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Note 3 - Loans and Allowance for Loan Losses - Nonperforming Loans (Details) - USD ($) | Mar. 31, 2018 | Dec. 31, 2017
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Originated Loan [Member] |  |
Loans past due 90 days or more still accruing interest | $ 0 | $ 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Nonperforming Financial Instruments [Member] |  |
Total nonperforming | 5,742,000 | 7,143,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] |  |
Total nonperforming | 2,604,000 | 3,898,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Total nonperforming | 619,000 | 1,444,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Total nonperforming | 0 | 35,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Total nonperforming | 1,831,000 | 2,241,000
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Total nonperforming | 0 | 0
Nonperforming Financial Instruments [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Total nonperforming | 154,000 | 178,000
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member] |  |
Total nonperforming | 3,138,000 | 3,245,000
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Total nonperforming | 512,000 | 577,000
Nonperforming Financial Instruments [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Total nonperforming | 2,626,000 | 2,668,000
Nonperforming Financial Instruments [Member] | Originated Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Nonaccrual loans | 2,763,000 | 3,672,000
Total nonperforming | 2,763,000 | 3,672,000
Nonperforming Financial Instruments [Member] | Acquired Loan [Member] |  |
Loans past due 90 days or more still accruing interest | 0 | 0
Nonaccrual loans | 2,979,000 | 3,471,000
Total nonperforming | $ 2,979,000 | $ 3,471,000

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- Definition Recorded investment in financing receivables that are 90 days or more past due and still accruing. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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