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Fair Value Disclosures - Fair Value Disclosures - Unobservable Inputs (Q2) (Details) | Jun. 30, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
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Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Impaired loans | $ 407,000 | $ 769,000 | $ 239,000
Foreclosed assets | 3,524,239 | 3,254,392 | 2,386,239
Level 3 [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Impaired loans | $ 407,000 | $ 769,000 | $ 239,000
Weighted Average [Member] | Level 3 [Member] |  |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |  |
Impaired loans, measurement input | 0.47 | 0.36 |
Foreclosed assets, measurement input | 0.19 | 0.18 |

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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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