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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 |

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- Definition The fair value of available-for-sale securities that serve as collateral for borrowings. + References No definition available. + Details
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- 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 + Details
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