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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Past Due and Nonaccrual Loans (Details) - USD ($) | Sep. 30, 2016 | Dec. 31, 2015 | Sep. 30, 2015
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Financing Receivables 30 to 89 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member] |  |  |  |  |
Past due loans |  | $ 0 | [1] | $ 0 |
Financing Receivables 30 to 89 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Other [Member] |  |  |  |  |
Past due loans |  |  |  | 26,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |
Past due loans |  | 37,000 | [1] | 16,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Past due loans |  | 801,000 | [1] | 1,402,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |
Past due loans |  | 117,000 | [1] | 123,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Past due loans |  | 239,000 | [1] | 248,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |
Past due loans |  | 318,000 | [1] | 684,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Past due loans |  | 127,000 | [1] | 0 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
Past due loans |  | 0 | [1] | 0 |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans | [1] | 66,000 |  |  |
Financing Receivables 30 to 89 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans |  |  |  | 142,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Past due loans |  | 3,000 | [1] | 5,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Past due loans |  | 225,000 | [1] | 286,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Past due loans |  | 74,000 | [1] | 60,000 |
Financing Receivables 30 to 89 Days Past Due [Member] | Public Sector and IDA Portfolio Segment[Member] |  |  |  |  |
Past due loans |  |  |  | 0 |
Financing Receivables 30 to 89 Days Past Due [Member] |  |  |  |  |
Past due loans |  | 2,007,000 | [1] | 2,992,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member] |  |  |  |  |
Past due loans |  | 0 | [1] | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Real Estate Construction Portfolio Segment[Member] | Construction Other [Member] |  |  |  |  |
Past due loans |  |  |  | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |
Past due loans |  | 0 | [1] | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Past due loans |  | 181,000 | [1] | 106,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |
Past due loans |  | 37,000 | [1] | 39,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Past due loans |  | 0 | [1] | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |
Past due loans |  | 1,459,000 | [1] | 1,728,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Past due loans |  | 455,000 | [1] | 357,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
Past due loans |  | 0 | [1] | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans | [1] | 335,000 |  |  |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans |  |  |  | 883,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Past due loans |  | 11,000 | [1] | 6,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Past due loans |  | 6,000 | [1] | 5,000 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Past due loans |  | 4,000 | [1] | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] | Public Sector and IDA Portfolio Segment[Member] |  |  |  |  |
Past due loans |  |  |  | 0 |
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] |  |  |  |  |
Past due loans |  | 2,488,000 | [1] | 3,124,000 |
Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 273,000 | [1] | 718,000 |
Real Estate Construction Portfolio Segment[Member] | Construction Other [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  |  |  | 0 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 0 |
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 137,000 | [1] | 106,000 |
Nonaccruals (including impaired nonaccruals) |  | 44,000 | [1] | 14,000 |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 37,000 | [1] | 39,000 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 19,000 | [1] | 0 |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 1,459,000 | [1] | 1,728,000 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 574,000 | [1] | 494,000 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 2,760,000 | [1] | 2,845,000 |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing | [1] | 0 |  |  |
Nonaccruals (including impaired nonaccruals) | [1] | 361,000 |  |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  |  |  | 0 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 883,000 |
Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 11,000 | [1] | 6,000 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 6,000 | [1] | 5,000 |
Nonaccruals (including impaired nonaccruals) |  | 3,000 | [1] | 0 |
Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  | 4,000 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Public Sector and IDA Portfolio Segment[Member] |  |  |  |  |
Loans past due 90 days or more and still accruing |  |  |  | 0 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 0 |
Loans past due 90 days or more and still accruing |  | 195,000 | [1] | 156,000 | $ 47,000
Nonaccruals (including impaired nonaccruals) |  | $ 5,493,000 | [1] | $ 6,682,000 | $ 8,988,000
[1] | Only classes with past-due or nonaccrual loans are shown.

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- Definition 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 -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 + Details
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