Note 2 - Available-for-sale Securities (Details Textual) - USD ($) |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Dec. 31, 2017 |
|
| Proceeds from Sale of Available-for-sale Securities, Total | $ 0 | $ 0 | |
| Available-for-sale Securities, Greater than 10% of Stockholders' Equity | 0 | $ 0 | |
| Available-for-sale Securities, Total | 26,095,660 | 24,399,881 | |
| Other than Temporary Impairment Losses, Investments, Available-for-sale Securities, Total | 0 | ||
| Loans and Securities Pledged to Secure FHLB Advances | 117,600,000 | ||
| Loans and Securities Pledged to Secure Public Deposits | 4,500,000 | ||
| Collateralized Mortgage Backed Securities [Member] | |||
| Available-for-sale Securities, Total | 10,800,000 | 10,000,000 | |
| Commercial Mortgage Backed Securities [Member] | |||
| Available-for-sale Securities, Total | $ 0 | $ 0 | |