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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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Weighted average rate of the fair value input.

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Description of significant assumptions used by management to measure fair value.

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Description of the inputs and valuation technique(s) used to measure fair value.

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Representing impaired loans fair value disclosure.

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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

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