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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Past Due and Nonaccrual Loans (Details) - USD ($) | Jun. 30, 2016 | Dec. 31, 2015 | Jun. 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 |  | 1,229,000 | [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 |  | 21,000 | [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 |  | 242,000 | [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 |  | 330,000 | [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 |  | 0 | [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 Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans |  | 45,000 | [1] | 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 |  | 18,000 | [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 |  | 237,000 | [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 |  | 49,000 | [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 |  | 2,208,000 | [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 |  | 48,000 | [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 |  | 216,000 | [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 |  | 12,000 | [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 |  | 1,594,000 | [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 |  | 610,000 | [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 Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
Past due loans |  | 315,000 | [1] | 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 |  | 4,000 | [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 |  | 11,000 | [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 |  | 0 | [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 |  | 2,847,000 | [1] | 3,124,000 |
Real Estate Construction Portfolio Segment[Member] | Construction Residential [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 678,000 | [1] | 718,000 |
Real Estate Construction Portfolio Segment[Member] | Construction Other [Member] |  |  |  |  |
90 or more days past due and still accruing |  |  |  | 0 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 0 |
Consumer Real Estate Portfolio Segment [Member] | Equity Lines [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 48,000 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 216,000 | [1] | 106,000 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 14,000 |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |
90 or more days past due 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] |  |  |  |  |
90 or more days past due and still accruing |  |  | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 22,000 | [1] | 0 |
Consumer Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
Nonaccruals (including impaired nonaccruals) | [1] | 0 |  |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] |  |
Nonaccruals (including impaired nonaccruals) |  | 1,594,000 | [1] | 1,728,000 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] |  |
Nonaccruals (including impaired nonaccruals) |  | 737,000 | [1] | 494,000 |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 2,774,000 | [1] | 2,845,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 400,000 | [1] | 883,000 |
Consumer Non Real Estate Portfolio Segment [Member] | Credit Card Receivable [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 4,000 | [1] | 6,000 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 0 |
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 11,000 | [1] | 5,000 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Consumer Non Real Estate Portfolio Segment [Member] | Other Consumer Loans [Member] |  |  |  |  |
90 or more days past due and still accruing |  | 0 | [1] | 0 |
Nonaccruals (including impaired nonaccruals) |  | 0 | [1] | 0 |
Public Sector and IDA Portfolio Segment[Member] |  |  |  |  |
90 or more days past due and still accruing |  |  |  | 0 |
Nonaccruals (including impaired nonaccruals) |  |  |  | 0 |
90 or more days past due and still accruing |  | 316,000 | [1] | 156,000 | $ 80,000
Nonaccruals (including impaired nonaccruals) |  | $ 6,205,000 |  | $ 6,682,000 | $ 8,905,000
[1] | Only classes with past-due or nonaccrual loans are shown.

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