Business Acquisition - Summary of Fair Value of Purchase Price Consideration (Parenthetical) (Detail) - Anelixis [Member]	Sep. 14, 2020 $ / shares shares
Business Acquisition [Line Items]
Expected stock price volatility, minimum	82.00%
Expected stock price volatility, maximum	83.00%
Risk-free interest rate, minimum	0.27%
Risk-free interest rate, maximum	0.45%
Minimum [Member]
Business Acquisition [Line Items]
Expected life of option (in years)	5 years
Maximum [Member]
Business Acquisition [Line Items]
Expected life of option (in years)	5 years 10 months 24 days
Common Stock [Member]
Business Acquisition [Line Items]
Business acquisition, shares issued \| shares	175,488
Business acquisition, closing price per share \| $ / shares	$ 6.80

Number of shares of equity interests issued or issuable to acquire entity.

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-Publisher FASB
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-SubTopic 30
-Section 50
-Paragraph 1
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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