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Loans and Allowance for Loan Losses - Narrative (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2018 USD ($) loan segment	Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Loan portfolio segments | segment	5
Number of contracts | contract		0
Foreclosed assets	$ 4,230,451	$ 3,254,392
Trouble Debt Restructuring [Member]
Financing Receivable, Modifications [Line Items]
Loans that met criteria for restructured	$ 693,000	$ 41,000
Number of contracts, nonaccrual | loan	0
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Foreclosed assets	$ 425,000
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans that met criteria for restructured	$ 622,000
Number of contracts | loan	1
Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans that met criteria for restructured	$ 34,000
Number of contracts | loan	1

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-Topic 310
-SubTopic 10
-Section 50
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