Note 8 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Loans	$ 15,651,848	$ 15,644,396
Less: Allowance for loan losses	(147,264)	(166,538)
Unamortized deferred loan fees, net	(6,872)	(2,494)
Loans, net	15,497,712	15,475,364
Commercial Portfolio Segment [Member]
Loans	2,890,693	2,836,833
Less: Allowance for loan losses		(68,742)
Residential Portfolio Segment [Member]
Loans	4,102,203	4,145,389
Commercial Real Estate Portfolio Segment [Member]
Loans	7,549,522	7,555,027
Less: Allowance for loan losses		(49,205)
Real Estate Construction Portfolio Segment [Member]
Loans	677,816	679,492
Less: Allowance for loan losses		(30,854)
Equity Lines Portfolio Segment [Member]
Loans	428,318	424,555
Installment and Other Loans [Member ]
Loans	$ 3,296	$ 3,100

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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