Employee Benefit Plans - Summary of Change in Plan Assets (Detail) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Pension Plan [Member]
Change in Plan Assets
Fair value of plan assets at beginning of year		$ 52,203,372
Actual return on plan assets		(113,981)
Employer contribution		213,532
Settlements		(52,057,333)
Benefits paid		(245,590)
Supplemental Employee Retirement Plan [Member]
Change in Plan Assets
Employer contribution	$ 367,989	356,354
Benefits paid	(367,989)	(356,354)
Funded status	(9,723,866)	(9,038,825)
Unrecognized net actuarial (gain) loss	593,326	(119,402)
Cumulative employer contributions in excess of the net periodic pension cost	$ (9,130,540)	$ (9,158,227)

Cumulative employer contributions in excess of net periodic benefit cost.

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- Definition

Amount, before 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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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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- Definition

Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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