Pension and Profit Sharing - Amounts Recognized in Other Comprehensive Income (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Compensation And Retirement Disclosure [Abstract]
Balance at beginning of the year	$ 689,936	$ 689,936	$ 881,452
Change in net loss	(617,800)	(100,530)
Amortization of actuarial loss	(71,598)	(90,442)
Amortization of prior service cost	(538)	(544)
Change recognized in other comprehensive income	(689,936)	(191,516)
Amounts recognized in accumulated other comprehensive income:
Net actuarial loss		689,398
Prior service cost		538
Total:	$ 689,936	$ 689,936	$ 881,452

Change in net loss recorded in other comprehensive income related to benefit costs.

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, after tax, of accumulated other comprehensive (income) loss for 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, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income from prior service cost (credit) of defined benefit plan.

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

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