Note 5 - Loans and the Allowance for Credit Losses - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Gross loans	$ 8,304,101	$ 8,351,841
Net deferred loan fees	(6,144)	(6,696)
Total loans receivable	8,297,957	8,345,145
Commercial Portfolio Segment [Member]
Gross loans	1,572,494	1,578,730
Commercial Real Estate Portfolio Segment [Member]
Gross loans	5,829,950	5,895,545
Commercial Construction Portfolio Segment [Member]
Gross loans	646,593	620,496
Residential Portfolio Segment [Member]
Gross loans	254,214	256,041
Consumer Portfolio Segment [Member]
Gross loans	$ 850	$ 1,029

Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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+ Details