Employee Benefits and Retirement Plans - Amounts Recognized in Comprehensive Income (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Retirement Benefits [Abstract]
Net loss (gain)	$ 40,601	$ (503,167)	$ 110,306
Prior service costs	0	0	0
Total recognized in other comprehensive income (loss)	40,601	(503,167)	110,306
Net periodic pension cost	418,789	583,427	646,160
Partial recognition of loss due to settlement	0	0	426,599
Total recognized in net periodic pension cost and other comprehensive income	$ 459,390	$ (80,260)	$ 1,183,065

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Amount, after tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of tax expense (benefit) for increase (decrease) to other comprehensive income from settlement and curtailment gain (loss) of defined benefit plan.

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