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Securities - Narrative (Details)	3 Months Ended		9 Months Ended
Securities - Narrative (Details)	Sep. 30, 2018 USD ($) investment	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) investment	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Loans and Leases Receivable Disclosure [Line Items]
Proceeds from sale of available-for-sale securities \| $	$ 0	$ 12,363,748		$ 12,363,748
Loss from redemption of securities \| $		1,780	$ 1,200	1,780
Gross realized gains, available for sale \| $		$ 145,288		$ 145,288
Collateral Pledged [Member]
Loans and Leases Receivable Disclosure [Line Items]
Restricted securities \| $	$ 109,500,000		$ 109,500,000		$ 97,200,000
US Government-sponsored Enterprises Debt Securities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of positions \| investment	8		8
Municipal securities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of positions \| investment	32		32
Other debt securities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of positions \| investment	1		1
Mortgage-backed securities [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of positions \| investment	66		66