Note 4 - Loans (Details) - Aging of the Recorded Investment in Loans - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	$ 3,226	$ 1,704
Total past due loan & nonaccrual loans	4,380	3,890
Current	2,098,509	1,800,929
Total loans	2,102,889	1,804,819
Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due	1,002	2,087
Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due	152	99
Commercial Portfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	65
Total past due loan & nonaccrual loans	71
Current	85,269	77,140
Total loans	85,340	77,140
Commercial Portfolio Segment [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due	6
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	1,883	303
Total past due loan & nonaccrual loans	1,883	1,257
Current	554,235	527,836
Total loans	556,118	529,093
Commercial Real Estate Portfolio Segment [Member] \| Multifamily Loan [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due		954
Commercial Real Estate Portfolio Segment [Member] \| Other Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	296,452	222,537
Total loans	296,452	222,537
Commercial Real Estate Portfolio Segment [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	602	630
Total past due loan & nonaccrual loans	602	630
Current	101,199	106,715
Total loans	101,801	107,345
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	348	395
Total past due loan & nonaccrual loans	1,496	1,454
Current	971,027	778,540
Total loans	972,523	779,994
Residential Portfolio Segment [Member] \| Home Equity Loan [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due	996	1,059
Residential Portfolio Segment [Member] \| Home Equity Loan [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due	152
Residential Portfolio Segment [Member] \| Revolving Home Equity Line [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual loans	328	376
Total past due loan & nonaccrual loans	328	549
Current	84,478	82,560
Total loans	84,806	83,109
Residential Portfolio Segment [Member] \| Revolving Home Equity Line [Member] \| Financing Receivables, 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due		74
Residential Portfolio Segment [Member] \| Revolving Home Equity Line [Member] \| Financing Receivables, 60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past due		99
Consumer and Other Porfolio Segment [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current	5,849	5,601
Total loans	$ 5,849	$ 5,601

Recorded Investment in financing receivables that are total of past due and nonaccruals at the balance sheet date.

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- Definition

Financing receivables that are current.

+ References

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=49124121&loc=SL6953401-111524

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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No definition available.

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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=28367877&loc=d3e4428-111522

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