Note 7 - Aging of Loan Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Commercial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due	$ 23,122	$ 8,367
Commercial Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due	6,743	221
Commercial Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Commercial Portfolio Segment [Member]
Loans past due	38,116	12,133
Non-accrual loans	8,251	3,545
Loans not past due	2,149,931	2,304,730
Loans	2,188,047	2,316,863
Real Estate Construction Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due		7,285
Real Estate Construction Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due
Real Estate Construction Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Real Estate Construction Portfolio Segment [Member]
Loans past due	6,081	23,591
Non-accrual loans	6,081	16,306
Loans not past due	475,739	417,952
Loans	481,820	441,543
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due	5,272	2,243
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due	3,008	2,223
Commercial Real Estate Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Commercial Real Estate Portfolio Segment [Member]
Loans past due	39,005	29,697
Non-accrual loans	30,725	25,231
Loans not past due	5,492,181	5,271,521
Loans	5,531,186	5,301,218
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due	242	4,959
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due	378	1,038
Residential Mortgage and Equity Lines Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Residential Mortgage and Equity Lines Portfolio Segment [Member]
Loans past due	8,701	13,045
Non-accrual loans	8,081	7,048
Loans not past due	2,310,166	2,088,290
Loans	2,318,867	2,101,335
Consumer Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due
Consumer Portfolio Segment [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due
Consumer Portfolio Segment [Member] \| Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Consumer Portfolio Segment [Member]
Loans past due
Non-accrual loans
Loans not past due	3,180	2,493
Loans	3,180	2,493
Financing Receivables, 30 to 59 Days Past Due [Member]
Loans past due	28,636	22,854
Financing Receivables, 60 to 89 Days Past Due [Member]
Loans past due	10,129	3,482
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Loans past due
Loans past due	91,903	78,466
Non-accrual loans	53,138	52,130
Loans not past due	10,431,197	10,084,986
Loans	$ 10,523,100	$ 10,163,452

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953401-111524

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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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