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Note 13 - Commitments and Contingencies (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss	$ 31,534,000	$ 27,992,000
Proceeds from Sale, Loan, Held-for-Sale	411,484,000	708,400,000	$ 1,444,305,000
Other Liabilities	35,737,000	30,999,000
Holdback Reserve For Guaranteed Loans [Member]
Other Liabilities	2,100,000	2,300,000
Federal Home Loan Bank of Des Moines [Member]
Proceeds from Sale, Loan, Held-for-Sale	$ 9,000,000
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation, Percentage	10.00%
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation	$ 39,000
Federal Home Loan Bank of Des Moines [Member] | Financial Asset, 30 to 59 Days Past Due [Member]
Proceeds from Sale, Loan, Held-for-Sale	0	0
Federal Home Loan Bank of Des Moines [Member] | Recourse [Member]
First Loss Account (FLA)	581,000
Credit Enhancement (CE) Obligation	$ 389,000
Credit Enhancement (CE) Obligation, Percentage of Outstanding Loans	4.30%
Unfunded Loan Commitment [Member]
Financing Receivable, Allowance for Credit Loss	$ 1,500,000	2,500,000
Financing Receivable, Allowance for Credit Loss, Recovery	$ 1,000,000	$ 365,000

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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