Note 9 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Loans	$ 17,398,357	$ 16,342,479
Less: Allowance for loan losses	(145,786)	(136,157)
Unamortized deferred loan fees, net	(4,679)	(4,321)
Loans, net	17,247,892	16,202,001
Commercial Portfolio Segment [Member]
Loans	3,125,151	2,982,399
Residential Portfolio Segment [Member]
Loans	4,834,782	4,182,006
Commercial Real Estate Portfolio Segment [Member]
Loans	8,401,742	8,143,272
Real Estate Construction Portfolio Segment [Member]
Loans	631,740	611,031
Equity Lines Portfolio Segment [Member]
Loans	398,851	419,487
Installment and Other Loans [Member ]
Loans	$ 6,091	$ 4,284

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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