Note 5 - Loans (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Servicing Asset	$ 203,000	$ 181,400
Financing Receivable, Nonaccrual	66,681	68,854
Financing Receivable, Nonaccrual, Average Recorded Investment	71,830	71,371
Financing Receivable, Nonaccrual, Interest Income	$ 321	$ 435	$ 1,074
Percentage Of Charge Off To Contractual Balances For Impaired Loans	15.80%	14.10%
Financing Receivables, Impaired, Troubled Debt Restructuring, Specific Reserve		$ 427	0
Financing Receivable, Modified, Subsequent Default	$ 0	$ 0
Financing Receivable, Troubled Debt Restructuring, Commitment to Lend	$ 0
Minimum [Member]
Period Loan Is In Payment Default (Day)	60 days	60 days
Maximum [Member]
Period Loan Is In Payment Default (Day)	90 days	90 days
Accruing Troubled Debt Restructuring [Member]
Financing Receivable, Troubled Debt Restructuring		$ 15,100
Financing Receivables, Impaired, Troubled Debt Restructuring, Specific Reserve		0
Non-accruing Troubled Debt Restructuring [Member]
Financing Receivable, Troubled Debt Restructuring		6,300
Financing Receivables, Impaired, Troubled Debt Restructuring, Specific Reserve		427
Residential Portfolio Segment [Member]
Servicing Asset	$ 70,700	80,200
Repossessed Assets	242	456
Commercial Real Estate Portfolio Segment [Member]
Servicing Asset	76,100	51,600
Financing Receivable, Nonaccrual, Average Recorded Investment	35,742	14,251
Financing Receivable, Nonaccrual, Interest Income	318	405
Financing Receivables, Impaired, Troubled Debt Restructuring, Specific Reserve		0
Commercial Construction Loans [Member]
Servicing Asset	11,800	2,500
Commercial Portfolio Segment [Member]
Servicing Asset	44,400	47,100
Financing Receivable, Nonaccrual, Average Recorded Investment	18,008	28,109
Financing Receivable, Nonaccrual, Interest Income	3	4
Financing Receivables, Impaired, Troubled Debt Restructuring, Specific Reserve		427	$ 0
Real Estate Loan [Member]
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged	14,150,000	13,070,000
Commercial Loans [Member]
Loans Pledged with Federal Reserve Bank	$ 388	$ 583

Amount of average recorded investments of financing receivable on nonaccrual status. Excludes net investment in lease.

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Reflects the amount of the specific reserve related to a troubled debt restructuring.

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Amount of the collateral pledged in support of loans with Federal Reserve Bank's Discount Window.

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Percentage of charge-off to contractual balances for impaired loans.

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Period Loan Is In Payment Default

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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Amortized cost of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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Amount of interest income on financing receivable on nonaccrual status.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

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Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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