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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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Amount recognized for uncertainty in income taxes classified as current.

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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 revenue and income classified as other.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) Segment	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of operating segment \| Segment			1
Uncertain tax positions	$ 0		$ 0		$ 0
Comprehensive income recognized		$ 15,000,000		$ 15,000,000	$ 15,000,000.0
Revenue, Product and Service [Extensible Enumeration]	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember
General and Administrative Expense [Member]
Summary Of Significant Accounting Policies [Line Items]
Loss on disposition of furniture and equipment	$ 93,285	$ 0	$ 93,285	$ 0
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Furniture and equipment estimated useful lives			3 years
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Furniture and equipment estimated useful lives			7 years
US Government Insured Loan Program [Member] \| Medical Technology Enterprise Consortium [Member]
Summary Of Significant Accounting Policies [Line Items]
Clinical trial discontinued as other income	$ 400,000	$ 0	$ 1,500,000	$ 0