Note 8 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Loans	$ 15,534,212	$ 15,075,481
Less: Allowance for loan losses	(148,273)	(123,224)
Unamortized deferred loan fees, net	(277)	(626)
Loans, net	15,385,662	14,951,631
Commercial Portfolio Segment [Member]
Loans	2,973,078	2,778,744
Less: Allowance for loan losses	(67,799)	(57,021)
Residential Portfolio Segment [Member]
Loans	4,173,876	4,088,586
Commercial Real Estate Portfolio Segment [Member]
Loans	7,422,585	7,275,262
Less: Allowance for loan losses	(39,886)	(33,602)
Real Estate Construction Portfolio Segment [Member]
Loans	577,240	579,864
Less: Allowance for loan losses	(23,222)	(19,474)
Equity Lines Portfolio Segment [Member]
Loans	385,317	347,975
Consumer Portfolio Segment [Member]
Loans	$ 2,116	5,050
Less: Allowance for loan losses		$ (19)

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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