Note 4 - Loans and the Allowance for Credit Losses - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	$ 8,351,841	$ 8,109,161
Net deferred fees	(6,696)	(9,472)
Loans receivable	8,345,145	8,099,689
Commercial Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	1,578,730	1,472,734
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	5,895,545	5,795,228
Commercial Construction Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	620,496	574,139
Residential Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	256,041	264,748
Consumer Portfolio Segment [Member]
Financing Receivable, before Allowance for Credit Loss, Fee and Loan in Process	$ 1,029	$ 2,312

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