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Note 3 - Loans and Allowance for Loan Losses - Loans Modified As Troubled Debt Restructurings Within the Previous Twelve Months That Became Over 30 Days Past Due (Details) | 3 Months Ended
--- | ---
Mar. 31, 2018 USD ($) | Mar. 31, 2017 USD ($)
Originated Loan [Member] |  |
Number of Contracts | 1 | 3
Recorded Principal Balance | $ 251,000 | $ 164,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |
Number of Contracts | 1 | 3
Recorded Principal Balance | $ 251,000 | $ 164,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Number of Contracts | 0 | 2
Recorded Principal Balance | $ 0 | $ 34,000
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Number of Contracts | 1 | 0
Recorded Principal Balance | $ 251,000 | $ 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Number of Contracts | 0 | 1
Recorded Principal Balance | $ 0 | $ 130,000
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Acquired Loan [Member] |  |
Number of Contracts | 3 | 1
Recorded Principal Balance | $ 133,000 | $ 24,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |
Number of Contracts | 1 | 1
Recorded Principal Balance | $ 113,000 | $ 24,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |
Number of Contracts | 1 | 1
Recorded Principal Balance | $ 113,000 | $ 24,000
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |
Number of Contracts | 2 | 0
Recorded Principal Balance | $ 20,000 | $ 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Number of Contracts | 2 | 0
Recorded Principal Balance | $ 20,000 | $ 0
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Number of Contracts | 0 | 0
Recorded Principal Balance | $ 0 | $ 0

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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
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