883
Interest receivable	9,052	6,677
Deferred compensation assets	4,181	3,990
Securities sold under agreements to repurchase	964	1,601
Interest payable	582	472
Deferred compensation liabilities	4,181	3,990
Derivative liabilities	1,131	510
Loans held for sale		263
Reported Value Measurement [Member] \| Bank Time Deposits [Member]
Deposits fair value	420,619	515,622
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	456,561	217,009
Debt securities available for sale	83,358	169,574
Equity securities	55	55
Loans held for investment, net of allowance	2,126,221	2,068,257
FDIC indemnification asset	509	1,201
Interest receivable	9,052	6,677
Deferred compensation assets	4,181	3,990
Securities sold under agreements to repurchase	964	1,601
Interest payable	582	472
Deferred compensation liabilities	4,181	3,990
Derivative liabilities	1,131	510
Loans held for sale		263
Estimate of Fair Value Measurement [Member] \| Bank Time Deposits [Member]
Deposits fair value	423,120	512,134
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	456,561	217,009
Debt securities available for sale	0	0
Equity securities	0	0
Loans held for investment, net of allowance	0	0
FDIC indemnification asset	0	0
Interest receivable	0	0
Deferred compensation assets	4,181	3,990
Securities sold under agreements to repurchase	0	0
Interest payable	0	0
Deferred compensation liabilities	4,181	3,990
Derivative liabilities	0	0
Loans held for sale
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Bank Time Deposits [Member]
Deposits fair value	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Debt securities available for sale	83,358	169,574
Equity securities	55	55
Loans held for investment, net of allowance	0	0
FDIC indemnification asset	0	0
Interest receivable	9,052	6,677
Deferred compensation assets	0	0
Securities sold under agreements to repurchase	964	1,601
Interest payable	582	472
Deferred compensation liabilities	0	0
Derivative liabilities	1,131	510
Loans held for sale
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Bank Time Deposits [Member]
Deposits fair value	423,120	512,134
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Debt securities available for sale	0	0
Equity securities	0	0
Loans held for investment, net of allowance	2,126,221	2,068,257
FDIC indemnification asset	509	1,201
Interest receivable	0	0
Deferred compensation assets	0	0
Securities sold under agreements to repurchase	0	0
Interest payable	0	0
Deferred compensation liabilities	0	0
Derivative liabilities	0	0
Loans held for sale		263
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Bank Time Deposits [Member]
Deposits fair value	$ 0	$ 0

Fair value portion of deferred compensation assets.

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Fair value portion of deferred compensation liabilities.

+ References

No definition available.

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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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Amount of equity securities categorized neither as held-to-maturity nor as trading.

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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.

+ References

No definition available.

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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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Carrying amount of receivable assets originating from the indemnification agreement with the Federal Deposit Insurance Corporation (FDIC), in which the FDIC is to partially cover losses.

+ References

No definition available.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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- Definition

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

+ References

No definition available.

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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

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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