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Note 6 - Other Assets and Other Liabilities (Details Textual) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2025 USD ($) $ / shares shares	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
LIHTC Investments	$ 32,636		$ 28,551
Investment Program, Proportional Amortization Method, Elected, Commitment	$ 13,417		11,368
Lessee, Operating Lease, Term of Contract	5 years
Lessee, Operating Lease, Renewal Term (Year)	5 years
Operating Lease, Liability	$ 19,992		17,985
Operating Lease, Right-of-Use Asset	$ 19,992		$ 17,985
Operating Lease, Weighted Average Remaining Lease Term (Year)	3 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent	3.57%
Operating Lease, Cost	$ 1,680	$ 1,678
Contingent Commitment, Remainder of Fiscal Year [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	4,905
Contingent Commitment, Year 1 [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	4,688
Contingent Commitment, Year 2 [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	2,569
Contingent Commitment, Year 3 [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	348
Contingent Commitment, Year 4 [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	396
Contingent Commitment, Thereafter [Member]
Investment Program, Proportional Amortization Method, Elected, Commitment	$ 511
Visa Inc. [Member]
Investment Owned, Balance, Shares \| shares	211
Conversion Rate of Class B Common Stock into Class A Common Stock	1.5609
Share Price \| $ / shares	$ 350.46
Visa Inc. [Member] \| Reported Value Measurement [Member]
Investment Owned, Fair Value	$ 0