Note 8 - Fair Value Disclosures and Reporting and Fair Value Measurements - Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Available-for-sale, net of zero allowance for credit losses	$ 584,897	$ 625,330
Reported Value Measurement [Member]
Cash and cash equivalents	138,307	135,628
Available-for-sale, net of zero allowance for credit losses	584,897	625,330
Securities held-to-maturity, net	277,577	290,811
Loans held for investment, net	2,406,861	2,525,365
Deposits	2,984,741	2,876,436
Repurchase agreements	113,088	130,853
Long-term debt, net	49,551	49,483
Subordinated debentures	36,151	36,017
Reported Value Measurement [Member] \| Other Borrowings [Member]
Other borrowings	52,000	302,700
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	138,307	135,628
Available-for-sale, net of zero allowance for credit losses	584,897	625,330
Securities held-to-maturity, net	247,495	286,461
Loans held for investment, net	2,293,087	2,428,691
Deposits	2,982,414	2,988,239
Repurchase agreements	86,533	107,084
Long-term debt, net	49,131	49,472
Subordinated debentures	35,050	36,276
Estimate of Fair Value Measurement [Member] \| Other Borrowings [Member]
Other borrowings	51,403	302,629
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	138,307	135,628
Available-for-sale, net of zero allowance for credit losses	0	0
Securities held-to-maturity, net	0	0
Loans held for investment, net	0	0
Deposits	1,055,117	995,623
Repurchase agreements	0	0
Long-term debt, net	0	0
Subordinated debentures	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Other Borrowings [Member]
Other borrowings	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Available-for-sale, net of zero allowance for credit losses	583,474	624,017
Securities held-to-maturity, net	247,495	286,461
Loans held for investment, net	0	0
Deposits	1,927,297	1,992,616
Repurchase agreements	86,533	107,084
Long-term debt, net	49,131	49,472
Subordinated debentures	35,050	36,276
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Other Borrowings [Member]
Other borrowings	51,403	302,629
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Available-for-sale, net of zero allowance for credit losses	1,423	1,313
Securities held-to-maturity, net	0	0
Loans held for investment, net	2,293,087	2,428,691
Deposits	0	0
Repurchase agreements	0	0
Long-term debt, net	0	0
Subordinated debentures	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Other Borrowings [Member]
Other borrowings	$ 0	$ 0

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

No definition available.

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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 debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Amount excluding accrued interest, 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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- Definition

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

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- Definition

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 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 fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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