Accrued interest rate on deferred bonus.

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Represents the amount of deferred bonus accrued in other liabilities.

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No definition available.

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Represents the threshold for deferred bonus.

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Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

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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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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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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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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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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of interest expense classified as other.

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No definition available.

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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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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Note 10 - Borrowed Funds (Details Textual) - USD ($) $ in Thousands					12 Months Ended
	Mar. 28, 2019	Nov. 23, 2014	Mar. 13, 2014	Nov. 23, 2004	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Securities Sold under Agreements to Repurchase					$ 0	$ 0	$ 0
Advance from Federal Home Loan Bank					540,000	485,000
Federal Home Loan Bank, Advances, General Debt Obligations, Amount of Available, Unused Funds					6,600,000
Debt Securities, Available-for-Sale					1,604,570	1,473,348
Threshold for Deferred Bonus				$ 225
Amount of Deferred Bonus Accrued in Other Liabilities			$ 300	$ 610
Accrued Interest on Deferred Bonus	5.72%	5.06%	5.02%	7.00%
Accrued Bonuses					2,400	2,300
Interest Expense, Other					122	$ 116	110
Junior Subordinated Notes, Noncurrent					$ 119,100
Junior Subordinated Debt [Member]
Debt Instrument, Term (Year)					30 years
Debt Instrument, Interest Rate, Effective Percentage					7.54%	4.01%
Interest Expense, Debt					$ 6,500	$ 5,500	$ 5,800
Federal Home Loan Bank Securities [Member] \| Asset Not Pledged as Collateral [Member]
Debt Securities, Available-for-Sale					1,470,000
Mature in January 2024 [Member]
Advance from Federal Home Loan Bank					525,000
Mature in September 2024 [Member]
Advance from Federal Home Loan Bank					15,000
Ten-year Treasury Note [Member]
Debt Instrument, Basis Spread on Variable Rate		2.75%
Debt Instrument, Term (Year)		10 years
Five-year Treasury Note [Member]
Debt Instrument, Basis Spread on Variable Rate	3.50%
Debt Instrument, Term (Year)	5 years
Over-night Borrowings [Member]
Advance from Federal Home Loan Bank					0	$ 150,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate						4.65%
Non Overnight Borrowings [Member]
Advance from Federal Home Loan Bank					$ 540,000	$ 335,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate					5.64%	4.54%