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Note 8 - Commitments and Contingencies (Details Textual) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	$ 3,985,000	$ 1,597,000	$ 6,886,000	$ 4,315,000
Proceeds from Sale, Loan, Held-for-Sale			379,654,000	430,421,000
Other Liabilities	35,880,000		35,880,000		$ 31,036,000
Holdback Reserve For Guaranteed Loans [Member]
Other Liabilities	$ 1,800,000		1,800,000		2,000,000
Federal Home Loan Bank of Des Moines [Member]
Proceeds from Sale, Loan, Held-for-Sale			$ 8,400,000
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation, Percentage	10.00%		10.00%
Escrow Holdback Relative to Outstanding Credit Enhancement (CE) Obligation	$ 39,000		$ 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		581,000
Credit Enhancement (CE) Obligation	$ 389,000		$ 389,000
Credit Enhancement (CE) Obligation, Percentage of Outstanding Loans	4.60%		4.60%
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	$ 2,300,000	(0)	$ 2,300,000	(0)
Unfunded Loan Commitment [Member]
Financing Receivable, Allowance for Credit Loss	2,100,000		2,100,000		$ 1,400,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Writeoff (Recovery)	$ 457,000	$ 78,000	675,000	$ 24,000
Commercial and Speculative Construction and Development [Member] | Commercial Real Estate Portfolio Segment [Member] | Commitments to Extend Credit [Member]
Financing Receivable, Excluding Accrued Interest, Increase/Decrease in Provisions			$ 85,700,000

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- Definition

Represents the amount established as A Percentage of Outstanding Credit Enhancement (CE) Obligation

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