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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

X

- 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.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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