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Concentrations of Credit Risk (Details Textual) | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016
Concentration Risk [Line Items] |  |
Credit extending terms to borrowers | The Bank, as a matter of policy, does not generally extend credit to any single borrower or group of related borrowers in excess of 25% of statutory capital, or approximately $42,325,000. |
Commercial Real Estate [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk (as a percent) | 56.00% | 61.00%
Loan Portfolio Secured by Real Estate [Member] |  |
Concentration Risk [Line Items] |  |
Concentration risk (as a percent) | 81.00% |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6404-108592 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611 + Details
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