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Fair Value of Assets and Liabilities (FY) (Details 2) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Jun. 30, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Impaired loans | $ 769,000 | $ 239,000 | $ 407,000
Foreclosed assets | $ 3,254,392 | $ 2,386,239 | $ 3,524,239
Impaired Loans [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Valuation Technique | Third Party Appraisal | Cash Flow |
Significant Other Unobservable Input | Appraisal Discounts | Discounted Cash Flow / Appraisal Discounts |
Weighted Average of Input (as a percent) | 35.50% | 2.40% |
Foreclosed assets [Member] |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Valuation Technique | Third Party Appraisal | Appraisal |
Significant Other Unobservable Input | Appraisal Discounts | Appraisal Discounts |
Weighted Average of Input (as a percent) | 17.80% | 12.20% |

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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://fasb.org/us-gaap/role/ref/legacyRef -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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -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 + Details
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