Class of warrant or right exercise price of warrants or rights 2.

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Number of assets.

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Significant accounting policies.

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Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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Fair value portion of assets, excluding financial assets and goodwill, that lack physical substance, having a projected indefinite period of benefit.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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No definition available.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Amount of lessee's right to use underlying asset under operating lease.

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-SubTopic 20
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-Paragraph 1
-Subparagraph (a)
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Percentage of fair value of reporting unit in excess of carrying amount.

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No definition available.

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Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended	12 Months Ended
	Dec. 31, 2018 USD ($) Asset $ / shares	Dec. 31, 2018 USD ($) Segment Asset $ / shares	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($)	Oct. 10, 2018 $ / shares	Mar. 09, 2017 $ / shares	Dec. 31, 2016 USD ($)
Significant Accounting Policies [Line Items]
Number of operating segments \| Segment		1
Carrying value of assets	$ 38,872,537	$ 38,872,537	$ 39,209,211
Goodwill impairment charges		490,676	35,919,695
Fair value transfers, Level 1 to Level 2 assets			0				$ 0
Fair value transfers, Level 2 to Level 1 assets			0				0
Fair value transfers, Level 1 to Level 2 liabilities			0				0
Fair value transfers, Level 2 to Level 1 liabilities			0				0
Restricted cash	$ 634,416	$ 634,416	$ 3,534,174
Per share exercise price \| $ / shares	$ 5.03	$ 5.03				$ 0.01
ASU 2016-02 [Member] \| Scenario, Forecast [Member]
Significant Accounting Policies [Line Items]
Operating lease, right-of-use asset				$ 2,000,000
Revenue from Rights Concentration Risk [Member] \| Research Grants and Contracts [Member]
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk		100.00%	100.00%
Revenue from Rights Concentration Risk [Member] \| Accounts Receivable [Member]
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk		100.00%	100.00%
Money Market Funds [Member]
Significant Accounting Policies [Line Items]
Restricted cash	$ 634,416	$ 634,416
IPR&D [Member]
Significant Accounting Policies [Line Items]
Number of assets \| Asset	3	3
Intangible assets, amount	$ 13,418,967	$ 13,418,967	$ 38,245,871				$ 14,477,019
Carrying value of assets	22,389,000	22,389,000
Impairment of intangible assets	21,389,000	24,450,011
IPR&D [Member] \| Oncosyn Cancer Immunotherapy [Member]
Significant Accounting Policies [Line Items]
Intangible assets, amount	$ 3,061,011	$ 3,061,011
IPR&D [Member] \| HepTcell and SparVax-L [Member]
Significant Accounting Policies [Line Items]
Number of assets \| Asset	2	2
IPR&D [Member] \| SparVax-L [Member]
Significant Accounting Policies [Line Items]
Fair value of intangible assets	$ 1,000,000	$ 1,000,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Intangible assets amortization period		6 years
Minimum [Member] \| Second Registered Direct Offering [Member]
Significant Accounting Policies [Line Items]
Per share exercise price \| $ / shares					$ 4.1798
Maximum [Member]
Significant Accounting Policies [Line Items]
Intangible assets amortization period		20 years
Maximum [Member] \| Second Registered Direct Offering [Member]
Significant Accounting Policies [Line Items]
Per share exercise price \| $ / shares					$ 6.00
Maximum [Member] \| IPR&D [Member] \| HepTcell [Member]
Significant Accounting Policies [Line Items]
Percent of fair value of reporting unit excess of carrying value	10.00%	10.00%