Note 5 - Loans and Allowance for Credit Losses (Details) - Impaired Loans (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	$ 37,420	$ 32,946
Recorded Investment With No Allowance	20,454	9,892
Recorded Investment With Allowance	15,491	22,754
Total Recorded Investment	35,945	32,646
Related Allowance	8,064	6,520
Commercial Loan [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	14,203	8,193
Interest Income Recognized	20	53
Commercial Loan [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	13,681	8,877
Interest Income Recognized	251	131
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	14,075	6,779
Recorded Investment With No Allowance	1,603	2,327
Recorded Investment With Allowance	11,372	4,452
Total Recorded Investment	12,975	6,779
Related Allowance	5,334	1,323
Commercial Real Estate Investment [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	8,202	6,183
Interest Income Recognized	196	38
Commercial Real Estate Investment [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	7,021	5,755
Interest Income Recognized	203	175
Commercial Real Estate Investment [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	10,869	5,902
Recorded Investment With No Allowance	8,952	1,322
Recorded Investment With Allowance	1,542	4,580
Total Recorded Investment	10,494	5,902
Related Allowance	751	1,098
Commercial Real Estate Owner Occupied [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	2,696	5,939
Interest Income Recognized		52
Commercial Real Estate Owner Occupied [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	3,986	6,285
Interest Income Recognized	6	108
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,889	5,452
Recorded Investment With No Allowance	1,038	111
Recorded Investment With Allowance	851	5,341
Total Recorded Investment	1,889	5,452
Related Allowance	577	1,853
Residential Mortgage [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	348	891
Interest Income Recognized		2
Residential Mortgage [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	529	792
Interest Income Recognized		2
Residential Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	346	887
Recorded Investment With No Allowance	346	774
Recorded Investment With Allowance		113
Total Recorded Investment	346	887
Related Allowance		27
Home Equity Line of Credit [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	993	567
Interest Income Recognized	32	2
Home Equity Line of Credit [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	747	508
Interest Income Recognized	36	4
Home Equity Line of Credit [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,398	623
Recorded Investment With No Allowance	339
Recorded Investment With Allowance	1,059	623
Total Recorded Investment	1,398	623
Related Allowance	430	526
Consumer, Other [Member] \| Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	29	58
Interest Income Recognized	7	1
Consumer, Other [Member] \| Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	30	34
Interest Income Recognized	7	2
Consumer, Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	58	70
Recorded Investment With Allowance	58	70
Total Recorded Investment	58	70
Related Allowance	45	68
Quarter to Date [Member] \| Construction Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	10,113	13,405
Interest Income Recognized	436	44
Quarter to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	36,584	35,236
Interest Income Recognized	691	192
Year to Date [Member] \| Construction Loans [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	10,967	17,298
Interest Income Recognized	1,147	169
Year to Date [Member]
Financing Receivable, Impaired [Line Items]
Average Recorded Investment	36,961	39,549
Interest Income Recognized	1,650	591
Construction Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	8,785	13,233
Recorded Investment With No Allowance	8,176	5,358
Recorded Investment With Allowance	609	7,575
Total Recorded Investment	8,785	12,933
Related Allowance	$ 927	$ 1,625

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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