Note 5 - Financial Instruments - Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Equity securities at fair value (Note 2)	$ 8,419		$ 2,896
Securities available for sale (Note 2)	1,028,115		574,787
Deposits – noninterest-bearing	543,165		477,654
Deposits – interest-bearing	1,468,985		1,196,924
Loans to other financial institutions	38,728		35,209
Fair Value, Inputs, Level 1 [Member]
Securities available for sale (Note 2)	0
Fair Value, Inputs, Level 2 [Member]
Securities available for sale (Note 2)	1,009,082
Fair Value, Inputs, Level 3 [Member]
Securities available for sale (Note 2)	19,033
Reported Value Measurement [Member]
Cash and cash equivalents	59,780		79,519
Equity securities at fair value (Note 2)	8,419		2,896
Securities available for sale (Note 2)	1,028,115		574,787
Federal Home Loan Bank and Federal Reserve Bank stock	8,004		8,004
Loans held for sale	7,505		12,921
Loans	980,602		1,062,075
Accrued interest receivable	8,969		6,521
Interest rate lock commitments	438		842
Deposits – noninterest-bearing	543,165		477,654
Deposits – interest-bearing	1,468,985		1,196,924
Subordinated debentures	34,956
Accrued interest payable	202		183
Loans to other financial institutions		$ 35,209
Borrowings			9,327
Subordinated debentures			3,089
Reported Value Measurement [Member] \| Loans to Other Financial Institutions [Member]
Loans	38,728
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	59,780		79,519
Equity securities at fair value (Note 2)	8,419		2,896
Securities available for sale (Note 2)	1,028,115		574,787
Federal Home Loan Bank and Federal Reserve Bank stock	8,004		8,004
Loans held for sale	7,730		13,350
Loans	978,685		1,057,786
Accrued interest receivable	8,969		6,521
Interest rate lock commitments	438		842
Deposits – noninterest-bearing	543,165		477,654
Deposits – interest-bearing	1,469,300		1,197,964
Subordinated debentures	34,415
Accrued interest payable	202		183
Loans to other financial institutions		35,209
Borrowings			9,143
Subordinated debentures			3,089
Estimate of Fair Value Measurement [Member] \| Loans to Other Financial Institutions [Member]
Loans	38,728
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	59,780		79,519
Equity securities at fair value (Note 2)	6,723		1,411
Securities available for sale (Note 2)	0		0
Federal Home Loan Bank and Federal Reserve Bank stock	0		0
Loans held for sale	0		0
Loans	0		0
Accrued interest receivable	0		0
Interest rate lock commitments	0		0
Deposits – noninterest-bearing	0		0
Deposits – interest-bearing	0		0
Subordinated debentures	0
Accrued interest payable	0		0
Loans to other financial institutions		0
Borrowings			0
Subordinated debentures			0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member] \| Loans to Other Financial Institutions [Member]
Loans	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0		0
Equity securities at fair value (Note 2)	0		0
Securities available for sale (Note 2)	1,009,082		563,364
Federal Home Loan Bank and Federal Reserve Bank stock	8,004		8,004
Loans held for sale	7,730		13,350
Loans	0		0
Accrued interest receivable	8,969		6,521
Interest rate lock commitments	438		842
Deposits – noninterest-bearing	543,165		477,654
Deposits – interest-bearing	1,469,300		1,197,964
Subordinated debentures	34,415
Accrued interest payable	202		183
Loans to other financial institutions		35,209
Borrowings			9,143
Subordinated debentures			3,089
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member] \| Loans to Other Financial Institutions [Member]
Loans	38,728
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0		0
Equity securities at fair value (Note 2)	1,696		1,485
Securities available for sale (Note 2)	19,033		11,423
Federal Home Loan Bank and Federal Reserve Bank stock	0		0
Loans held for sale	0		0
Loans	978,685		1,057,786
Accrued interest receivable	0		0
Interest rate lock commitments	0		0
Deposits – noninterest-bearing	0		0
Deposits – interest-bearing	0		0
Subordinated debentures	0
Accrued interest payable	0		0
Loans to other financial institutions		$ 0
Borrowings			0
Subordinated debentures			$ 0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Loans to Other Financial Institutions [Member]
Loans	$ 0

Fair value portion of accrued interest payable.

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Represents the fair value portion of Federal Home Loan Bank Borrowings and Term Loans.

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The amount related to loans to other financial institutions.

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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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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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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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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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The aggregate of all domestic and foreign interest-bearing deposit liabilities.

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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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The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity.

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