Note 5 - Loans and Allowance for Credit Losses - Recorded Investment in Loans by Impairment Method (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Recorded investment in loans:
Loans individually evaluated for impairment	$ 34,471	$ 31,516
Loans collectively evaluated for impairment	5,643,422	4,966,852
Net loans	5,677,893	4,998,368
Commercial Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	10,437	13,008
Loans collectively evaluated for impairment	1,190,291	1,039,249
Net loans	1,200,728	1,052,257
Income Producing Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	15,057	6,118
Loans collectively evaluated for impairment	2,494,460	2,109,360
Net loans	2,509,517	2,115,478
Owner Occupied Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	2,093	1,753
Loans collectively evaluated for impairment	638,777	496,350
Net loans	640,870	498,103
Residential Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	241
Loans collectively evaluated for impairment	152,507	147,365
Net loans	152,748	147,365
Construction Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	6,517	10,454
Loans collectively evaluated for impairment	1,052,052	1,054,922
Net loans	1,058,569	1,065,376
Home Equity Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment		161
Loans collectively evaluated for impairment	105,096	112,724
Net loans	105,096	112,885
Other Consumer Portfolio Segment [Member]
Recorded investment in loans:
Loans individually evaluated for impairment	126	22
Loans collectively evaluated for impairment	10,239	6,882
Net loans	$ 10,365	$ 6,904

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- Definition

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

+ 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 (h)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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- Definition

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

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

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