Note 8 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans	$ 12,597,434	$ 11,201,275
Less: Allowance for loan losses	(121,535)	(118,966)
Unamortized deferred loan fees, net	(3,424)	(4,994)
Total loans, net	12,472,475	11,077,315
Loans held for sale		7,500
Commercial Portfolio Segment [Member]
Loans	2,419,891	2,248,187
Less: Allowance for loan losses	(51,039)	(49,203)
Residential Portfolio Segment [Member]
Loans	2,922,537	2,444,048
Commercial Real Estate Portfolio Segment [Member]
Loans	6,377,047	5,785,248
Less: Allowance for loan losses	(37,402)	(34,864)
Real Estate Construction Portfolio Segment [Member]
Loans	691,486	548,088
Less: Allowance for loan losses	(22,008)	(23,268)
Equity Lines Portfolio Segment [Member]
Loans	181,751	171,711
Consumer Portfolio Segment [Member]
Loans	4,722	3,993
Less: Allowance for loan losses	$ (24)	$ (11)

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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