Note 5 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loans	$ 18,254,024	$ 16,342,479
Less: Allowance for loan losses	(146,485)	(136,157)	$ (166,538)
Unamortized deferred loan fees, net	(6,641)	(4,321)
Loans, net	18,100,898	16,202,001
Commercial Portfolio Segment [Member]
Loans	3,318,778	2,982,399
Less: Allowance for loan losses	(49,435)	(43,394)	(68,742)
Real Estate Construction Portfolio Segment [Member]
Loans	559,372	611,031
Less: Allowance for loan losses	(10,417)	(6,302)	(30,854)
Commercial Real Estate Portfolio Segment [Member]
Loans	8,793,685	8,143,272
Less: Allowance for loan losses	(68,366)	(61,081)	(49,205)
Residential Portfolio Segment [Member]
Loans	5,252,952	4,182,006
Equity Lines Portfolio Segment [Member]
Loans	324,548	419,487
Installment and Other Loans [Member ]
Loans	4,689	4,284
Less: Allowance for loan losses	$ (35)	$ (1)	$ 0

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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