Note 11 - Borrowing Arrangements (Details Textual) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Long-Term Federal Home Loan Bank Advances	$ 160,000
Other Financial Institutions [Member]
Line of Credit Facility, Maximum Borrowing Capacity	97,000
Federal Home Loan Bank, Advances, Term [Member]
Long-Term Federal Home Loan Bank Advances	20,000
Federal Home Loan Bank, Advances, Putable Option [Member]
Long-Term Federal Home Loan Bank Advances	$ 140,000
Federal Home Loan Bank, Advances, Weighted Average Interest Rate	3.83%
Federal Home Loan Bank Overnight Advances [Member]
Long-Term Federal Home Loan Bank Advances	$ 0
Federal Home Loan Bank Secured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity	1,500,000
Line of Credit Facility, Current Borrowing Capacity	1,400,000
Federal Home Loan Bank Secured Line of Credit [Member] \| Asset Pledged as Collateral [Member]
Financing Receivable, before Allowance for Credit Loss	2,000,000	$ 1,900,000
Federal Home Loan Bank of San Francisco Secured Line of Credit [Member]
Line of Credit Facility, Maximum Borrowing Capacity	69,700
Federal Home Loan Bank of San Francisco Secured Line of Credit [Member] \| Asset Pledged as Collateral [Member]
Financing Receivable, before Allowance for Credit Loss	$ 88,600

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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