Note 7 - Loans - Allowance for Loan Losses by Portfolio Segment and Based on Impairment Method (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Commercial Portfolio Segment [Member]
Loans individually evaluated for impairment, allowance	$ 1,320	$ 530
Loans individually evaluated for impairment, balance	32,631	13,568
Loans collectively evaluated for impairment, allowance	52,379	55,669
Loans collectively evaluated for impairment, balance	2,216,365	2,303,295
Loans, allowance	53,699	56,199
Loans	2,248,996	2,316,863
Real Estate Construction Portfolio Segment [Member]
Loans individually evaluated for impairment, allowance
Loans individually evaluated for impairment, balance	5,507	22,002
Loans collectively evaluated for impairment, allowance	9,245	22,170
Loans collectively evaluated for impairment, balance	509,729	419,541
Loans, allowance	9,245	22,170
Loans	515,236	441,543
Commercial Real Estate Portfolio Segment [Member]
Loans individually evaluated for impairment, allowance	1,248	6,792
Loans individually evaluated for impairment, balance	74,587	81,776
Loans collectively evaluated for impairment, allowance	43,685	42,648
Loans collectively evaluated for impairment, balance	5,669,404	5,219,442
Loans, allowance	44,933	49,440
Loans	5,743,991	5,301,218
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Loans individually evaluated for impairment, allowance	375	427
Loans individually evaluated for impairment, balance	18,189	16,464
Loans collectively evaluated for impairment, allowance	9,682	10,718
Loans collectively evaluated for impairment, balance	2,481,235	2,084,871
Loans, allowance	10,057	11,145
Loans	2,499,424	2,101,335
Consumer Portfolio Segment [Member]
Loans individually evaluated for impairment, allowance
Loans individually evaluated for impairment, balance
Loans collectively evaluated for impairment, allowance	8	9
Loans collectively evaluated for impairment, balance	2,810	2,493
Loans, allowance	8	9
Loans	2,810	2,493
Loans individually evaluated for impairment, allowance	2,943	7,749
Loans individually evaluated for impairment, balance	130,914	133,810
Loans collectively evaluated for impairment, allowance	114,999	131,214
Loans collectively evaluated for impairment, balance	10,879,543	10,029,642
Loans, allowance	117,942	138,963
Loans	$ 11,010,457	$ 10,163,452

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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