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Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Number of Days of Delinquent Loans Nonaccrual of Interest | 90 days |  |
Minimum Number of Days of Discontinued Loan Payments for Modified Loan to be Placed on Nonaccrual | 90 days |  |
Number of Days Past Due | 30 days |  |
Threshold for Designation to Impaired Status | $ 250,000 |  |
Minimum Number of Days Consumer Loans are Past Due for Losses to be Charged Off | 120 days |  |
Maximum Number of Days Consumer Loans are Past Due for Losses to be Charged Off | 180 days |  |
Number of Days Loans Secured by Residential Or Commercial Real Estate Are Past Due for Losses to Be Carged Off | 180 days |  |
Period of Time Between Issuance of Loan Commitment and Closing and Sale of Loans Lower Range | 30 days |  |
Period of Time Between Issuance of Loan Commitments and Closing and Sale of Loans Upper Range | 60 days |  |
Noncontrolling Interest, Ownership Percentage by Parent | 100.00% |  |
Goodwill, Impairment Loss | $ 0 | $ 0 | $ 0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 0 | 0 | 0
Advertising Expense | $ 122,000 | $ 105,000 | $ 174,000
Minimum [Member] |  |  |
Finite-Lived Intangible Asset, Useful Life | 10 years |  |
Maximum [Member] |  |  |
Finite-Lived Intangible Asset, Useful Life | 12 years |  |
Building [Member] |  |  |
Property, Plant and Equipment, Useful Life | 40 years |  |
Furniture and Fixtures [Member] | Minimum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |
Furniture and Fixtures [Member] | Maximum [Member] |  |  |
Property, Plant and Equipment, Useful Life | 10 years |  |
Computer Equipment [Member] |  |  |
Property, Plant and Equipment, Useful Life | 3 years |  |

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- Definition Minimum number of days of no loan payments due to loan modification for the loan to be placed on nonaccrual. + References No definition available. + Details
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