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Loans and Allowance for Loan Losses (FY) (Details Textual) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 USD ($) Loan | Dec. 31, 2017 USD ($) contract | Jun. 30, 2018 USD ($) | Dec. 31, 2016 USD ($)
Financing Receivable, Modifications [Line Items] |  |  |  |
Nonaccrual | $ 1,764,000 | $ 1,764,000 | $ 1,538,000 | $ 1,415,000
Number of Contracts | 0 | 0 |  |
Number of loans modified as troubled debt restructurings with subsequent default | contract |  | 0 |  |
Allowance for loan losses | $ 16,000 | $ 16,000 | $ 19,000 |
Pre-approved unused lines of credit with related parties | 5,833,000 | 5,833,000 |  |
Trouble Debt Restructuring [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Troubled debt restructuring | 41,000 | 41,000 |  | 608,000
Nonaccrual | 0 | 0 |  | 442,000
Purchased Credit Impaired Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Allowance for loan losses | $ 16,000 | $ 16,000 |  | $ 0

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- Definition Reserve for loans impairments recorded after acquisition as a result of current information and events which result in it being probable that estimated cash flows will be less than previously expected or because actual cash flows are less than cash flows previously expected. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that was acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524 + Details
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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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