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Note 11 - Borrowing Arrangements (Details Textual) - USD ($) $ in Thousands		12 Months Ended
	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, before Allowance for Credit Loss		$ 3,053,230	$ 3,031,861
Advances from Federal Home Loan Banks, Total		200,000	150,000
Other Financial Institutions [Member]
Line of Credit Facility, Maximum Borrowing Capacity		97,000
Federal Home Loan Bank Overnight Advances [Member]
Long-Term Federal Home Loan Bank Advances		0
Advances from Federal Home Loan Banks, Total		0
Federal Home Loan Bank Secured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		1,100
Federal Home Loan Bank Secured Line of Credit [Member] \| Asset Pledged as Collateral [Member]
Financing Receivable, before Allowance for Credit Loss		1,400
Federal Home Loan Bank of San Francisco [Member]
Long-Term Federal Home Loan Bank Advances		200,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		2,200	$ 2,900	$ 2,900
Federal Home Loan Bank of San Francisco [Member] \| Putable Advances [Member]
Long-Term Federal Home Loan Bank Advances	$ 50,000
Debt Instrument, Term (Year)	4 years
Federal Home Loan Bank, Advance, Branch of FHLBank, Interest Rate	3.42%
Federal Home Loan Bank of San Francisco [Member] \| Debt Instrument, Maturing 2025 [Member]
Long-Term Federal Home Loan Bank Advances		$ 150,000
Debt Instrument, Term (Year)		5 years
Federal Home Loan Bank, Advances, Activity for Year, Average Interest Rate at Period End			1.18%
Federal Home Loan Bank of San Francisco Secured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity		$ 47,200
Federal Home Loan Bank of San Francisco Secured Line of Credit [Member] \| Asset Pledged as Collateral [Member]
Financing Receivable, before Allowance for Credit Loss		$ 62,500