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Securities (FY) (Details Textual)	Dec. 31, 2017 USD ($) investment	Dec. 31, 2016 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities pledged as collateral | $	$ 97,160,059	$ 86,351,097
U.S. Government-sponsored enterprises (GSEs) [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions (Number of investments)	6
Muncipal Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions (Number of investments)	13
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions (Number of investments)	1
Mortgage-backed securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Securities in unrealized loss positions (Number of investments)	60

X

- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

+ References

No definition available.

+ Details

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X

- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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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.

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- Details

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- Details

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