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Note 9 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Loans	$ 18,106,803		$ 16,342,479
Less: Allowance for loan losses	(148,817)	$ (148,772)	(136,157)	$ (131,945)	$ (131,256)	$ (166,538)
Unamortized deferred loan fees, net	(6,936)		(4,321)
Loans, net	17,951,050		16,202,001
Commercial Portfolio Segment [Member]
Loans	3,367,437		2,982,399
Less: Allowance for loan losses	(50,399)	(49,069)	(43,394)	(38,213)	(40,067)	(68,742)
Real Estate Construction Portfolio Segment [Member]
Loans	573,421		611,031
Less: Allowance for loan losses	(6,211)	(7,276)	(6,302)	(6,344)	(6,119)	(30,854)
Commercial Real Estate Portfolio Segment [Member]
Loans	8,677,733		8,143,272
Less: Allowance for loan losses	(70,050)	(68,600)	(61,081)	(60,956)	(58,026)	(49,205)
Residential Portfolio Segment [Member]
Loans	5,130,650		4,182,006
Equity Lines Portfolio Segment [Member]
Loans	350,448		419,487
Installment and Other Loans [Member ]
Loans	7,114		4,284
Less: Allowance for loan losses	$ (128)	$ (135)	$ (1)	$ (1)	$ (1)	$ 0