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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans and Associated Reserves (Details) - USD ($) | Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2015
--- | --- | --- | ---
Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member] |  |  |  |  |  |
Principal Balance | [1] | $ 689,000 |  | $ 718,000 |  |
Total impaired loans | [1],[2] | 682,000 |  | 718,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 682,000 |  | 718,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [1] | 0 |  | 0 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End First Liens [Member] |  |  |  |  |  |
Principal Balance | [1] | 708,000 |  | 713,000 |  |
Total impaired loans | [1],[2] | 664,000 |  | 669,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 303,000 |  | 305,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 361,000 |  | 364,000 |  |
Related Allowance | [1] | 13,000 |  | 13,000 |  |
Consumer Real Estate Portfolio Segment [Member] | Closed End Junior Liens [Member] |  |  |  |  |  |
Principal Balance | [1] | 214,000 |  | 218,000 |  |
Total impaired loans | [1],[2] | 214,000 |  | 218,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 0 |  | 0 |  |
Impaired loans with a valuation allowance | [1],[2] | 214,000 |  | 218,000 |  |
Related Allowance | [1] | 5,000 |  | 5,000 |  |
Consumer Real Estate Portfolio Segment [Member] | Investor Owned Residential Real Estate [Member] |  |  |  |  |  |
Principal Balance | [1] | 75,000 |  | 75,000 |  |
Total impaired loans | [1],[2] | 75,000 |  | 75,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 0 |  | 0 |  |
Impaired loans with a valuation allowance | [1],[2] | 75,000 |  | 75,000 |  |
Related Allowance | [1] | 4,000 |  | 4,000 |  |
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |  |  |  |
Principal Balance | [1] | 1,867,000 |  | 1,988,000 |  |
Total impaired loans | [1],[2] | 1,594,000 |  | 1,728,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 1,594,000 |  | 1,728,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [1] | 0 |  | 0 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |  |  |  |
Principal Balance | [1] | 4,213,000 |  | 5,068,000 |  |
Total impaired loans | [1],[2] | 4,165,000 |  | 5,020,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 2,997,000 |  | 3,304,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 1,168,000 |  | 1,716,000 |  |
Related Allowance | [1] | 58,000 |  | 23,000 |  |
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] |  |  |  |  |  |
Principal Balance | [1] | 5,966,000 |  | 5,990,000 |  |
Total impaired loans | [1],[2] | 5,778,000 |  | 5,827,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 5,778,000 |  | 5,827,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [1] | 0 |  | 0 |  |
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member] |  |  |  |  |  |
Principal Balance | [1] | 824,000 |  | 1,099,000 |  |
Total impaired loans | [1],[2] | 817,000 |  | 1,091,000 |  |
Impaired loans with no valuation allowance | [1],[2] | 817,000 |  | 1,091,000 |  |
Impaired loans with a valuation allowance | [1],[2] | 0 |  | 0 |  |
Related Allowance | [1] | 0 |  | 0 |  |
Principal Balance | [1] | 14,556,000 |  | 15,869,000 |  |
Total impaired loans |  | 13,989,000 | [1],[2] | 15,346,000 | [1],[2] | $ 14,994,000
Impaired loans with no valuation allowance |  | 12,171,000 | [1],[2] | 12,973,000 | [1],[2] | 11,265,000
Impaired loans with a valuation allowance |  | 1,818,000 | [1],[2] | 2,373,000 | [1],[2] | 3,729,000
Related Allowance |  | $ 80,000 | [1] | $ 45,000 | [1] | $ 236,000
[1] | Only classes with impaired loans are shown.
[2] | Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.

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- Definition 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 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + 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 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
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