Income Taxes - Significant Components of Deferred Tax Assets and Liabilities (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Net operating loss and tax credit carryforwards	$ 72,201,754	$ 66,867,637
Capital loss carryforward	5,514	5,683
Accrued expenses	363,149	253,374
Start-up costs	5,664	5,837
Excess of book over tax depreciation	259,667	394,649
Stock option and restricted stock award expense	1,429,488	1,464,210
Debt Extinguishment	58,161	59,934
Less: valuation allowance	(74,138,667)	(68,859,984)	$ (68,859,984)
Deferred tax assets	184,730	191,340
Deferred tax liability:
Property and equipment basis	10,434	48,545
Prepaid expenses	174,296	142,795
Deferred tax liabilities	184,730	191,340
Net deferred tax asset	$ 0	$ 0

Deferred tax assets debt extinguishment

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Deferred tax assets net operating loss and capital loss carryforwards.

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Deferred tax assets start up costs.

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Deferred tax assets tax deferred expense reserves and accruals accrued expenses.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax consequences attributable to taxable temporary differences derived from prepaid expenses.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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