Note 8 - Loans - Components of Loans in Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Loans	$ 13,014,539	$ 12,870,290
Less: Allowance for loan losses	(122,084)	(123,279)
Unamortized deferred loan fees, net	(3,289)	(3,245)
Total loans, net	12,889,166	12,743,766
Loans held for sale		8,000
Commercial Portfolio Segment [Member]
Loans	2,436,421	2,461,266
Less: Allowance for loan losses	(54,597)	(49,796)
Residential Portfolio Segment [Member]
Loans	3,198,750	3,062,050
Commercial Real Estate Portfolio Segment [Member]
Loans	6,610,254	6,482,695
Less: Allowance for loan losses	(34,230)	(37,610)
Real Estate Construction Portfolio Segment [Member]
Loans	587,927	678,805
Less: Allowance for loan losses	(21,864)	(24,838)
Equity Lines Portfolio Segment [Member]
Loans	176,714	180,304
Consumer Portfolio Segment [Member]
Loans	4,473	5,170
Less: Allowance for loan losses	$ (21)	$ (22)

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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