Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
Dec. 31, 2020 USD ($) Segment	Dec. 31, 2019 USD ($)
Significant Accounting Policies [Line Items]
Number of operating segments \| Segment	1
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	$ 34,174	$ 34,174
Revenue from Rights Concentration Risk [Member] \| Research Grants and Contracts [Member]
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk	97.00%	95.00%
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	$ 34,174	$ 34,174
IPR&D [Member]
Significant Accounting Policies [Line Items]
Impairments	$ 0	$ 1,000,000
Minimum [Member]
Significant Accounting Policies [Line Items]
Intangible assets amortization period	6 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Intangible assets amortization period	20 years

Significant accounting policies.

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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.

+ References

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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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- Definition

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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- 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 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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