Note 5 - Loans and Allowance for Credit Losses (Details) - Loans Past Due (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due	$ 4,703	$ 3,502
Loans 60-89 Days Past Due	11,068	13,641
Loans 90 Days or More Past Due	22,443	24,702
Total Past Due Loans	38,214	41,845
Current Loans	4,274,182	2,903,313
Total Recorded Investment in Loans	4,312,399us-gaap_NotesReceivableNet	2,945,158us-gaap_NotesReceivableNet
Commercial Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due	1,505	1,698
Loans 60-89 Days Past Due	4,032	11,146
Loans 90 Days or More Past Due	12,975	6,779
Total Past Due Loans	18,512	19,623
Current Loans	897,714	674,727
Total Recorded Investment in Loans	916,226	694,350
Commercial Real Estate Investment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due	1,825	818
Loans 60-89 Days Past Due	5,376
Loans 90 Days or More Past Due	2,645	2,525
Total Past Due Loans	9,846	3,343
Current Loans	1,693,326	1,116,457
Total Recorded Investment in Loans	1,703,172	1,119,800
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due	1,089	360
Loans 60-89 Days Past Due	214	2,121
Loans 90 Days or More Past Due	1,324	5,452
Total Past Due Loans	2,627	7,933
Current Loans	458,954	309,558
Total Recorded Investment in Loans	461,581	317,491
Real Estate Mortgage Residential [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 90 Days or More Past Due	346	887
Total Past Due Loans	346	887
Current Loans	147,672	89,531
Total Recorded Investment in Loans	148,018	90,418
Home Equity Line of Credit [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due		626
Loans 60-89 Days Past Due	1,365	359
Loans 90 Days or More Past Due	1,398	623
Total Past Due Loans	2,763	1,608
Current Loans	119,773	108,634
Total Recorded Investment in Loans	122,536	110,242
Consumer, Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 30-59 Days Past Due	284
Loans 60-89 Days Past Due	81	15
Loans 90 Days or More Past Due	58	70
Total Past Due Loans	423	85
Current Loans	108,979	3,946
Total Recorded Investment in Loans	109,402	4,031
Construction Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans 90 Days or More Past Due	3,697	8,366
Total Past Due Loans	3,697	8,366
Current Loans	847,767	600,460
Total Recorded Investment in Loans	$ 851,464	$ 608,826

Financing receivables that are less than 60 days past due but more than 29 days past due.

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=35738203&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

Reference 1: 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=35738203&loc=d3e5111-111524

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Financing receivables that are current.

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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Article 5

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