Note 8 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Loans	$ 14,728,554	$ 13,995,788
Less: Allowance for loan losses	(125,908)	(122,391)
Unamortized deferred loan fees, net	(1,081)	(1,565)
Total loans, net	14,601,565	13,871,832
Loans held for sale	36,778	0
Commercial Portfolio Segment [Member]
Loans	2,668,061	2,741,965
Less: Allowance for loan losses	(58,549)	(54,978)
Residential Portfolio Segment [Member]
Loans	4,010,739	3,693,853
Commercial Real Estate Portfolio Segment [Member]
Loans	7,135,599	6,724,200
Less: Allowance for loan losses	(33,467)	(33,487)
Equity Lines Portfolio Segment [Member]
Loans	315,252	249,967
Real Estate Construction Portfolio Segment [Member]
Loans	593,816	581,454
Less: Allowance for loan losses	(21,698)	(19,626)
Consumer Portfolio Segment [Member]
Loans	5,087	4,349
Less: Allowance for loan losses	$ (25)	$ (18)

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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