Note 11 - Borrowed Funds (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Advances from Federal Home Loan Banks, Total	$ 75,000	$ 150,000
Junior Subordinated Notes, Noncurrent		$ 119,100
Junior Subordinated Debt [Member]
Junior Subordinated Notes, Noncurrent	$ 119,100
Debt Instrument, Interest Rate, Effective Percentage	2.36%	2.40%
Debt Instrument, Term (Year)	30 years
Mature in May 2021 [Member]
Advances from Federal Home Loan Banks, Total	$ 5,000
Mature in June 2021 [Member]
Advances from Federal Home Loan Banks, Total	50,000
Mature in May 2023 [Member]
Advances from Federal Home Loan Banks, Total	20,000
Over-night Borrowings [Member]
Advances from Federal Home Loan Banks, Total	0	$ 0
Non Overnight Borrowings [Member]
Advances from Federal Home Loan Banks, Total	$ 75,000	$ 150,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	2.26%	2.15%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

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