Note 4 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Loans	$ 15,644,396	$ 15,075,481
Less: Allowance for loan losses	(166,538)	(123,224)
Unamortized deferred loan fees, net	(2,494)	(626)
Loans, net	15,475,364	14,951,631
Commercial Portfolio Segment [Member]
Loans	2,836,833	2,778,744
Less: Allowance for loan losses	(68,742)	(57,021)
Real Estate Construction Portfolio Segment [Member]
Loans	679,492	579,864
Less: Allowance for loan losses	(30,854)	(19,474)
Commercial Real Estate Portfolio Segment [Member]
Loans	7,555,027	7,275,262
Less: Allowance for loan losses	(49,205)	(33,602)
Residential Portfolio Segment [Member]
Loans	4,145,389	4,088,586
Equity Lines Portfolio Segment [Member]
Loans	424,555	347,975
Consumer Portfolio Segment [Member]
Loans	$ 3,100	$ 5,050

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 before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes 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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