Note 11 - Borrowed Funds (Details Textual) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Securities Sold under Agreements to Repurchase, Total	$ 0	$ 450,000
Advances from Federal Home Loan Banks, Total	230,000	$ 670,000
Junior Subordinated Notes, Noncurrent	$ 119,100
Junior Subordinated Debt [Member]
Debt Instrument, Interest Rate, Effective Percentage	2.41%	4.09%
Debt Instrument, Term (Year)	30 years
Mature in November 2020 [Member]
Advances from Federal Home Loan Banks, Total	$ 5,000
Mature in May 2021 [Member]
Advances from Federal Home Loan Banks, Total	80,000
Mature in June 2021 [Member]
Advances from Federal Home Loan Banks, Total	50,000
Mature in July 2021 [Member]
Advances from Federal Home Loan Banks, Total	75,000
Mature in May 2023 [Member]
Advances from Federal Home Loan Banks, Total	$ 20,000
Over-night Borrowings [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		1.66%
Non Overnight Borrowings [Member]
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	2.16%	2.26%
Advances from Federal Home Loan Banks, Total	$ 230,000	$ 220,000

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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