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Fair Value Disclosures Fair Value Disclosures - Unobservable Inputs (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |
Impaired loans | $ 620,000 | $ 769,000
Foreclosed assets | $ 2,665,057 | $ 3,254,392
Impaired loans [Member] |  |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |
Valuation techniques | Appraisal | Appraisal
Significant other unobservable input | Appraisal Discounts | Appraisal Discounts
Weighted average of input | 37.00% | 36.00%
Foreclosed assets [Member] |  |
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] |  |
Valuation techniques | Appraisal | Appraisal
Significant other unobservable input | Appraisal Discounts | Appraisal Discounts
Weighted average of input | 21.00% | 18.00%

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- Definition Description of significant assumptions used by management to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 + Details
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- Definition Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524 + Details
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