Summary of Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)
Significant Accounting Policies [Line Items]
Number of operating segments \| segment	1
Impairments	$ 579,497
Fair value transfers into Level 3	0	$ 0
Fair value transfers out of Level 3	0	0
Restricted cash	34,174	34,174
Income tax receivables	3,600,000	5,400,000
United Kingdom and Australia
Significant Accounting Policies [Line Items]
R&D credits	$ 1,800,000	$ 2,300,000
Revenue from Rights Concentration Risk [Member] \| Research Grants and Contracts [Member] \| U.S. government [Member]
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk	97.00%	97.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| U.S. government [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	$ 0
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

The amount of research and development incentive credits.

No definition available.

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Significant accounting policies.

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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 financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of level 3 of the fair value hierarchy.

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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 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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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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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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